Commit graph

143694 commits

Author SHA1 Message Date
Hendrik Brueckner
3fa6b5adbe af_iucv: Fix race when queuing incoming iucv messages
AF_IUCV runs into a race when queuing incoming iucv messages
and receiving the resulting backlog.

If the Linux system is under pressure (high load or steal time),
the message queue grows up, but messages are not received and queued
onto the backlog queue. In that case, applications do not
receive any data with recvmsg() even if AF_IUCV puts incoming
messages onto the message queue.

The race can be avoided if the message queue spinlock in the
message_pending callback is spreaded across the entire callback
function.

Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Ursula Braun <ursula.braun@de.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-04-21 23:43:15 -07:00
Hendrik Brueckner
e14ad5fa87 af_iucv: Test additional sk states in iucv_sock_shutdown
Add few more sk states in iucv_sock_shutdown().

Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Ursula Braun <ursula.braun@de.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-04-21 23:43:15 -07:00
Hendrik Brueckner
fe86e54ef9 af_iucv: Reject incoming msgs if RECV_SHUTDOWN is set
Reject incoming iucv messages if the receive direction has been shut down.
It avoids that the queue of outstanding messages increases and exceeds the
message limit of the iucv communication path.

Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Ursula Braun <ursula.braun@de.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-04-21 23:43:14 -07:00
Hendrik Brueckner
60d3705fcb af_iucv: fix oops in iucv_sock_recvmsg() for MSG_PEEK flag
If iucv_sock_recvmsg() is called with MSG_PEEK flag set, the skb is enqueued
twice. If the socket is then closed, the pointer to the skb is freed twice.

Remove the skb_queue_head() call for MSG_PEEK, because the skb_recv_datagram()
function already handles MSG_PEEK (does not dequeue the skb).

Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Ursula Braun <ursula.braun@de.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-04-21 23:43:13 -07:00
Ursula Braun
bbe188c8f1 af_iucv: consider state IUCV_CLOSING when closing a socket
Make sure a second invocation of iucv_sock_close() guarantees proper
freeing of an iucv path.

Signed-off-by: Ursula Braun <ursula.braun@de.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-04-21 23:43:13 -07:00
Alexander Beregalov
bf98a82633 sa1100_ir: fix build breakage
Fix simple typo. Caused by commit
a1de966682
("irda/sa1100_ir: convert to net_device_ops").

Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Alexander Beregalov <a.beregalov@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-04-21 18:12:11 -07:00
Reinette Chatre
df833b1d73 iwlwifi: DMA fixes
A few issues wrt DMA were uncovered when using the driver with swiotlb.
- driver should not use memory after it has been mapped
- iwl3945's RX queue management cannot use all of iwlagn because
  the size of the RX buffer is different. Revert back to using
  iwl3945 specific routines that map/unmap memory.
- no need to "dma_syn_single_range_for_cpu" followed by pci_unmap_single,
  we can just call pci_unmap_single initially
- only map the memory area that will be used by device. this is especially
  relevant to the mapping of iwl_cmd. we should not map the entire
  structure because the meta data at the beginning of structure contains
  the address to be used later for unmapping. If the address to be used for
  unmapping is stored in mapped data it creates a problem.
- ensure that _if_ memory needs to be modified after it is mapped that we
  call _sync_single_for_cpu first, and then release it back to device with
  _sync_single_for_device
- we mapped the wrong length of data for host commands, with mapped length
  differing with length provided to device, fix that.

Thanks to Jason Andryuk <jandryuk@gmail.com> for significant bisecting
help to find these issues.

This fixes http://www.intellinuxwireless.org/bugzilla/show_bug.cgi?id=1964

Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
Tested-by: Jason Andryuk <jandryuk@gmail.com>
Tested-by: Ben Gamari <bgamari@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2009-04-21 16:43:34 -04:00
Reinette Chatre
d2ee9cd2e2 iwlwifi: add debugging for TX path
When debugging TX issues it is helpful to know the seq nr of the
frame being transmitted. The seq nr is printed as part of ucode's
log informing us which frame is being processed. Having this information
printed in driver log makes it easy to match activities between driver
and firmware.

Also make possible to print TX flags directly. These are already printed
as part of entire TX command, but having it printed directly in cpu format
makes it easier to look at.

Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2009-04-21 16:43:34 -04:00
Rami Rosen
c491bf1205 mwl8: fix build warning.
This patch fixes a build warning in mwl8.c.
(Marvell TOPDOG wireless driver)

The warning it fixes is: "large integer implicitly truncated to unsigned type."

