ptrace_stop() does preempt_enable_no_resched() to avoid the preemption,
but after that cgroup_enter_frozen() does spin_lock/unlock and this adds
another preemption point.
Reported-and-tested-by: Bruce Ashfield <bruce.ashfield@gmail.com>
Fixes: 76f969e8948d ("cgroup: cgroup v2 freezer")
Cc: stable@vger.kernel.org # v5.2+
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Roman Gushchin <guro@fb.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Change-Id: Ic53e0f2d6624b0bb90817b0c57060fb7db971348
(cherry picked from commit 937c6b27c73e02cd4114f95f5c37ba2c29fadba1)
Bug: 154548692
Signed-off-by: Marco Ballesio <balejs@google.com>
Alex Xu reported a regression in strace, caused by the introduction of
the cgroup v2 freezer. The regression can be reproduced by stracing
the following simple program:
#include <unistd.h>
int main() {
write(1, "a", 1);
return 0;
}
An attempt to run strace ./a.out leads to the infinite loop:
[ pre-main omitted ]
write(1, "a", 1) = ? ERESTARTSYS (To be restarted if SA_RESTART is set)
write(1, "a", 1) = ? ERESTARTSYS (To be restarted if SA_RESTART is set)
write(1, "a", 1) = ? ERESTARTSYS (To be restarted if SA_RESTART is set)
write(1, "a", 1) = ? ERESTARTSYS (To be restarted if SA_RESTART is set)
write(1, "a", 1) = ? ERESTARTSYS (To be restarted if SA_RESTART is set)
write(1, "a", 1) = ? ERESTARTSYS (To be restarted if SA_RESTART is set)
[ repeats forever ]
The problem occurs because the traced task leaves ptrace_stop()
(and the signal handling loop) with the frozen bit set. So let's
call cgroup_leave_frozen(true) unconditionally after sleeping
in ptrace_stop().
With this patch applied, strace works as expected:
[ pre-main omitted ]
write(1, "a", 1) = 1
exit_group(0) = ?
+++ exited with 0 +++
Reported-by: Alex Xu <alex_y_xu@yahoo.ca>
Fixes: 76f969e8948d ("cgroup: cgroup v2 freezer")
Signed-off-by: Roman Gushchin <guro@fb.com>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Tejun Heo <tj@kernel.org>
Change-Id: If644b15ead36ce13f0c2c3dd57eebe3658e3edf7
(cherry picked from commit 05b289263772b0698589abc47771264a685cd365)
Bug: 154548692
Signed-off-by: Marco Ballesio <balejs@google.com>
Cgroup v1 implements the freezer controller, which provides an ability
to stop the workload in a cgroup and temporarily free up some
resources (cpu, io, network bandwidth and, potentially, memory)
for some other tasks. Cgroup v2 lacks this functionality.
This patch implements freezer for cgroup v2.
Cgroup v2 freezer tries to put tasks into a state similar to jobctl
stop. This means that tasks can be killed, ptraced (using
PTRACE_SEIZE*), and interrupted. It is possible to attach to
a frozen task, get some information (e.g. read registers) and detach.
It's also possible to migrate a frozen tasks to another cgroup.
This differs cgroup v2 freezer from cgroup v1 freezer, which mostly
tried to imitate the system-wide freezer. However uninterruptible
sleep is fine when all tasks are going to be frozen (hibernation case),
it's not the acceptable state for some subset of the system.
Cgroup v2 freezer is not supporting freezing kthreads.
If a non-root cgroup contains kthread, the cgroup still can be frozen,
but the kthread will remain running, the cgroup will be shown
as non-frozen, and the notification will not be delivered.
* PTRACE_ATTACH is not working because non-fatal signal delivery
is blocked in frozen state.
There are some interface differences between cgroup v1 and cgroup v2
freezer too, which are required to conform the cgroup v2 interface
design principles:
1) There is no separate controller, which has to be turned on:
the functionality is always available and is represented by
cgroup.freeze and cgroup.events cgroup control files.
2) The desired state is defined by the cgroup.freeze control file.
Any hierarchical configuration is allowed.
3) The interface is asynchronous. The actual state is available
using cgroup.events control file ("frozen" field). There are no
dedicated transitional states.
4) It's allowed to make any changes with the cgroup hierarchy
(create new cgroups, remove old cgroups, move tasks between cgroups)
no matter if some cgroups are frozen.
Signed-off-by: Roman Gushchin <guro@fb.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
No-objection-from-me-by: Oleg Nesterov <oleg@redhat.com>
Cc: kernel-team@fb.com
Change-Id: I3404119678cbcd7410aa56e9334055cee79d02fa
(cherry picked from commit 76f969e8948d82e78e1bc4beb6b9465908e74873)
cgroup-defs.h: use the struct cgroup_freezer_state and the
freezer field from definitions in I6221a975c04f06249a4f8d693852776ae08a8d8e
sched.h: use the frozen field defined in
I6221a975c04f06249a4f8d693852776ae08a8d8e
Bug: 154548692
Signed-off-by: Marco Ballesio <balejs@google.com>
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Merge 4.19.116 into android-4.19
Changes in 4.19.116
ARM: dts: sun8i-a83t-tbs-a711: HM5065 doesn't like such a high voltage
bus: sunxi-rsb: Return correct data when mixing 16-bit and 8-bit reads
net: vxge: fix wrong __VA_ARGS__ usage
hinic: fix a bug of waitting for IO stopped
hinic: fix wrong para of wait_for_completion_timeout
cxgb4/ptp: pass the sign of offset delta in FW CMD
qlcnic: Fix bad kzalloc null test
i2c: st: fix missing struct parameter description
cpufreq: imx6q: Fixes unwanted cpu overclocking on i.MX6ULL
media: venus: hfi_parser: Ignore HEVC encoding for V1
firmware: arm_sdei: fix double-lock on hibernate with shared events
null_blk: Fix the null_add_dev() error path
null_blk: Handle null_add_dev() failures properly
null_blk: fix spurious IO errors after failed past-wp access
xhci: bail out early if driver can't accress host in resume
x86: Don't let pgprot_modify() change the page encryption bit
block: keep bdi->io_pages in sync with max_sectors_kb for stacked devices
irqchip/versatile-fpga: Handle chained IRQs properly
sched: Avoid scale real weight down to zero
selftests/x86/ptrace_syscall_32: Fix no-vDSO segfault
PCI/switchtec: Fix init_completion race condition with poll_wait()
media: i2c: video-i2c: fix build errors due to 'imply hwmon'
libata: Remove extra scsi_host_put() in ata_scsi_add_hosts()
pstore/platform: fix potential mem leak if pstore_init_fs failed
gfs2: Don't demote a glock until its revokes are written
x86/boot: Use unsigned comparison for addresses
efi/x86: Ignore the memory attributes table on i386
genirq/irqdomain: Check pointer in irq_domain_alloc_irqs_hierarchy()
block: Fix use-after-free issue accessing struct io_cq
media: i2c: ov5695: Fix power on and off sequences
usb: dwc3: core: add support for disabling SS instances in park mode
irqchip/gic-v4: Provide irq_retrigger to avoid circular locking dependency
md: check arrays is suspended in mddev_detach before call quiesce operations
firmware: fix a double abort case with fw_load_sysfs_fallback
locking/lockdep: Avoid recursion in lockdep_count_{for,back}ward_deps()
block, bfq: fix use-after-free in bfq_idle_slice_timer_body
btrfs: qgroup: ensure qgroup_rescan_running is only set when the worker is at least queued
btrfs: remove a BUG_ON() from merge_reloc_roots()
btrfs: track reloc roots based on their commit root bytenr
IB/mlx5: Replace tunnel mpls capability bits for tunnel_offloads
uapi: rename ext2_swab() to swab() and share globally in swab.h
slub: improve bit diffusion for freelist ptr obfuscation
ASoC: fix regwmask
ASoC: dapm: connect virtual mux with default value
ASoC: dpcm: allow start or stop during pause for backend
ASoC: topology: use name_prefix for new kcontrol
usb: gadget: f_fs: Fix use after free issue as part of queue failure
usb: gadget: composite: Inform controller driver of self-powered
ALSA: usb-audio: Add mixer workaround for TRX40 and co
ALSA: hda: Add driver blacklist
ALSA: hda: Fix potential access overflow in beep helper
ALSA: ice1724: Fix invalid access for enumerated ctl items
ALSA: pcm: oss: Fix regression by buffer overflow fix
ALSA: doc: Document PC Beep Hidden Register on Realtek ALC256
ALSA: hda/realtek - Set principled PC Beep configuration for ALC256
ALSA: hda/realtek - Remove now-unnecessary XPS 13 headphone noise fixups
ALSA: hda/realtek - Add quirk for MSI GL63
media: ti-vpe: cal: fix disable_irqs to only the intended target
acpi/x86: ignore unspecified bit positions in the ACPI global lock field
thermal: devfreq_cooling: inline all stubs for CONFIG_DEVFREQ_THERMAL=n
nvme-fc: Revert "add module to ops template to allow module references"
nvme: Treat discovery subsystems as unique subsystems
PCI: pciehp: Fix indefinite wait on sysfs requests
PCI/ASPM: Clear the correct bits when enabling L1 substates
PCI: Add boot interrupt quirk mechanism for Xeon chipsets
PCI: endpoint: Fix for concurrent memory allocation in OB address region
tpm: Don't make log failures fatal
tpm: tpm1_bios_measurements_next should increase position index
tpm: tpm2_bios_measurements_next should increase position index
KEYS: reaching the keys quotas correctly
irqchip/versatile-fpga: Apply clear-mask earlier
pstore: pstore_ftrace_seq_next should increase position index
MIPS/tlbex: Fix LDDIR usage in setup_pw() for Loongson-3
MIPS: OCTEON: irq: Fix potential NULL pointer dereference
ath9k: Handle txpower changes even when TPC is disabled
signal: Extend exec_id to 64bits
x86/entry/32: Add missing ASM_CLAC to general_protection entry
KVM: nVMX: Properly handle userspace interrupt window request
KVM: s390: vsie: Fix region 1 ASCE sanity shadow address checks
KVM: s390: vsie: Fix delivery of addressing exceptions
KVM: x86: Allocate new rmap and large page tracking when moving memslot
KVM: VMX: Always VMCLEAR in-use VMCSes during crash with kexec support
KVM: x86: Gracefully handle __vmalloc() failure during VM allocation
KVM: VMX: fix crash cleanup when KVM wasn't used
CIFS: Fix bug which the return value by asynchronous read is error
mtd: spinand: Stop using spinand->oobbuf for buffering bad block markers
mtd: spinand: Do not erase the block before writing a bad block marker
Btrfs: fix crash during unmount due to race with delayed inode workers
btrfs: set update the uuid generation as soon as possible
btrfs: drop block from cache on error in relocation
btrfs: fix missing file extent item for hole after ranged fsync
btrfs: fix missing semaphore unlock in btrfs_sync_file
crypto: mxs-dcp - fix scatterlist linearization for hash
erofs: correct the remaining shrink objects
powerpc/pseries: Drop pointless static qualifier in vpa_debugfs_init()
x86/speculation: Remove redundant arch_smt_update() invocation
tools: gpio: Fix out-of-tree build regression
mm: Use fixed constant in page_frag_alloc instead of size + 1
net: qualcomm: rmnet: Allow configuration updates to existing devices
arm64: dts: allwinner: h6: Fix PMU compatible
dm writecache: add cond_resched to avoid CPU hangs
dm verity fec: fix memory leak in verity_fec_dtr
scsi: zfcp: fix missing erp_lock in port recovery trigger for point-to-point
arm64: armv8_deprecated: Fix undef_hook mask for thumb setend
selftests: vm: drop dependencies on page flags from mlock2 tests
rtc: omap: Use define directive for PIN_CONFIG_ACTIVE_HIGH
drm/etnaviv: rework perfmon query infrastructure
powerpc/pseries: Avoid NULL pointer dereference when drmem is unavailable
NFS: Fix a page leak in nfs_destroy_unlinked_subrequests()
ext4: fix a data race at inode->i_blocks
fs/filesystems.c: downgrade user-reachable WARN_ONCE() to pr_warn_once()
ocfs2: no need try to truncate file beyond i_size
perf tools: Support Python 3.8+ in Makefile
s390/diag: fix display of diagnose call statistics
Input: i8042 - add Acer Aspire 5738z to nomux list
clk: ingenic/jz4770: Exit with error if CGU init failed
kmod: make request_module() return an error when autoloading is disabled
cpufreq: powernv: Fix use-after-free
hfsplus: fix crash and filesystem corruption when deleting files
libata: Return correct status in sata_pmp_eh_recover_pm() when ATA_DFLAG_DETACH is set
ipmi: fix hung processes in __get_guid()
xen/blkfront: fix memory allocation flags in blkfront_setup_indirect()
powerpc/powernv/idle: Restore AMR/UAMOR/AMOR after idle
powerpc/64/tm: Don't let userspace set regs->trap via sigreturn
powerpc/hash64/devmap: Use H_PAGE_THP_HUGE when setting up huge devmap PTE entries
powerpc/xive: Use XIVE_BAD_IRQ instead of zero to catch non configured IPIs
powerpc/kprobes: Ignore traps that happened in real mode
scsi: mpt3sas: Fix kernel panic observed on soft HBA unplug
powerpc: Add attributes for setjmp/longjmp
powerpc: Make setjmp/longjmp signature standard
btrfs: use nofs allocations for running delayed items
dm zoned: remove duplicate nr_rnd_zones increase in dmz_init_zone()
crypto: caam - update xts sector size for large input length
crypto: ccree - improve error handling
crypto: ccree - zero out internal struct before use
crypto: ccree - don't mangle the request assoclen
crypto: ccree - dec auth tag size from cryptlen map
crypto: ccree - only try to map auth tag if needed
Revert "drm/dp_mst: Remove VCPI while disabling topology mgr"
drm/dp_mst: Fix clearing payload state on topology disable
drm: Remove PageReserved manipulation from drm_pci_alloc
ftrace/kprobe: Show the maxactive number on kprobe_events
powerpc/fsl_booke: Avoid creating duplicate tlb1 entry
misc: echo: Remove unnecessary parentheses and simplify check for zero
etnaviv: perfmon: fix total and idle HI cyleces readout
mfd: dln2: Fix sanity checking for endpoints
efi/x86: Fix the deletion of variables in mixed mode
Linux 4.19.116
Change-Id: If09fbb53fcb11ea01eaaa7fee7ed21ed6234f352
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
commit d1e7fd6462ca9fc76650fbe6ca800e35b24267da upstream.
Replace the 32bit exec_id with a 64bit exec_id to make it impossible
to wrap the exec_id counter. With care an attacker can cause exec_id
wrap and send arbitrary signals to a newly exec'd parent. This
bypasses the signal sending checks if the parent changes their
credentials during exec.
The severity of this problem can been seen that in my limited testing
of a 32bit exec_id it can take as little as 19s to exec 65536 times.
Which means that it can take as little as 14 days to wrap a 32bit
exec_id. Adam Zabrocki has succeeded wrapping the self_exe_id in 7
days. Even my slower timing is in the uptime of a typical server.
Which means self_exec_id is simply a speed bump today, and if exec
gets noticably faster self_exec_id won't even be a speed bump.
Extending self_exec_id to 64bits introduces a problem on 32bit
architectures where reading self_exec_id is no longer atomic and can
take two read instructions. Which means that is is possible to hit
a window where the read value of exec_id does not match the written
value. So with very lucky timing after this change this still
remains expoiltable.
I have updated the update of exec_id on exec to use WRITE_ONCE
and the read of exec_id in do_notify_parent to use READ_ONCE
to make it clear that there is no locking between these two
locations.
