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ath9k: fix stale pointers potentially causing access to free'd skbs commit 8c6e309 upstream. bf->bf_next is only while buffers are chained as part of an A-MPDU in the tx queue. When a tid queue is flushed (e.g. on tearing down an aggregation session), frames can be enqueued again as normal transmission, without bf_next being cleared. This can lead to the old pointer being dereferenced again later. This patch might fix crashes and "Failed to stop TX DMA!" messages. Signed-off-by: Felix Fietkau <[email protected]> Signed-off-by: John W. Linville <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> rt2800: validate step value for temperature compensation commit bf7e1ab upstream. Some hardware has correct (!= 0xff) value of tssi_bounds[4] in the EEPROM, but step is equal to 0xff. This results on ridiculous delta calculations and completely broke TX power settings. Reported-and-tested-by: Pavel Lucik <[email protected]> Signed-off-by: Stanislaw Gruszka <[email protected]> Acked-by: Ivo van Doorn <[email protected]> Signed-off-by: John W. Linville <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> target: Don't return success from module_init() if setup fails commit 0d0f9df upstream. If the call to core_dev_release_virtual_lun0() fails, then nothing sets ret to anything other than 0, so even though everything is torn down and freed, target_core_init_configfs() will seem to succeed and the module will be loaded. Fix this by passing the return value on up the chain. Signed-off-by: Roland Dreier <[email protected]> Signed-off-by: Nicholas Bellinger <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> cfg80211: fix antenna gain handling commit c4a9faf upstream. No driver initializes chan->max_antenna_gain to something sensible, and the only place where it is being used right now is inside ath9k. This leads to ath9k potentially using less tx power than it can use, which can decrease performance/range in some rare cases. Rather than going through every single driver, this patch initializes chan->orig_mag in wiphy_register(), ignoring whatever value the driver left in there. If a driver for some reason wishes to limit it independent from regulatory rulesets, it can do so internally. Signed-off-by: Felix Fietkau <[email protected]> Signed-off-by: Johannes Berg <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> wireless: drop invalid mesh address extension frames commit 7dd111e upstream. The mesh header can have address extension by a 4th or a 5th and 6th address, but never both. Drop such frames in 802.11 -> 802.3 conversion along with any frames that have the wrong extension. Reviewed-by: Javier Cardona <[email protected]> Signed-off-by: Johannes Berg <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> mac80211: don't inspect Sequence Control field on control frames commit f7fbf70 upstream. Per IEEE Std. 802.11-2012, Sec 8.2.4.4.1, the sequence Control field is not present in control frames. We noticed this problem when processing Block Ack Requests. Signed-off-by: Javier Cardona <[email protected]> Signed-off-by: Javier Lopez <[email protected]> Signed-off-by: Johannes Berg <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> DRM/Radeon: Fix Load Detection on legacy primary DAC. commit 83325d0 upstream. An uninitialized variable led to broken load detection. Signed-off-by: Egbert Eich <[email protected]> Signed-off-by: Alex Deucher <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> mac80211: check management frame header length commit 4a4f1a5 upstream. Due to pskb_may_pull() checking the skb length, all non-management frames are checked on input whether their 802.11 header is fully present. Also add that check for management frames and remove a check that is now duplicate. This prevents accessing skb data beyond the frame end. Signed-off-by: Johannes Berg <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> mac80211: fix SSID copy on IBSS JOIN commit badecb0 upstream. The 'ssid' field of the cfg80211_ibss_params is a u8 pointer and its length is likely to be less than IEEE80211_MAX_SSID_LEN most of the time. This patch fixes the ssid copy in ieee80211_ibss_join() by using the SSID length to prevent it from reading beyond the string. Signed-off-by: Antonio Quartulli <[email protected]> [rewrapped commit message, small rewording] Signed-off-by: Johannes Berg <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> nfsv3: Make v3 mounts fail with ETIMEDOUTs instead