The rx_ctrl member of the mwl8k_rx_desc struct is 8 bit (__u8 ), whereas trying
to assign it a 32 bit value (which is returned from  cpu_to_le32())
causes the compiler to issue
a truncation warning.

Signed-off-by: Rami Rosen <ramirose@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2009-04-21 16:43:33 -04:00
Johannes Berg
d1bcb9f127 mac80211: fix alignment calculation bug
When checking whether or not a given frame needs to be
moved to be properly aligned to a 4-byte boundary, we
use & 4 which wasn't intended, this code should check
the lowest two bits.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2009-04-21 16:43:33 -04:00
Reinette Chatre
7d42081a27 mac80211: do not print WARN if config interface
It is expected that config interface will always succeed as mac80211
will only request what driver supports. The exception here is when a
device has rfkill enabled. At this time the rfkill state is unknown to
mac80211 and config interface can fail. When this happens we deal with
this error instead of printing a WARN.

Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2009-04-21 16:43:32 -04:00
Reinette Chatre
71d449b55a iwl3945: use cancel_delayed_work_sync to cancel rfkill_poll
Users reported lockup with work still trying to run
after module has been unloaded.

http://thread.gmane.org/gmane.linux.kernel.wireless.general/30594/focus=30601

Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
Reported-by: TJ <ubuntu@tjworld.net>
Reported-by: Huaxu Wan <huaxu.wan@linux.intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2009-04-21 16:43:32 -04:00
Jay Sternberg
4b6f764e14 iwlwifi: fix EEPROM validation mask to include OTP only devices
Fix the bug where some revisions of 6000 series hardware cannot
be used. Later versions of 6000 series have the EEPROM replaced by
OTP. For these devices to be used we need to expand valid EEPROM mask.

Signed-off-by: Jay Sternberg <jay.e.sternberg@linux.intel.com>
Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2009-04-21 16:43:30 -04:00
Michael S. Tsirkin
6f26c9a755 tun: fix tun_chr_aio_write so that aio works
aio_write gets const struct iovec * but tun_chr_aio_write casts this to struct
iovec * and modifies the iovec. As a result, attempts to use io_submit
to send packets to a tun device fail with weird errors such as EINVAL.

Since tun is the only user of skb_copy_datagram_from_iovec, we can
fix this simply by changing the later so that it does not
touch the iovec passed to it.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-04-21 05:42:46 -07:00
Michael S. Tsirkin
43b39dcdbd tun: fix tun_chr_aio_read so that aio works
aio_read gets const struct iovec * but tun_chr_aio_read casts this to struct
iovec * and modifies the iovec. As a result, attempts to use io_submit
to get packets from a tun device fail with weird errors such as EINVAL.

Fix by using the new skb_copy_datagram_const_iovec.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-04-21 05:42:45 -07:00
Michael S. Tsirkin
0a1ec07a67 net: skb_copy_datagram_const_iovec()
There's an skb_copy_datagram_iovec() to copy out of a paged skb,
but it modifies the iovec, and does not support starting
at an offset in the destination. We want both in tun.c, so let's
add the function.

It's a carbon copy of skb_copy_datagram_iovec() with enough changes to
be annoying.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-04-21 05:42:44 -07:00
Johannes Berg
1bb593801e atmel: fix netdev ops conversion
sparse says:

drivers/net/wireless/atmel.c:1501:3: warning: Initializer entry defined twice
drivers/net/wireless/atmel.c:1505:3:   also defined here

and it's correct; atmel has its own ndo_change_mtu and
shouldn't use eth_change_mtu.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-04-21 02:08:51 -07:00
Joakim Tjernlund
0cededf3ff ucc_geth: Move freeing of TX packets to NAPI context
This will make the system alot more responsive while ping flooding the
ucc_geth ethernet interface.

Also set NAPI weight to 64 as this is a common value.

