There was commented out transfer_flags initialization.
And i think memset should fill entire structure, not only length of
pointer to it.
This makes the driver work properly now on my hardware.
Signed-off-by: Konstantin Katuev <kkatuev@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch fixes bug #13820 from bugzilla.kernel.org.
Quote: "If ETHTOOL_GLINK is not defined, the end for switch case is not
to be found."
Signed-off-by: Maximiliano David Bustos <md.bustos90@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Commit e31b82136d ("cfg80211/mac80211:
allow per-station GTKs") changed the signatures of these operations
but did not update the staging drivers.
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Remove unnecessary cast of firmware base address to integer before
adding an offset.
Fix direct use of sk_buff::network_header which is an offset rather
than a pointer on 64-bit architectures.
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Whenever the mac address of an batman interface is changed
check_known_mac_addr() is called to print a warning if the newly added
mac address exists an another batman interface. While looping through
the batman interface list check_known_mac_addr() only compares mac
addresses and does not make sure they belong to different interfaces,
thus always printing a warning.
Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>
Signed-off-by: Sven Eckelmann <sven.eckelmann@gmx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
55d1666b521cbed95924c8d4775fe272c103f08c incidentally disabled bonding
of packets first entering the mesh along with also disabling interface
alternating regardless of where the packet came from. This re-enables
these options.
Signed-off-by: Chris Lang <clang@gateworks.com>
Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>
Signed-off-by: Sven Eckelmann <sven.eckelmann@gmx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Unmap the rx buffer before mapping the new one in rtl8192_rx.
Failing to do so quickly exhausts the IOMMU memory during downloads:
[...] DMA: Out of SW-IOMMU space for 9100 bytes at device ...
Using "iommu=off mem=4g" also fixes the problem because
then pci_map_single does not allocate memory.
Tested on my personal laptop with a RTL8192E device. Without this
patch the kernel quickly runs out of IOMMU memory (downloading 5 MB
of data is sufficient to trigger it), with this patch applied
I haven't experienced any issues so far.
Signed-off-by: Daniel Lichtenberger <daniel.lichtenberger@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Identation says that copy_to_user() should be called only iff
wrq->u.essid.pointer is not zero. Also it is useless to call copy_to_user(0, ...).
Signed-off-by: Vasiliy Kulikov <segooon@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Add new USB ID for FT2870 for Belkin F6D4050 v1
Signed-off-by: Larry Finger <Larry.Finger@lwfinger.net>
Reported- and Tested-by: James Long <crogonint@yahoo.com>
Cc: Stable <stable@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Delete successive assignments to the same location. dhd_ops_virt contains
a subset of the definitions of dhd_ops_pri.
A simplified version of the semantic match that finds this problem is as
follows: (http://coccinelle.lip6.fr/)
// <smpl>
@@
expression i;
@@
*i = ...;
i = ...;
// </smpl>
Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Delete successive assignments to the same location. In three of the cases,
the two assignments are identical. In the case of the file
rt2860/common/cmm_aes.c, the assigned variable i is never used, so both
assignments are dropped.
A simplified version of the semantic match that finds this problem is as
follows: (http://coccinelle.lip6.fr/)
// <smpl>
@@
expression i;
@@
*i = ...;
i = ...;
// </smpl>
Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This fixes some places that dereference user pointers directly instead
of using get_user().
Please especially check my changes to IOCTL_BCM_GET_CURRENT_STATUS. The
original code modified the struct which "arg" was pointing to. I think
this was a bug in the original code and that we only wanted to write to
the OutputBuffer. Also with the original code you could read as much
memory as you wanted so I had to put a cap on OutputLength. The only
value of OutputLength that makes sense is sizeof(LINK_STATE) so now if
OutputLength is not sizeof(LINK_STATE) it returns -EINVAL.
Signed-off-by: Dan Carpenter <error27@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This silences all the sparse warnings in intel_sst_app_interface.c.
It was just a matter of adding __user annotations, I didn't find any
real bugs here. Quite a few of these were needed for stuff I added
earlier, sorry about that.
I removed a couple casts to (void *) that caused a warning like:
drivers/staging/intel_sst/intel_sst_app_interface.c:606:27:
warning: cast removes address space of expression
For example sst_drv_ctx->mailbox is already declared as
"void __iomem *mailbox" so casting it to void pointer isn't necessary
and it makes sparse complain because it removes the __user attribute.
