- 02 Oct, 2012 12 commits
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Mathias Krause authored
[ Upstream commit 3f68ba07 ] The HCI code fails to initialize the hci_channel member of struct sockaddr_hci and that for leaks two bytes kernel stack via the getsockname() syscall. Initialize hci_channel with 0 to avoid the info leak. Signed-off-by:
Mathias Krause <minipli@googlemail.com> Cc: Marcel Holtmann <marcel@holtmann.org> Cc: Gustavo Padovan <gustavo@padovan.org> Cc: Johan Hedberg <johan.hedberg@gmail.com> Signed-off-by:
David S. Miller <davem@davemloft.net> Signed-off-by:
Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Mathias Krause authored
[ Upstream commit e15ca9a0 ] The HCI code fails to initialize the two padding bytes of struct hci_ufilter before copying it to userland -- that for leaking two bytes kernel stack. Add an explicit memset(0) before filling the structure to avoid the info leak. Signed-off-by:
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Mathias Krause authored
[ Upstream commit 3c0c5cfd ] The ATM code fails to initialize the two padding bytes of struct sockaddr_atmpvc inserted for alignment. Add an explicit memset(0) before filling the structure to avoid the info leak. Signed-off-by:
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Mathias Krause authored
[ Upstream commit e862f1a9 ] The ATM code fails to initialize the two padding bytes of struct sockaddr_atmpvc inserted for alignment. Add an explicit memset(0) before filling the structure to avoid the info leak. Signed-off-by:
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Ben Hutchings authored
[ Upstream commit 4acd4945 ] Cong Wang reports that lockdep detected suspicious RCU usage while enabling IPV6 forwarding: [ 1123.310275] =============================== [ 1123.442202] [ INFO: suspicious RCU usage. ] [ 1123.558207] 3.6.0-rc1+ #109 Not tainted [ 1123.665204] ------------------------------- [ 1123.768254] include/linux/rcupdate.h:430 Illegal context switch in RCU read-side critical section! [ 1123.992320] [ 1123.992320] other info that might help us debug this: [ 1123.992320] [ 1124.307382] [ 1124.307382] rcu_scheduler_active = 1, debug_locks = 0 [ 1124.522220] 2 locks held by sysctl/5710: [ 1124.648364] #0: (rtnl_mutex){+.+.+.}, at: [<ffffffff81768498>] rtnl_trylock+0x15/0x17 [ 1124.882211] #1: (rcu_read_lock){.+.+.+}, at: [<ffffffff81871df8>] rcu_lock_acquire+0x0/0x29 [ 1125.085209] [ 1125.085209] stack backtrace: [ 1125.332213] Pid: 5710, comm: sysctl Not tainted 3.6.0-rc1+ #109 [ 1125.441291] Call Trace: [ 1125.545281] [<ffffffff8109d915>] lockdep_rcu_suspicious+0x109/0x112 [ 1125.667212] [<ffffffff8107c240>] rcu_preempt_sleep_check+0x45/0x47 [ 1125.781838] [<ffffffff8107c260>] __might_sleep+0x1e/0x19b [...] [ 1127.445223] [<ffffffff81757ac5>] call_netdevice_notifiers+0x4a/0x4f [...] [ 1127.772188] [<ffffffff8175e125>] dev_disable_lro+0x32/0x6b [ 1127.885174] [<ffffffff81872d26>] dev_forward_change+0x30/0xcb [ 1128.013214] [<ffffffff818738c4>] addrconf_forward_change+0x85/0xc5 [...] addrconf_forward_change() uses RCU iteration over the netdev list, which is unnecessary since it already holds the RTNL lock. We also cannot reasonably require netdevice notifier functions not to sleep. Reported-by:
Cong Wang <amwang@redhat.com> Signed-off-by:
Ben Hutchings <bhutchings@solarflare.com> Signed-off-by:
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danborkmann@iogearbox.net authored
[ Upstream commit 7f5c3e3a ] Here's a quote of the comment about the BUG macro from asm-generic/bug.h: Don't use BUG() or BUG_ON() unless there's really no way out; one example might be detecting data structure corruption in the middle of an operation that can't be backed out of. If the (sub)system can somehow continue operating, perhaps with reduced functionality, it's probably not BUG-worthy. If you're tempted to BUG(), think again: is completely giving up really the *only* solution? There are usually better options, where users don't need to reboot ASAP and can mostly shut down cleanly. In our case, the status flag of a ring buffer slot is managed from both sides, the kernel space and the user space. This means that even though the kernel side might work as expected, the user space screws up and changes this flag right between the send(2) is triggered when the flag is changed to TP_STATUS_SENDING and a given skb is destructed after some time. Then, this will hit the BUG macro. As David suggested, the best solution is to simply remove this statement since it cannot be used for kernel side internal consistency checks. I've tested it and the system still behaves /stable/ in this case, so in accordance with the above comment, we should rather remove it. Signed-off-by:
Daniel Borkmann <daniel.borkmann@tik.ee.ethz.ch> Signed-off-by:
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Alexey Khoroshilov authored
[ Upstream commit 7364e445 ] Do not leak memory by updating pointer with potentially NULL realloc return value. Found by Linux Driver Verification project (linuxtesting.org). Signed-off-by:
Alexey Khoroshilov <khoroshilov@ispras.ru> Signed-off-by:
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Wu Fengguang authored
[ Upstream commit 77f00f63 ] Fix a buffer overflow bug by removing the revision and printk. [ 22.016214] isdnloop-ISDN-driver Rev 1.11.6.7 [ 22.097508] isdnloop: (loop0) virtual card added [ 22.174400] Kernel panic - not syncing: stack-protector: Kernel stack is corrupted in: ffffffff83244972 [ 22.174400] [ 22.436157] Pid: 1, comm: swapper Not tainted 3.5.0-bisect-00018-gfa8bbb13-dirty #129 [ 22.624071] Call Trace: [ 22.720558] [<ffffffff832448c3>] ? CallcNew+0x56/0x56 [ 22.815248] [<ffffffff8222b623>] panic+0x110/0x329 [ 22.914330] [<ffffffff83244972>] ? isdnloop_init+0xaf/0xb1 [ 23.014800] [<ffffffff832448c3>] ? CallcNew+0x56/0x56 [ 23.090763] [<ffffffff8108e24b>] __stack_chk_fail+0x2b/0x30 [ 23.185748] [<ffffffff83244972>] isdnloop_init+0xaf/0xb1 Signed-off-by:
Fengguang Wu <fengguang.wu@intel.com> Signed-off-by:
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Hiroaki SHIMODA authored
[ Upstream commit 696ecdc1 ] gact_rand array is accessed by gact->tcfg_ptype whose value is assumed to less than MAX_RAND, but any range checks are not performed. So add a check in tcf_gact_init(). And in tcf_gact(), we can reduce a branch. Signed-off-by:
Hiroaki SHIMODA <shimoda.hiroaki@gmail.com> Signed-off-by:
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Ben Hutchings authored
[ Upstream commit 1485348d ] Cache the device gso_max_segs in sock::sk_gso_max_segs and use it to limit the size of TSO skbs. This avoids the need to fall back to software GSO for local TCP senders. Signed-off-by:
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Ben Hutchings authored
[ Upstream commit 7e6d06f0 ] Currently an skb requiring TSO may not fit within a minimum-size TX queue. The TX queue selected for the skb may stall and trigger the TX watchdog repeatedly (since the problem skb will be retried after the TX reset). This issue is designated as CVE-2012-3412. Set the maximum number of TSO segments for our devices to 100. This should make no difference to behaviour unless the actual MSS is less than about 700. Increase the minimum TX queue size accordingly to allow for 2 worst-case skbs, so that there will definitely be space to add an skb after we wake a queue. To avoid invalidating existing configurations, change efx_ethtool_set_ringparam() to fix up values that are too small rather than returning -EINVAL. Signed-off-by:
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Ben Hutchings authored
[ Upstream commit 30b678d8 ] A peer (or local user) may cause TCP to use a nominal MSS of as little as 88 (actual MSS of 76 with timestamps). Given that we have a sufficiently prodigious local sender and the peer ACKs quickly enough, it is nevertheless possible to grow the window for such a connection to the point that we will try to send just under 64K at once. This results in a single skb that expands to 861 segments. In some drivers with TSO support, such an skb will require hundreds of DMA descriptors; a substantial fraction of a TX ring or even more than a full ring. The TX queue selected for the skb may stall and trigger the TX watchdog repeatedly (since the problem skb will be retried after the TX reset). This particularly affects sfc, for which the issue is designated as CVE-2012-3412. Therefore: 1. Add the field net_device::gso_max_segs holding the device-specific limit. 2. In netif_skb_features(), if the number of segments is too high then mask out GSO features to force fall back to software GSO. Signed-off-by:
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- 14 Sep, 2012 28 commits
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Greg Kroah-Hartman authored
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Luca Tettamanti authored
commit 43ca6cb2 upstream. The old interface is bugged and reads the wrong sensor when retrieving the reading for the chassis fan (it reads the CPU sensor); the new interface works fine. Reported-by:
Göran Uddeborg <goeran@uddeborg.se> Tested-by:
Luca Tettamanti <kronos.it@gmail.com> Signed-off-by:
Guenter Roeck <linux@roeck-us.net> Signed-off-by:
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Mathias Krause authored
commit 276bdb82 upstream. ccid_hc_rx_getsockopt() and ccid_hc_tx_getsockopt() might be called with a NULL ccid pointer leading to a NULL pointer dereference. This could lead to a privilege escalation if the attacker is able to map page 0 and prepare it with a fake ccid_ops pointer. Signed-off-by:
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Mel Gorman authored
commit bba3d8c3 upstream. The following build error occured during a parisc build with swap-over-NFS patches applied. net/core/sock.c:274:36: error: initializer element is not constant net/core/sock.c:274:36: error: (near initialization for 'memalloc_socks') net/core/sock.c:274:36: error: initializer element is not constant Dave Anglin says: > Here is the line in sock.i: > > struct static_key memalloc_socks = ((struct static_key) { .enabled = > ((atomic_t) { (0) }) }); The above line contains two compound literals. It also uses a designated initializer to initialize the field enabled. A compound literal is not a constant expression. The location of the above statement isn't fully clear, but if a compound literal occurs outside the body of a function, the initializer list must consist of constant expressions. Reported-by:
Mel Gorman <mgorman@suse.de> Signed-off-by:
James Bottomley <JBottomley@Parallels.com> Signed-off-by:
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Dave Airlie authored
commit c4903429 upstream. This will cause udev to load vmwgfx instead of waiting for X to do it. Reviewed-by:
Jakob Bornecrantz <jakob@vmware.com> Signed-off-by:
Dave Airlie <airlied@redhat.com> Signed-off-by:
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Dmitry Torokhov authored
commit 7b125b94 upstream. They all define their chassis type as "Other" and therefore are not categorized as "laptops" by the driver, which tries to perform AUX IRQ delivery test which fails and causes touchpad not working. Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=42620Signed-off-by:
Dmitry Torokhov <dmitry.torokhov@gmail.com> Signed-off-by:
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Miklos Szeredi authored
commit c9e67d48 upstream. In some cases fuse_retrieve() would return a short byte count if offset was non-zero. The data returned was correct, though. Signed-off-by:
Miklos Szeredi <mszeredi@suse.cz> Signed-off-by:
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Jan Kara authored
commit 156bddd8 upstream. Code tracking when transaction needs to be committed on fdatasync(2) forgets to handle a situation when only inode's i_size is changed. Thus in such situations fdatasync(2) doesn't force transaction with new i_size to disk and that can result in wrong i_size after a crash. Fix the issue by updating inode's i_datasync_tid whenever its size is updated. Reported-by:
Kristian Nielsen <knielsen@knielsen-hq.org> Signed-off-by:
Jan Kara <jack@suse.cz> Signed-off-by:
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Jan Kara authored
commit 9c2fc0de upstream. When a file is stored in ICB (inode), we overwrite part of the file, and the page containing file's data is not in page cache, we end up corrupting file's data by overwriting them with zeros. The problem is we use simple_write_begin() which simply zeroes parts of the page which are not written to. The problem has been introduced by be021ee4 (udf: convert to new aops). Fix the problem by providing a ->write_begin function which makes the page properly uptodate. Reported-by:
Ian Abbott <abbotti@mev.co.uk> Signed-off-by:
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James Bottomley authored
commit 14216561 upstream. This is a particularly nasty SCSI ATA Translation Layer (SATL) problem. SAT-2 says (section 8.12.2) if the device is in the stopped state as the result of processing a START STOP UNIT command (see 9.11), then the SATL shall terminate the TEST UNIT READY command with CHECK CONDITION status with the sense key set to NOT READY and the additional sense code of LOGICAL UNIT NOT READY, INITIALIZING COMMAND REQUIRED; mpt2sas internal SATL seems to implement this. The result is very confusing standby behaviour (using hdparm -y). If you suspend a drive and then send another command, usually it wakes up. However, if the next command is a TEST UNIT READY, the SATL sees that the drive is suspended and proceeds to follow the SATL rules for this, returning NOT READY to all subsequent commands. This means that the ordering