Signed-off-by: Joakim Tjernlund <Joakim.Tjernlund@transmode.se>
Signed-off-by: Anton Vorontsov <avorontsov@ru.mvista.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-04-21 02:07:17 -07:00
Ken Kawasaki
99b28c4709 pcnet_cs: add cis(firmware) of the Allied Telesis LA-PCM
pcnet_cs: add cis(firmware) of the Allied Telesis LA-PCM

Signed-off-by: Ken Kawasaki <ken_kawasaki@spring.nifty.jp>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-04-21 02:06:14 -07:00
Jianjun Kong
d035fbccc4 rtl8139: unify the struct's name
unify the struct's name of "struct rtl8139_private *np" to "struct rtl8139_private *tp"

most of them like this:
struct rtl8139_private *tp = netdev_priv(dev);

Signed-off-by: Amos Kong <jianjun@zeuux.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-04-21 02:02:53 -07:00
Patrick McHardy
b1b67dd45a net: factor out ethtool invocation of vlan/macvlan drivers
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-04-21 02:00:51 -07:00
Peter Holik
4510d7cb8b usb driver for intellon int51x1 based PLC like devolo dlan duo
usb driver for intellon int51x1 based PLC like devolo dlan duo
with improvements suggested by the guys of the mailinglist:
- name and prefix with int51x1 (Florian Fainelli)
- use conversion functions cpu_to_le16 / le16_to_cpu (Oliver Neukum)
- use pskb_may_pull instead of skb->len (Ilpo Järvinen)
- better code in tx_fixup (Ilpo Järvinen)
- use gotos for error handling (Ilpo Järvinen)
- better description (Jon Smirl)

Signed-off-by: Peter Holik <peter@holik.at>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-04-21 01:55:59 -07:00
Peter Holik
03ad032bb7 export usbnet_get_ethernet_addr from usbnet and fixed cdc_ether.c
because of using the same function get_ethernet_addr as cdc_ether.c
i export usbnet_get_ethernet_addr from usbnet and fixed cdc_ether
(suggested by Oliver Neukum).

Signed-off-by: Peter Holik <peter@holik.at>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-04-21 01:55:59 -07:00
Roland Dreier
1a44cc3778 mlx4_en: Fix cleanup if workqueue create in mlx4_en_add() fails
If creating a workqueue fails, don't jump to the error path where that
same workqueue is destroyed, since destroy_workqueue() can't handle a
NULL pointer.

This was spotted by the Coverity checker (CID 2617).

Signed-off-by: Roland Dreier <rolandd@cisco.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-04-21 01:47:08 -07:00
Yevgeny Petrilin
b1b243afac mlx4_en: Move to SW counters for total bytes and packets
The per ring counters are implemented in SW. Now moving to have the total
counters as the sum of all rings. This way the numbers will always be consistent
and we no longer depend on HW buffer size limitations for those counters
that can be insufficient in some cases.

Signed-off-by: Yevgeny Petrilin <yevgenyp@mellanox.co.il>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-04-21 01:47:07 -07:00
Yevgeny Petrilin
45b4d66d69 mlx4_en: use NETIF_F_IP_CSUM | NETIF_F_IPV6_CSUM for tx csum at initialization
The former usage was to set the NETIF_F_HW_CSUM flag which is not used
in get_tx_csum. It caused Ethtool to show tx checksum as "on" even
though it was turned off in previous operation.

Signed-off-by: Yevgeny Petrilin <yevgenyp@mellanox.co.il>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-04-21 01:47:07 -07:00
Yevgeny Petrilin
966508f7a5 mlx4_en: Assign dummy event handler for TX queue
The low level driver always assumes this handler exists.
The lack of it could cause kernel panic

Signed-off-by: Yevgeny Petrilin <yevgenyp@mellanox.co.il>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-04-21 01:47:05 -07:00
Yevgeny Petrilin
1e338db56e mlx4_en: Fix a race at restart task
The query whether the port is up or not should be done at
the execution of the restart task and not when it is queued.

Signed-off-by: Yevgeny Petrilin <yevgenyp@mellanox.co.il>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-04-21 01:47:04 -07:00
Yevgeny Petrilin
9a4f92a603 mlx4_en: Fix error handling while activating RX rings
In case of failure of either srq creation or page allocation,
the cleanup code handled the failed ring as well, and tried
to destroy resources that where not allocated.

Signed-off-by: Yevgeny Petrilin <yevgenyp@mellanox.co.il>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-04-21 01:47:03 -07:00
Matt Carlson
bb9e63e271 tg3: Update version to 3.99
This patch updates the tg3 version to 3.99.

Signed-off-by: Matt Carlson <mcarlson@broadcom.com>
Signed-off-by: Michael Chan <mchan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-04-21 01:41:03 -07:00
Matt Carlson
daba2a631d tg3: Restore LAA sooner in shutdown sequence
After a shutdown reset, the LAA needs to be restored before posting the
post-reset signature in shared memory.  If the LAA is not restored
before then, the bootcode will assume the factory default MAC address
and WOL will not work with the LAA.