Signed-off-by: Dan Carpenter <error27@gmail.com>
Cc: Vinod Koul <vinod.koul@intel.com>
Cc: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
There were some places in intel_sst_mmap_play_capture() that
dereferenced user pointers instead of copying the data to the kernel.
I removed the BUG_ON(!mmap_buf) and BUG_ON(!buf_entry) since those are
never possible in the current code.
Signed-off-by: Dan Carpenter <error27@gmail.com>
Cc: Vinod Koul <vinod.koul@intel.com>
Cc: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This is another patch about copying data to the kernel before using it.
SNDRV_SST_STREAM_DECODE is sort of tricky because we need to do a
copy_from_user() that gives us another two pointers and we have copy
those. Those again give us some more pointers that we have to copy.
Besides those problems, the code had a stack overflow:
- struct snd_sst_buff_entry ibuf_temp[param->ibufs->entries],
- obuf_temp[param->obufs->entries];
param->ibufs->entries comes from the user.
Signed-off-by: Dan Carpenter <error27@gmail.com>
Acked-by: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This is another patch about making a copy of the data into kernel space
before using it. It is easy to trigger a kernel oops in the original
code. If you passed a NULL to SNDRV_SST_SET_TARGET_DEVICE then it
called BUG_ON(). And SNDRV_SST_DRIVER_INFO would let you write the
information to arbitrary memory locations which is a security violation.
Signed-off-by: Dan Carpenter <error27@gmail.com>
Acked-by: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This code dereferences user supplied pointers directly instead of doing
a copy_from_user(). Some kernel configs put user and kernel memory in
different address spaces so this code isn't portable. Also the user
memory could be swapped out or in this case the pointer could just be
NULL leading to an oops.
Another thing is that it makes permission tests like this sort of
meaningless.
if (minor == STREAM_MODULE && rec_mute->stream_id == 0) {
retval = -EPERM;
break;
}
The user could set stream_id to 1 for the test and then change it later.
Signed-off-by: Dan Carpenter <error27@gmail.com>
Acked-by: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
configure_saa7146() didn't free irq on error.
saa_open() didn't decrease reference count of saa on error.
saa_ioctl() leaked information from the kernel stack to userland as it
didn't fill copied structs with zeros.
Signed-off-by: Vasiliy Kulikov <segooon@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Use effective UID instead of real UID for camera owner.
There is no need to check for pending signals just before successfull
return. Exit in case of pending signal also leaved camera in open state.
Signed-off-by: Vasiliy Kulikov <segooon@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
The tree has moved to "staging-2.6" not "staging-next-2.6" as all of the
staging development is now done in git, not just for the next tree.
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
ext4: Add new ext4 inode tracepoints
ext4: Don't call sb_issue_discard() in ext4_free_blocks()
ext4: do not try to grab the s_umount semaphore in ext4_quota_off
ext4: fix potential race when freeing ext4_io_page structures
ext4: handle writeback of inodes which are being freed
ext4: initialize the percpu counters before replaying the journal
ext4: "ret" may be used uninitialized in ext4_lazyinit_thread()
ext4: fix lazyinit hang after removing request
* git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty-2.6:
TTY: move .gitignore from drivers/char/ to drivers/tty/vt/
TTY: create drivers/tty/vt and move the vt code there
TTY: create drivers/tty and move the tty core files there
* 'staging-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging-next-2.6:
Staging: ath6kl: remove empty files that mess with 'distclean'
staging: ath6kl: Fixing the driver to use modified mmc_host structure
Staging: solo6x10: fix build problem
* 'sh-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/lethal/sh-2.6:
sh: clkfwk: Fix up checkpatch warnings.
sh: make some needlessly global sh7724 clocks static
sh: add clk_round_parent() to optimize parent clock rate
sh: Simplify phys_addr_mask()/PTE_PHYS_MASK for 29/32-bit.
sh: nommu: Support building without an uncached mapping.
sh: nommu: use 32-bit phys mode.
sh: mach-se: Fix up SE7206 no ioport build.
sh: intc: Update for single IRQ reservation helper.
sh: clkfwk: Fix up rate rounding error handling.
sh: mach-se: Rip out superfluous 7751 PIO routines.
sh: mach-se: Rip out superfluous 770x PIO routines.
sh: mach-edosk7705: Kill off machtype, consolidate board def.
sh: mach-edosk7705: update for this century, kill off PIO trapping.
sh: mach-se: Rip out superfluous 7206 PIO routines.
sh: mach-systemh: Kill off dead board.
sh: mach-snapgear: Kill off machtype, consolidate board def.
sh: mach-snapgear: Rip out superfluous PIO routines.
sh: mach-microdev: SuperIO-relative ioport mapping.
