1. 29 Jan, 2016 7 commits
  2. 28 Jan, 2016 33 commits
    • Josh Boyer's avatar
      ideapad-laptop: Add Lenovo Yoga 700 to no_hw_rfkill dmi list · e90344af
      Josh Boyer authored
      commit 6b31de3e upstream.
      
      Like the Yoga 900 models the Lenovo Yoga 700 does not have a
      hw rfkill switch, and trying to read the hw rfkill switch through the
      ideapad module causes it to always reported blocking breaking wifi.
      
      This commit adds the Lenovo Yoga 700 to the no_hw_rfkill dmi list, fixing
      the wifi breakage.
      
      BugLink: https://bugzilla.redhat.com/show_bug.cgi?id=1295272
      Tested-by: <dinyar.rabady+spam@gmail.com>
      Signed-off-by: default avatarJosh Boyer <jwboyer@fedoraproject.org>
      Signed-off-by: default avatarDarren Hart <dvhart@linux.intel.com>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      e90344af
    • Rich Felker's avatar
      b3d6f289
    • Tariq Saeed's avatar
      ocfs2: NFS hangs in __ocfs2_cluster_lock due to race with ocfs2_unblock_lock · 87f4697b
      Tariq Saeed authored
      commit b1b1e15e upstream.
      
      NFS on a 2 node ocfs2 cluster each node exporting dir.  The lock causing
      the hang is the global bit map inode lock.  Node 1 is master, has the
      lock granted in PR mode; Node 2 is in the converting list (PR -> EX).
      There are no holders of the lock on the master node so it should
      downconvert to NL and grant EX to node 2 but that does not happen.
      BLOCKED + QUEUED in lock res are set and it is on osb blocked list.
      Threads are waiting in __ocfs2_cluster_lock on BLOCKED.  One thread
      wants EX, rest want PR.  So it is as though the downconvert thread needs
      to be kicked to complete the conv.
      
      The hang is caused by an EX req coming into __ocfs2_cluster_lock on the
      heels of a PR req after it sets BUSY (drops l_lock, releasing EX
      thread), forcing the incoming EX to wait on BUSY without doing anything.
      PR has called ocfs2_dlm_lock, which sets the node 1 lock from NL -> PR,
      queues ast.
      
      At this time, upconvert (PR ->EX) arrives from node 2, finds conflict
      with node 1 lock in PR, so the lock res is put on dlm thread's dirty
      listt.
      
      After ret from ocf2_dlm_lock, PR thread now waits behind EX on BUSY till
      awoken by ast.
      
      Now it is dlm_thread that serially runs dlm_shuffle_lists, ast, bast, in
      that order.  dlm_shuffle_lists ques a bast on behalf of node 2 (which
      will be run by dlm_thread right after the ast).  ast does its part, sets
      UPCONVERT_FINISHING, clears BUSY and wakes its waiters.  Next,
      dlm_thread runs bast.  It sets BLOCKED and kicks dc thread.  dc thread
      runs ocfs2_unblock_lock, but since UPCONVERT_FINISHING set, skips doing
      anything and reques.
      
      Inside of __ocfs2_cluster_lock, since EX has been waiting on BUSY ahead
      of PR, it wakes up first, finds BLOCKED set and skips doing anything but
      clearing UPCONVERT_FINISHING (which was actually "meant" for the PR
      thread), and this time waits on BLOCKED.  Next, the PR thread comes out
      of wait but since UPCONVERT_FINISHING is not set, it skips updating the
      l_ro_holders and goes straight to wait on BLOCKED.  So there, we have a
      hang! Threads in __ocfs2_cluster_lock wait on BLOCKED, lock res in osb
      blocked list.  Only when dc thread is awoken, it will run
      ocfs2_unblock_lock and things will unhang.
      