Signed-off-by: Matt Carlson <mcarlson@broadcom.com>
Signed-off-by: Michael Chan <mchan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-04-21 01:41:03 -07:00
Matt Carlson
9cf74ebb63 tg3: Limit CLKREQ fix to A[01] of 57780 asic rev
This patch restricts the CLKREQ bugfix to the A0 and A1 revisions
of 57780 ASIC rev chips.

Signed-off-by: Matt Carlson <mcarlson@broadcom.com>
Signed-off-by: Michael Chan <mchan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-04-21 01:41:02 -07:00
Matt Carlson
8d519ab286 tg3: Allow 5761 WOL and LED fixes to 5761S too
The 5761 WOL and LED fixes used the PCI device ID to as the activation
key.  The 5761S requires the same process.

Signed-off-by: Matt Carlson <mcarlson@broadcom.com>
Signed-off-by: Michael Chan <mchan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-04-21 01:41:02 -07:00
Matt Carlson
33466d938f tg3: Prevent send BD corruption
On rare occasions, send BD corruptions can occur.  This patch
fixes the problem by increasing the L1 entry threshold to 4
milliseconds.

Signed-off-by: Matt Carlson <mcarlson@broadcom.com>
Signed-off-by: Michael Chan <mchan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-04-21 01:41:01 -07:00
Matt Carlson
df259d8cba tg3: Handle NVRAM absent cases
Some 57780 ASIC revision parts do not have NVRAM.  Code the driver so
that it is tolerant of this configuration.

Signed-off-by: Matt Carlson <mcarlson@broadcom.com>
Signed-off-by: Michael Chan <mchan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-04-21 01:41:00 -07:00
Matt Carlson
624f8e5082 tg3: Allow screaming interrupt detection
The tg3 driver's ISR is coded to accept interrupts as its own if the
status block tag does not equal the last tag the driver has seen.  The
last_tag field is updated from tg3_poll.  In a screaming interrupt
situation from another device sharing tg3's IRQ, tg3_poll does not get
a chance to be called, so the last_tag will always be out of sync with
the status block tag.  Consequently, the driver will continually
declare the screaming interrupts as its own, thus thwarting the
screaming interrupt detection logic.

This patch solves the problem by creating a new last_irq_tag member and
recording the status block tag in the ISR.  The ISR then checks the
last_irq_tag for interrupt ownership.

Many thanks to John Marvin for the detailed bug report and analysis and
Michael Chan for the bugfix.

Signed-off-by: Matt Carlson <mcarlson@broadcom.com>
Signed-off-by: Michael Chan <mchan@broadcom.com>
Tested-by: John Marvin <jsm@fc.hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-04-21 01:41:00 -07:00
David S. Miller
e5e9743bb7 Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6
Conflicts:
	net/core/dev.c
2009-04-21 01:32:26 -07:00
David S. Miller
775d8d9315 Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/linville/wireless-2.6 2009-04-20 15:33:46 -07:00
Matt Carlson
62cedd11f6 tg3: Fix SEEPROM accesses
The recent NVRAM patches sanitized how the driver deals with NVRAM
data, but they failed to bring the SEEPROM interfaces inline with
the new strategy.  This patch brings the SEEPROM interfaces up to date.
This patch also reverts commit 0d489ffb76
("tg3: fix big endian MAC address collection failure").

Signed-off-by: Matt Carlson <mcarlson@broadcom.com>
Signed-off-by: Michael Chan <mchan@broadcom.com>
Tested-by: Robin Holt <holt@sgi.com>
Tested-by: James Bottomley <james.bottomley@HansenPartnership.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-04-20 14:52:29 -07:00
Johannes Berg
7e0986c17f mac80211: fix basic rate bitmap calculation
"mac80211: fix basic rates setting from association response"
introduced a copy/paste error.

Unfortunately, this not just leads to wrong data being passed
to the driver but is remotely exploitable for some hardware or
driver combinations.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Cc: stable@kernel.org [2.6.29]
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2009-04-20 16:36:26 -04:00
Kalle Valo
ad935687db mac80211: fix beacon loss detection after scan
Currently beacon loss detection triggers after a scan. A probe request
is sent and a message like this is printed to the log:

wlan0: beacon loss from AP 00:12:17:e7:98:de - sending probe request

But in fact there is no beacon loss, the beacons are just not received
because of the ongoing scan. Fix it by updating last_beacon after
the scan has finished.