EIO on mountd timeouts commit acce94e upstream. In very busy v3 environment, rpc.mountd can respond to the NULL procedure but not the MNT procedure in a timely manner causing the MNT procedure to time out. The problem is the mount system call returns EIO which causes the mount to fail, instead of ETIMEDOUT, which would cause the mount to be retried. This patch sets the RPC_TASK_SOFT|RPC_TASK_TIMEOUT flags to the rpc_call_sync() call in nfs_mount() which causes ETIMEDOUT to be returned on timed out connections. Signed-off-by: Steve Dickson <[email protected]> Signed-off-by: Trond Myklebust <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> nfs: Show original device name verbatim in /proc/*/mount{s,info} commit 97a5486 upstream. Since commit c7f404b ('vfs: new superblock methods to override /proc/*/mount{s,info}'), nfs_path() is used to generate the mounted device name reported back to userland. nfs_path() always generates a trailing slash when the given dentry is the root of an NFS mount, but userland may expect the original device name to be returned verbatim (as it used to be). Make this canonicalisation optional and change the callers accordingly. [[email protected]: use flag instead of bool argument] Reported-and-tested-by: Chris Hiestand <[email protected]> Reference: http://bugs.debian.org/669314 Signed-off-by: Ben Hutchings <[email protected]> Signed-off-by: Jonathan Nieder <[email protected]> Signed-off-by: Trond Myklebust <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> NFSv4: nfs4_locku_done must release the sequence id commit 2b1bc30 upstream. If the state recovery machinery is triggered by the call to nfs4_async_handle_error() then we can deadlock. Signed-off-by: Trond Myklebust <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> nfsd: add get_uint for u32's commit a007c4c upstream. I don't think there's a practical difference for the range of values these interfaces should see, but it would be safer to be unambiguous. Signed-off-by: J. Bruce Fields <[email protected]> Cc: Sasha Levin <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> NFS: fix bug in legacy DNS resolver. commit 8d96b10 upstream. The DNS resolver's use of the sunrpc cache involves a 'ttl' number (relative) rather that a timeout (absolute). This confused me when I wrote commit c5b29f8 "sunrpc: use seconds since boot in expiry cache" and I managed to break it. The effect is that any TTL is interpreted as 0, and nothing useful gets into the cache. This patch removes the use of get_expiry() - which really expects an expiry time - and uses get_uint() instead, treating the int correctly as a ttl. This fixes a regression that has been present since 2.6.37, causing certain NFS accesses in certain environments to incorrectly fail. Reported-by: Chuck Lever <[email protected]> Tested-by: Chuck Lever <[email protected]> Signed-off-by: NeilBrown <[email protected]> Signed-off-by: Trond Myklebust <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> NFS: Fix Oopses in nfs_lookup_revalidate and nfs4_lookup_revalidate [Fixed upstream as part of 0b728e1, but that's a much larger patch, this is only the nfs portion backported as needed.] Fix the following Oops in 3.5.1: BUG: unable to handle kernel NULL pointer dereference at 0000000000000038 IP: [<ffffffffa03789cd>] nfs_lookup_revalidate+0x2d/0x480 [nfs] PGD 337c63067 PUD 0 Oops: 0000 [Flemmard#1] SMP CPU 5 Modules linked in: nfs fscache nfsd lockd nfs_acl auth_rpcgss sunrpc af_packet binfmt_misc cpufreq_conservative cpufreq_userspace cpufreq_powersave dm_mod acpi_cpufreq mperf coretemp gpio_ich kvm_intel joydev kvm ioatdma hid_generic igb lpc_ich i7core_edac edac_core ptp serio_raw dca pcspkr i2c_i801 mfd_core sg pps_core usbhid crc32c_intel microcode button autofs4 uhci_hcd ttm drm_kms_helper drm i2c_algo_bit sysimgblt sysfillrect syscopyarea ehci_hcd usbcore usb_common scsi_dh_rdac scsi_dh_emc scsi_dh_hp_sw scsi_dh_alua scsi_dh edd fan ata_piix thermal processor thermal_sys Pid: 30431, comm: java Not tainted 3.5.1-2-default Flemmard#1 Supermicro X8DTT/X8DTT RIP: 0010:[<ffffffffa03789cd>] [<ffffffffa03789cd>] nfs_lookup_revalidate+0x2d/0x480 [nfs] RSP: 0018:ffff8801b418bd38 EFLAGS: 00010292 RAX: 00000000fffffff6 RBX: ffff88032016d800 RCX: 0000000000000020 RDX: ffffffff00000000 RSI: 0000000000000000 RDI: ffff8801824a7b00 RBP: ffff8801b418bdf8 R08: 7fffff0034323030 R09: fffffffff04c03ed R10: ffff8801824a7b00 R11: 0000000000000002 R12: ffff8801824a7b00 R13: ffff8801824a7b00 R14: 0000000000000000 