      One way to fix this is to wake the dc thread on the flag after clearing
      UPCONVERT_FINISHING
      
      Orabug: 20933419
      Signed-off-by: default avatarTariq Saeed <tariq.x.saeed@oracle.com>
      Signed-off-by: default avatarSantosh Shilimkar <santosh.shilimkar@oracle.com>
      Reviewed-by: default avatarWengang Wang <wen.gang.wang@oracle.com>
      Reviewed-by: default avatarMark Fasheh <mfasheh@suse.de>
      Cc: Joel Becker <jlbec@evilplan.org>
      Cc: Junxiao Bi <junxiao.bi@oracle.com>
      Reviewed-by: default avatarJoseph Qi <joseph.qi@huawei.com>
      Cc: Eric Ren <zren@suse.com>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      87f4697b
    • Takashi Iwai's avatar
      ALSA: timer: Handle disconnection more safely · d758ee58
      Takashi Iwai authored
      commit 230323da upstream.
      
      Currently ALSA timer device doesn't take the disconnection into
      account very well; it merely unlinks the timer device at disconnection
      callback but does nothing else.  Because of this, when an application
      accessing the timer device is disconnected, it may release the
      resource before actually closed.  In most cases, it results in a
      warning message indicating a leftover timer instance like:
         ALSA: timer xxxx is busy?
      But basically this is an open race.
      
      This patch tries to address it.  The strategy is like other ALSA
      devices: namely,
      - Manage card's refcount at each open/close
      - Wake up the pending tasks at disconnection
      - Check the shutdown flag appropriately at each possible call
      
      Note that this patch has one ugly hack to handle the wakeup of pending
      tasks.  It'd be cleaner to introduce a new disconnect op to
      snd_timer_instance ops.  But since it would lead to internal ABI
      breakage and it eventually increase my own work when backporting to
      stable kernels, I took a different path to implement locally in
      timer.c.  A cleanup patch will follow at next for 4.5 kernel.
      
      Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=109431Signed-off-by: default avatarTakashi Iwai <tiwai@suse.de>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      d758ee58
    • Takashi Iwai's avatar
      ALSA: hda - Flush the pending probe work at remove · 0a1d2dc5
      Takashi Iwai authored
      commit 991f86d7 upstream.
      
      As HD-audio driver does deferred probe internally via workqueue, the
      driver might go into the mixed state doing both probe and remove when
      the module gets unloaded during the probe work.  This eventually
      triggers an Oops, unsurprisingly.
      
      For avoiding this race, we just need to flush the pending probe work
      explicitly before actually starting the resource release.
      
      Bugzilla: https://bugzilla.opensuse.org/show_bug.cgi?id=960710Signed-off-by: default avatarTakashi Iwai <tiwai@suse.de>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      0a1d2dc5
    • Nicholas Bellinger's avatar
      iscsi-target: Fix potential dead-lock during node acl delete · 1c035f6b
      Nicholas Bellinger authored
      commit 26a99c19 upstream.
      
      This patch is a iscsi-target specific bug-fix for a dead-lock
      that can occur during explicit struct se_node_acl->acl_group
      se_session deletion via configfs rmdir(2), when iscsi-target
      time2retain timer is still active.
      
      It changes iscsi-target to obtain se_portal_group->session_lock
      internally using spin_in_locked() to check for the specific
      se_node_acl configfs shutdown rmdir(2) case.
      
      Note this patch is intended for stable, and the subsequent
      v4.5-rc patch converts target_core_tpg.c to use proper
      se_sess->sess_kref reference counting for both se_node_acl
      deletion + se_node_acl->queue_depth se_session restart.
      Reported-by: default avatar: Sagi Grimberg <sagig@mellanox.com>
      Cc: Christoph Hellwig <hch@lst.de>
      Cc: Hannes Reinecke <hare@suse.de>
      Cc: Andy Grover <agrover@redhat.com>
      Cc: Mike Christie <michaelc@cs.wisc.edu>
      Signed-off-by: default avatarNicholas Bellinger <nab@linux-iscsi.org>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      1c035f6b
    • Josh Boyer's avatar
      ideapad-laptop: Add Lenovo ideapad Y700-17ISK to no_hw_rfkill dmi list · ae82f303
      Josh Boyer authored
      commit edde316a upstream.
      
      One of the newest ideapad models also lacks a physical hw rfkill switch,
      and trying to read the hw rfkill switch through the ideapad module
      causes it to always reported blocking breaking wifi.
      
      Fix it by adding this model to the DMI list.
      