Commit 5c521830cf (ext4: Support discard requests when running in
no-journal mode) attempts to add sb_issue_discard() for data blocks
(in data=writeback mode) and in no-journal mode. Unfortunately, this
no longer works, because in commit dd3932eddf (block: remove
BLKDEV_IFL_WAIT), sb_issue_discard() only presents a synchronous
interface, and there are times when we call ext4_free_blocks() when we
are are holding a spinlock, or are otherwise in an atomic context.
For now, I've removed the call to sb_issue_discard() to prevent a
deadlock or (if spinlock debugging is enabled) failures like this:
BUG: scheduling while atomic: rc.sysinit/1376/0x00000002
Pid: 1376, comm: rc.sysinit Not tainted 2.6.36-ARCH #1
Call Trace:
[<ffffffff810397ce>] __schedule_bug+0x5e/0x70
[<ffffffff81403110>] schedule+0x950/0xa70
[<ffffffff81060bad>] ? insert_work+0x7d/0x90
[<ffffffff81060fbd>] ? queue_work_on+0x1d/0x30
[<ffffffff81061127>] ? queue_work+0x37/0x60
[<ffffffff8140377d>] schedule_timeout+0x21d/0x360
[<ffffffff812031c3>] ? generic_make_request+0x2c3/0x540
[<ffffffff81402680>] wait_for_common+0xc0/0x150
[<ffffffff81041490>] ? default_wake_function+0x0/0x10
[<ffffffff812034bc>] ? submit_bio+0x7c/0x100
[<ffffffff810680a0>] ? wake_bit_function+0x0/0x40
[<ffffffff814027b8>] wait_for_completion+0x18/0x20
[<ffffffff8120a969>] blkdev_issue_discard+0x1b9/0x210
[<ffffffff811ba03e>] ext4_free_blocks+0x68e/0xb60
[<ffffffff811b1650>] ? __ext4_handle_dirty_metadata+0x110/0x120
[<ffffffff811b098c>] ext4_ext_truncate+0x8cc/0xa70
[<ffffffff810d713e>] ? pagevec_lookup+0x1e/0x30
[<ffffffff81191618>] ext4_truncate+0x178/0x5d0
[<ffffffff810eacbb>] ? unmap_mapping_range+0xab/0x280
[<ffffffff810d8976>] vmtruncate+0x56/0x70
[<ffffffff811925cb>] ext4_setattr+0x14b/0x460
[<ffffffff811319e4>] notify_change+0x194/0x380
[<ffffffff81117f80>] do_truncate+0x60/0x90
[<ffffffff811e08fa>] ? security_inode_permission+0x1a/0x20
[<ffffffff811eaec1>] ? tomoyo_path_truncate+0x11/0x20
[<ffffffff81127539>] do_last+0x5d9/0x770
[<ffffffff811278bd>] do_filp_open+0x1ed/0x680
[<ffffffff8140644f>] ? page_fault+0x1f/0x30
[<ffffffff81132bfc>] ? alloc_fd+0xec/0x140
[<ffffffff81118db1>] do_sys_open+0x61/0x120
[<ffffffff81118e8b>] sys_open+0x1b/0x20
[<ffffffff81002e6b>] system_call_fastpath+0x16/0x1b
https://bugzilla.kernel.org/show_bug.cgi?id=22302
Reported-by: Mathias Burén <mathias.buren@gmail.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: jiayingz@google.com
It's not needed to sync the filesystem, and it fixes a lock_dep complaint.
Signed-off-by: Dmitry Monakhov <dmonakhov@gmail.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Reviewed-by: Jan Kara <jack@suse.cz>
Use an atomic_t and make sure we don't free the structure while we
might still be submitting I/O for that page.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
The following BUG can occur when an inode which is getting freed when
it still has dirty pages outstanding, and it gets deleted (in this
because it was the target of a rename). In ordered mode, we need to
make sure the data pages are written just in case we crash before the
rename (or unlink) is committed. If the inode is being freed then
when we try to igrab the inode, we end up tripping the BUG_ON at
fs/ext4/page-io.c:146.