Link: https://lore.kernel.org/kernel-hardening/20200324215049.GA3710@pi3.com.pl
Fixes: 2.3.23pre2
Cc: stable@vger.kernel.org
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge 4.19.112 into android-4.19
Changes in 4.19.112
perf/amd/uncore: Replace manual sampling check with CAP_NO_INTERRUPT flag
mmc: sdhci-omap: Add platform specific reset callback
mmc: sdhci-omap: Workaround errata regarding SDR104/HS200 tuning failures (i929)
mmc: host: Fix Kconfig warnings on keystone_defconfig
ACPI: watchdog: Allow disabling WDAT at boot
HID: apple: Add support for recent firmware on Magic Keyboards
HID: i2c-hid: add Trekstor Surfbook E11B to descriptor override
cfg80211: check reg_rule for NULL in handle_channel_custom()
scsi: libfc: free response frame from GPN_ID
net: usb: qmi_wwan: restore mtu min/max values after raw_ip switch
net: ks8851-ml: Fix IRQ handling and locking
mac80211: rx: avoid RCU list traversal under mutex
signal: avoid double atomic counter increments for user accounting
slip: not call free_netdev before rtnl_unlock in slip_open
hinic: fix a irq affinity bug
hinic: fix a bug of setting hw_ioctxt
net: rmnet: fix NULL pointer dereference in rmnet_newlink()
net: rmnet: fix NULL pointer dereference in rmnet_changelink()
net: rmnet: fix suspicious RCU usage
net: rmnet: remove rcu_read_lock in rmnet_force_unassociate_device()
net: rmnet: do not allow to change mux id if mux id is duplicated
net: rmnet: use upper/lower device infrastructure
net: rmnet: fix bridge mode bugs
net: rmnet: fix packet forwarding in rmnet bridge mode
sfc: fix timestamp reconstruction at 16-bit rollover points
jbd2: fix data races at struct journal_head
wimax: i2400: fix memory leak
wimax: i2400: Fix memory leak in i2400m_op_rfkill_sw_toggle
mmc: sdhci-omap: Don't finish_mrq() on a command error during tuning
mmc: sdhci-omap: Fix Tuning procedure for temperatures < -20C
driver core: Remove the link if there is no driver with AUTO flag
driver core: Fix adding device links to probing suppliers
driver core: Make driver core own stateful device links
driver core: Add device link flag DL_FLAG_AUTOPROBE_CONSUMER
driver core: Remove device link creation limitation
driver core: Fix creation of device links with PM-runtime flags
net: qrtr: fix len of skb_put_padto in qrtr_node_enqueue
ARM: 8957/1: VDSO: Match ARMv8 timer in cntvct_functional()
ARM: 8958/1: rename missed uaccess .fixup section
mm: slub: add missing TID bump in kmem_cache_alloc_bulk()
HID: google: add moonball USB id
efi: Fix debugobjects warning on 'efi_rts_work'
ipv4: ensure rcu_read_lock() in cipso_v4_error()
Linux 4.19.112
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
Change-Id: I68bb3ea9d74f698994a1b958d112827a0873a0f7
[ Upstream commit fda31c50292a5062332fa0343c084bd9f46604d9 ]
When queueing a signal, we increment both the users count of pending
signals (for RLIMIT_SIGPENDING tracking) and we increment the refcount
of the user struct itself (because we keep a reference to the user in
the signal structure in order to correctly account for it when freeing).
That turns out to be fairly expensive, because both of them are atomic
updates, and particularly under extreme signal handling pressure on big
machines, you can get a lot of cache contention on the user struct.
That can then cause horrid cacheline ping-pong when you do these
multiple accesses.
So change the reference counting to only pin the user for the _first_
pending signal, and to unpin it when the last pending signal is
dequeued. That means that when a user sees a lot of concurrent signal
queuing - which is the only situation when this matters - the only
atomic access needed is generally the 'sigpending' count update.
This was noticed because of a particularly odd timing artifact on a
dual-socket 96C/192T Cascade Lake platform: when you get into bad
contention, on that machine for some reason seems to be much worse when
the contention happens in the upper 32-byte half of the cacheline.
As a result, the kernel test robot will-it-scale 'signal1' benchmark had
an odd performance regression simply due to random alignment of the
'struct user_struct' (and pointed to a completely unrelated and
apparently nonsensical commit for the regression).
Avoiding the double increments (and decrements on the dequeueing side,
of course) makes for much less contention and hugely improved
performance on that will-it-scale microbenchmark.
Quoting Feng Tang:
"It makes a big difference, that the performance score is tripled! bump
from original 17000 to 54000. Also the gap between 5.0-rc6 and
5.0-rc6+Jiri's patch is reduced to around 2%"
[ The "2% gap" is the odd cacheline placement difference on that
platform: under the extreme contention case, the effect of which half
of the cacheline was hot was 5%, so with the reduced contention the
odd timing artifact is reduced too ]
It does help in the non-contended case too, but is not nearly as
noticeable.
Reported-and-tested-by: Feng Tang <feng.tang@intel.com>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Huang, Ying <ying.huang@intel.com>
Cc: Philip Li <philip.li@intel.com>
Cc: Andi Kleen <andi.kleen@intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
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Merge 4.19.99 into android-4.19
Changes in 4.19.99
Revert "efi: Fix debugobjects warning on 'efi_rts_work'"
xfs: Sanity check flags of Q_XQUOTARM call
i2c: stm32f7: rework slave_id allocation
i2c: i2c-stm32f7: fix 10-bits check in slave free id search loop
mfd: intel-lpss: Add default I2C device properties for Gemini Lake
SUNRPC: Fix svcauth_gss_proxy_init()
powerpc/pseries: Enable support for ibm,drc-info property
powerpc/archrandom: fix arch_get_random_seed_int()
tipc: update mon's self addr when node addr generated
tipc: fix wrong timeout input for tipc_wait_for_cond()
mt7601u: fix bbp version check in mt7601u_wait_bbp_ready
crypto: sun4i-ss - fix big endian issues
perf map: No need to adjust the long name of modules
soc: aspeed: Fix snoop_file_poll()'s return type
watchdog: sprd: Fix the incorrect pointer getting from driver data
ipmi: Fix memory leak in __ipmi_bmc_register
drm/sti: do not remove the drm_bridge that was never added
ARM: dts: at91: nattis: set the PRLUD and HIPOW signals low
ARM: dts: at91: nattis: make the SD-card slot work
ixgbe: don't clear IPsec sa counters on HW clearing
drm/virtio: fix bounds check in virtio_gpu_cmd_get_capset()
iio: fix position relative kernel version
apparmor: Fix network performance issue in aa_label_sk_perm
ALSA: hda: fix unused variable warning
apparmor: don't try to replace stale label in ptrace access check
ARM: qcom_defconfig: Enable MAILBOX
firmware: coreboot: Let OF core populate platform device
PCI: iproc: Remove PAXC slot check to allow VF support
bridge: br_arp_nd_proxy: set icmp6_router if neigh has NTF_ROUTER
drm/hisilicon: hibmc: Don't overwrite fb helper surface depth
signal/ia64: Use the generic force_sigsegv in setup_frame
signal/ia64: Use the force_sig(SIGSEGV,...) in ia64_rt_sigreturn
ASoC: wm9712: fix unused variable warning
mailbox: mediatek: Add check for possible failure of kzalloc
IB/rxe: replace kvfree with vfree
IB/hfi1: Add mtu check for operational data VLs
genirq/debugfs: Reinstate full OF path for domain name
usb: dwc3: add EXTCON dependency for qcom
usb: gadget: fsl_udc_core: check allocation return value and cleanup on failure
cfg80211: regulatory: make initialization more robust
mei: replace POLL* with EPOLL* for write queues.
drm/msm: fix unsigned comparison with less than zero
of: Fix property name in of_node_get_device_type
ALSA: usb-audio: update quirk for B&W PX to remove microphone
iwlwifi: nvm: get num of hw addresses from firmware
staging: comedi: ni_mio_common: protect register write overflow
netfilter: nft_osf: usage from output path is not valid
pwm: lpss: Release runtime-pm reference from the driver's remove callback
powerpc/pseries/memory-hotplug: Fix return value type of find_aa_index
rtlwifi: rtl8821ae: replace _rtl8821ae_mrate_idx_to_arfr_id with generic version
RDMA/bnxt_re: Add missing spin lock initialization
netfilter: nf_flow_table: do not remove offload when other netns's interface is down
powerpc/kgdb: add kgdb_arch_set/remove_breakpoint()
tipc: eliminate message disordering during binding table update
net: socionext: Add dummy PHY register read in phy_write()
drm/sun4i: hdmi: Fix double flag assignation
net: hns3: add error handler for hns3_nic_init_vector_data()
mlxsw: reg: QEEC: Add minimum shaper fields
mlxsw: spectrum: Set minimum shaper on MC TCs
NTB: ntb_hw_idt: replace IS_ERR_OR_NULL with regular NULL checks
ASoC: wm97xx: fix uninitialized regmap pointer problem
ARM: dts: bcm283x: Correct mailbox register sizes
pcrypt: use format specifier in kobject_add
ASoC: sun8i-codec: add missing route for ADC
pinctrl: meson-gxl: remove invalid GPIOX tsin_a pins
bus: ti-sysc: Add mcasp optional clocks flag
exportfs: fix 'passing zero to ERR_PTR()' warning
drm: rcar-du: Fix the return value in case of error in 'rcar_du_crtc_set_crc_source()'
drm: rcar-du: Fix vblank initialization
net: always initialize pagedlen
drm/dp_mst: Skip validating ports during destruction, just ref
arm64: dts: meson-gx: Add hdmi_5v regulator as hdmi tx supply
arm64: dts: renesas: r8a7795-es1: Add missing power domains to IPMMU nodes
net: phy: Fix not to call phy_resume() if PHY is not attached
IB/hfi1: Correctly process FECN and BECN in packets
OPP: Fix missing debugfs supply directory for OPPs
IB/rxe: Fix incorrect cache cleanup in error flow
mailbox: ti-msgmgr: Off by one in ti_msgmgr_of_xlate()
staging: bcm2835-camera: Abort probe if there is no camera
staging: bcm2835-camera: fix module autoloading
switchtec: Remove immediate status check after submitting MRPC command
ipv6: add missing tx timestamping on IPPROTO_RAW
pinctrl: sh-pfc: r8a7740: Add missing REF125CK pin to gether_gmii group
pinctrl: sh-pfc: r8a7740: Add missing LCD0 marks to lcd0_data24_1 group
pinctrl: sh-pfc: r8a7791: Remove bogus ctrl marks from qspi_data4_b group
pinctrl: sh-pfc: r8a7791: Remove bogus marks from vin1_b_data18 group
pinctrl: sh-pfc: sh73a0: Add missing TO pin to tpu4_to3 group
pinctrl: sh-pfc: r8a7794: Remove bogus IPSR9 field
pinctrl: sh-pfc: r8a77970: Add missing MOD_SEL0 field
pinctrl: sh-pfc: r8a77980: Add missing MOD_SEL0 field
pinctrl: sh-pfc: sh7734: Add missing IPSR11 field
pinctrl: sh-pfc: r8a77995: Remove bogus SEL_PWM[0-3]_3 configurations
pinctrl: sh-pfc: sh7269: Add missing PCIOR0 field
pinctrl: sh-pfc: sh7734: Remove bogus IPSR10 value
net: hns3: fix error handling int the hns3_get_vector_ring_chain
vxlan: changelink: Fix handling of default remotes
Input: nomadik-ske-keypad - fix a loop timeout test
fork,memcg: fix crash in free_thread_stack on memcg charge fail
clk: highbank: fix refcount leak in hb_clk_init()
clk: qoriq: fix refcount leak in clockgen_init()
clk: ti: fix refcount leak in ti_dt_clocks_register()
clk: socfpga: fix refcount leak
clk: samsung: exynos4: fix refcount leak in exynos4_get_xom()
clk: imx6q: fix refcount leak in imx6q_clocks_init()
clk: imx6sx: fix refcount leak in imx6sx_clocks_init()
clk: imx7d: fix refcount leak in imx7d_clocks_init()
clk: vf610: fix refcount leak in vf610_clocks_init()
clk: armada-370: fix refcount leak in a370_clk_init()
clk: kirkwood: fix refcount leak in kirkwood_clk_init()
clk: armada-xp: fix refcount leak in axp_clk_init()
clk: mv98dx3236: fix refcount leak in mv98dx3236_clk_init()
clk: dove: fix refcount leak in dove_clk_init()
MIPS: BCM63XX: drop unused and broken DSP platform device
arm64: defconfig: Re-enable bcm2835-thermal driver
remoteproc: qcom: q6v5-mss: Add missing clocks for MSM8996
remoteproc: qcom: q6v5-mss: Add missing regulator for MSM8996
drm: Fix error handling in drm_legacy_addctx
ARM: dts: r8a7743: Remove generic compatible string from iic3
drm/etnaviv: fix some off by one bugs
drm/fb-helper: generic: Fix setup error path
fork, memcg: fix cached_stacks case
IB/usnic: Fix out of bounds index check in query pkey
RDMA/ocrdma: Fix out of bounds index check in query pkey
RDMA/qedr: Fix out of bounds index check in query pkey
drm/shmob: Fix return value check in shmob_drm_probe
arm64: dts: apq8016-sbc: Increase load on l11 for SDCARD
spi: cadence: Correct initialisation of runtime PM
RDMA/iw_cxgb4: Fix the unchecked ep dereference
net: phy: micrel: set soft_reset callback to genphy_soft_reset for KSZ9031
memory: tegra: Don't invoke Tegra30+ specific memory timing setup on Tegra20
drm/etnaviv: NULL vs IS_ERR() buf in etnaviv_core_dump()
media: s5p-jpeg: Correct step and max values for V4L2_CID_JPEG_RESTART_INTERVAL
kbuild: mark prepare0 as PHONY to fix external module build
crypto: brcm - Fix some set-but-not-used warning
crypto: tgr192 - fix unaligned memory access
ASoC: imx-sgtl5000: put of nodes if finding codec fails
IB/iser: Pass the correct number of entries for dma mapped SGL
net: hns3: fix wrong combined count returned by ethtool -l
media: tw9910: Unregister subdevice with v4l2-async
IB/mlx5: Don't override existing ip_protocol
rtc: cmos: ignore bogus century byte
spi/topcliff_pch: Fix potential NULL dereference on allocation error
net: hns3: fix bug of ethtool_ops.get_channels for VF
ARM: dts: sun8i-a23-a33: Move NAND controller device node to sort by address
clk: sunxi-ng: sun8i-a23: Enable PLL-MIPI LDOs when ungating it
iwlwifi: mvm: avoid possible access out of array.