R15: ffff8803201725d0 FS: 00002b53a46cb700(0000) GS:ffff88033fc20000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000038 CR3: 000000020a426000 CR4: 00000000000007e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Process java (pid: 30431, threadinfo ffff8801b418a000, task ffff8801b5d20600) Stack: ffff8801b418be44 ffff88032016d800 ffff8801b418bdf8 0000000000000000 ffff8801824a7b00 ffff8801b418bdd7 ffff8803201725d0 ffffffff8116a9c0 ffff8801b5c38dc0 0000000000000007 ffff88032016d800 0000000000000000 Call Trace: [<ffffffff8116a9c0>] lookup_dcache+0x80/0xe0 [<ffffffff8116aa43>] __lookup_hash+0x23/0x90 [<ffffffff8116b4a5>] lookup_one_len+0xc5/0x100 [<ffffffffa03869a3>] nfs_sillyrename+0xe3/0x210 [nfs] [<ffffffff8116cadf>] vfs_unlink.part.25+0x7f/0xe0 [<ffffffff8116f22c>] do_unlinkat+0x1ac/0x1d0 [<ffffffff815717b9>] system_call_fastpath+0x16/0x1b [<00002b5348b5f527>] 0x2b5348b5f526 Code: ec 38 b8 f6 ff ff ff 4c 89 64 24 18 4c 89 74 24 28 49 89 fc 48 89 5c 24 08 48 89 6c 24 10 49 89 f6 4c 89 6c 24 20 4c 89 7c 24 30 <f6> 46 38 40 0f 85 d1 00 00 00 e8 c4 c4 df e0 48 8b 58 30 49 89 RIP [<ffffffffa03789cd>] nfs_lookup_revalidate+0x2d/0x480 [nfs] RSP <ffff8801b418bd38> CR2: 0000000000000038 ---[ end trace 845113ed191985dd ]--- This Oops affects 3.5 kernels and older, and is due to lookup_one_len() calling down to the dentry revalidation code with a NULL pointer to struct nameidata. It is fixed upstream by commit 0b728e1 (stop passing nameidata * to ->d_revalidate()) Reported-by: Richard Ems <[email protected]> Signed-off-by: Trond Myklebust <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> drm: restore open_count if drm_setup fails commit 0f1cb1b upstream. If drm_setup (called at first open) fails, the whole open call has failed, so we should not keep the open_count incremented. Signed-off-by: Ilija Hadzic <[email protected]> Reviewed-by: Thomas Hellstrom <[email protected]> Signed-off-by: Dave Airlie <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> hwmon: (w83627ehf) Force initial bank selection commit 3300fb4 upstream. Don't assume bank 0 is selected at device probe time. This may not be the case. Force bank selection at first register access to guarantee that we read the right registers upon driver loading. Signed-off-by: Jean Delvare <[email protected]> Reviewed-by: Guenter Roeck <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> ALSA: PCM: Fix some races at disconnection commit 9b0573c upstream. Fix races at PCM disconnection: - while a PCM device is being opened or closed - while the PCM state is being changed without lock in prepare, hw_params, hw_free ops Reported-by: Matthieu CASTET <[email protected]> Signed-off-by: Takashi Iwai <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> ALSA: usb-audio: Fix races at disconnection commit 978520b upstream. Close some races at disconnection of a USB audio device by adding the chip->shutdown_mutex and chip->shutdown check at appropriate places. The spots to put bandaids are: - PCM prepare, hw_params and hw_free - where the usb device is accessed for communication or get speed, in mixer.c and others; the device speed is now cached in subs->speed instead of accessing to chip->dev The accesses in PCM open and close don't need the mutex protection because these are already handled in the core PCM disconnection code. The autosuspend/autoresume codes are still uncovered by this patch because of possible mutex deadlocks. They'll be covered by the upcoming change to rwsem. Also the mixer codes are untouched, too. These will be fixed in another patch, too. Reported-by: Matthieu CASTET <[email protected]> Signed-off-by: Takashi Iwai <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> ALSA: usb-audio: Use rwsem for disconnect protection commit 34f3c89 upstream. Replace mutex with rwsem for codec->shutdown protection so that concurrent accesses are allowed. Also add the protection to snd_usb_autosuspend() and snd_usb_autoresume(), too. Reported-by: Matthieu CASTET <[email protected]> Signed-off-by: Takashi Iwai <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> ALSA: usb-audio: Fix races at disconnection in mixer_quirks.c commit 888ea7d upstream. Similar like the previous commit, cover with chip->shutdown_rwsem and chip->shutdown checks. Reported-by: Matthieu CASTET <[email protected]> Signed-off-by: Takashi Iwai <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> ALSA: Add a reference counter to card instance commit a0830db upstream. For more strict protection