To solve this problem, we need to keep track of the number of io
callbacks which are pending, and avoid destroying the inode until they
have all been completed. That way we don't have to bump the inode
count to keep the inode from being destroyed; an approach which
doesn't work because the count could have already been dropped down to
zero before the inode writeback has started (at which point we're not
allowed to bump the count back up to 1, since it's already started
getting freed).
Thanks to Dave Chinner for suggesting this approach, which is also
used by XFS.
kernel BUG at /scratch_space/linux-2.6/fs/ext4/page-io.c:146!
Call Trace:
[<ffffffff811075b1>] ext4_bio_write_page+0x172/0x307
[<ffffffff811033a7>] mpage_da_submit_io+0x2f9/0x37b
[<ffffffff811068d7>] mpage_da_map_and_submit+0x2cc/0x2e2
[<ffffffff811069b3>] mpage_add_bh_to_extent+0xc6/0xd5
[<ffffffff81106c66>] write_cache_pages_da+0x2a4/0x3ac
[<ffffffff81107044>] ext4_da_writepages+0x2d6/0x44d
[<ffffffff81087910>] do_writepages+0x1c/0x25
[<ffffffff810810a4>] __filemap_fdatawrite_range+0x4b/0x4d
[<ffffffff810815f5>] filemap_fdatawrite_range+0xe/0x10
[<ffffffff81122a2e>] jbd2_journal_begin_ordered_truncate+0x7b/0xa2
[<ffffffff8110615d>] ext4_evict_inode+0x57/0x24c
[<ffffffff810c14a3>] evict+0x22/0x92
[<ffffffff810c1a3d>] iput+0x212/0x249
[<ffffffff810bdf16>] dentry_iput+0xa1/0xb9
[<ffffffff810bdf6b>] d_kill+0x3d/0x5d
[<ffffffff810be613>] dput+0x13a/0x147
[<ffffffff810b990d>] sys_renameat+0x1b5/0x258
[<ffffffff81145f71>] ? _atomic_dec_and_lock+0x2d/0x4c
[<ffffffff810b2950>] ? cp_new_stat+0xde/0xea
[<ffffffff810b29c1>] ? sys_newlstat+0x2d/0x38
[<ffffffff810b99c6>] sys_rename+0x16/0x18
[<ffffffff81002a2b>] system_call_fastpath+0x16/0x1b
Reported-by: Nick Bowler <nbowler@elliptictech.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Tested-by: Nick Bowler <nbowler@elliptictech.com>
These clocks are currently only used inside one .c file and are not
declared in any headers, therefore having them global is useless.
Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Sometimes it is possible and reasonable to adjust the parent clock rate to
improve precision of the child clock, e.g., if the child clock has no siblings.
clk_round_parent() is a new addition to the SH clock-framework API, that
implements such an optimization for child clocks with divisors, taking all
integer values in a range.
Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
These two .h files would get removed from the tree when doing
make distclean
It turns out they are not needed at all, so just delete them which fixes
people's git trees when doing development.
Reported-by: Andi Kleen <andi@firstfloor.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
While scanning the floopy code due to c093ee4f07 ("floppy: fix
use-after-free in module load failure path"), I found one more instance
of trying to access disk->queue pointer after doing put_disk() on
gendisk. For some reason , floppy moule still loads/unloads fine. The
object is probably still around with right pointer values.
o There seems to be one more instance of trying to cleanup the request
queue after we have called put_disk() on associated gendisk.
o This fix is more out of code inspection. Even without this fix for
some reason I am able to load/unload floppy module without any
issues.
o Floppy module loads/unloads fine after the fix.
Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The autogenerated files (consolemap_deftbl.c and defkeymap.c) need to
be ignored by git, so move the .gitignore file that was doing it to the
properly location now that the files have moved as well.
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Commit 27ae60f8f7 ("ipw2x00: replace "ieee80211" with "libipw" where
appropriate") changed DRV_NAME to be "libipw", but didn't properly fix
up the places where it was used to specify the name for the /proc/net/
directory.
For backwards compatibility reasons, that directory name remained
"ieee80211", but due to the DRV_NAME change, the error case printouts
and the cleanup functions now used "libipw" instead. Which made it all
fail badly.
For example, on module unload as reported by Randy:
WARNING: at fs/proc/generic.c:816 remove_proc_entry+0x156/0x35e()
name 'libipw'
because it's trying to unregister a /proc directory that obviously
doesn't even exist.
Clean it all up to use DRV_PROCNAME for the actual /proc directory name.