      BugLink: https://bugzilla.redhat.com/show_bug.cgi?id=1286293Signed-off-by: default avatarJosh Boyer <jwboyer@fedoraproject.org>
      Signed-off-by: default avatarDarren Hart <dvhart@linux.intel.com>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      ae82f303
    • Vinit Agnihotri's avatar
      IB/qib: Support creating qps with GFP_NOIO flag · 5e1cc3a2
      Vinit Agnihotri authored
      commit fbbeb863 upstream.
      
      The current code is problematic when the QP creation and ipoib is used to
      support NFS and NFS desires to do IO for paging purposes. In that case, the
      GFP_KERNEL allocation in qib_qp.c causes a deadlock in tight memory
      situations.
      
      This fix adds support to create queue pair with GFP_NOIO flag for connected
      mode only to cleanly fail the create queue pair in those situations.
      Reviewed-by: default avatarMike Marciniszyn <mike.marciniszyn@intel.com>
      Signed-off-by: default avatarVinit Agnihotri <vinit.abhay.agnihotri@intel.com>
      Signed-off-by: default avatarDoug Ledford <dledford@redhat.com>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      5e1cc3a2
    • Mike Marciniszyn's avatar
      IB/qib: fix mcast detach when qp not attached · b2a2d140
      Mike Marciniszyn authored
      commit 09dc9cd6 upstream.
      
      The code produces the following trace:
      
      [1750924.419007] general protection fault: 0000 [#3] SMP
      [1750924.420364] Modules linked in: nfnetlink autofs4 rpcsec_gss_krb5 nfsv4
      dcdbas rfcomm bnep bluetooth nfsd auth_rpcgss nfs_acl dm_multipath nfs lockd
      scsi_dh sunrpc fscache radeon ttm drm_kms_helper drm serio_raw parport_pc
      ppdev i2c_algo_bit lpc_ich ipmi_si ib_mthca ib_qib dca lp parport ib_ipoib
      mac_hid ib_cm i3000_edac ib_sa ib_uverbs edac_core ib_umad ib_mad ib_core
      ib_addr tg3 ptp dm_mirror dm_region_hash dm_log psmouse pps_core
      [1750924.420364] CPU: 1 PID: 8401 Comm: python Tainted: G D
      3.13.0-39-generic #66-Ubuntu
      [1750924.420364] Hardware name: Dell Computer Corporation PowerEdge
      860/0XM089, BIOS A04 07/24/2007
      [1750924.420364] task: ffff8800366a9800 ti: ffff88007af1c000 task.ti:
      ffff88007af1c000
      [1750924.420364] RIP: 0010:[<ffffffffa0131d51>] [<ffffffffa0131d51>]
      qib_mcast_qp_free+0x11/0x50 [ib_qib]
      [1750924.420364] RSP: 0018:ffff88007af1dd70  EFLAGS: 00010246
      [1750924.420364] RAX: 0000000000000001 RBX: ffff88007b822688 RCX:
      000000000000000f
      [1750924.420364] RDX: ffff88007b822688 RSI: ffff8800366c15a0 RDI:
      6764697200000000
      [1750924.420364] RBP: ffff88007af1dd78 R08: 0000000000000001 R09:
      0000000000000000
      [1750924.420364] R10: 0000000000000011 R11: 0000000000000246 R12:
      ffff88007baa1d98
      [1750924.420364] R13: ffff88003ecab000 R14: ffff88007b822660 R15:
      0000000000000000
      [1750924.420364] FS:  00007ffff7fd8740(0000) GS:ffff88007fc80000(0000)
      knlGS:0000000000000000
      [1750924.420364] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
      [1750924.420364] CR2: 00007ffff597c750 CR3: 000000006860b000 CR4:
      00000000000007e0
      [1750924.420364] Stack:
      [1750924.420364]  ffff88007b822688 ffff88007af1ddf0 ffffffffa0132429
      000000007af1de20
      [1750924.420364]  ffff88007baa1dc8 ffff88007baa0000 ffff88007af1de70
      ffffffffa00cb313
      [1750924.420364]  00007fffffffde88 0000000000000000 0000000000000008
      ffff88003ecab000
      [1750924.420364] Call Trace:
      [1750924.420364]  [<ffffffffa0132429>] qib_multicast_detach+0x1e9/0x350
      [ib_qib]
      [1750924.568035]  [<ffffffffa00cb313>] ? ib_uverbs_modify_qp+0x323/0x3d0
      [ib_uverbs]
      [1750924.568035]  [<ffffffffa0092d61>] ib_detach_mcast+0x31/0x50 [ib_core]
      [1750924.568035]  [<ffffffffa00cc213>] ib_uverbs_detach_mcast+0x93/0x170
      [ib_uverbs]
      [1750924.568035]  [<ffffffffa00c61f6>] ib_uverbs_write+0xc6/0x2c0 [ib_uverbs]
      [1750924.568035]  [<ffffffff81312e68>] ? apparmor_file_permission+0x18/0x20
      [1750924.568035]  [<ffffffff812d4cd3>] ? security_file_permission+0x23/0xa0
      [1750924.568035]  [<ffffffff811bd214>] vfs_write+0xb4/0x1f0
      [1750924.568035]  [<ffffffff811bdc49>] SyS_write+0x49/0xa0
      [1750924.568035]  [<ffffffff8172f7ed>] system_call_fastpath+0x1a/0x1f
      [1750924.568035] Code: 66 2e 0f 1f 84 00 00 00 00 00 31 c0 5d c3 66 2e 0f 1f
      84 00 00 00 00 00 66 90 0f 1f 44 00 00 55 48 89 e5 53 48 89 fb 48 8b 7f 10
      <f0> ff 8f 40 01 00 00 74 0e 48 89 df e8 8e f8 06 e1 5b 5d c3 0f
      [1750924.568035] RIP  [<ffffffffa0131d51>] qib_mcast_qp_free+0x11/0x50
      [ib_qib]
      [1750924.568035]  RSP <ffff88007af1dd70>
      [1750924.650439] ---[ end trace 73d5d4b3f8ad4851 ]
      