net/mlx5: Take lock with IRQs disabled to avoid deadlock
ip_tunnel: Fix route fl4 init in ip_md_tunnel_xmit
arm64: dts: allwinner: h6: Move GIC device node fix base address ordering
iwlwifi: mvm: fix A-MPDU reference assignment
bus: ti-sysc: Fix timer handling with drop pm_runtime_irq_safe()
tty: ipwireless: Fix potential NULL pointer dereference
driver: uio: fix possible memory leak in __uio_register_device
driver: uio: fix possible use-after-free in __uio_register_device
crypto: crypto4xx - Fix wrong ppc4xx_trng_probe()/ppc4xx_trng_remove() arguments
driver core: Fix DL_FLAG_AUTOREMOVE_SUPPLIER device link flag handling
driver core: Avoid careless re-use of existing device links
driver core: Do not resume suppliers under device_links_write_lock()
driver core: Fix handling of runtime PM flags in device_link_add()
driver core: Do not call rpm_put_suppliers() in pm_runtime_drop_link()
ARM: dts: lpc32xx: add required clocks property to keypad device node
ARM: dts: lpc32xx: reparent keypad controller to SIC1
ARM: dts: lpc32xx: fix ARM PrimeCell LCD controller variant
ARM: dts: lpc32xx: fix ARM PrimeCell LCD controller clocks property
ARM: dts: lpc32xx: phy3250: fix SD card regulator voltage
drm/xen-front: Fix mmap attributes for display buffers
iwlwifi: mvm: fix RSS config command
staging: most: cdev: add missing check for cdev_add failure
clk: ingenic: jz4740: Fix gating of UDC clock
rtc: ds1672: fix unintended sign extension
thermal: mediatek: fix register index error
arm64: dts: msm8916: remove bogus argument to the cpu clock
ath10k: fix dma unmap direction for management frames
net: phy: fixed_phy: Fix fixed_phy not checking GPIO
rtc: ds1307: rx8130: Fix alarm handling
net/smc: original socket family in inet_sock_diag
rtc: 88pm860x: fix unintended sign extension
rtc: 88pm80x: fix unintended sign extension
rtc: pm8xxx: fix unintended sign extension
fbdev: chipsfb: remove set but not used variable 'size'
iw_cxgb4: use tos when importing the endpoint
iw_cxgb4: use tos when finding ipv6 routes
ipmi: kcs_bmc: handle devm_kasprintf() failure case
xsk: add missing smp_rmb() in xsk_mmap
drm/etnaviv: potential NULL dereference
ntb_hw_switchtec: debug print 64bit aligned crosslink BAR Numbers
ntb_hw_switchtec: NT req id mapping table register entry number should be 512
pinctrl: sh-pfc: emev2: Add missing pinmux functions
pinctrl: sh-pfc: r8a7791: Fix scifb2_data_c pin group
pinctrl: sh-pfc: r8a7792: Fix vin1_data18_b pin group
pinctrl: sh-pfc: sh73a0: Fix fsic_spdif pin groups
RDMA/mlx5: Fix memory leak in case we fail to add an IB device
driver core: Fix possible supplier PM-usage counter imbalance
PCI: endpoint: functions: Use memcpy_fromio()/memcpy_toio()
usb: phy: twl6030-usb: fix possible use-after-free on remove
block: don't use bio->bi_vcnt to figure out segment number
keys: Timestamp new keys
net: dsa: b53: Fix default VLAN ID
net: dsa: b53: Properly account for VLAN filtering
net: dsa: b53: Do not program CPU port's PVID
mt76: usb: fix possible memory leak in mt76u_buf_free
media: sh: migor: Include missing dma-mapping header
vfio_pci: Enable memory accesses before calling pci_map_rom
hwmon: (pmbus/tps53679) Fix driver info initialization in probe routine
mdio_bus: Fix PTR_ERR() usage after initialization to constant
KVM: PPC: Release all hardware TCE tables attached to a group
staging: r8822be: check kzalloc return or bail
dmaengine: mv_xor: Use correct device for DMA API
cdc-wdm: pass return value of recover_from_urb_loss
brcmfmac: create debugfs files for bus-specific layer
regulator: pv88060: Fix array out-of-bounds access
regulator: pv88080: Fix array out-of-bounds access
regulator: pv88090: Fix array out-of-bounds access
net: dsa: qca8k: Enable delay for RGMII_ID mode
net/mlx5: Delete unused FPGA QPN variable
drm/nouveau/bios/ramcfg: fix missing parentheses when calculating RON
drm/nouveau/pmu: don't print reply values if exec is false
drm/nouveau: fix missing break in switch statement
driver core: Fix PM-runtime for links added during consumer probe
ASoC: qcom: Fix of-node refcount unbalance in apq8016_sbc_parse_of()
net: dsa: fix unintended change of bridge interface STP state
fs/nfs: Fix nfs_parse_devname to not modify it's argument
staging: rtlwifi: Use proper enum for return in halmac_parse_psd_data_88xx
powerpc/64s: Fix logic when handling unknown CPU features
NFS: Fix a soft lockup in the delegation recovery code
perf: Copy parent's address filter offsets on clone
perf, pt, coresight: Fix address filters for vmas with non-zero offset
clocksource/drivers/sun5i: Fail gracefully when clock rate is unavailable
clocksource/drivers/exynos_mct: Fix error path in timer resources initialization
platform/x86: wmi: fix potential null pointer dereference
NFS/pnfs: Bulk destroy of layouts needs to be safe w.r.t. umount
mmc: sdhci-brcmstb: handle mmc_of_parse() errors during probe
iommu: Fix IOMMU debugfs fallout
ARM: 8847/1: pm: fix HYP/SVC mode mismatch when MCPM is used
ARM: 8848/1: virt: Align GIC version check with arm64 counterpart
ARM: 8849/1: NOMMU: Fix encodings for PMSAv8's PRBAR4/PRLAR4
regulator: wm831x-dcdc: Fix list of wm831x_dcdc_ilim from mA to uA
ath10k: Fix length of wmi tlv command for protected mgmt frames
netfilter: nft_set_hash: fix lookups with fixed size hash on big endian
netfilter: nft_set_hash: bogus element self comparison from deactivation path
net: sched: act_csum: Fix csum calc for tagged packets
hwrng: bcm2835 - fix probe as platform device
iommu/vt-d: Fix NULL pointer reference in intel_svm_bind_mm()
NFS: Add missing encode / decode sequence_maxsz to v4.2 operations
NFSv4/flexfiles: Fix invalid deref in FF_LAYOUT_DEVID_NODE()
net: aquantia: fixed instack structure overflow
powerpc/mm: Check secondary hash page table
media: dvb/earth-pt1: fix wrong initialization for demod blocks
rbd: clear ->xferred on error from rbd_obj_issue_copyup()
PCI: Fix "try" semantics of bus and slot reset
nios2: ksyms: Add missing symbol exports
x86/mm: Remove unused variable 'cpu'
scsi: megaraid_sas: reduce module load time
nfp: fix simple vNIC mailbox length
drivers/rapidio/rio_cm.c: fix potential oops in riocm_ch_listen()
xen, cpu_hotplug: Prevent an out of bounds access
net/mlx5: Fix multiple updates of steering rules in parallel
net/mlx5e: IPoIB, Fix RX checksum statistics update
net: sh_eth: fix a missing check of of_get_phy_mode
regulator: lp87565: Fix missing register for LP87565_BUCK_0
soc: amlogic: gx-socinfo: Add mask for each SoC packages
media: ivtv: update *pos correctly in ivtv_read_pos()
media: cx18: update *pos correctly in cx18_read_pos()
media: wl128x: Fix an error code in fm_download_firmware()
media: cx23885: check allocation return
regulator: tps65086: Fix tps65086_ldoa1_ranges for selector 0xB
crypto: ccree - reduce kernel stack usage with clang
jfs: fix bogus variable self-initialization
tipc: tipc clang warning
m68k: mac: Fix VIA timer counter accesses
ARM: dts: sun8i: a33: Reintroduce default pinctrl muxing
arm64: dts: allwinner: a64: Add missing PIO clocks
ARM: dts: sun9i: optimus: Fix fixed-regulators
net: phy: don't clear BMCR in genphy_soft_reset
ARM: OMAP2+: Fix potentially uninitialized return value for _setup_reset()
net: dsa: Avoid null pointer when failing to connect to PHY
soc: qcom: cmd-db: Fix an error code in cmd_db_dev_probe()
media: davinci-isif: avoid uninitialized variable use
media: tw5864: Fix possible NULL pointer dereference in tw5864_handle_frame
spi: tegra114: clear packed bit for unpacked mode
spi: tegra114: fix for unpacked mode transfers
spi: tegra114: terminate dma and reset on transfer timeout
spi: tegra114: flush fifos
spi: tegra114: configure dma burst size to fifo trig level
bus: ti-sysc: Fix sysc_unprepare() when no clocks have been allocated
soc/fsl/qe: Fix an error code in qe_pin_request()
spi: bcm2835aux: fix driver to not allow 65535 (=-1) cs-gpios
drm/fb-helper: generic: Call drm_client_add() after setup is done
arm64/vdso: don't leak kernel addresses
rtc: Fix timestamp value for RTC_TIMESTAMP_BEGIN_1900
rtc: mt6397: Don't call irq_dispose_mapping.
ehea: Fix a copy-paste err in ehea_init_port_res
bpf: Add missed newline in verifier verbose log
drm/vmwgfx: Remove set but not used variable 'restart'
scsi: qla2xxx: Unregister chrdev if module initialization fails
of: use correct function prototype for of_overlay_fdt_apply()
net/sched: cbs: fix port_rate miscalculation
clk: qcom: Skip halt checks on gcc_pcie_0_pipe_clk for 8998
ACPI: button: reinitialize button state upon resume
firmware: arm_scmi: fix of_node leak in scmi_mailbox_check
rxrpc: Fix detection of out of order acks
scsi: target/core: Fix a race condition in the LUN lookup code
brcmfmac: fix leak of mypkt on error return path
ARM: pxa: ssp: Fix "WARNING: invalid free of devm_ allocated data"
PCI: rockchip: Fix rockchip_pcie_ep_assert_intx() bitwise operations
net: hns3: fix for vport->bw_limit overflow problem
hwmon: (w83627hf) Use request_muxed_region for Super-IO accesses
perf/core: Fix the address filtering fix
staging: android: vsoc: fix copy_from_user overrun
PCI: dwc: Fix dw_pcie_ep_find_capability() to return correct capability offset
soc: amlogic: meson-gx-pwrc-vpu: Fix power on/off register bitmask
platform/x86: alienware-wmi: fix kfree on potentially uninitialized pointer
tipc: set sysctl_tipc_rmem and named_timeout right range
usb: typec: tcpm: Notify the tcpc to start connection-detection for SRPs
selftests/ipc: Fix msgque compiler warnings
net: hns3: fix loop condition of hns3_get_tx_timeo_queue_info()
powerpc: vdso: Make vdso32 installation conditional in vdso_install
ARM: dts: ls1021: Fix SGMII PCS link remaining down after PHY disconnect
media: ov2659: fix unbalanced mutex_lock/unlock
6lowpan: Off by one handling ->nexthdr
dmaengine: axi-dmac: Don't check the number of frames for alignment
ALSA: usb-audio: Handle the error from snd_usb_mixer_apply_create_quirk()
afs: Fix AFS file locking to allow fine grained locks
afs: Further fix file locking
NFS: Don't interrupt file writeout due to fatal errors
coresight: catu: fix clang build warning
s390/kexec_file: Fix potential segment overlap in ELF loader
irqchip/gic-v3-its: fix some definitions of inner cacheability attributes
scsi: qla2xxx: Fix a format specifier
scsi: qla2xxx: Fix error handling in qlt_alloc_qfull_cmd()
scsi: qla2xxx: Avoid that qlt_send_resp_ctio() corrupts memory
KVM: PPC: Book3S HV: Fix lockdep warning when entering the guest
netfilter: nft_flow_offload: add entry to flowtable after confirmation
PCI: iproc: Enable iProc config read for PAXBv2
ARM: dts: logicpd-som-lv: Fix MMC1 card detect
packet: in recvmsg msg_name return at least sizeof sockaddr_ll
ASoC: fix valid stream condition
usb: gadget: fsl: fix link error against usb-gadget module
dwc2: gadget: Fix completed transfer size calculation in DDMA
IB/mlx5: Add missing XRC options to QP optional params mask
RDMA/rxe: Consider skb reserve space based on netdev of GID
iommu/vt-d: Make kernel parameter igfx_off work with vIOMMU
net: ena: fix swapped parameters when calling ena_com_indirect_table_fill_entry
net: ena: fix: Free napi resources when ena_up() fails
net: ena: fix incorrect test of supported hash function
net: ena: fix ena_com_fill_hash_function() implementation
dmaengine: tegra210-adma: restore channel status
watchdog: rtd119x_wdt: Fix remove function
mmc: core: fix possible use after free of host
lightnvm: pblk: fix lock order in pblk_rb_tear_down_check
ath10k: Fix encoding for protected management frames
afs: Fix the afs.cell and afs.volume xattr handlers
vfio/mdev: Avoid release parent reference during error path
vfio/mdev: Follow correct remove sequence
vfio/mdev: Fix aborting mdev child device removal if one fails
l2tp: Fix possible NULL pointer dereference
ALSA: aica: Fix a long-time build breakage
media: omap_vout: potential buffer overflow in vidioc_dqbuf()
media: davinci/vpbe: array underflow in vpbe_enum_outputs()
platform/x86: alienware-wmi: printing the wrong error code
crypto: caam - fix caam_dump_sg that iterates through scatterlist
netfilter: ebtables: CONFIG_COMPAT: reject trailing data after last rule
pwm: meson: Consider 128 a valid pre-divider
pwm: meson: Don't disable PWM when setting duty repeatedly
ARM: riscpc: fix lack of keyboard interrupts after irq conversion
nfp: bpf: fix static check error through tightening shift amount adjustment
kdb: do a sanity check on the cpu in kdb_per_cpu()
netfilter: nf_tables: correct NFT_LOGLEVEL_MAX value
backlight: lm3630a: Return 0 on success in update_status functions
thermal: rcar_gen3_thermal: fix interrupt type
thermal: cpu_cooling: Actually trace CPU load in thermal_power_cpu_get_power
EDAC/mc: Fix edac_mc_find() in case no device is found
afs: Fix key leak in afs_release() and afs_evict_inode()
afs: Don't invalidate callback if AFS_VNODE_DIR_VALID not set
afs: Fix lock-wait/callback-break double locking
afs: Fix double inc of vnode->cb_break
ARM: dts: sun8i-h3: Fix wifi in Beelink X2 DT
clk: meson: gxbb: no spread spectrum on mpll0
clk: meson: axg: spread spectrum is on mpll2
dmaengine: tegra210-adma: Fix crash during probe
arm64: dts: meson: libretech-cc: set eMMC as removable
RDMA/qedr: Fix incorrect device rate.
spi: spi-fsl-spi: call spi_finalize_current_message() at the end
crypto: ccp - fix AES CFB error exposed by new test vectors
crypto: ccp - Fix 3DES complaint from ccp-crypto module
serial: stm32: fix word length configuration
serial: stm32: fix rx error handling
serial: stm32: fix rx data length when parity enabled
serial: stm32: fix transmit_chars when tx is stopped
serial: stm32: Add support of TC bit status check
serial: stm32: fix wakeup source initialization
misc: sgi-xp: Properly initialize buf in xpc_get_rsvd_page_pa
iommu: Add missing new line for dma type
iommu: Use right function to get group for device
signal/bpfilter: Fix bpfilter_kernl to use send_sig not force_sig
signal/cifs: Fix cifs_put_tcp_session to call send_sig instead of force_sig
inet: frags: call inet_frags_fini() after unregister_pernet_subsys()
net: hns3: fix a memory leak issue for hclge_map_unmap_ring_to_vf_vector
crypto: talitos - fix AEAD processing.
netvsc: unshare skb in VF rx handler
net: core: support XDP generic on stacked devices.