for wild disconnections, a refcount is introduced to the card instance, and let it up/down when an object is referred via snd_lookup_*() in the open ops. The free-after-last-close check is also changed to check this refcount instead of the empty list, too. Reported-by: Matthieu CASTET <[email protected]> Signed-off-by: Takashi Iwai <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> ALSA: Avoid endless sleep after disconnect commit 0914f79 upstream. When disconnect callback is called, each component should wake up sleepers and check card->shutdown flag for avoiding the endless sleep blocking the proper resource release. Signed-off-by: Takashi Iwai <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> sctp: fix call to SCTP_CMD_PROCESS_SACK in sctp_cmd_interpreter() [ Upstream commit f6e80ab ] Bug introduced by commit edfee03 (sctp: check src addr when processing SACK to update transport state) Signed-off-by: Zijie Pan <[email protected]> Signed-off-by: Nicolas Dichtel <[email protected]> Acked-by: Vlad Yasevich <[email protected]> Signed-off-by: David S. Miller <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> netlink: use kfree_rcu() in netlink_release() [ Upstream commit 6d772ac ] On some suspend/resume operations involving wimax device, we have noticed some intermittent memory corruptions in netlink code. Stéphane Marchesin tracked this corruption in netlink_update_listeners() and suggested a patch. It appears netlink_release() should use kfree_rcu() instead of kfree() for the listeners structure as it may be used by other cpus using RCU protection. netlink_release() must set to NULL the listeners pointer when it is about to be freed. Also have to protect netlink_update_listeners() and netlink_has_listeners() if listeners is NULL. Add a nl_deref_protected() lockdep helper to properly document which locks protects us. Reported-by: Jonathan Kliegman <[email protected]> Signed-off-by: Eric Dumazet <[email protected]> Cc: Stéphane Marchesin <[email protected]> Cc: Sam Leffler <[email protected]> Signed-off-by: David S. Miller <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> tcp: fix FIONREAD/SIOCINQ [ Upstream commit a3374c4 ] tcp_ioctl() tries to take into account if tcp socket received a FIN to report correct number bytes in receive queue. But its flaky because if the application ate the last skb, we return 1 instead of 0. Correct way to detect that FIN was received is to test SOCK_DONE. Reported-by: Elliot Hughes <[email protected]> Signed-off-by: Eric Dumazet <[email protected]> Cc: Neal Cardwell <[email protected]> Cc: Tom Herbert <[email protected]> Signed-off-by: David S. Miller <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> ipv6: Set default hoplimit as zero. [ Upstream commit 14edd87 ] Commit a02e4b7(Demark default hoplimit as zero) only changes the hoplimit checking condition and default value in ip6_dst_hoplimit, not zeros all hoplimit default value. Keep the zeroing ip6_template_metrics[RTAX_HOPLIMIT - 1] to force it as const, cause as a37e6e3(net: force dst_default_metrics to const section) Signed-off-by: Li RongQing <[email protected]> Signed-off-by: David S. Miller <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> net: usb: Fix memory leak on Tx data path [ Upstream commit 39707c2 ] Driver anchors the tx urbs and defers the urb submission if a transmit request comes when the interface is suspended. Anchoring urb increments the urb reference count. These deferred urbs are later accessed by calling usb_get_from_anchor() for submission during interface resume. usb_get_from_anchor() unanchors the urb but urb reference count remains same. This causes the urb reference count to remain non-zero after usb_free_urb() gets called and urb never gets freed. Hence call usb_put_urb() after anchoring the urb to properly balance the reference count for these deferred urbs. Also, unanchor these deferred urbs during disconnect, to free them up. Signed-off-by: Hemant Kumar <[email protected]> Acked-by: Oliver Neukum <[email protected]> Signed-off-by: David S. Miller <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> net: fix divide by zero in tcp algorithm illinois [ Upstream commit 8f363b7 ] Reading TCP stats when using TCP Illinois congestion control algorithm can cause a divide by zero kernel oops. The division by zero occur in tcp_illinois_info() at: do_div(t, ca->cnt_rtt); where ca->cnt_rtt can become zero (when rtt_reset is called) Steps to Reproduce: 1. Register tcp_illinois: # sysctl -w