      The fix is to note the qib_mcast_qp that was found.   If none is found, then
      return EINVAL indicating the error.
      Reviewed-by: default avatarDennis Dalessandro <dennis.dalessandro@intel.com>
      Reported-by: default avatarJason Gunthorpe <jgunthorpe@obsidianresearch.com>
      Signed-off-by: default avatarMike Marciniszyn <mike.marciniszyn@intel.com>
      Signed-off-by: default avatarDoug Ledford <dledford@redhat.com>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      b2a2d140
    • Jean Delvare's avatar
      crypto: crc32c - Fix crc32c soft dependency · 80529662
      Jean Delvare authored
      commit fd7f6727 upstream.
      
      I don't think it makes sense for a module to have a soft dependency
      on itself. This seems quite cyclic by nature and I can't see what
      purpose it could serve.
      
      OTOH libcrc32c calls crypto_alloc_shash("crc32c", 0, 0) so it pretty
      much assumes that some incarnation of the "crc32c" hash algorithm has
      been loaded. Therefore it makes sense to have the soft dependency
      there (as crc-t10dif does.)
      
      Cc: Tim Chen <tim.c.chen@linux.intel.com>
      Cc: "David S. Miller" <davem@davemloft.net>
      Signed-off-by: default avatarJean Delvare <jdelvare@suse.de>
      Signed-off-by: default avatarHerbert Xu <herbert@gondor.apana.org.au>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      80529662
    • Herbert Xu's avatar
      crypto: algif_skcipher - Load TX SG list after waiting · 78b0a019
      Herbert Xu authored
      commit 4f0414e5 upstream.
      
      We need to load the TX SG list in sendmsg(2) after waiting for
      incoming data, not before.
      Reported-by: default avatarDmitry Vyukov <dvyukov@google.com>
      Signed-off-by: default avatarHerbert Xu <herbert@gondor.apana.org.au>
      Tested-by: default avatarDmitry Vyukov <dvyukov@google.com>
      [ kamal: backport to 3.19-stable: context ]
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      78b0a019
    • Dave Chinner's avatar
      xfs: log mount failures don't wait for buffers to be released · 51006a38
      Dave Chinner authored
      commit 85bec546 upstream.
      