RDMA/uverbs: check for allocation failure in uapi_add_elm()
net: don't clear sock->sk early to avoid trouble in strparser
phy: qcom-qusb2: fix missing assignment of ret when calling clk_prepare_enable
cpufreq: brcmstb-avs-cpufreq: Fix initial command check
cpufreq: brcmstb-avs-cpufreq: Fix types for voltage/frequency
clk: sunxi-ng: sun50i-h6-r: Fix incorrect W1 clock gate register
media: vivid: fix incorrect assignment operation when setting video mode
crypto: inside-secure - fix zeroing of the request in ahash_exit_inv
crypto: inside-secure - fix queued len computation
arm64: dts: renesas: ebisu: Remove renesas, no-ether-link property
mpls: fix warning with multi-label encap
serial: stm32: fix a recursive locking in stm32_config_rs485
arm64: dts: meson-gxm-khadas-vim2: fix gpio-keys-polled node
arm64: dts: meson-gxm-khadas-vim2: fix Bluetooth support
iommu/vt-d: Duplicate iommu_resv_region objects per device list
phy: usb: phy-brcm-usb: Remove sysfs attributes upon driver removal
firmware: arm_scmi: fix bitfield definitions for SENSOR_DESC attributes
firmware: arm_scmi: update rate_discrete in clock_describe_rates_get
ntb_hw_switchtec: potential shift wrapping bug in switchtec_ntb_init_sndev()
ASoC: meson: axg-tdmin: right_j is not supported
ASoC: meson: axg-tdmout: right_j is not supported
qed: iWARP - Use READ_ONCE and smp_store_release to access ep->state
qed: iWARP - fix uninitialized callback
powerpc/cacheinfo: add cacheinfo_teardown, cacheinfo_rebuild
powerpc/pseries/mobility: rebuild cacheinfo hierarchy post-migration
bpf: fix the check that forwarding is enabled in bpf_ipv6_fib_lookup
IB/hfi1: Handle port down properly in pio
drm/msm/mdp5: Fix mdp5_cfg_init error return
net: netem: fix backlog accounting for corrupted GSO frames
net/udp_gso: Allow TX timestamp with UDP GSO
net/af_iucv: build proper skbs for HiperTransport
net/af_iucv: always register net_device notifier
ASoC: ti: davinci-mcasp: Fix slot mask settings when using multiple AXRs
rtc: pcf8563: Fix interrupt trigger method
rtc: pcf8563: Clear event flags and disable interrupts before requesting irq
ARM: dts: iwg20d-q7-common: Fix SDHI1 VccQ regularor
net/sched: cbs: Fix error path of cbs_module_init
arm64: dts: allwinner: h6: Pine H64: Add interrupt line for RTC
drm/msm/a3xx: remove TPL1 regs from snapshot
ip6_fib: Don't discard nodes with valid routing information in fib6_locate_1()
perf/ioctl: Add check for the sample_period value
dmaengine: hsu: Revert "set HSU_CH_MTSR to memory width"
clk: qcom: Fix -Wunused-const-variable
nvmem: imx-ocotp: Ensure WAIT bits are preserved when setting timing
nvmem: imx-ocotp: Change TIMING calculation to u-boot algorithm
tools: bpftool: use correct argument in cgroup errors
backlight: pwm_bl: Fix heuristic to determine number of brightness levels
fork,memcg: alloc_thread_stack_node needs to set tsk->stack
bnxt_en: Fix ethtool selftest crash under error conditions.
bnxt_en: Suppress error messages when querying DSCP DCB capabilities.
iommu/amd: Make iommu_disable safer
mfd: intel-lpss: Release IDA resources
rxrpc: Fix uninitialized error code in rxrpc_send_data_packet()
xprtrdma: Fix use-after-free in rpcrdma_post_recvs
um: Fix IRQ controller regression on console read
PM: ACPI/PCI: Resume all devices during hibernation
ACPI: PM: Simplify and fix PM domain hibernation callbacks
ACPI: PM: Introduce "poweroff" callbacks for ACPI PM domain and LPSS
fsi/core: Fix error paths on CFAM init
devres: allow const resource arguments
fsi: sbefifo: Don't fail operations when in SBE IPL state
RDMA/hns: Fixs hw access invalid dma memory error
PCI: mobiveil: Remove the flag MSI_FLAG_MULTI_PCI_MSI
PCI: mobiveil: Fix devfn check in mobiveil_pcie_valid_device()
PCI: mobiveil: Fix the valid check for inbound and outbound windows
ceph: fix "ceph.dir.rctime" vxattr value
net: pasemi: fix an use-after-free in pasemi_mac_phy_init()
net/tls: fix socket wmem accounting on fallback with netem
x86/pgtable/32: Fix LOWMEM_PAGES constant
xdp: fix possible cq entry leak
ARM: stm32: use "depends on" instead of "if" after prompt
scsi: libfc: fix null pointer dereference on a null lport
xfrm interface: ifname may be wrong in logs
drm/panel: make drm_panel.h self-contained
clk: sunxi-ng: v3s: add the missing PLL_DDR1
PM: sleep: Fix possible overflow in pm_system_cancel_wakeup()
libertas_tf: Use correct channel range in lbtf_geo_init
qed: reduce maximum stack frame size
usb: host: xhci-hub: fix extra endianness conversion
media: rcar-vin: Clean up correct notifier in error path
mic: avoid statically declaring a 'struct device'.
x86/kgbd: Use NMI_VECTOR not APIC_DM_NMI
crypto: ccp - Reduce maximum stack usage
ALSA: aoa: onyx: always initialize register read value
arm64: dts: renesas: r8a77995: Fix register range of display node
tipc: reduce risk of wakeup queue starvation
ARM: dts: stm32: add missing vdda-supply to adc on stm32h743i-eval
net/mlx5: Fix mlx5_ifc_query_lag_out_bits
cifs: fix rmmod regression in cifs.ko caused by force_sig changes
iio: tsl2772: Use devm_add_action_or_reset for tsl2772_chip_off
net: fix bpf_xdp_adjust_head regression for generic-XDP
spi: bcm-qspi: Fix BSPI QUAD and DUAL mode support when using flex mode
cxgb4: smt: Add lock for atomic_dec_and_test
crypto: caam - free resources in case caam_rng registration failed
ext4: set error return correctly when ext4_htree_store_dirent fails
RDMA/hns: Bugfix for slab-out-of-bounds when unloading hip08 driver
RDMA/hns: bugfix for slab-out-of-bounds when loading hip08 driver
ASoC: es8328: Fix copy-paste error in es8328_right_line_controls
ASoC: cs4349: Use PM ops 'cs4349_runtime_pm'
ASoC: wm8737: Fix copy-paste error in wm8737_snd_controls
net/rds: Add a few missing rds_stat_names entries
tools: bpftool: fix arguments for p_err() in do_event_pipe()
tools: bpftool: fix format strings and arguments for jsonw_printf()
drm: rcar-du: lvds: Fix bridge_to_rcar_lvds
bnxt_en: Fix handling FRAG_ERR when NVM_INSTALL_UPDATE cmd fails
signal: Allow cifs and drbd to receive their terminating signals
powerpc/64s/radix: Fix memory hot-unplug page table split
ASoC: sun4i-i2s: RX and TX counter registers are swapped
dmaengine: dw: platform: Switch to acpi_dma_controller_register()
rtc: rv3029: revert error handling patch to rv3029_eeprom_write()
mac80211: minstrel_ht: fix per-group max throughput rate initialization
i40e: reduce stack usage in i40e_set_fc
media: atmel: atmel-isi: fix timeout value for stop streaming
ARM: 8896/1: VDSO: Don't leak kernel addresses
rtc: pcf2127: bugfix: read rtc disables watchdog
mips: avoid explicit UB in assignment of mips_io_port_base
media: em28xx: Fix exception handling in em28xx_alloc_urbs()
iommu/mediatek: Fix iova_to_phys PA start for 4GB mode
ahci: Do not export local variable ahci_em_messages
rxrpc: Fix lack of conn cleanup when local endpoint is cleaned up [ver #2]
Partially revert "kfifo: fix kfifo_alloc() and kfifo_init()"
hwmon: (lm75) Fix write operations for negative temperatures
net/sched: cbs: Set default link speed to 10 Mbps in cbs_set_port_rate
power: supply: Init device wakeup after device_add()
x86, perf: Fix the dependency of the x86 insn decoder selftest
staging: greybus: light: fix a couple double frees
irqdomain: Add the missing assignment of domain->fwnode for named fwnode
bcma: fix incorrect update of BCMA_CORE_PCI_MDIO_DATA
usb: typec: tps6598x: Fix build error without CONFIG_REGMAP_I2C
bcache: Fix an error code in bch_dump_read()
iio: dac: ad5380: fix incorrect assignment to val
netfilter: ctnetlink: honor IPS_OFFLOAD flag
ath9k: dynack: fix possible deadlock in ath_dynack_node_{de}init
wcn36xx: use dynamic allocation for large variables
tty: serial: fsl_lpuart: Use appropriate lpuart32_* I/O funcs
ARM: dts: aspeed-g5: Fixe gpio-ranges upper limit
xsk: avoid store-tearing when assigning queues
xsk: avoid store-tearing when assigning umem
led: triggers: Fix dereferencing of null pointer
net: sonic: return NETDEV_TX_OK if failed to map buffer
net: hns3: fix error VF index when setting VLAN offload
rtlwifi: Fix file release memory leak
ARM: dts: logicpd-som-lv: Fix i2c2 and i2c3 Pin mux
f2fs: fix wrong error injection path in inc_valid_block_count()
f2fs: fix error path of f2fs_convert_inline_page()
scsi: fnic: fix msix interrupt allocation
Btrfs: fix hang when loading existing inode cache off disk
Btrfs: fix inode cache waiters hanging on failure to start caching thread
Btrfs: fix inode cache waiters hanging on path allocation failure
btrfs: use correct count in btrfs_file_write_iter()
ixgbe: sync the first fragment unconditionally
hwmon: (shtc1) fix shtc1 and shtw1 id mask
net: sonic: replace dev_kfree_skb in sonic_send_packet
pinctrl: iproc-gpio: Fix incorrect pinconf configurations
gpio/aspeed: Fix incorrect number of banks
ath10k: adjust skb length in ath10k_sdio_mbox_rx_packet
RDMA/cma: Fix false error message
net/rds: Fix 'ib_evt_handler_call' element in 'rds_ib_stat_names'
um: Fix off by one error in IRQ enumeration
bnxt_en: Increase timeout for HWRM_DBG_COREDUMP_XX commands
f2fs: fix to avoid accessing uninitialized field of inode page in is_alive()
mailbox: qcom-apcs: fix max_register value
clk: actions: Fix factor clk struct member access
powerpc/mm/mce: Keep irqs disabled during lockless page table walk
bpf: fix BTF limits
crypto: hisilicon - Matching the dma address for dma_pool_free()
iommu/amd: Wait for completion of IOTLB flush in attach_device
net: aquantia: Fix aq_vec_isr_legacy() return value
cxgb4: Signedness bug in init_one()
net: hisilicon: Fix signedness bug in hix5hd2_dev_probe()
net: broadcom/bcmsysport: Fix signedness in bcm_sysport_probe()
net: netsec: Fix signedness bug in netsec_probe()
net: socionext: Fix a signedness bug in ave_probe()
net: stmmac: dwmac-meson8b: Fix signedness bug in probe
net: axienet: fix a signedness bug in probe
of: mdio: Fix a signedness bug in of_phy_get_and_connect()
net: nixge: Fix a signedness bug in nixge_probe()
net: ethernet: stmmac: Fix signedness bug in ipq806x_gmac_of_parse()
net: sched: cbs: Avoid division by zero when calculating the port rate
nvme: retain split access workaround for capability reads
net: stmmac: gmac4+: Not all Unicast addresses may be available
rxrpc: Fix trace-after-put looking at the put connection record
mac80211: accept deauth frames in IBSS mode
llc: fix another potential sk_buff leak in llc_ui_sendmsg()
llc: fix sk_buff refcounting in llc_conn_state_process()
ip6erspan: remove the incorrect mtu limit for ip6erspan
net: stmmac: fix length of PTP clock's name string
net: stmmac: fix disabling flexible PPS output
sctp: add chunks to sk_backlog when the newsk sk_socket is not set
s390/qeth: Fix error handling during VNICC initialization
s390/qeth: Fix initialization of vnicc cmd masks during set online
act_mirred: Fix mirred_init_module error handling
net: avoid possible false sharing in sk_leave_memory_pressure()
net: add {READ|WRITE}_ONCE() annotations on ->rskq_accept_head
tcp: annotate lockless access to tcp_memory_pressure
net/smc: receive returns without data
net/smc: receive pending data after RCV_SHUTDOWN
drm/msm/dsi: Implement reset correctly
vhost/test: stop device before reset
dmaengine: imx-sdma: fix size check for sdma script_number
firmware: dmi: Fix unlikely out-of-bounds read in save_mem_devices
arm64: hibernate: check pgd table allocation
net: netem: fix error path for corrupted GSO frames
net: netem: correct the parent's backlog when corrupted packet was dropped
xsk: Fix registration of Rx-only sockets
bpf, offload: Unlock on error in bpf_offload_dev_create()
afs: Fix missing timeout reset
net: qca_spi: Move reset_count to struct qcaspi
hv_netvsc: Fix offset usage in netvsc_send_table()
hv_netvsc: Fix send_table offset in case of a host bug
afs: Fix large file support
drm: panel-lvds: Potential Oops in probe error handling
hwrng: omap3-rom - Fix missing clock by probing with device tree
dpaa_eth: perform DMA unmapping before read
dpaa_eth: avoid timestamp read on error paths
MIPS: Loongson: Fix return value of loongson_hwmon_init
hv_netvsc: flag software created hash value
net: neigh: use long type to store jiffies delta
packet: fix data-race in fanout_flow_is_huge()
i2c: stm32f7: report dma error during probe
mmc: sdio: fix wl1251 vendor id
mmc: core: fix wl1251 sdio quirks
affs: fix a memory leak in affs_remount
afs: Remove set but not used variables 'before', 'after'
dmaengine: ti: edma: fix missed failure handling
drm/radeon: fix bad DMA from INTERRUPT_CNTL2
arm64: dts: juno: Fix UART frequency
samples/bpf: Fix broken xdp_rxq_info due to map order assumptions
usb: dwc3: Allow building USB_DWC3_QCOM without EXTCON
IB/iser: Fix dma_nents type definition
serial: stm32: fix clearing interrupt error flags
arm64: dts: meson-gxm-khadas-vim2: fix uart_A bluetooth node
m68k: Call timer_interrupt() with interrupts disabled
Linux 4.19.99
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
Change-Id: Ieabeab79ea5c8cb4b6b1552702fa5d6100cea5db
[ Upstream commit 33da8e7c814f77310250bb54a9db36a44c5de784 ]
My recent to change to only use force_sig for a synchronous events
wound up breaking signal reception cifs and drbd. I had overlooked
the fact that by default kthreads start out with all signals set to
SIG_IGN. So a change I thought was safe turned out to have made it
impossible for those kernel thread to catch their signals.
Reverting the work on force_sig is a bad idea because what the code
was doing was very much a misuse of force_sig. As the way force_sig
ultimately allowed the signal to happen was to change the signal
handler to SIG_DFL. Which after the first signal will allow userspace
to send signals to these kernel threads. At least for
wake_ack_receiver in drbd that does not appear actively wrong.
So correct this problem by adding allow_kernel_signal that will allow
signals whose siginfo reports they were sent by the kernel through,
but will not allow userspace generated signals, and update cifs and
drbd to call allow_kernel_signal in an appropriate place so that their
thread can receive this signal.
Fixing things this way ensures that userspace won't be able to send
signals and cause problems, that it is clear which signals the
threads are expecting to receive, and it guarantees that nothing
else in the system will be affected.
This change was partly inspired by similar cifs and drbd patches that
added allow_signal.