Reported-and-tested-by: Randy Dunlap <randy.dunlap@oracle.com>
Cc: Pavel Roskin <proski@gnu.org>
Cc: John W. Linville <linville@tuxdriver.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* 'kvm-updates/2.6.37' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
KVM: PPC: BookE: Load the lower half of MSR
KVM: PPC: BookE: fix sleep with interrupts disabled
KVM: PPC: e500: Call kvm_vcpu_uninit() before kvmppc_e500_tlb_uninit().
PPC: KVM: Book E doesn't have __end_interrupts.
KVM: x86: Issue smp_call_function_many with preemption disabled
KVM: x86: fix information leak to userland
KVM: PPC: fix information leak to userland
KVM: MMU: fix rmap_remove on non present sptes
KVM: Write protect memory after slot swap
Commit 488211844e ("floppy: switch to one queue per drive instead of
sharing a queue") introduced a use-after-free. We do "put_disk()" on
the disk device _before_ we then clean up the queue associated with that
disk.
Move the put_disk() down to avoid dereferencing a free'd data structure.
Cc: Jens Axboe <jaxboe@fusionio.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Reported-and-tested-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Commit d9ca07a05c ("watchdog: Avoid kernel crash when disabling
watchdog") introduces a section mismatch.
Now that we reference no_watchdog from non-__init code it can no longer
be __initdata.
Signed-off-by: David Daney <ddaney@caviumnetworks.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6: (41 commits)
inet_diag: Make sure we actually run the same bytecode we audited.
netlink: Make nlmsg_find_attr take a const nlmsghdr*.
fib: fib_result_assign() should not change fib refcounts
netfilter: ip6_tables: fix information leak to userspace
cls_cgroup: Fix crash on module unload
memory corruption in X.25 facilities parsing
net dst: fix percpu_counter list corruption and poison overwritten
rds: Remove kfreed tcp conn from list
rds: Lost locking in loop connection freeing
de2104x: fix panic on load
atl1 : fix panic on load
netxen: remove unused firmware exports
caif: Remove noisy printout when disconnecting caif socket
caif: SPI-driver bugfix - incorrect padding.
caif: Bugfix for socket priority, bindtodev and dbg channel.
smsc911x: Set Ethernet EEPROM size to supported device's size
ipv4: netfilter: ip_tables: fix information leak to userland
ipv4: netfilter: arp_tables: fix information leak to userland
cxgb4vf: remove call to stop TX queues at load time.
cxgb4: remove call to stop TX queues at load time.
...
* 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/ieee1394/linux1394-2.6:
firewire: ohci: fix race when reading count in AR descriptor
firewire: ohci: avoid reallocation of AR buffers
firewire: ohci: fix race in AR split packet handling
firewire: ohci: fix buffer overflow in AR split packet handling
* git://git.kernel.org/pub/scm/linux/kernel/git/sfrench/cifs-2.6:
cifs: make cifs_set_oplock_level() take a cifsInodeInfo pointer
cifs: dereferencing first then checking
cifs: trivial comment fix: tlink_tree is now a rbtree
[CIFS] Cleanup unused variable build warning
cifs: convert tlink_tree to a rbtree
cifs: store pointer to master tlink in superblock (try #2)
cifs: trivial doc fix: note setlease implemented
CIFS: Add cifs_set_oplock_level
FS: cifs, remove unneeded NULL tests
posix-cpu-timers.c correctly assumes that the dying process does
posix_cpu_timers_exit_group() and removes all !CPUCLOCK_PERTHREAD
timers from signal->cpu_timers list.
But, it also assumes that timer->it.cpu.task is always the group
leader, and thus the dead ->task means the dead thread group.
This is obviously not true after de_thread() changes the leader.
After that almost every posix_cpu_timer_ method has problems.
It is not simple to fix this bug correctly. First of all, I think
that timer->it.cpu should use struct pid instead of task_struct.
Also, the locking should be reworked completely. In particular,
tasklist_lock should not be used at all. This all needs a lot of
nontrivial and hard-to-test changes.
Change __exit_signal() to do posix_cpu_timers_exit_group() when
the old leader dies during exec. This is not the fix, just the
temporary hack to hide the problem for 2.6.37 and stable. IOW,
this is obviously wrong but this is what we currently have anyway:
cpu timers do not work after mt exec.
In theory this change adds another race. The exiting leader can
detach the timers which were attached to the new leader. However,
the window between de_thread() and release_task() is small, we
can pretend that sys_timer_create() was called before de_thread().
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>