      Recently I've been seeing xfs/051 fail on 1k block size filesystems.
      Trying to trace the events during the test lead to the problem going
      away, indicating that it was a race condition that lead to this
      ASSERT failure:
      
      XFS: Assertion failed: atomic_read(&pag->pag_ref) == 0, file: fs/xfs/xfs_mount.c, line: 156
      .....
      [<ffffffff814e1257>] xfs_free_perag+0x87/0xb0
      [<ffffffff814e21b9>] xfs_mountfs+0x4d9/0x900
      [<ffffffff814e5dff>] xfs_fs_fill_super+0x3bf/0x4d0
      [<ffffffff811d8800>] mount_bdev+0x180/0x1b0
      [<ffffffff814e3ff5>] xfs_fs_mount+0x15/0x20
      [<ffffffff811d90a8>] mount_fs+0x38/0x170
      [<ffffffff811f4347>] vfs_kern_mount+0x67/0x120
      [<ffffffff811f7018>] do_mount+0x218/0xd60
      [<ffffffff811f7e5b>] SyS_mount+0x8b/0xd0
      
      When I finally caught it with tracing enabled, I saw that AG 2 had
      an elevated reference count and a buffer was responsible for it. I
      tracked down the specific buffer, and found that it was missing the
      final reference count release that would put it back on the LRU and
      hence be found by xfs_wait_buftarg() calls in the log mount failure
      handling.
      
      The last four traces for the buffer before the assert were (trimmed
      for relevance)
      
      kworker/0:1-5259   xfs_buf_iodone:        hold 2  lock 0 flags ASYNC
      kworker/0:1-5259   xfs_buf_ioerror:       hold 2  lock 0 error -5
      mount-7163	   xfs_buf_lock_done:     hold 2  lock 0 flags ASYNC
      mount-7163	   xfs_buf_unlock:        hold 2  lock 1 flags ASYNC
      
      This is an async write that is completing, so there's nobody waiting
      for it directly.  Hence we call xfs_buf_relse() once all the
      processing is complete. That does:
      
      static inline void xfs_buf_relse(xfs_buf_t *bp)
      {
      	xfs_buf_unlock(bp);
      	xfs_buf_rele(bp);
      }
      
      Now, it's clear that mount is waiting on the buffer lock, and that
      it has been released by xfs_buf_relse() and gained by mount. This is
      expected, because at this point the mount process is in
      xfs_buf_delwri_submit() waiting for all the IO it submitted to
      complete.
      
      The mount process, however, is waiting on the lock for the buffer
      because it is in xfs_buf_delwri_submit(). This waits for IO
      completion, but it doesn't wait for the buffer reference owned by
      the IO to go away. The mount process collects all the completions,
      fails the log recovery, and the higher level code then calls
      xfs_wait_buftarg() to free all the remaining buffers in the
      filesystem.
      
      The issue is that on unlocking the buffer, the scheduler has decided
      that the mount process has higher priority than the the kworker
      thread that is running the IO completion, and so immediately
      switched contexts to the mount process from the semaphore unlock
      code, hence preventing the kworker thread from finishing the IO
      completion and releasing the IO reference to the buffer.
      
      Hence by the time that xfs_wait_buftarg() is run, the buffer still
      has an active reference and so isn't on the LRU list that the
      function walks to free the remaining buffers. Hence we miss that
      buffer and continue onwards to tear down the mount structures,
      at which time we get find a stray reference count on the perag
      structure. On a non-debug kernel, this will be ignored and the
      structure torn down and freed. Hence when the kworker thread is then
      rescheduled and the buffer released and freed, it will access a
      freed perag structure.
      
      The problem here is that when the log mount fails, we still need to
      quiesce the log to ensure that the IO workqueues have returned to
      idle before we run xfs_wait_buftarg(). By synchronising the
      workqueues, we ensure that all IO completions are fully processed,
      not just to the point where buffers have been unlocked. This ensures
      we don't end up in the situation above.
      Signed-off-by: default avatarDave Chinner <dchinner@redhat.com>
      Reviewed-by: default avatarBrian Foster <bfoster@redhat.com>
      Signed-off-by: default avatarDave Chinner <david@fromorbit.com>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      51006a38
    • Arnd Bergmann's avatar
      ARM: debug-ll: fix BCM63xx entry for multiplatform · 1dda19b4
      Arnd Bergmann authored
      commit 6c548099 upstream.
      