net.ipv4.tcp_congestion_control=illinois 2. Monitor internal TCP information via command "ss -i" # watch -d ss -i 3. Establish new TCP conn to machine Either it fails at the initial conn, or else it needs to wait for a loss or a reset. This is only related to reading stats. The function avg_delay() also performs the same divide, but is guarded with a (ca->cnt_rtt > 0) at its calling point in update_params(). Thus, simply fix tcp_illinois_info(). Function tcp_illinois_info() / get_info() is called without socket lock. Thus, eliminate any race condition on ca->cnt_rtt by using a local stack variable. Simply reuse info.tcpv_rttcnt, as its already set to ca->cnt_rtt. Function avg_delay() is not affected by this race condition, as its called with the socket lock. Cc: Petr Matousek <[email protected]> Signed-off-by: Jesper Dangaard Brouer <[email protected]> Acked-by: Eric Dumazet <[email protected]> Acked-by: Stephen Hemminger <[email protected]> Signed-off-by: David S. Miller <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> l2tp: fix oops in l2tp_eth_create() error path [ Upstream commit 7893363 ] When creating an L2TPv3 Ethernet session, if register_netdev() should fail for any reason (for example, automatic naming for "l2tpeth%d" interfaces hits the 32k-interface limit), the netdev is freed in the error path. However, the l2tp_eth_sess structure's dev pointer is left uncleared, and this results in l2tp_eth_delete() then attempting to unregister the same netdev later in the session teardown. This results in an oops. To avoid this, clear the session dev pointer in the error path. Signed-off-by: Tom Parkin <[email protected]> Signed-off-by: David S. Miller <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> ipv6: send unsolicited neighbour advertisements to all-nodes [ Upstream commit 60713a0 ] As documented in RFC4861 (Neighbor Discovery for IP version 6) 7.2.6., unsolicited neighbour advertisements should be sent to the all-nodes multicast address. Signed-off-by: Hannes Frederic Sowa <[email protected]> Signed-off-by: David S. Miller <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> futex: Handle futex_pi OWNER_DIED take over correctly commit 59fa624 upstream. Siddhesh analyzed a failure in the take over of pi futexes in case the owner died and provided a workaround. See: http://sourceware.org/bugzilla/show_bug.cgi?id=14076 The detailed problem analysis shows: Futex F is initialized with PTHREAD_PRIO_INHERIT and PTHREAD_MUTEX_ROBUST_NP attributes. T1 lock_futex_pi(F); T2 lock_futex_pi(F); --> T2 blocks on the futex and creates pi_state which is associated to T1. T1 exits --> exit_robust_list() runs --> Futex F userspace value TID field is set to 0 and FUTEX_OWNER_DIED bit is set. T3 lock_futex_pi(F); --> Succeeds due to the check for F's userspace TID field == 0 --> Claims ownership of the futex and sets its own TID into the userspace TID field of futex F --> returns to user space T1 --> exit_pi_state_list() --> Transfers pi_state to waiter T2 and wakes T2 via rt_mutex_unlock(&pi_state->mutex) T2 --> acquires pi_state->mutex and gains real ownership of the pi_state --> Claims ownership of the futex and sets its own TID into the userspace TID field of futex F --> returns to user space T3 --> observes inconsistent state This problem is independent of UP/SMP, preemptible/non preemptible kernels, or process shared vs. private. The only difference is that certain configurations are more likely to expose it. So as Siddhesh correctly analyzed the following check in futex_lock_pi_atomic() is the culprit: if (unlikely(ownerdied || !(curval & FUTEX_TID_MASK))) { We check the userspace value for a TID value of 0 and take over the futex unconditionally if that's true. AFAICT this check is there as it is correct for a different corner case of futexes: the WAITERS bit became stale. Now the proposed change - if (unlikely(ownerdied || !(curval & FUTEX_TID_MASK))) { + if (unlikely(ownerdied || + !