Reported-by: Jaswinder Singh Rajput <jaswinder@kernel.org>
Signed-off-by: Kalle Valo <kalle.valo@iki.fi>
Acked-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2009-04-20 16:36:26 -04:00
Jouni Malinen
d91c01c757 nl80211: Make nl80211_send_mlme_event() atomic
One of the code paths sending deauth/disassoc events ends up calling
this function with rcu_read_lock held, so we must use GFP_ATOMIC in
allocation routines.

Reported-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: Jouni Malinen <j@w1.fi>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2009-04-20 16:36:26 -04:00
Christian Lamparter
e10a9dfc35 ar9170usb: fix hang on resume
This patch fixes a hang on resume when the filesystem is not
available and request_firmware blocks.

However, the device does not accept the firmware on resume.
and it will exit with:

> firmware part 1 upload failed (-71).
> device is in a bad state. please reconnect it!

Reported-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: Christian Lamparter <chunkeey@web.de>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2009-04-20 16:36:26 -04:00
Robert P. J. Day
18aaab15f9 MAC80211: Remove unused MAC80211_VERBOSE_SPECT_MGMT_DEBUG.
Remove this unused Kconfig variable, which Intel apparently once
promised to make use of but never did.

Signed-off-by: Robert P. J. Day <rpjday@crashcourse.ca>
Acked-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2009-04-20 16:36:26 -04:00
Joerg Albert
230f7af0d8 mwl8k: fix module re-insertion bug
swap mwl8k_remove and mwl8k_shutdown functions to allow
"rmmod mwl8k; modprobe mwl8k"

Signed-off-by: Joerg Albert <jal2@gmx.de>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2009-04-20 16:36:26 -04:00
Christian Lamparter
c3b93c878d p54: deactivate broken powersave function
This patch deactivates powersave in station mode.

It does not work correctly yet, so the code does more harm than good.

Reported-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: Christian Lamparter <chunkeey@web.de>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2009-04-20 16:36:26 -04:00
Joe Perches
125143966f iwl3945-base.c: Add missing space to debug print
"not" is not printed without a space after %pM

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2009-04-20 16:36:26 -04:00
Ivo van Doorn
499a214ca2 rt2x00: Don't free register information on suspend
After suspend & resume the rt2x00 devices won't wakeup
anymore due to a broken register information setup.
The most important problem is the release of the EEPROM
buffer which is completely cleared and never read again
after the suspend.

Signed-off-by: Ivo van Doorn <IvDoorn@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2009-04-20 16:36:26 -04:00
Herbert Xu
c40af84a67 tun: Fix sk_sleep races when attaching/detaching
As the sk_sleep wait queue actually lives in tfile, which may be
detached from the tun device, bad things will happen when we use
sk_sleep after detaching.

Since the tun device is the persistent data structure here (when
requested by the user), it makes much more sense to have the wait
queue live there.  There is no reason to have it in tfile at all
since the only time we can wait is if we have a tun attached.
In fact we already have a wait queue in tun_struct, so we might
as well use it.

Reported-by: Eric W. Biederman <ebiederm@xmission.com>
Tested-by: Christian Borntraeger <borntraeger@de.ibm.com>
Tested-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-04-20 03:01:48 -07:00
Herbert Xu
9c3fea6ab0 tun: Only free a netdev when all tun descriptors are closed
The commit c70f182940 ("tun: Fix
races between tun_net_close and free_netdev") fixed a race where
an asynchronous deletion of a tun device can hose a poll(2) on
a tun fd attached to that device.

However, this came at the cost of moving the tun wait queue into
the tun file data structure.  The problem with this is that it
imposes restrictions on when and where the tun device can access
the wait queue since the tun file may change at any time due to
detaching and reattaching.

In particular, now that we need to use the wait queue on the
receive path it becomes difficult to properly synchronise this
with the detachment of the tun device.

This patch solves the original race in a different way.  Since
the race is only because the underlying memory gets freed, we
can prevent it simply by ensuring that we don't do that until
all tun descriptors ever attached to the device (even if they
have since be detached because they may still be sitting in poll)
have been closed.

This is done by using reference counting the attached tun file
descriptors.  The refcount in tun->sk has been reappropriated
for this purpose since it was already being used for that, albeit
from the opposite angle.

Note that we no longer zero tfile->tun since tun_get will return
NULL anyway after the refcount on tfile hits zero.  Instead it
represents whether this device has ever been attached to a device.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-04-20 03:01:47 -07:00