      During my randconfig build testing, I found that a kernel with
      DEBUG_AT91_UART and ARCH_BCM_63XX fails to build:
      
      arch/arm/include/debug/at91.S:18:0: error: "CONFIG_DEBUG_UART_VIRT" redefined [-Werror]
      
      It turns out that the DEBUG_UART_BCM63XX option is enabled whenever
      the ARCH_BCM_63XX is, and that breaks multiplatform kernels because
      we then end up using the UART address from BCM63XX rather than the
      one we actually configured (if any).
      
      This changes the BCM63XX options to only have one Kconfig option,
      and only enable that if the user explicitly turns it on.
      Signed-off-by: default avatarArnd Bergmann <arnd@arndb.de>
      Fixes: b51312be ("ARM: BCM63XX: add low-level UART debug support")
      [ kamal: backport to 3.19-stable: context ]
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      1dda19b4
    • Takashi Iwai's avatar
      ALSA: control: Avoid kernel warnings from tlv ioctl with numid 0 · 77e05fba
      Takashi Iwai authored
      commit c0bcdbdf upstream.
      
      When a TLV ioctl with numid zero is handled, the driver may spew a
      kernel warning with a stack trace at each call.  The check was
      intended obviously only for a kernel driver, but not for a user
      interaction.  Let's fix it.
      
      This was spotted by syzkaller fuzzer.
      Reported-by: default avatarDmitry Vyukov <dvyukov@google.com>
      Signed-off-by: default avatarTakashi Iwai <tiwai@suse.de>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      77e05fba
    • Nicolas Boichat's avatar
      ALSA: seq: Fix snd_seq_call_port_info_ioctl in compat mode · 9f148300
      Nicolas Boichat authored
      commit 9586495d upstream.
      
      This reverts one hunk of
      commit ef44a1ec ("ALSA: sound/core: use memdup_user()"), which
      replaced a number of kmalloc followed by memcpy with memdup calls.
      
      In this case, we are copying from a struct snd_seq_port_info32 to a
      struct snd_seq_port_info, but the latter is 4 bytes longer than the
      32-bit version, so we need to separate kmalloc and copy calls.
      
      Fixes: ef44a1ec ('ALSA: sound/core: use memdup_user()')
      Signed-off-by: default avatarNicolas Boichat <drinkcat@chromium.org>
      Signed-off-by: default avatarTakashi Iwai <tiwai@suse.de>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      9f148300
    • Nicolas Boichat's avatar
      ALSA: pcm: Fix snd_pcm_hw_params struct copy in compat mode · c8be7897
      Nicolas Boichat authored
      commit 43c54b8c upstream.
      
      This reverts one hunk of
      commit ef44a1ec ("ALSA: sound/core: use memdup_user()"), which
      replaced a number of kmalloc followed by memcpy with memdup calls.
      
      In this case, we are copying from a struct snd_pcm_hw_params32 to
      a struct snd_pcm_hw_params, but the latter is 4 bytes longer than
      the 32-bit version, so we need to separate kmalloc and copy calls.
      
      This actually leads to an out-of-bounds memory access later on
      in sound/soc/soc-pcm.c:soc_pcm_hw_params() (detected using KASan).
      
      Fixes: ef44a1ec ('ALSA: sound/core: use memdup_user()')
      Signed-off-by: default avatarNicolas Boichat <drinkcat@chromium.org>
      Signed-off-by: default avatarTakashi Iwai <tiwai@suse.de>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      c8be7897
    • Takashi Iwai's avatar
      ALSA: hrtimer: Fix stall by hrtimer_cancel() · 3811f772
      Takashi Iwai authored
      commit 2ba1fe7a upstream.
      
      hrtimer_cancel() waits for the completion from the callback, thus it
      must not be called inside the callback itself.  This was already a
      problem in the past with ALSA hrtimer driver, and the early commit
      [fcfdebe7: ALSA: hrtimer - Fix lock-up] tried to address it.
      
      However, the previous fix is still insufficient: it may still cause a
      lockup when the ALSA timer instance reprograms itself in its callback.
      Then it invokes the start function even in snd_timer_interrupt() that
      is called in hrtimer callback itself, results in a CPU stall.  This is
      no hypothetical problem but actually triggered by syzkaller fuzzer.
      