Reported-by: ronnie sahlberg <ronniesahlberg@gmail.com>
Reported-by: Christoph Böhmwalder <christoph.boehmwalder@linbit.com>
Tested-by: Christoph Böhmwalder <christoph.boehmwalder@linbit.com>
Cc: Steve French <smfrench@gmail.com>
Cc: Philipp Reisner <philipp.reisner@linbit.com>
Cc: David Laight <David.Laight@ACULAB.COM>
Fixes: 247bc9470b1e ("cifs: fix rmmod regression in cifs.ko caused by force_sig changes")
Fixes: 72abe3bcf091 ("signal/cifs: Fix cifs_put_tcp_session to call send_sig instead of force_sig")
Fixes: fee109901f39 ("signal/drbd: Use send_sig not force_sig")
Fixes: 3cf5d076fb4d ("signal: Remove task parameter from force_sig")
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
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Merge 4.19.85 into android-4.19
Changes in 4.19.85
KVM: x86: introduce is_pae_paging
MIPS: BCM63XX: fix switch core reset on BCM6368
scsi: core: Handle drivers which set sg_tablesize to zero
ax88172a: fix information leak on short answers
ipmr: Fix skb headroom in ipmr_get_route().
net: gemini: add missed free_netdev
net: usb: qmi_wwan: add support for Foxconn T77W968 LTE modules
slip: Fix memory leak in slip_open error path
ALSA: usb-audio: Fix missing error check at mixer resolution test
ALSA: usb-audio: not submit urb for stopped endpoint
ALSA: usb-audio: Fix incorrect NULL check in create_yamaha_midi_quirk()
ALSA: usb-audio: Fix incorrect size check for processing/extension units
Btrfs: fix log context list corruption after rename exchange operation
Input: ff-memless - kill timer in destroy()
Input: synaptics-rmi4 - fix video buffer size
Input: synaptics-rmi4 - disable the relative position IRQ in the F12 driver
Input: synaptics-rmi4 - do not consume more data than we have (F11, F12)
Input: synaptics-rmi4 - clear IRQ enables for F54
Input: synaptics-rmi4 - destroy F54 poller workqueue when removing
IB/hfi1: Ensure full Gen3 speed in a Gen4 system
IB/hfi1: Use a common pad buffer for 9B and 16B packets
i2c: acpi: Force bus speed to 400KHz if a Silead touchscreen is present
ecryptfs_lookup_interpose(): lower_dentry->d_inode is not stable
ecryptfs_lookup_interpose(): lower_dentry->d_parent is not stable either
net: ethernet: dwmac-sun8i: Use the correct function in exit path
iommu/vt-d: Fix QI_DEV_IOTLB_PFSID and QI_DEV_EIOTLB_PFSID macros
mm: mempolicy: fix the wrong return value and potential pages leak of mbind
mm: memcg: switch to css_tryget() in get_mem_cgroup_from_mm()
mm: hugetlb: switch to css_tryget() in hugetlb_cgroup_charge_cgroup()
mmc: sdhci-of-at91: fix quirk2 overwrite
iio: adc: max9611: explicitly cast gain_selectors
tee: optee: take DT status property into account
ath10k: fix kernel panic by moving pci flush after napi_disable
iio: dac: mcp4922: fix error handling in mcp4922_write_raw
clk: sunxi-ng: h6: fix PWM gate/reset offset
soundwire: Initialize completion for defer messages
soundwire: intel: Fix uninitialized adev deref
arm64: dts: allwinner: a64: Orange Pi Win: Fix SD card node
arm64: dts: allwinner: a64: Olinuxino: fix DRAM voltage
arm64: dts: allwinner: a64: NanoPi-A64: Fix DCDC1 voltage
ALSA: pcm: signedness bug in snd_pcm_plug_alloc()
soc/tegra: pmc: Fix pad voltage configuration for Tegra186
arm64: dts: tegra210-p2180: Correct sdmmc4 vqmmc-supply
y2038: make do_gettimeofday() and get_seconds() inline
ARM: dts: rcar: Correct SATA device sizes to 2 MiB
ARM: dts: at91/trivial: Fix USART1 definition for at91sam9g45
rtc: sysfs: fix NULL check in rtc_add_groups()
rtc: rv8803: fix the rv8803 id in the OF table
remoteproc/davinci: Use %zx for formating size_t
extcon: cht-wc: Return from default case to avoid warnings
cfg80211: Avoid regulatory restore when COUNTRY_IE_IGNORE is set
ALSA: seq: Do error checks at creating system ports
ath10k: skip resetting rx filter for WCN3990
ath9k: fix tx99 with monitor mode interface
wil6210: drop Rx multicast packets that are looped-back to STA
wil6210: set edma variables only for Talyn-MB devices
wil6210: prevent usage of tx ring 0 for eDMA
wil6210: fix invalid memory access for rx_buff_mgmt debugfs
ath10k: limit available channels via DT ieee80211-freq-limit
ice: Update request resource command to latest specification
ice: Prevent control queue operations during reset
gfs2: Don't set GFS2_RDF_UPTODATE when the lvb is updated
ice: Fix and update driver version string
ASoC: dapm: Don't fail creating new DAPM control on NULL pinctrl
ASoC: dpcm: Properly initialise hw->rate_max
ASoC: meson: axg-fifo: report interrupt request failure
ASoC: AMD: Change MCLK to 48Mhz
pinctrl: ingenic: Probe driver at subsys_initcall
MIPS: BCM47XX: Enable USB power on Netgear WNDR3400v3
ARM: dts: exynos: Use i2c-gpio for HDMI-DDC on Arndale
ARM: dts: exynos: Fix HDMI-HPD line handling on Arndale
ARM: dts: exynos: Fix sound in Snow-rev5 Chromebook
liquidio: fix race condition in instruction completion processing
arm64: dts: stratix10: i2c clock running out of spec
ARM: dts: exynos: Fix regulators configuration on Peach Pi/Pit Chromebooks
i40evf: Validate the number of queues a PF sends
i40e: use correct length for strncpy
i40evf: set IFF_UNICAST_FLT flag for the VF
i40e: Check and correct speed values for link on open
i40evf: Don't enable vlan stripping when rx offload is turned on
i40e: hold the rtnl lock on clearing interrupt scheme
i40evf: cancel workqueue sync for adminq when a VF is removed
i40e: Prevent deleting MAC address from VF when set by PF
IB/rxe: avoid back-to-back retries
IB/rxe: fixes for rdma read retry
iwlwifi: drop packets with bad status in CD
iwlwifi: don't WARN on trying to dump dead firmware
iwlwifi: mvm: avoid sending too many BARs
media: vicodec: fix out-of-range values when decoding
media: i2c: Fix pm_runtime_get_if_in_use() usage in sensor drivers
media: ov772x: Disable clk on error path
ARM: dts: pxa: fix the rtc controller
ARM: dts: pxa: fix power i2c base address
rtl8187: Fix warning generated when strncpy() destination length matches the sixe argument
mwifiex: do no submit URB in suspended state
mwifex: free rx_cmd skb in suspended state
brcmfmac: fix wrong strnchr usage
mt76: Fix comparisons with invalid hardware key index
soc: imx: gpc: fix PDN delay
ASoC: rsnd: ssi: Fix issue in dma data address assignment
net: hns3: Fix for multicast failure
net: hns3: Fix error of checking used vlan id
net: hns3: Fix for loopback selftest failed problem
net: hns3: Change the dst mac addr of loopback packet
net/mlx5: Fix atomic_mode enum values
net: phy: mscc: read 'vsc8531,vddmac' as an u32
net: phy: mscc: read 'vsc8531, edge-slowdown' as an u32
ARM: dts: meson8: fix the clock controller register size
ARM: dts: meson8b: fix the clock controller register size
mtd: rawnand: marvell: use regmap_update_bits() for syscon access
mtd: rawnand: fsl_ifc: check result of SRAM initialization
mtd: rawnand: fsl_ifc: fixup SRAM init for newer ctrl versions
mtd: rawnand: qcom: don't include dma-direct.h
IB/mlx5: Change TX affinity assignment in RoCE LAG mode
qxl: fix null-pointer crash during suspend
mac80211: fix saving a few HE values
cfg80211: validate wmm rule when setting
f2fs: avoid wrong decrypted data from disk
net: lan78xx: Bail out if lan78xx_get_endpoints fails
rtnetlink: move type calculation out of loop
ASoC: sgtl5000: avoid division by zero if lo_vag is zero
ath10k: avoid possible memory access violation
ARM: dts: exynos: Disable pull control for S5M8767 PMIC
ath10k: wmi: disable softirq's while calling ieee80211_rx
i2c: mediatek: Use DMA safe buffers for i2c transactions
IB/mlx5: Don't hold spin lock while checking device state
IB/ipoib: Ensure that MTU isn't less than minimum permitted
RDMA/core: Rate limit MAD error messages
RDMA/core: Follow correct unregister order between sysfs and cgroup
mips: txx9: fix iounmap related issue
udf: Fix crash during mount
ASoC: dapm: Avoid uninitialised variable warning
ASoC: Intel: hdac_hdmi: Limit sampling rates at dai creation
ata: Disable AHCI ALPM feature for Ampere Computing eMAG SATA
of: make PowerMac cache node search conditional on CONFIG_PPC_PMAC
ARM: dts: omap3-gta04: give spi_lcd node a label so that we can overwrite in other DTS files
ARM: dts: omap3-gta04: fixes for tvout / venc
ARM: dts: omap3-gta04: tvout: enable as display1 alias
ARM: dts: omap3-gta04: fix touchscreen tsc2007
ARM: dts: omap3-gta04: make NAND partitions compatible with recent U-Boot
ARM: dts: omap3-gta04: keep vpll2 always on
f2fs: submit bio after shutdown
failover: Fix error return code in net_failover_create
sched/debug: Explicitly cast sched_feat() to bool
sched/debug: Use symbolic names for task state constants
firmware: arm_scmi: use strlcpy to ensure NULL-terminated strings
arm64: dts: rockchip: Fix VCC5V0_HOST_EN on rk3399-sapphire
ARM: dts: exynos: Disable pull control for PMIC IRQ line on Artik5 board
usb: mtu3: disable vbus rise/fall interrupts of ltssm
dmaengine: dma-jz4780: Don't depend on MACH_JZ4780
dmaengine: dma-jz4780: Further residue status fix
EDAC, sb_edac: Return early on ADDRV bit and address type test
rtc: mt6397: fix possible race condition
rtc: pl030: fix possible race condition
ath9k: add back support for using active monitor interfaces for tx99
dmaengine: at_xdmac: remove a stray bottom half unlock
RDMA/hns: Fix an error code in hns_roce_v2_init_eq_table()
IB/hfi1: Missing return value in error path for user sdma
signal: Always ignore SIGKILL and SIGSTOP sent to the global init
signal: Properly deliver SIGILL from uprobes
signal: Properly deliver SIGSEGV from x86 uprobes
f2fs: fix memory leak of write_io in fill_super()
f2fs: fix memory leak of percpu counter in fill_super()
f2fs: fix setattr project check upon fssetxattr ioctl
scsi: qla2xxx: Use correct qpair for ABTS/CMD
scsi: qla2xxx: Fix iIDMA error
scsi: qla2xxx: Defer chip reset until target mode is enabled
scsi: qla2xxx: Terminate Plogi/PRLI if WWN is 0
scsi: qla2xxx: Fix deadlock between ATIO and HW lock
scsi: qla2xxx: Increase abort timeout value
scsi: qla2xxx: Check for Register disconnect
scsi: qla2xxx: Fix port speed display on chip reset
scsi: qla2xxx: Fix dropped srb resource.
scsi: qla2xxx: Fix duplicate switch's Nport ID entries
scsi: lpfc: Fix GFT_ID and PRLI logic for RSCN
scsi: lpfc: Correct invalid EQ doorbell write on if_type=6
scsi: lpfc: Fix errors in log messages.
scsi: sym53c8xx: fix NULL pointer dereference panic in sym_int_sir()
ARM: imx6: register pm_power_off handler if "fsl,pmic-stby-poweroff" is set
scsi: pm80xx: Corrected dma_unmap_sg() parameter
scsi: pm80xx: Fixed system hang issue during kexec boot
kprobes: Don't call BUG_ON() if there is a kprobe in use on free list
net: aquantia: fix hw_atl_utils_fw_upload_dwords
Drivers: hv: vmbus: Fix synic per-cpu context initialization
nvmem: core: return error code instead of NULL from nvmem_device_get
media: dt-bindings: adv748x: Fix decimal unit addresses
ALSA: hda: Fix implicit definition of pci_iomap() on SH
media: fix: media: pci: meye: validate offset to avoid arbitrary access
media: dvb: fix compat ioctl translation
net: bcmgenet: Fix speed selection for reverse MII
arm64: dts: meson: libretech: update board model
arm64: dts: meson-axg: use the proper compatible for ethmac
ALSA: intel8x0m: Register irq handler after register initializations
arm64: dts: renesas: salvator-common: adv748x: Override secondary addresses
arm64: dts: renesas: r8a77965: Attach the SYS-DMAC to the IPMMU
arm64: dts: renesas: r8a77965: Fix HS-USB compatible
arm64: dts: renesas: r8a77965: Fix clock/reset for usb2_phy1
pinctrl: at91-pio4: fix has_config check in atmel_pctl_dt_subnode_to_map()
llc: avoid blocking in llc_sap_close()
ARM: dts: qcom: ipq4019: fix cpu0's qcom,saw2 reg value
soc: qcom: geni: Don't ignore clk_round_rate() errors in geni_se_clk_tbl_get()
soc: qcom: geni: geni_se_clk_freq_match() should always accept multiples
soc: qcom: wcnss_ctrl: Avoid string overflow
soc: qcom: apr: Avoid string overflow
drivers: qcom: rpmh-rsc: clear wait_for_compl after use
arm64: dts: broadcom: Fix I2C and SPI bus warnings
ARM: dts: bcm: Fix SPI bus warnings
ARM: dts: aspeed: Fix I2C bus warnings
powerpc/vdso: Correct call frame information
ARM: dts: socfpga: Fix I2C bus unit-address error
ARM: dts: sunxi: Fix I2C bus warnings
pinctrl: at91: don't use the same irqchip with multiple gpiochips
ARM: dts: sun9i: Fix I2C bus warnings
android: binder: no outgoing transaction when thread todo has transaction
cxgb4: Fix endianness issue in t4_fwcache()
arm64: fix for bad_mode() handler to always result in panic
block, bfq: inject other-queue I/O into seeky idle queues on NCQ flash
blok, bfq: do not plug I/O if all queues are weight-raised
arm64: dts: meson: Fix erroneous SPI bus warnings
power: supply: ab8500_fg: silence uninitialized variable warnings
power: reset: at91-poweroff: do not procede if at91_shdwc is allocated
power: supply: max8998-charger: Fix platform data retrieval
component: fix loop condition to call unbind() if bind() fails
kernfs: Fix range checks in kernfs_get_target_path
ip_gre: fix parsing gre header in ipgre_err
scsi: ufshcd: Fix NULL pointer dereference for in ufshcd_init
ARM: dts: rockchip: Fix erroneous SPI bus dtc warnings on rk3036
arm64: dts: rockchip: Fix I2C bus unit-address error on rk3399-puma-haikou
ACPI / LPSS: Exclude I2C busses shared with PUNIT from pmc_atom_d3_mask
netfilter: nf_tables: avoid BUG_ON usage
ath9k: Fix a locking bug in ath9k_add_interface()
s390/qeth: uninstall IRQ handler on device removal
s390/qeth: invoke softirqs after napi_schedule()
media: vsp1: Fix vsp1_regs.h license header
media: vsp1: Fix YCbCr planar formats pitch calculation
media: ov2680: don't register the v4l2 subdevice before checking chip ID
PCI/ACPI: Correct error message for ASPM disabling
net: socionext: Fix two sleep-in-atomic-context bugs in ave_rxfifo_reset()
PCI: mediatek: Fix unchecked return value
ARM: dts: xilinx: Fix I2C and SPI bus warnings
serial: uartps: Fix suspend functionality
serial: samsung: Enable baud clock for UART reset procedure in resume
serial: mxs-auart: Fix potential infinite loop
tty: serial: qcom_geni_serial: Fix serial when not used as console
arm64: dts: ti: k3-am65: Change #address-cells and #size-cells of interconnect to 2
samples/bpf: fix a compilation failure
spi/bcm63xx-hsspi: keep pll clk enabled
spi: mediatek: Don't modify spi_transfer when transfer.