of TEST UNIT READY is crucial: if you send TUR and then a command, you get a NOT READY to both back. If you send a command and then a TUR, you get GOOD status because the preceeding command woke the drive. This bit us badly because commit 85ef06d1 Author: Tejun Heo <tj@kernel.org> Date: Fri Jul 1 16:17:47 2011 +0200 block: flush MEDIA_CHANGE from drivers on close(2) Changed our ordering on TEST UNIT READY commands meaning that SATA drives connected to an mpt2sas now suspend and refuse to wake (because the mpt2sas SATL sees the suspend *before* the drives get awoken by the next ATA command) resulting in lots of failed commands. The standard is completely nuts forcing this inconsistent behaviour, but we have to work around it. The fix for this is twofold: 1. Set the allow_restart flag so we wake the drive when we see it has been suspended 2. Return all TEST UNIT READY status directly to the mid layer without any further error handling which prevents us causing error handling which may offline the device just because of a media check TUR. Reported-by:
Matthias Prager <linux@matthiasprager.de> Signed-off-by:
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sreekanth.reddy@lsi.com authored
SCSI: mpt2sas: Fix for Driver oops, when loading driver with max_queue_depth command line option to a very small value commit 338b131a upstream. If the specified max_queue_depth setting is less than the expected number of internal commands, then driver will calculate the queue depth size to a negitive number. This negitive number is actually a very large number because variable is unsigned 16bit integer. So, the driver will ask for a very large amount of memory for message frames and resulting into oops as memory allocation routines will not able to handle such a large request. So, in order to limit this kind of oops, The driver need to set the max_queue_depth to a scsi mid layer's can_queue value. Then the overall message frames required for IO is minimum of either (max_queue_depth plus internal commands) or the IOC global credits. Signed-off-by:
Sreekanth Reddy <sreekanth.reddy@lsi.com> Signed-off-by:
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Kashyap Desai authored
commit bd8d6dd4 upstream. The following patch moves the poll_aen_lock initializer from megasas_probe_one() to megasas_init(). This prevents a crash when a user loads the driver and tries to issue a poll() system call on the ioctl interface with no adapters present. Signed-off-by:
Kashyap Desai <Kashyap.Desai@lsi.com> Signed-off-by:
Adam Radford <aradford@gmail.com> Signed-off-by:
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Dave Jones authored
commit 80de7c31 upstream. Trivially triggerable, found by trinity: kernel BUG at mm/mempolicy.c:2546! Process trinity-child2 (pid: 23988, threadinfo ffff88010197e000, task ffff88007821a670) Call Trace: show_numa_map+0xd5/0x450 show_pid_numa_map+0x13/0x20 traverse+0xf2/0x230 seq_read+0x34b/0x3e0 vfs_read+0xac/0x180 sys_pread64+0xa2/0xc0 system_call_fastpath+0x1a/0x1f RIP: mpol_to_str+0x156/0x360 Signed-off-by:
Dave Jones <davej@redhat.com> Signed-off-by:
Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by:
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Anton Blanchard authored
commit 71433285 upstream. During a context switch we always restore the per thread DSCR value. If we aren't doing explicit DSCR management (ie thread.dscr_inherit == 0) and the default DSCR changed while the process has been sleeping we end up with the wrong value. Check thread.dscr_inherit and select the default DSCR or per thread DSCR as required. This was found with the following test case, when running with more threads than CPUs (ie forcing context switching): http://ozlabs.org/~anton/junkcode/dscr_default_test.c With the four patches applied I can run a combination of all test cases successfully at the same time: http://ozlabs.org/~anton/junkcode/dscr_default_test.c http://ozlabs.org/~anton/junkcode/dscr_explicit_test.c http://ozlabs.org/~anton/junkcode/dscr_inherit_test.cSigned-off-by:
Anton Blanchard <anton@samba.org> Signed-off-by:
Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by:
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Anton Blanchard authored
commit 1021cb26 upstream. If the default DSCR is non zero we set thread.dscr_inherit in copy_thread() meaning the new thread and all its children will ignore future updates to the default DSCR. This is not intended and is a change in behaviour that a number of our users have hit. We just need to inherit thread.dscr and thread.dscr_inherit from the parent which ends up being much simpler. This was found with the following test case: http://ozlabs.org/~anton/junkcode/dscr_default_test.cSigned-off-by:
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Sven Schnelle authored
commit 99f347ca upstream. If a device specifies zero endpoints in its interface descriptor, the kernel oopses in acm_probe(). Even though that's clearly an invalid descriptor, we should test wether we have all endpoints. This is especially bad as this oops can be triggered by just plugging a USB device in. Signed-off-by:
Sven Schnelle <svens@stackframe.org> Signed-off-by:
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Greg Kroah-Hartman authored
commit d04dbd1c upstream. This structure needs to always stick around, even if CONFIG_HOTPLUG is disabled, otherwise we can oops when trying to probe a device that was added after the structure is thrown away. Thanks to Fengguang Wu and Bjørn Mork for tracking this issue down. Reported-by:
Bjørn Mork <bjorn@mork.no> CC: Mauro Carvalho Chehab <mchehab@infradead.org> CC: Michael Krufky <mkrufky@linuxtv.org> CC: Paul Gortmaker <paul.gortmaker@windriver.com> CC: Doron Cohen <doronc@siano-ms.com> Signed-off-by:
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Greg Kroah-Hartman authored
commit a3433179 upstream. This structure needs to always stick around, even if CONFIG_HOTPLUG is disabled, otherwise we can oops when trying to probe a device that was added after the structure is thrown away. Thanks to Fengguang Wu and Bjørn Mork for tracking this issue down. Reported-by:
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Greg Kroah-Hartman authored
commit b9c4167c upstream. This structure needs to always stick around, even if CONFIG_HOTPLUG is disabled, otherwise we can oops when trying to probe a device that was added after the structure is thrown away. Thanks to Fengguang Wu and Bjørn Mork for tracking this issue down. Reported-by:
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Greg Kroah-Hartman authored
commit e694d518 upstream. This structure needs to always stick around, even if CONFIG_HOTPLUG is disabled, otherwise we can oops when trying to probe a device that was added after the structure is thrown away. Thanks to Fengguang Wu and Bjørn Mork for tracking this issue down. Reported-by:
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Hugh Dickins authored
commit 676ce6d5 upstream. Commit 91f68c89 ("block: fix infinite loop in __getblk_slow") is not good: a successful call to grow_buffers() cannot guarantee that the page won't be reclaimed before the immediate next call to __find_get_block(), which is why there was always a loop there. Yesterday I got "EXT4-fs error (device loop0): __ext4_get_inode_loc:3595: inode #19278: block 664: comm cc1: unable to read itable block" on console, which pointed to this commit. I've been trying to bisect for weeks, why kbuild-on-ext4-on-loop-on-tmpfs sometimes fails from a missing header file, under memory pressure on ppc G5. I've never seen this on x86, and I've never seen it on 3.5-rc7 itself, despite that commit being in there: bisection pointed to an irrelevant pinctrl merge, but hard to tell when failure takes between 18 minutes and 38 hours (but so far it's happened quicker on 3.6-rc2). (I've since found such __ext4_get_inode_loc errors in /var/log/messages from previous weeks: why the message never appeared on console until yesterday morning is a mystery for another day.) Revert 91f68c89, restoring __getblk_slow() to how it was (plus a checkpatch nitfix). Simplify the interface between grow_buffers() and grow_dev_page(), and avoid the infinite loop beyond end of device by instead checking init_page_buffers()'s end_block there (I presume that's more efficient than a repeated call to blkdev_max_block()), returning -ENXIO to __getblk_slow() in that case. And remove akpm's ten-year-old "__getblk() cannot fail ... weird" comment, but that is worrying: are all users of __getblk() really now prepared for a NULL bh beyond end of device, or will some oops?? Signed-off-by:
Hugh Dickins <hughd@google.com> Signed-off-by:
Jens Axboe <axboe@kernel.dk> Signed-off-by:
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Rafael J. Wysocki authored
commit 0b68c8e2 upstream. Commit dbf0e4c7 (PCI: EHCI: fix crash during suspend on ASUS computers) added a workaround for an ASUS suspend issue related to USB EHCI and a bug in a number of ASUS BIOSes that attempt to shut down the EHCI controller during system suspend if its PCI command register doesn't contain 0 at that time. It turns out that the same workaround is necessary in the analogous hibernation code path, so add it. References: https://bugzilla.kernel.org/show_bug.cgi?id=45811Reported-and-tested-by:
Oleksij Rempel <bug-track@fisher-privat.net> Signed-off-by:
Rafael J. Wysocki <rjw@sisk.pl> Signed-off-by:
Bjorn Helgaas <bhelgaas@google.com> Signed-off-by:
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Lorenzo Bianconi authored
commit e1352fde upstream. ath_rx_tasklet() calls ath9k_rx_skb_preprocess() and ath9k_rx_skb_postprocess() in a loop over the received frames. The decrypt_error flag is initialized to false just outside ath_rx_tasklet() loop. ath9k_rx_accept(), called by ath9k_rx_skb_preprocess(), only sets decrypt_error to true and never to false. Then ath_rx_tasklet() calls ath9k_rx_skb_postprocess() and passes decrypt_error to it. So, after a decryption error, in ath9k_rx_skb_postprocess(), we can have a leftover value from another processed frame. In that case, the frame will not be marked with RX_FLAG_DECRYPTED even if it is decrypted correctly. When using CCMP encryption this issue can lead to connection stuck because of CCMP PN corruption and a waste of CPU time since mac80211 tries to decrypt an already deciphered frame with ieee80211_aes_ccm_decrypt. Fix the issue initializing decrypt_error flag at the begging of the ath_rx_tasklet() loop. Signed-off-by:
Lorenzo Bianconi <lorenzo.bianconi83@gmail.com> Signed-off-by:
John W. Linville <linville@tuxdriver.com> Signed-off-by:
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Alex Deucher authored
commit 4f81f986 upstream. We need it in the radeon drm module to fetch and verify the vbios image on UEFI systems. Signed-off-by:
Alex Deucher <alexander.deucher@amd.com> Signed-off-by:
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Stephen M. Cameron authored
commit b0cf0b11 upstream. Delete code which sets SCSI status incorrectly as it's already been set correctly above this incorrect code. The bug was introduced in 2009 by commit b0e15f6d ("cciss: fix typo that causes scsi status to be lost.") Signed-off-by:
Stephen M. Cameron <scameron@beardog.cce.hp.com> Reported-by:
Roel van Meer <roel.vanmeer@bokxing.nl> Tested-by:
Andrew Morton <akpm@linux-foundation.org> Signed-off-by:
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J. Bruce Fields authored
commit f06f00a2 upstream. svc_tcp_sendto sets XPT_CLOSE if we fail to transmit the entire reply. However, the XPT_CLOSE won't be acted on immediately. Meanwhile other threads could send further replies before the socket is really shut down. This can manifest as data corruption: for example, if a truncated read reply is followed by another rpc reply, that second reply will look to the client like further read data. Symptoms were data corruption preceded by svc_tcp_sendto logging something like kernel: rpc-srv/tcp: nfsd: sent only 963696 when sending 1048708 bytes - shutting down socket Reported-by:
Malahal Naineni <malahal@us.ibm.com> Tested-by:
J. Bruce Fields <bfields@redhat.com> Signed-off-by:
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J. Bruce Fields authored
commit d10f27a7 upstream. The rpc server tries to ensure that there will be room to send a reply before it receives a request. It does this by tracking, in xpt_reserved, an upper bound on the total size of the replies that is has already committed to for the socket. Currently it is adding in the estimate for a new reply *before* it checks whether there is space available. If it finds that there is not space, it then subtracts the estimate back out. This may lead the subsequent svc_xprt_enqueue to decide that there is space after all. The results is a svc_recv() that will repeatedly return -EAGAIN, causing server threads to loop without doing any actual work. Reported-by:
Michael Tokarev <mjt@tls.msk.ru> Tested-by:
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J. Bruce Fields authored
commit be1e4444 upstream. Examination of svc_tcp_clear_pages shows that it assumes sk_tcplen is consistent with sk_pages[] (in particular, sk_pages[n] can't be NULL if sk_tcplen would lead us to expect n pages of data). svc_tcp_restore_pages zeroes out sk_pages[] while leaving sk_tcplen. This is OK, since both functions are serialized by XPT_BUSY. However, that means the inconsistency must be repaired before dropping XPT_BUSY. Therefore we should be ensuring that svc_tcp_save_pages repairs the problem before exiting svc_tcp_recv_record on error. Symptoms were a BUG() in svc_tcp_clear_pages. Signed-off-by:
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