      This patch tries to fix the issue again.  Now we call
      hrtimer_try_to_cancel() at both start and stop functions so that it
      won't fall into a deadlock, yet giving some chance to cancel the queue
      if the functions have been called outside the callback.  The proper
      hrtimer_cancel() is called in anyway at closing, so this should be
      enough.
      Reported-and-tested-by: default avatarDmitry Vyukov <dvyukov@google.com>
      Signed-off-by: default avatarTakashi Iwai <tiwai@suse.de>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      3811f772
    • Herbert Xu's avatar
      crypto: af_alg - Forbid bind(2) when nokey child sockets are present · 1cc38158
      Herbert Xu authored
      commit a6a48c56 upstream.
      
      This patch forbids the calling of bind(2) when there are child
      sockets created by accept(2) in existence, even if they are created
      on the nokey path.
      
      This is needed as those child sockets have references to the tfm
      object which bind(2) will destroy.
      Signed-off-by: default avatarHerbert Xu <herbert@gondor.apana.org.au>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      1cc38158
    • Herbert Xu's avatar
      crypto: af_alg - Allow af_af_alg_release_parent to be called on nokey path · 074bd2ed
      Herbert Xu authored
      commit 6a935170 upstream.
      
      This patch allows af_alg_release_parent to be called even for
      nokey sockets.
      Signed-off-by: default avatarHerbert Xu <herbert@gondor.apana.org.au>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      074bd2ed
    • Herbert Xu's avatar
      crypto: hash - Add crypto_ahash_has_setkey · bfde8726
      Herbert Xu authored
      commit a5596d63 upstream.
      
      This patch adds a way for ahash users to determine whether a key
      is required by a crypto_ahash transform.
      Signed-off-by: default avatarHerbert Xu <herbert@gondor.apana.org.au>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      bfde8726
    • Herbert Xu's avatar
      crypto: af_alg - Add nokey compatibility path · 3baec392
      Herbert Xu authored
      commit 37766586 upstream.
      
      This patch adds a compatibility path to support old applications
      that do acept(2) before setkey.
      Signed-off-by: default avatarHerbert Xu <herbert@gondor.apana.org.au>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      3baec392
    • Herbert Xu's avatar
      crypto: af_alg - Fix socket double-free when accept fails · b37fa326
      Herbert Xu authored
      commit a383292c upstream.
      
      When we fail an accept(2) call we will end up freeing the socket
      twice, once due to the direct sk_free call and once again through
      newsock.
      
      This patch fixes this by removing the sk_free call.
      Reported-by: default avatarDmitry Vyukov <dvyukov@google.com>
      Signed-off-by: default avatarHerbert Xu <herbert@gondor.apana.org.au>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      b37fa326
    • Herbert Xu's avatar
      crypto: af_alg - Disallow bind/setkey/... after accept(2) · 5a88170a
      Herbert Xu authored
      commit c840ac6a upstream.
      
      Each af_alg parent socket obtained by socket(2) corresponds to a
      tfm object once bind(2) has succeeded.  An accept(2) call on that
      parent socket creates a context which then uses the tfm object.
      
      Therefore as long as any child sockets created by accept(2) exist
      the parent socket must not be modified or freed.
      
      This patch guarantees this by using locks and a reference count
      on the parent socket.  Any attempt to modify the parent socket will
      fail with EBUSY.
      Reported-by: default avatarDmitry Vyukov <dvyukov@google.com>
      Signed-off-by: default avatarHerbert Xu <herbert@gondor.apana.org.au>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      5a88170a
    • Takashi Iwai's avatar
      ALSA: hda - Fix bass pin fixup for ASUS N550JX · 2c0ad25f
      Takashi Iwai authored
      commit db8948e6 upstream.
      
      ASUS N550JX (PCI SSID 1043:13df) requires the same fixup for a bass
      speaker output pin as other N550 models.
      
      Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=110001Signed-off-by: default avatarTakashi Iwai <tiwai@suse.de>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      2c0ad25f
    • Tejun Heo's avatar
      printk: do cond_resched() between lines while outputting to consoles · fbddd214
      Tejun Heo authored
      commit 8d91f8b1 upstream.
      
      @console_may_schedule tracks whether console_sem was acquired through
      lock or trylock.  If the former, we're inside a sleepable context and
      console_conditional_schedule() performs cond_resched().  This allows
      console drivers which use console_lock for synchronization to yield
      while performing time-consuming operations such as scrolling.
      