(curval & (FUTEX_TID_MASK | FUTEX_WAITERS)))) { solves the problem, but it's not obvious why and it wreckages the "stale WAITERS bit" case. What happens is, that due to the WAITERS bit being set (T2 is blocked on that futex) it enforces T3 to go through lookup_pi_state(), which in the above case returns an existing pi_state and therefor forces T3 to legitimately fight with T2 over the ownership of the pi_state (via pi_state->mutex). Probelm solved! Though that does not work for the "WAITERS bit is stale" problem because if lookup_pi_state() does not find existing pi_state it returns -ERSCH (due to TID == 0) which causes futex_lock_pi() to return -ESRCH to user space because the OWNER_DIED bit is not set. Now there is a different solution to that problem. Do not look at the user space value at all and enforce a lookup of possibly available pi_state. If pi_state can be found, then the new incoming locker T3 blocks on that pi_state and legitimately races with T2 to acquire the rt_mutex and the pi_state and therefor the proper ownership of the user space futex. lookup_pi_state() has the correct order of checks. It first tries to find a pi_state associated with the user space futex and only if that fails it checks for futex TID value = 0. If no pi_state is available nothing can create new state at that point because this happens with the hash bucket lock held. So the above scenario changes to: T1 lock_futex_pi(F); T2 lock_futex_pi(F); --> T2 blocks on the futex and creates pi_state which is associated to T1. T1 exits --> exit_robust_list() runs --> Futex F userspace value TID field is set to 0 and FUTEX_OWNER_DIED bit is set. T3 lock_futex_pi(F); --> Finds pi_state and blocks on pi_state->rt_mutex T1 --> exit_pi_state_list() --> Transfers pi_state to waiter T2 and wakes it via rt_mutex_unlock(&pi_state->mutex) T2 --> acquires pi_state->mutex and gains ownership of the pi_state --> Claims ownership of the futex and sets its own TID into the userspace TID field of futex F --> returns to user space This covers all gazillion points on which T3 might come in between T1's exit_robust_list() clearing the TID field and T2 fixing it up. It also solves the "WAITERS bit stale" problem by forcing the take over. Another benefit of changing the code this way is that it makes it less dependent on untrusted user space values and therefor minimizes the possible wreckage which might be inflicted. As usual after staring for too long at the futex code my brain hurts so much that I really want to ditch that whole optimization of avoiding the syscall for the non contended case for PI futexes and rip out the maze of corner case handling code. Unfortunately we can't as user space relies on that existing behaviour, but at least thinking about it helps me to preserve my mental sanity. Maybe we should nevertheless :) Reported-and-tested-by: Siddhesh Poyarekar <[email protected]> Link: http://lkml.kernel.org/r/alpine.LFD.2.02.1210232138540.2756@ionos Acked-by: Darren Hart <[email protected]> Signed-off-by: Thomas Gleixner <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> drm/vmwgfx: Fix hibernation device reset commit 95e8f6a upstream. The device would not reset properly when resuming from hibernation. Signed-off-by: Thomas Hellstrom <[email protected]> Reviewed-by: Brian Paul <[email protected]> Reviewed-by: Dmitry Torokhov <[email protected]> Cc: [email protected] Signed-off-by: Dave Airlie <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> drm/i915: fixup infoframe support for sdvo commit 81014b9 upstream. At least the worst offenders: - SDVO specifies that the encoder should compute the ecc. Testing also shows that we must not send the ecc field, so copy the dip_infoframe struct to a temporay place and avoid the ecc field. This way the avi infoframe is exactly 17 bytes long, which agrees with what the spec mandates as a minimal storage capacity (with the ecc field it would be 18 bytes). - Only 17 when sending the avi infoframe. The SDVO spec explicitly says that sending more data than what the device announces results in undefined behaviour. - Add __attribute__((packed)) to the avi and spd infoframes, for otherwise they're wrongly aligned. Noticed because the avi infoframe ended up being 18 bytes large instead of 17. We haven't noticed this yet because we don't use the uint16_t fields yet (which are the only ones that would be wrongly aligned). This regression has been introduce by 3c17fe4 is the first bad commit commit 3c17fe4 Author: David Härdeman <[email protected]> Date: Fri Sep 24 21:44:32 2010 +0200 i915: enable AVI infoframe for intel_hdmi.c [v4] Patch tested on my g33 with a sdvo hdmi adaptor. Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=25732 Tested-by: Peter Ross <[email protected]> (G35 SDVO-HDMI) Reviewed-by: Eugeni Dodonov <[email protected]> Signed-Off-by: Daniel Vetter <[email protected]> Cc: Ben Hutchings <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> drm/i915: clear the entire sdvo infoframe buffer commit b6e0e54 upstream. Like in the case of native hdmi, which is fixed already in commit adf00b2 Author: Paulo Zanoni <[email protected]> Date: Tue Sep 25 13:23:34 2012 -0300 drm/i915: make sure we write all the DIP data bytes we need to clear the entire sdvo buffer to avoid upsetting the display. Since infoframe buffer writing is now a bit more elaborate, extract it into it's own function. This will be useful if we ever get around to properly update the ELD for sdvo. Also #define proper names for the two buffer indexes with fixed usage. v2: Cite the right commit above, spotted by Paulo Zanoni. v3: I'm too stupid to paste the right commit. v4: Ben Hutchings noticed that I've failed to handle an underflow in my loop logic, breaking it for i >= length + 8. Since I've just lost C programmer license, use his solution. Also, make the frustrated 0-base buffer size a notch more clear. Reported-and-tested-by: Jürg Billeter <[email protected]> Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=25732 Cc: Paulo Zanoni <[email protected]> Cc: Ben Hutchings <[email protected]> Reviewed-by: Rodrigo Vivi <[email protected]> Signed-off-by: Daniel Vetter <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> USB: mos7840: remove unused variable Fix warning about unused variable introduced by commit e681b66 ("USB: mos7840: remove invalid disconnect handling") upstream. A subsequent fix which removed the disconnect function got rid of the warning but that one was only backported to v3.6. Reported-by: Jiri Slaby <[email protected]> Signed-off-by: Johan Hovold <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> xfs: fix reading of wrapped log data commit 6ce377a upstream. Commit 4439647 ("xfs: reset buffer pointers before freeing them") in 3.0-rc1 introduced a regression when recovering log buffers that wrapped around the end of log. The second part of the log buffer at the start of the physical log was being read into the header buffer rather than the data buffer, and hence recovery was seeing garbage in the data buffer when it got to the region of the log buffer that was incorrectly read. Reported-by: Torsten Kaiser <[email protected]> Signed-off-by: Dave Chinner <[email protected]> Reviewed-by: Christoph Hellwig <[email protected]> Reviewed-by: Mark Tinguely <[email protected]> Signed-off-by: Ben Myers <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> intel-iommu: Fix AB-BA lockdep report commit 3e7abe2 upstream. When unbinding a device so that I could pass it through to a KVM VM, I got the lockdep report below. It looks like a legitimate lock ordering problem: - domain_context_mapping_one() takes iommu->lock and calls iommu_support_dev_iotlb(), which takes device_domain_lock (inside iommu->lock). - domain_remove_one_dev_info() starts by taking device_domain_lock then takes iommu->lock inside it (near the end of the function). So this is the classic AB-BA deadlock. It looks like a safe fix is to simply release device_domain_lock a bit earlier, since as far as I can tell, it doesn't protect any of the stuff accessed at the end of domain_remove_one_dev_info() anyway. BTW, the use of device_domain_lock looks a bit unsafe to me... it's at least not obvious to me why we aren't vulnerable to the race below: iommu_support_dev_iotlb() domain_remove_dev_info() lock device_domain_lock find info unlock device_domain_lock lock device_domain_lock find same info unlock device_domain_lock free_devinfo_mem(info) do stuff with info after it's free However I don't understand the locking here well enough to know if this is a real problem, let alone what the best fix is. Anyway here's the full lockdep output that prompted all of this: ======================================================= [ INFO: possible circular locking dependency detected ] 2.6.39.1+ Flemmard#1 ------------------------------------------------------- bash/13954 is trying to acquire lock: (&(&iommu->lock)->rlock){......}, at: [<ffffffff812f6421>] domain_remove_one_dev_info+0x121/0x230 but task is already holding lock: (device_domain_lock){-.-...}, at: [<ffffffff812f6508>] domain_remove_one_dev_info+0x208/0x230 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> Flemmard#1 (device_domain_lock){-.-...}: [<ffffffff8109ca9d>] lock_acquire+0x9d/0x130 [<ffffffff81571475>] _raw_spin_lock_irqsave+0x55/0xa0 [<ffffffff812f8350>] domain_context_mapping_one+0x600/0x750 [<ffffffff812f84df>] domain_context_mapping+0x3f/0x120 [<ffffffff812f9175>] iommu_prepare_identity_map+0x1c5/0x1e0 [<ffffffff81ccf1ca>] intel_iommu_init+0x88e/0xb5e [<ffffffff81cab204>] pci_iommu_init+0x16/0x41 [<ffffffff81002165>] do_one_initcall+0x45/0x190 [<ffffffff81ca3d3f>] kernel_init+0xe3/0x168 [<ffffffff8157ac24>] kernel_thread_helper+0x4/0x10 -> #0 (&(&iommu->lock)->rlock){......