ASoC: rt5682: Fix the boost volume at the begining of playback
ipmi_si_pci: fix NULL device in ipmi_si error message
ipmi_si: fix potential integer overflow on large shift
ipmi:dmi: Ignore IPMI SMBIOS entries with a zero base address
ipmi: fix return value of ipmi_set_my_LUN
net: hns3: fix return type of ndo_start_xmit function
net: cavium: fix return type of ndo_start_xmit function
net: ibm: fix return type of ndo_start_xmit function
powerpc/iommu: Avoid derefence before pointer check
selftests/powerpc: Do not fail with reschedule
powerpc/64s/hash: Fix stab_rr off by one initialization
powerpc/pseries/memory-hotplug: Only update DT once per memory DLPAR request
powerpc/pseries: Disable CPU hotplug across migrations
powerpc: Fix duplicate const clang warning in user access code
RDMA/i40iw: Fix incorrect iterator type
ARM: dts: atmel: Fix I2C and SPI bus warnings
OPP: Protect dev_list with opp_table lock
of/unittest: Fix I2C bus unit-address error
libfdt: Ensure INT_MAX is defined in libfdt_env.h
power: supply: twl4030_charger: fix charging current out-of-bounds
power: supply: twl4030_charger: disable eoc interrupt on linear charge
net: mvpp2: fix the number of queues per cpu for PPv2.2
net: marvell: fix return type of ndo_start_xmit function
net: toshiba: fix return type of ndo_start_xmit function
net: xilinx: fix return type of ndo_start_xmit function
net: broadcom: fix return type of ndo_start_xmit function
net: amd: fix return type of ndo_start_xmit function
net: sun: fix return type of ndo_start_xmit function
net: hns3: Fix for setting speed for phy failed problem
net: hns3: Fix cmdq registers initialization issue for vf
net: hns3: Clear client pointer when initialize client failed or unintialize finished
net: hns3: Fix client initialize state issue when roce client initialize failed
net: hns3: Fix parameter type for q_id in hclge_tm_q_to_qs_map_cfg()
nfp: provide a better warning when ring allocation fails
usb: chipidea: imx: enable OTG overcurrent in case USB subsystem is already started
usb: chipidea: Fix otg event handler
usb: usbtmc: Fix ioctl USBTMC_IOCTL_ABORT_BULK_OUT
s390/zcrypt: enable AP bus scan without a valid default domain
s390/vdso: avoid 64-bit vdso mapping for compat tasks
s390/vdso: correct CFI annotations of vDSO functions
brcmfmac: increase buffer for obtaining firmware capabilities
brcmsmac: Use kvmalloc() for ucode allocations
mlxsw: spectrum: Init shaper for TCs 8..15
PCI: portdrv: Initialize service drivers directly
ARM: dts: am335x-evm: fix number of cpsw
ARM: dts: ti: Fix SPI and I2C bus warnings
f2fs: avoid infinite loop in f2fs_alloc_nid
f2fs: fix to recover inode's uid/gid during POR
ARM: dts: ux500: Correct SCU unit address
ARM: dts: ux500: Fix LCDA clock line muxing
ARM: dts: ste: Fix SPI controller node names
spi: pic32: Use proper enum in dmaengine_prep_slave_rg
crypto: chacha20 - Fix chacha20_block() keystream alignment (again)
cpufeature: avoid warning when compiling with clang
crypto: arm/crc32 - avoid warning when compiling with Clang
ARM: dts: marvell: Fix SPI and I2C bus warnings
x86/mce-inject: Reset injection struct after injection
ARM: dts: stm32: enable display on stm32mp157c-ev1 board
ARM: dts: clearfog: fix sdhci supply property name
ARM: dts: stm32: Fix SPI controller node names
bnx2x: Ignore bandwidth attention in single function mode
PCI/AER: Take reference on error devices
PCI/AER: Don't read upstream ports below fatal errors
PCI/ERR: Use slot reset if available
samples/bpf: fix compilation failure
net: phy: mdio-bcm-unimac: Allow configuring MDIO clock divider
net: micrel: fix return type of ndo_start_xmit function
net: freescale: fix return type of ndo_start_xmit function
x86/CPU: Use correct macros for Cyrix calls
x86/CPU: Change query logic so CPUID is enabled before testing
EDAC: Correct DIMM capacity unit symbol
MIPS: kexec: Relax memory restriction
arm64: dts: rockchip: Fix microSD in rk3399 sapphire board
mlxsw: Make MLXSW_SP1_FWREV_MINOR a hard requirement
media: imx: work around false-positive warning, again
media: pci: ivtv: Fix a sleep-in-atomic-context bug in ivtv_yuv_init()
media: au0828: Fix incorrect error messages
media: davinci: Fix implicit enum conversion warning
ARM: dts: rockchip: explicitly set vcc_sd0 pin to gpio on rk3188-radxarock
usb: gadget: uvc: configfs: Drop leaked references to config items
usb: gadget: uvc: configfs: Prevent format changes after linking header
usb: gadget: uvc: configfs: Sort frame intervals upon writing
ARM: dts: exynos: Correct audio subsystem parent clock on Peach Chromebooks
i2c: aspeed: fix invalid clock parameters for very large divisors
gpiolib: Fix gpio_direction_* for single direction GPIOs
ARM: at91: pm: call put_device instead of of_node_put in at91_pm_config_ws
phy: brcm-sata: allow PHY_BRCM_SATA driver to be built for DSL SoCs
phy: renesas: rcar-gen3-usb2: fix vbus_ctrl for role sysfs
phy: phy-twl4030-usb: fix denied runtime access
ARM: dts: imx6ull: update vdd_soc voltage for 900MHz operating point
usb: gadget: uvc: Factor out video USB request queueing
usb: gadget: uvc: Only halt video streaming endpoint in bulk mode
coresight: Use ERR_CAST instead of ERR_PTR
coresight: Fix handling of sinks
coresight: perf: Fix per cpu path management
coresight: perf: Disable trace path upon source error
coresight: tmc-etr: Handle driver mode specific ETR buffers
coresight: etm4x: Configure EL2 exception level when kernel is running in HYP
coresight: tmc: Fix byte-address alignment for RRP
coresight: dynamic-replicator: Handle multiple connections
slimbus: ngd: register ngd driver only once.
slimbus: ngd: return proper error code instead of zero
silmbus: ngd: register controller after power up.
misc: kgdbts: Fix restrict error
misc: genwqe: should return proper error value.
vmbus: keep pointer to ring buffer page
vfio/pci: Fix potential memory leak in vfio_msi_cap_len
vfio/pci: Mask buggy SR-IOV VF INTx support
iw_cxgb4: Use proper enumerated type in c4iw_bar2_addrs
scsi: libsas: always unregister the old device if going to discover new
f2fs: fix remount problem of option io_bits
phy: lantiq: Fix compile warning
arm64: dts: fsl: Fix I2C and SPI bus warnings
ARM: dts: imx51-zii-rdu1: Fix the rtc compatible string
arm64: tegra: I2C on Tegra194 is not compatible with Tegra114
ARM: dts: tegra30: fix xcvr-setup-use-fuses
ARM: dts: tegra20: restore address order
ARM: tegra: apalis_t30: fix mmc1 cmd pull-up
ARM: tegra: apalis_t30: fix mcp2515 can controller interrupt polarity
ARM: tegra: colibri_t30: fix mcp2515 can controller interrupt polarity
ARM: dts: paz00: fix wakeup gpio keycode
net: smsc: fix return type of ndo_start_xmit function
net: faraday: fix return type of ndo_start_xmit function
PCI/ERR: Run error recovery callbacks for all affected devices
f2fs: update i_size after DIO completion
f2fs: fix to recover inode's project id during POR
f2fs: mark inode dirty explicitly in recover_inode()
RDMA: Fix dependencies for rdma_user_mmap_io
EDAC: Raise the maximum number of memory controllers
ARM: dts: realview: Fix SPI controller node names
firmware: dell_rbu: Make payload memory uncachable
Bluetooth: hci_serdev: clear HCI_UART_PROTO_READY to avoid closing proto races
Bluetooth: L2CAP: Detect if remote is not able to use the whole MPS
Bluetooth: btrsi: fix bt tx timeout issue
x86/hyperv: Suppress "PCI: Fatal: No config space access function found"
crypto: s5p-sss: Fix race in error handling
crypto: s5p-sss: Fix Fix argument list alignment
crypto: fix a memory leak in rsa-kcs1pad's encryption mode
iwlwifi: dbg: don't crash if the firmware crashes in the middle of a debug dump
iwlwifi: fix non_shared_ant for 22000 devices
iwlwifi: pcie: read correct prph address for newer devices
iwlwifi: api: annotate compressed BA notif array sizes
iwlwifi: pcie: gen2: build A-MSDU only for GSO
iwlwifi: pcie: fit reclaim msg to MAX_MSG_LEN
iwlwifi: mvm: use correct FIFO length
iwlwifi: mvm: Allow TKIP for AP mode
scsi: NCR5380: Clear all unissued commands on host reset
scsi: NCR5380: Have NCR5380_select() return a bool
scsi: NCR5380: Withhold disconnect privilege for REQUEST SENSE
scsi: NCR5380: Use DRIVER_SENSE to indicate valid sense data
scsi: NCR5380: Check for invalid reselection target
scsi: NCR5380: Don't clear busy flag when abort fails
scsi: NCR5380: Don't call dsprintk() following reselection interrupt
scsi: NCR5380: Handle BUS FREE during reselection
scsi: NCR5380: Check for bus reset
arm64: dts: amd: Fix SPI bus warnings
arm64: dts: lg: Fix SPI controller node names
ARM: dts: lpc32xx: Fix SPI controller node names
rtc: isl1208: avoid possible sysfs race
rtc: tx4939: fixup nvmem name and register size
rtc: armada38x: fix possible race condition
netfilter: masquerade: don't flush all conntracks if only one address deleted on device
usb: xhci-mtk: fix ISOC error when interval is zero
usb: usbtmc: uninitialized symbol 'actual' in usbtmc_ioctl_clear
fuse: use READ_ONCE on congestion_threshold and max_background
IB/iser: Fix possible NULL deref at iser_inv_desc()
media: ov2680: fix null dereference at power on
s390/vdso: correct vdso mapping for compat tasks
net: phy: mdio-bcm-unimac: mark PM functions as __maybe_unused
memfd: Use radix_tree_deref_slot_protected to avoid the warning.
slcan: Fix memory leak in error path
Linux 4.19.85
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
Change-Id: I0857e66ee2cdd412cd736548a1395bf764a8ab0a
[ Upstream commit 86989c41b5ea08776c450cb759592532314a4ed6 ]
If the first process started (aka /sbin/init) receives a SIGKILL it
will panic the system if it is delivered. Making the system unusable
and undebugable. It isn't much better if the first process started
receives SIGSTOP.
So always ignore SIGSTOP and SIGKILL sent to init.
This is done in a separate clause in sig_task_ignored as force_sig_info
can clear SIG_UNKILLABLE and this protection should work even then.
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
This patch adds polling support to pidfd.
Android low memory killer (LMK) needs to know when a process dies once
it is sent the kill signal. It does so by checking for the existence of
/proc/pid which is both racy and slow. For example, if a PID is reused
between when LMK sends a kill signal and checks for existence of the
PID, since the wrong PID is now possibly checked for existence.
Using the polling support, LMK will be able to get notified when a process
exists in race-free and fast way, and allows the LMK to do other things
(such as by polling on other fds) while awaiting the process being killed
to die.
For notification to polling processes, we follow the same existing
mechanism in the kernel used when the parent of the task group is to be
notified of a child's death (do_notify_parent). This is precisely when the
tasks waiting on a poll of pidfd are also awakened in this patch.
We have decided to include the waitqueue in struct pid for the following
reasons:
1. The wait queue has to survive for the lifetime of the poll. Including
it in task_struct would not be option in this case because the task can
be reaped and destroyed before the poll returns.
2. By including the struct pid for the waitqueue means that during
de_thread(), the new thread group leader automatically gets the new
waitqueue/pid even though its task_struct is different.
Appropriate test cases are added in the second patch to provide coverage of
all the cases the patch is handling.
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Daniel Colascione <dancol@google.com>
Cc: Jann Horn <jannh@google.com>
Cc: Tim Murray <timmurray@google.com>
Cc: Jonathan Kowalski <bl0pbl33p@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Kees Cook <keescook@chromium.org>
Cc: David Howells <dhowells@redhat.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: kernel-team@android.com
Reviewed-by: Oleg Nesterov <oleg@redhat.com>
Co-developed-by: Daniel Colascione <dancol@google.com>
Signed-off-by: Daniel Colascione <dancol@google.com>
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Christian Brauner <christian@brauner.io>
(cherry picked from commit b53b0b9d9a613c418057f6cb921c2f40a6f78c24)
Bug: 135608568
Test: test program using syscall(__NR_sys_pidfd_open,..) and poll()
Change-Id: I0391acb666b34e33ef60a778dffdf12ed3654393
Signed-off-by: Suren Baghdasaryan <surenb@google.com>
Improve the comments for pidfd_send_signal().
First, the comment still referred to a file descriptor for a process as a
"task file descriptor" which stems from way back at the beginning of the
discussion. Replace this with "pidfd" for consistency.
Second, the wording for the explanation of the arguments to the syscall
was a bit inconsistent, e.g. some used the past tense some used present
tense. Make the wording more consistent.
Signed-off-by: Christian Brauner <christian@brauner.io>
(cherry picked from commit c732327f04a3818f35fa97d07b1d64d31b691d78)
Bug: 135608568
Test: test program using syscall(__NR_sys_pidfd_open,..) and poll()
Change-Id: Iaa289e1bc2f96366102e51241accbb97099553d4
Signed-off-by: Suren Baghdasaryan <surenb@google.com>
Let pidfd_send_signal() use pidfds retrieved via CLONE_PIDFD. With this
patch pidfd_send_signal() becomes independent of procfs. This fullfils
the request made when we merged the pidfd_send_signal() patchset. The
pidfd_send_signal() syscall is now always available allowing for it to
be used by users without procfs mounted or even users without procfs
support compiled into the kernel.
Signed-off-by: Christian Brauner <christian@brauner.io>
Co-developed-by: Jann Horn <jannh@google.com>
Signed-off-by: Jann Horn <jannh@google.com>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: David Howells <dhowells@redhat.com>
Cc: "Michael Kerrisk (man-pages)" <mtk.manpages@gmail.com>
Cc: Andy Lutomirsky <luto@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Aleksa Sarai <cyphar@cyphar.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
(cherry picked from commit 2151ad1b067275730de1b38c7257478cae47d29e)
Bug: 135608568
Test: test program using syscall(__NR_sys_pidfd_open,..) and poll()
Change-Id: If6ee59279f41e0ae3c6d9e24f7b5481f23aab469
Signed-off-by: Suren Baghdasaryan <surenb@google.com>
As stated in the original commit for pidfd_send_signal() we don't allow
to signal processes through O_PATH file descriptors since it is
semantically equivalent to a write on the pidfd.
We already correctly error out right now and return EBADF if an O_PATH
fd is passed. This is because we use file->f_op to detect whether a
pidfd is passed and O_PATH fds have their file->f_op set to empty_fops
in do_dentry_open() and thus fail the test.
Thus, there is no regression. It's just semantically correct to use
fdget() and return an error right from there instead of taking a
reference and returning an error later.
Signed-off-by: Christian Brauner <christian@brauner.io>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Jann Horn <jann@thejh.net>
Cc: David Howells <dhowells@redhat.com>
Cc: "Michael Kerrisk (man-pages)" <mtk.manpages@gmail.com>
Cc: Andy Lutomirsky <luto@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Aleksa Sarai <cyphar@cyphar.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
(cherry picked from commit 738a7832d21e3d911fcddab98ce260b79010b461)
Bug: 135608568
Test: test program using syscall(__NR_pidfd_send_signal,..) to send SIGKILL
Change-Id: Ib102922f9793e8610940d34ad5fb1256d4b07476
Signed-off-by: Suren Baghdasaryan <surenb@google.com>
The current sys_pidfd_send_signal() silently turns signals with explicit
SI_USER context that are sent to non-current tasks into signals with
kernel-generated siginfo.
This is unlike do_rt_sigqueueinfo(), which returns -EPERM in this case.
If a user actually wants to send a signal with kernel-provided siginfo,
they can do that with pidfd_send_signal(pidfd, sig, NULL, 0); so allowing
this case is unnecessary.
Instead of silently replacing the siginfo, just bail out with an error;
this is consistent with other interfaces and avoids special-casing behavior
based on security checks.
Fixes: 3eb39f47934f ("signal: add pidfd_send_signal() syscall")
Signed-off-by: Jann Horn <jannh@google.com>
Signed-off-by: Christian Brauner <christian@brauner.io>
(cherry picked from commit 556a888a14afe27164191955618990fb3ccc9aad)
Bug: 135608568
Test: test program using syscall(__NR_pidfd_send_signal,..) to send SIGKILL
Change-Id: I004452c19c50296730a2c6852a5ef47abd69d819
Signed-off-by: Suren Baghdasaryan <surenb@google.com>
The kill() syscall operates on process identifiers (pid). After a process
has exited its pid can be reused by another process. If a caller sends a
signal to a reused pid it will end up signaling the wrong process. This
issue has often surfaced and there has been a push to address this problem [1].
This patch uses file descriptors (fd) from proc/<pid> as stable handles on
struct pid. Even if a pid is recycled the handle will not change. The fd
can be used to send signals to the process it refers to.
Thus, the new syscall pidfd_send_signal() is introduced to solve this
problem. Instead of pids it operates on process fds (pidfd).
/* prototype and argument /*
long pidfd_send_signal(int pidfd, int sig, siginfo_t *info, unsigned int flags);
/* syscall number 424 */
The syscall number was chosen to be 424 to align with Arnd's rework in his
y2038 to minimize merge conflicts (cf. [25]).