}: [<ffffffff8109bf3e>] __lock_acquire+0x195e/0x1e10 [<ffffffff8109ca9d>] lock_acquire+0x9d/0x130 [<ffffffff81571475>] _raw_spin_lock_irqsave+0x55/0xa0 [<ffffffff812f6421>] domain_remove_one_dev_info+0x121/0x230 [<ffffffff812f8b42>] device_notifier+0x72/0x90 [<ffffffff8157555c>] notifier_call_chain+0x8c/0xc0 [<ffffffff81089768>] __blocking_notifier_call_chain+0x78/0xb0 [<ffffffff810897b6>] blocking_notifier_call_chain+0x16/0x20 [<ffffffff81373a5c>] __device_release_driver+0xbc/0xe0 [<ffffffff81373ccf>] device_release_driver+0x2f/0x50 [<ffffffff81372ee3>] driver_unbind+0xa3/0xc0 [<ffffffff813724ac>] drv_attr_store+0x2c/0x30 [<ffffffff811e4506>] sysfs_write_file+0xe6/0x170 [<ffffffff8117569e>] vfs_write+0xce/0x190 [<ffffffff811759e4>] sys_write+0x54/0xa0 [<ffffffff81579a82>] system_call_fastpath+0x16/0x1b other info that might help us debug this: 6 locks held by bash/13954: #0: (&buffer->mutex){+.+.+.}, at: [<ffffffff811e4464>] sysfs_write_file+0x44/0x170 Flemmard#1: (s_active#3){++++.+}, at: [<ffffffff811e44ed>] sysfs_write_file+0xcd/0x170 Flemmard#2: (&__lockdep_no_validate__){+.+.+.}, at: [<ffffffff81372edb>] driver_unbind+0x9b/0xc0 Flemmard#3: (&__lockdep_no_validate__){+.+.+.}, at: [<ffffffff81373cc7>] device_release_driver+0x27/0x50 Flemmard#4: (&(&priv->bus_notifier)->rwsem){.+.+.+}, at: [<ffffffff8108974f>] __blocking_notifier_call_chain+0x5f/0xb0 Flemmard#5: (device_domain_lock){-.-...}, at: [<ffffffff812f6508>] domain_remove_one_dev_info+0x208/0x230 stack backtrace: Pid: 13954, comm: bash Not tainted 2.6.39.1+ Flemmard#1 Call Trace: [<ffffffff810993a7>] print_circular_bug+0xf7/0x100 [<ffffffff8109bf3e>] __lock_acquire+0x195e/0x1e10 [<ffffffff810972bd>] ? trace_hardirqs_off+0xd/0x10 [<ffffffff8109d57d>] ? trace_hardirqs_on_caller+0x13d/0x180 [<ffffffff8109ca9d>] lock_acquire+0x9d/0x130 [<ffffffff812f6421>] ? domain_remove_one_dev_info+0x121/0x230 [<ffffffff81571475>] _raw_spin_lock_irqsave+0x55/0xa0 [<ffffffff812f6421>] ? domain_remove_one_dev_info+0x121/0x230 [<ffffffff810972bd>] ? trace_hardirqs_off+0xd/0x10 [<ffffffff812f6421>] domain_remove_one_dev_info+0x121/0x230 [<ffffffff812f8b42>] device_notifier+0x72/0x90 [<ffffffff8157555c>] notifier_call_chain+0x8c/0xc0 [<ffffffff81089768>] __blocking_notifier_call_chain+0x78/0xb0 [<ffffffff810897b6>] blocking_notifier_call_chain+0x16/0x20 [<ffffffff81373a5c>] __device_release_driver+0xbc/0xe0 [<ffffffff81373ccf>] device_release_driver+0x2f/0x50 [<ffffffff81372ee3>] driver_unbind+0xa3/0xc0 [<ffffffff813724ac>] drv_attr_store+0x2c/0x30 [<ffffffff811e4506>] sysfs_write_file+0xe6/0x170 [<ffffffff8117569e>] vfs_write+0xce/0x190 [<ffffffff811759e4>] sys_write+0x54/0xa0 [<ffffffff81579a82>] system_call_fastpath+0x16/0x1b Signed-off-by: Roland Dreier <[email protected]> Signed-off-by: David Woodhouse <[email protected]> Cc: Steven Rostedt <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> ALSA: Fix card refcount unbalance commit 8bb4d9c upstream. There are uncovered cases whether the card refcount introduced by the commit a0830db isn't properly increased or decreased: - OSS PCM and mixer success paths - When lookup function gets NULL This patch fixes these places. Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=50251 Signed-off-by: Takashi Iwai <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> ALSA: usb-audio: Fix mutex deadlock at disconnection commit 10e4423 upstream. The recent change for USB-audio disconnection race fixes introduced a mutex deadlock again. There is a circular dependency between chip->shutdown_rwsem and pcm->open_mutex, depicted like below, when a device is opened during the disconnection operation: A. snd_usb_audio_disconnect() -> card.c::register_mutex -> chip->shutdown_rwsem (write) -> snd_card_disconnect() -> pcm.c::register_mutex -> pcm->open_mutex B. snd_pcm_open() -> pcm->open_mutex -> snd_usb_pcm_open() -> chip->shutdown_rwsem (read) Since the chip->shutdown_rwsem protection in the case A is required only for turning on the chip->shutdown flag and it doesn't have to be taken for the whole operation, we can reduce its window in snd_usb_audio_disconnect(). Reported-by: Jiri Slaby <[email protected]> Signed-off-by: Takashi Iwai <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
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