In addition to the pidfd and signal argument it takes an additional
siginfo_t and flags argument. If the siginfo_t argument is NULL then
pidfd_send_signal() is equivalent to kill(<positive-pid>, <signal>). If it
is not NULL pidfd_send_signal() is equivalent to rt_sigqueueinfo().
The flags argument is added to allow for future extensions of this syscall.
It currently needs to be passed as 0. Failing to do so will cause EINVAL.
/* pidfd_send_signal() replaces multiple pid-based syscalls */
The pidfd_send_signal() syscall currently takes on the job of
rt_sigqueueinfo(2) and parts of the functionality of kill(2), Namely, when a
positive pid is passed to kill(2). It will however be possible to also
replace tgkill(2) and rt_tgsigqueueinfo(2) if this syscall is extended.
/* sending signals to threads (tid) and process groups (pgid) */
Specifically, the pidfd_send_signal() syscall does currently not operate on
process groups or threads. This is left for future extensions.
In order to extend the syscall to allow sending signal to threads and
process groups appropriately named flags (e.g. PIDFD_TYPE_PGID, and
PIDFD_TYPE_TID) should be added. This implies that the flags argument will
determine what is signaled and not the file descriptor itself. Put in other
words, grouping in this api is a property of the flags argument not a
property of the file descriptor (cf. [13]). Clarification for this has been
requested by Eric (cf. [19]).
When appropriate extensions through the flags argument are added then
pidfd_send_signal() can additionally replace the part of kill(2) which
operates on process groups as well as the tgkill(2) and
rt_tgsigqueueinfo(2) syscalls.
How such an extension could be implemented has been very roughly sketched
in [14], [15], and [16]. However, this should not be taken as a commitment
to a particular implementation. There might be better ways to do it.
Right now this is intentionally left out to keep this patchset as simple as
possible (cf. [4]).
/* naming */
The syscall had various names throughout iterations of this patchset:
- procfd_signal()
- procfd_send_signal()
- taskfd_send_signal()
In the last round of reviews it was pointed out that given that if the
flags argument decides the scope of the signal instead of different types
of fds it might make sense to either settle for "procfd_" or "pidfd_" as
prefix. The community was willing to accept either (cf. [17] and [18]).
Given that one developer expressed strong preference for the "pidfd_"
prefix (cf. [13]) and with other developers less opinionated about the name
we should settle for "pidfd_" to avoid further bikeshedding.
The "_send_signal" suffix was chosen to reflect the fact that the syscall
takes on the job of multiple syscalls. It is therefore intentional that the
name is not reminiscent of neither kill(2) nor rt_sigqueueinfo(2). Not the
fomer because it might imply that pidfd_send_signal() is a replacement for
kill(2), and not the latter because it is a hassle to remember the correct
spelling - especially for non-native speakers - and because it is not
descriptive enough of what the syscall actually does. The name
"pidfd_send_signal" makes it very clear that its job is to send signals.
/* zombies */
Zombies can be signaled just as any other process. No special error will be
reported since a zombie state is an unreliable state (cf. [3]). However,
this can be added as an extension through the @flags argument if the need
ever arises.
/* cross-namespace signals */
The patch currently enforces that the signaler and signalee either are in
the same pid namespace or that the signaler's pid namespace is an ancestor
of the signalee's pid namespace. This is done for the sake of simplicity
and because it is unclear to what values certain members of struct
siginfo_t would need to be set to (cf. [5], [6]).
/* compat syscalls */
It became clear that we would like to avoid adding compat syscalls
(cf. [7]). The compat syscall handling is now done in kernel/signal.c
itself by adding __copy_siginfo_from_user_generic() which lets us avoid
compat syscalls (cf. [8]). It should be noted that the addition of
__copy_siginfo_from_user_any() is caused by a bug in the original
implementation of rt_sigqueueinfo(2) (cf. 12).
With upcoming rework for syscall handling things might improve
significantly (cf. [11]) and __copy_siginfo_from_user_any() will not gain
any additional callers.
/* testing */
This patch was tested on x64 and x86.
/* userspace usage */
An asciinema recording for the basic functionality can be found under [9].
With this patch a process can be killed via:
#define _GNU_SOURCE
#include <errno.h>
#include <fcntl.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/stat.h>
#include <sys/syscall.h>
#include <sys/types.h>
#include <unistd.h>
static inline int do_pidfd_send_signal(int pidfd, int sig, siginfo_t *info,
unsigned int flags)
{
#ifdef __NR_pidfd_send_signal
return syscall(__NR_pidfd_send_signal, pidfd, sig, info, flags);
#else
return -ENOSYS;
#endif
}
int main(int argc, char *argv[])
{
int fd, ret, saved_errno, sig;
if (argc < 3)
exit(EXIT_FAILURE);
fd = open(argv[1], O_DIRECTORY | O_CLOEXEC);
if (fd < 0) {
printf("%s - Failed to open \"%s\"\n", strerror(errno), argv[1]);
exit(EXIT_FAILURE);
}
sig = atoi(argv[2]);
printf("Sending signal %d to process %s\n", sig, argv[1]);
ret = do_pidfd_send_signal(fd, sig, NULL, 0);
saved_errno = errno;
close(fd);
errno = saved_errno;
if (ret < 0) {
printf("%s - Failed to send signal %d to process %s\n",
strerror(errno), sig, argv[1]);
exit(EXIT_FAILURE);
}
exit(EXIT_SUCCESS);
}
/* Q&A
* Given that it seems the same questions get asked again by people who are
* late to the party it makes sense to add a Q&A section to the commit
* message so it's hopefully easier to avoid duplicate threads.
*
* For the sake of progress please consider these arguments settled unless
* there is a new point that desperately needs to be addressed. Please make
* sure to check the links to the threads in this commit message whether
* this has not already been covered.
*/
Q-01: (Florian Weimer [20], Andrew Morton [21])
What happens when the target process has exited?
A-01: Sending the signal will fail with ESRCH (cf. [22]).
Q-02: (Andrew Morton [21])
Is the task_struct pinned by the fd?
A-02: No. A reference to struct pid is kept. struct pid - as far as I
understand - was created exactly for the reason to not require to
pin struct task_struct (cf. [22]).
Q-03: (Andrew Morton [21])
Does the entire procfs directory remain visible? Just one entry
within it?
A-03: The same thing that happens right now when you hold a file descriptor
to /proc/<pid> open (cf. [22]).
Q-04: (Andrew Morton [21])
Does the pid remain reserved?
A-04: No. This patchset guarantees a stable handle not that pids are not
recycled (cf. [22]).
Q-05: (Andrew Morton [21])
Do attempts to signal that fd return errors?
A-05: See {Q,A}-01.
Q-06: (Andrew Morton [22])
Is there a cleaner way of obtaining the fd? Another syscall perhaps.
A-06: Userspace can already trivially retrieve file descriptors from procfs
so this is something that we will need to support anyway. Hence,
there's no immediate need to add another syscalls just to make
pidfd_send_signal() not dependent on the presence of procfs. However,
adding a syscalls to get such file descriptors is planned for a
future patchset (cf. [22]).
Q-07: (Andrew Morton [21] and others)
This fd-for-a-process sounds like a handy thing and people may well
think up other uses for it in the future, probably unrelated to
signals. Are the code and the interface designed to permit such
future applications?
A-07: Yes (cf. [22]).
Q-08: (Andrew Morton [21] and others)
Now I think about it, why a new syscall? This thing is looking
rather like an ioctl?
A-08: This has been extensively discussed. It was agreed that a syscall is
preferred for a variety or reasons. Here are just a few taken from
prior threads. Syscalls are safer than ioctl()s especially when
signaling to fds. Processes are a core kernel concept so a syscall
seems more appropriate. The layout of the syscall with its four
arguments would require the addition of a custom struct for the
ioctl() thereby causing at least the same amount or even more
complexity for userspace than a simple syscall. The new syscall will
replace multiple other pid-based syscalls (see description above).
The file-descriptors-for-processes concept introduced with this
syscall will be extended with other syscalls in the future. See also
[22], [23] and various other threads already linked in here.
Q-09: (Florian Weimer [24])
What happens if you use the new interface with an O_PATH descriptor?
A-09:
pidfds opened as O_PATH fds cannot be used to send signals to a
process (cf. [2]). Signaling processes through pidfds is the
equivalent of writing to a file. Thus, this is not an operation that
operates "purely at the file descriptor level" as required by the
open(2) manpage. See also [4].
/* References */
[1]: https://lore.kernel.org/lkml/20181029221037.87724-1-dancol@google.com/
[2]: https://lore.kernel.org/lkml/874lbtjvtd.fsf@oldenburg2.str.redhat.com/
[3]: https://lore.kernel.org/lkml/20181204132604.aspfupwjgjx6fhva@brauner.io/
[4]: https://lore.kernel.org/lkml/20181203180224.fkvw4kajtbvru2ku@brauner.io/
[5]: https://lore.kernel.org/lkml/20181121213946.GA10795@mail.hallyn.com/
[6]: https://lore.kernel.org/lkml/20181120103111.etlqp7zop34v6nv4@brauner.io/
[7]: https://lore.kernel.org/lkml/36323361-90BD-41AF-AB5B-EE0D7BA02C21@amacapital.net/
[8]: https://lore.kernel.org/lkml/87tvjxp8pc.fsf@xmission.com/
[9]: https://asciinema.org/a/IQjuCHew6bnq1cr78yuMv16cy
[11]: https://lore.kernel.org/lkml/F53D6D38-3521-4C20-9034-5AF447DF62FF@amacapital.net/
[12]: https://lore.kernel.org/lkml/87zhtjn8ck.fsf@xmission.com/
[13]: https://lore.kernel.org/lkml/871s6u9z6u.fsf@xmission.com/
[14]: https://lore.kernel.org/lkml/20181206231742.xxi4ghn24z4h2qki@brauner.io/
[15]: https://lore.kernel.org/lkml/20181207003124.GA11160@mail.hallyn.com/
[16]: https://lore.kernel.org/lkml/20181207015423.4miorx43l3qhppfz@brauner.io/
[17]: https://lore.kernel.org/lkml/CAGXu5jL8PciZAXvOvCeCU3wKUEB_dU-O3q0tDw4uB_ojMvDEew@mail.gmail.com/
[18]: https://lore.kernel.org/lkml/20181206222746.GB9224@mail.hallyn.com/
[19]: https://lore.kernel.org/lkml/20181208054059.19813-1-christian@brauner.io/
[20]: https://lore.kernel.org/lkml/8736rebl9s.fsf@oldenburg.str.redhat.com/
[21]: https://lore.kernel.org/lkml/20181228152012.dbf0508c2508138efc5f2bbe@linux-foundation.org/
[22]: https://lore.kernel.org/lkml/20181228233725.722tdfgijxcssg76@brauner.io/
[23]: https://lwn.net/Articles/773459/
[24]: https://lore.kernel.org/lkml/8736rebl9s.fsf@oldenburg.str.redhat.com/
[25]: https://lore.kernel.org/lkml/CAK8P3a0ej9NcJM8wXNPbcGUyOUZYX+VLoDFdbenW3s3114oQZw@mail.gmail.com/
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Jann Horn <jannh@google.com>
Cc: Andy Lutomirsky <luto@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Florian Weimer <fweimer@redhat.com>
Signed-off-by: Christian Brauner <christian@brauner.io>
Reviewed-by: Tycho Andersen <tycho@tycho.ws>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: David Howells <dhowells@redhat.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Serge Hallyn <serge@hallyn.com>
Acked-by: Aleksa Sarai <cyphar@cyphar.com>
(cherry picked from commit 3eb39f47934f9d5a3027fe00d906a45fe3a15fad)
Conflicts:
include/linux/proc_fs.h - trivial manual merge
include/uapi/asm-generic/unistd.h - trivial manual merge
kernel/signal.c
(1. manual merges because of 4.19 differences
2. change prepare_kill_siginfo() to use struct siginfo instead of
kernel_siginfo
3. change copy_siginfo_from_user_any() to use struct siginfo instead of
kernel_siginfo
4. change pidfd_send_signal() to use struct siginfo instead of
kernel_siginfo
5. use copy_from_user() instead of copy_siginfo_from_user() in
copy_siginfo_from_user_any())
Bug: 135608568
Test: test program using syscall(__NR_pidfd_send_signal,..) to send SIGKILL
Change-Id: I24e6298ecf036d1822f3fa6c5286984b4e195c16
Signed-off-by: Suren Baghdasaryan <surenb@google.com>
commit 98af37d624ed8c83f1953b1b6b2f6866011fc064 upstream.
In the fixes commit, removing SIGKILL from each thread signal mask and
executing "goto fatal" directly will skip the call to
"trace_signal_deliver". At this point, the delivery tracking of the
SIGKILL signal will be inaccurate.
Therefore, we need to add trace_signal_deliver before "goto fatal" after
executing sigdelset.
Note: SEND_SIG_NOINFO matches the fact that SIGKILL doesn't have any info.
Link: http://lkml.kernel.org/r/20190425025812.91424-1-weizhenliang@huawei.com
Fixes: cf43a757fd4944 ("signal: Restore the stop PTRACE_EVENT_EXIT")
Signed-off-by: Zhenliang Wei <weizhenliang@huawei.com>
Reviewed-by: Christian Brauner <christian@brauner.io>
Reviewed-by: Oleg Nesterov <oleg@redhat.com>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Ivan Delalande <colona@arista.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Deepa Dinamani <deepa.kernel@gmail.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit cf43a757fd49442bc38f76088b70c2299eed2c2f upstream.
In the middle of do_exit() there is there is a call
"ptrace_event(PTRACE_EVENT_EXIT, code);" That call places the process
in TACKED_TRACED aka "(TASK_WAKEKILL | __TASK_TRACED)" and waits for
for the debugger to release the task or SIGKILL to be delivered.
Skipping past dequeue_signal when we know a fatal signal has already
been delivered resulted in SIGKILL remaining pending and
TIF_SIGPENDING remaining set. This in turn caused the
scheduler to not sleep in PTACE_EVENT_EXIT as it figured
a fatal signal was pending. This also caused ptrace_freeze_traced
in ptrace_check_attach to fail because it left a per thread
SIGKILL pending which is what fatal_signal_pending tests for.
This difference in signal state caused strace to report
strace: Exit of unknown pid NNNNN ignored
Therefore update the signal handling state like dequeue_signal
would when removing a per thread SIGKILL, by removing SIGKILL
from the per thread signal mask and clearing TIF_SIGPENDING.
Acked-by: Oleg Nesterov <oleg@redhat.com>
Reported-by: Oleg Nesterov <oleg@redhat.com>
Reported-by: Ivan Delalande <colona@arista.com>
Cc: stable@vger.kernel.org
Fixes: 35634ffa1751 ("signal: Always notice exiting tasks")
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 7146db3317c67b517258cb5e1b08af387da0618b upstream.
Recently syzkaller was able to create unkillablle processes by
creating a timer that is delivered as a thread local signal on SIGHUP,
and receiving SIGHUP SA_NODEFERER. Ultimately causing a loop failing
to deliver SIGHUP but always trying.
When the stack overflows delivery of SIGHUP fails and force_sigsegv is
called. Unfortunately because SIGSEGV is numerically higher than
SIGHUP next_signal tries again to deliver a SIGHUP.
From a quality of implementation standpoint attempting to deliver the
timer SIGHUP signal is wrong. We should attempt to deliver the
synchronous SIGSEGV signal we just forced.
We can make that happening in a fairly straight forward manner by
instead of just looking at the signal number we also look at the
si_code. In particular for exceptions (aka synchronous signals) the
si_code is always greater than 0.
That still has the potential to pick up a number of asynchronous
signals as in a few cases the same si_codes that are used
for synchronous signals are also used for asynchronous signals,
and SI_KERNEL is also included in the list of possible si_codes.
Still the heuristic is much better and timer signals are definitely
excluded. Which is enough to prevent all known ways for someone
sending a process signals fast enough to cause unexpected and
arguably incorrect behavior.
Cc: stable@vger.kernel.org
Fixes: a27341cd5f ("Prioritize synchronous signals over 'normal' signals")
Tested-by: Dmitry Vyukov <dvyukov@google.com>
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 35634ffa1751b6efd8cf75010b509dcb0263e29b upstream.
Recently syzkaller was able to create unkillablle processes by
creating a timer that is delivered as a thread local signal on SIGHUP,
and receiving SIGHUP SA_NODEFERER. Ultimately causing a loop
failing to deliver SIGHUP but always trying.
Upon examination it turns out part of the problem is actually most of
the solution. Since 2.5 signal delivery has found all fatal signals,
marked the signal group for death, and queued SIGKILL in every threads
thread queue relying on signal->group_exit_code to preserve the
information of which was the actual fatal signal.
The conversion of all fatal signals to SIGKILL results in the
synchronous signal heuristic in next_signal kicking in and preferring
SIGHUP to SIGKILL. Which is especially problematic as all
fatal signals have already been transformed into SIGKILL.
Instead of dequeueing signals and depending upon SIGKILL to
be the first signal dequeued, first test if the signal group
has already been marked for death. This guarantees that
nothing in the signal queue can prevent a process that needs
to exit from exiting.
Cc: stable@vger.kernel.org
Tested-by: Dmitry Vyukov <dvyukov@google.com>
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Ref: ebf5ebe31d2c ("[PATCH] signal-fixes-2.5.59-A4")
History Tree: https://git.kernel.org/pub/scm/linux/kernel/git/tglx/history.git
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit a36700589b85443e28170be59fa11c8a104130a5 upstream.
While fixing an out of bounds array access in known_siginfo_layout
reported by the kernel test robot it became apparent that the same bug
exists in siginfo_layout and affects copy_siginfo_from_user32.
The straight forward fix that makes guards against making this mistake
in the future and should keep the code size small is to just take an
unsigned signal number instead of a signed signal number, as I did to
fix known_siginfo_layout.
Cc: stable@vger.kernel.org
Fixes: cc731525f2 ("signal: Remove kernel interal si_code magic")
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 3597dfe01d12f570bc739da67f857fd222a3ea66 ]
Instead of playing whack-a-mole and changing SEND_SIG_PRIV to
SEND_SIG_FORCED throughout the kernel to ensure a pid namespace init
gets signals sent by the kernel, stop allowing a pid namespace init to
ignore SIGKILL or SIGSTOP sent by the kernel. A pid namespace init is
only supposed to be able to ignore signals sent from itself and
children with SIG_DFL.
Fixes: 921cf9f630 ("signals: protect cinit from unblocked SIG_DFL signals")
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 22839869f21ab3850fbbac9b425ccc4c0023926f ]
The sigaltstack(2) system call fails with -ENOMEM if the new alternative
signal stack is found to be smaller than SIGMINSTKSZ. On architectures
such as arm64, where the native value for SIGMINSTKSZ is larger than
the compat value, this can result in an unexpected error being reported
to a compat task. See, for example:
https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=904385
This patch fixes the problem by extending do_sigaltstack to take the
minimum signal stack size as an additional parameter, allowing the
native and compat system call entry code to pass in their respective
values. COMPAT_SIGMINSTKSZ is just defined as SIGMINSTKSZ if it has not
been defined by the architecture.
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Dominik Brodowski <linux@dominikbrodowski.net>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Oleg Nesterov <oleg@redhat.com>
Reported-by: Steve McIntyre <steve.mcintyre@arm.com>
Tested-by: Steve McIntyre <93sam@debian.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Merge more updates from Andrew Morton:
- the rest of MM
- procfs updates
- various misc things
- more y2038 fixes
- get_maintainer updates
- lib/ updates
- checkpatch updates
- various epoll updates
- autofs updates
- hfsplus
- some reiserfs work
- fatfs updates
- signal.c cleanups
- ipc/ updates
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (166 commits)
ipc/util.c: update return value of ipc_getref from int to bool
ipc/util.c: further variable name cleanups
ipc: simplify ipc initialization
ipc: get rid of ids->tables_initialized hack
lib/rhashtable: guarantee initial hashtable allocation
lib/rhashtable: simplify bucket_table_alloc()
ipc: drop ipc_lock()
ipc/util.c: correct comment in ipc_obtain_object_check
ipc: rename ipcctl_pre_down_nolock()
ipc/util.c: use ipc_rcu_putref() for failues in ipc_addid()
ipc: reorganize initialization of kern_ipc_perm.seq
ipc: compute kern_ipc_perm.id under the ipc lock
init/Kconfig: remove EXPERT from CHECKPOINT_RESTORE
fs/sysv/inode.c: use ktime_get_real_seconds() for superblock stamp
adfs: use timespec64 for time conversion
kernel/sysctl.c: fix typos in comments
drivers/rapidio/devices/rio_mport_cdev.c: remove redundant pointer md
fork: don't copy inconsistent signal handler state to child
signal: make get_signal() return bool
signal: make sigkill_pending() return bool
...
make get_signal() already behaves like a boolean function. Let's actually
declare it as such too.
Link: http://lkml.kernel.org/r/20180602103653.18181-18-christian@brauner.io
Signed-off-by: Christian Brauner <christian@brauner.io>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: James Morris <james.morris@microsoft.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
sigkill_pending() already behaves like a boolean function. Let's actually
declare it as such too.
Link: http://lkml.kernel.org/r/20180602103653.18181-17-christian@brauner.io
Signed-off-by: Christian Brauner <christian@brauner.io>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: James Morris <james.morris@microsoft.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
legacy_queue() already behaves like a boolean function. Let's actually
declare it as such too.
Link: http://lkml.kernel.org/r/20180602103653.18181-16-christian@brauner.io
Signed-off-by: Christian Brauner <christian@brauner.io>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: James Morris <james.morris@microsoft.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
wants_signal() already behaves like a boolean function. Let's actually
declare it as such too.
Link: http://lkml.kernel.org/r/20180602103653.18181-15-christian@brauner.io
Signed-off-by: Christian Brauner <christian@brauner.io>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: James Morris <james.morris@microsoft.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The return value of flush_sigqueue_mask() is never checked anywhere.
Link: http://lkml.kernel.org/r/20180602103653.18181-14-christian@brauner.io
Signed-off-by: Christian Brauner <christian@brauner.io>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: James Morris <james.morris@microsoft.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
unhandled_signal() already behaves like a boolean function. Let's
actually declare it as such too. All callers treat it as such too.
Link: http://lkml.kernel.org/r/20180602103653.18181-13-christian@brauner.io
Signed-off-by: Christian Brauner <christian@brauner.io>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: James Morris <james.morris@microsoft.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
recalc_sigpending_tsk() already behaves like a boolean function. Let's
actually declare it as such too.
Link: http://lkml.kernel.org/r/20180602103653.18181-12-christian@brauner.io
Signed-off-by: Christian Brauner <christian@brauner.io>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: James Morris <james.morris@microsoft.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
has_pending_signals() already behaves like a boolean function. Let's
actually declare it as such too.
Link: http://lkml.kernel.org/r/20180602103653.18181-11-christian@brauner.io
Signed-off-by: Christian Brauner <christian@brauner.io>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: James Morris <james.morris@microsoft.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
sig_ignored() already behaves like a boolean function. Let's actually
declare it as such too.
Link: http://lkml.kernel.org/r/20180602103653.18181-10-christian@brauner.io
Signed-off-by: Christian Brauner <christian@brauner.io>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: James Morris <james.morris@microsoft.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
sig_task_ignored() already behaves like a boolean function. Let's
actually declare it as such too.
Link: http://lkml.kernel.org/r/20180602103653.18181-9-christian@brauner.io
Signed-off-by: Christian Brauner <christian@brauner.io>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: James Morris <james.morris@microsoft.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
sig_handler_ignored() already behaves like a boolean function. Let's
actually declare it as such too.
Link: http://lkml.kernel.org/r/20180602103653.18181-8-christian@brauner.io
Signed-off-by: Christian Brauner <christian@brauner.io>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: James Morris <james.morris@microsoft.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
kill_ok_by_cred() already behaves like a boolean function. Let's actually
declare it as such too.
Link: http://lkml.kernel.org/r/20180602103653.18181-7-christian@brauner.io
Signed-off-by: Christian Brauner <christian@brauner.io>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: James Morris <james.morris@microsoft.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The goto is not needed and does not add any clarity. Simply return
-EINVAL on unexpected sigset_t struct size directly.
Link: http://lkml.kernel.org/r/20180602103653.18181-6-christian@brauner.io
Signed-off-by: Christian Brauner <christian@brauner.io>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: James Morris <james.morris@microsoft.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
do_sigpending() returned 0 unconditionally so it doesn't make sense to
have it return at all. This allows us to simplify a bunch of syscall
callers.
Link: http://lkml.kernel.org/r/20180602103653.18181-5-christian@brauner.io
Signed-off-by: Christian Brauner <christian@brauner.io>
Acked-by: Al Viro <viro@zeniv.linux.org.uk>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: James Morris <james.morris@microsoft.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
may_ptrace_stop() already behaves like a boolean function. Let's actually
declare it as such too.
Link: http://lkml.kernel.org/r/20180602103653.18181-4-christian@brauner.io
Signed-off-by: Christian Brauner <christian@brauner.io>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: James Morris <james.morris@microsoft.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
kill_as_cred_perm() already behaves like a boolean function. Let's
actually declare it as such too.
Link: http://lkml.kernel.org/r/20180602103653.18181-3-christian@brauner.io
Signed-off-by: Christian Brauner <christian@brauner.io>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: James Morris <james.morris@microsoft.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Patch series "signal: refactor some functions", v3.
This series refactors a bunch of functions in signal.c to simplify parts
of the code.
The greatest single change is declaring the static do_sigpending() helper
as void which makes it possible to remove a bunch of unnecessary checks in
the syscalls later on.
This patch (of 17):
force_sigsegv() returned 0 unconditionally so it doesn't make sense to have
it return at all. In addition, there are no callers that check
force_sigsegv()'s return value.
Link: http://lkml.kernel.org/r/20180602103653.18181-2-christian@brauner.io
Signed-off-by: Christian Brauner <christian@brauner.io>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: James Morris <james.morris@microsoft.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Wen Yang <wen.yang99@zte.com.cn> and majiang <ma.jiang@zte.com.cn>
report that a periodic signal received during fork can cause fork to
continually restart preventing an application from making progress.
The code was being overly pessimistic. Fork needs to guarantee that a
signal sent to multiple processes is logically delivered before the
fork and just to the forking process or logically delivered after the
fork to both the forking process and it's newly spawned child. For
signals like periodic timers that are always delivered to a single
process fork can safely complete and let them appear to logically
delivered after the fork().
While examining this issue I also discovered that fork today will miss
signals delivered to multiple processes during the fork and handled by
another thread. Similarly the current code will also miss blocked
signals that are delivered to multiple process, as those signals will
not appear pending during fork.
Add a list of each thread that is currently forking, and keep on that
list a signal set that records all of the signals sent to multiple
processes. When fork completes initialize the new processes
shared_pending signal set with it. The calculate_sigpending function
will see those signals and set TIF_SIGPENDING causing the new task to
take the slow path to userspace to handle those signals. Making it
appear as if those signals were received immediately after the fork.
It is not possible to send real time signals to multiple processes and
exceptions don't go to multiple processes, which means that that are
no signals sent to multiple processes that require siginfo. This
means it is safe to not bother collecting siginfo on signals sent
during fork.
The sigaction of a child of fork is initially the same as the
sigaction of the parent process. So a signal the parent ignores the
child will also initially ignore. Therefore it is safe to ignore
signals sent to multiple processes and ignored by the forking process.
Signals sent to only a single process or only a single thread and delivered
during fork are treated as if they are received after the fork, and generally
not dealt with. They won't cause any problems.
V2: Added removal from the multiprocess list on failure.
V3: Use -ERESTARTNOINTR directly
V4: - Don't queue both SIGCONT and SIGSTOP
- Initialize signal_struct.multiprocess in init_task
- Move setting of shared_pending to before the new task
is visible to signals. This prevents signals from comming
in before shared_pending.signal is set to delayed.signal
and being lost.
V5: - rework list add and delete to account for idle threads
v6: - Use sigdelsetmask when removing stop signals
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=200447
Reported-by: Wen Yang <wen.yang99@zte.com.cn> and
Reported-by: majiang <ma.jiang@zte.com.cn>
Fixes: 4a2c7a7837 ("[PATCH] make fork() atomic wrt pgrp/session signals")
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
There are only two signals that are delivered to every member of a
signal group: SIGSTOP and SIGKILL. Signal delivery requires every
signal appear to be delivered either before or after a clone syscall.
SIGKILL terminates the clone so does not need to be considered. Which
leaves only SIGSTOP that needs to be considered when creating new
threads.
Today in the event of a group stop TIF_SIGPENDING will get set and the
fork will restart ensuring the fork syscall participates in the group
stop.
A fork (especially of a process with a lot of memory) is one of the
most expensive system so we really only want to restart a fork when
necessary.
It is easy so check to see if a SIGSTOP is ongoing and have the new
thread join it immediate after the clone completes. Making it appear
the clone completed happened just before the SIGSTOP.
The calculate_sigpending function will see the bits set in jobctl and
set TIF_SIGPENDING to ensure the new task takes the slow path to userspace.
V2: The call to task_join_group_stop was moved before the new task is
added to the thread group list. This should not matter as
sighand->siglock is held over both the addition of the threads,
the call to task_join_group_stop and do_signal_stop. But the change
is trivial and it is one less thing to worry about when reading
the code.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Add a function calculate_sigpending to test to see if any signals are
pending for a new task immediately following fork. Signals have to
happen either before or after fork. Today our practice is to push
all of the signals to before the fork, but that has the downside that
frequent or periodic signals can make fork take much much longer than
normal or prevent fork from completing entirely.
So we need move signals that we can after the fork to prevent that.
This updates the code to set TIF_SIGPENDING on a new task if there
are signals or other activities that have moved so that they appear
to happen after the fork.
As the code today restarts if it sees any such activity this won't
immediately have an effect, as there will be no reason for it
to set TIF_SIGPENDING immediately after the fork.
Adding calculate_sigpending means the code in fork can safely be
changed to not always restart if a signal is pending.
The new calculate_sigpending function sets sigpending if there
are pending bits in jobctl, pending signals, the freezer needs
to freeze the new task or the live kernel patching framework
need the new thread to take the slow path to userspace.
I have verified that setting TIF_SIGPENDING does make a new process
take the slow path to userspace before it executes it's first userspace
instruction.
I have looked at the callers of signal_wake_up and the code paths
setting TIF_SIGPENDING and I don't see anything else that needs to be
handled. The code probably doesn't need to set TIF_SIGPENDING for the
kernel live patching as it uses a separate thread flag as well. But
at this point it seems safer reuse the recalc_sigpending logic and get
the kernel live patching folks to sort out their story later.
V2: I have moved the test into schedule_tail where siglock can
be grabbed and recalc_sigpending can be reused directly.
Further as the last action of setting up a new task this
guarantees that TIF_SIGPENDING will be properly set in the
new process.
The helper calculate_sigpending takes the siglock and
uncontitionally sets TIF_SIGPENDING and let's recalc_sigpending
clear TIF_SIGPENDING if it is unnecessary. This allows reusing
the existing code and keeps maintenance of the conditions simple.
Oleg Nesterov <oleg@redhat.com> suggested the movement
and pointed out the need to take siglock if this code
was going to be called while the new task is discoverable.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
This is the bottom and by pushing this down it simplifies the callers
and otherwise leaves things as is. This is in preparation for allowing
fork to implement better handling of signals set to groups of processes.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
This information is already available in the callers and by pushing it
down it makes the code a little clearer, and allows implementing
better handling of signales set to a group of processes in fork.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
This information is already available in the callers and by pushing it
down it makes the code a little clearer, and allows better group
signal behavior in fork.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
This passes the information we already have at the call sight into
do_send_sig_info. Ultimately allowing for better handling of signals
sent to a group of processes during fork.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
This passes the information we already have at the call sight
into group_send_sig_info. Ultimatelly allowing for to better handle
signals sent to a group of processes.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Oleg Nesterov
Roman Gushchin
Greg Kroah-Hartman
Eric W. Biederman
Linus Torvalds
Joel Fernandes (Google)
Christian Brauner
Jann Horn
Zhenliang Wei
Will Deacon