      However, the actual console outputting is performed while holding
      irq-safe logbuf_lock, so console_unlock() clears @console_may_schedule
      before starting outputting lines.  Also, only a few drivers call
      console_conditional_schedule() to begin with.  This means that when a
      lot of lines need to be output by console_unlock(), for example on a
      console registration, the task doing console_unlock() may not yield for
      a long time on a non-preemptible kernel.
      
      If this happens with a slow console devices, for example a serial
      console, the outputting task may occupy the cpu for a very long time.
      Long enough to trigger softlockup and/or RCU stall warnings, which in
      turn pile more messages, sometimes enough to trigger the next cycle of
      warnings incapacitating the system.
      
      Fix it by making console_unlock() insert cond_resched() between lines if
      @console_may_schedule.
      Signed-off-by: default avatarTejun Heo <tj@kernel.org>
      Reported-by: default avatarCalvin Owens <calvinowens@fb.com>
      Acked-by: default avatarJan Kara <jack@suse.com>
      Cc: Dave Jones <davej@codemonkey.org.uk>
      Cc: Kyle McMartin <kyle@kernel.org>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      fbddd214
    • Vitaly Kuznetsov's avatar
      kernel/panic.c: turn off locks debug before releasing console lock · 64b37cda
      Vitaly Kuznetsov authored
      commit 7625b3a0 upstream.
      
      Commit 08d78658 ("panic: release stale console lock to always get the
      logbuf printed out") introduced an unwanted bad unlock balance report when
      panic() is called directly and not from OOPS (e.g.  from out_of_memory()).
      The difference is that in case of OOPS we disable locks debug in
      oops_enter() and on direct panic call nobody does that.
      
      Fixes: 08d78658 ("panic: release stale console lock to always get the logbuf printed out")
      Reported-by: default avatarkernel test robot <ying.huang@linux.intel.com>
      Signed-off-by: default avatarVitaly Kuznetsov <vkuznets@redhat.com>
      Cc: HATAYAMA Daisuke <d.hatayama@jp.fujitsu.com>
      Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
      Cc: Jiri Kosina <jkosina@suse.cz>
      Cc: Baoquan He <bhe@redhat.com>
      Cc: Prarit Bhargava <prarit@redhat.com>
      Cc: Xie XiuQi <xiexiuqi@huawei.com>
      Cc: Seth Jennings <sjenning@redhat.com>
      Cc: "K. Y. Srinivasan" <kys@microsoft.com>
      Cc: Jan Kara <jack@suse.cz>
      Cc: Petr Mladek <pmladek@suse.cz>
      Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      64b37cda
    • Vitaly Kuznetsov's avatar
      panic: release stale console lock to always get the logbuf printed out · ae3176f0
      Vitaly Kuznetsov authored
      commit 08d78658 upstream.
      
      In some cases we may end up killing the CPU holding the console lock
      while still having valuable data in logbuf. E.g. I'm observing the
      following:
      
      - A crash is happening on one CPU and console_unlock() is being called on
        some other.
      
      - console_unlock() tries to print out the buffer before releasing the lock
        and on slow console it takes time.
      
      - in the meanwhile crashing CPU does lots of printk()-s with valuable data
        (which go to the logbuf) and sends IPIs to all other CPUs.
      
      - console_unlock() finishes printing previous chunk and enables interrupts
        before trying to print out the rest, the CPU catches the IPI and never
        releases console lock.
      
      This is not the only possible case: in VT/fb subsystems we have many other
      console_lock()/console_unlock() users.  Non-masked interrupts (or
      receiving NMI in case of extreme slowness) will have the same result.
      Getting the whole console buffer printed out on crash should be top
      priority.
      
      [akpm@linux-foundation.org: tweak comment text]
      Signed-off-by: default avatarVitaly Kuznetsov <vkuznets@redhat.com>
      Cc: HATAYAMA Daisuke <d.hatayama@jp.fujitsu.com>
      Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
      Cc: Jiri Kosina <jkosina@suse.cz>
      Cc: Baoquan He <bhe@redhat.com>
      Cc: Prarit Bhargava <prarit@redhat.com>
      Cc: Xie XiuQi <xiexiuqi@huawei.com>
      Cc: Seth Jennings <sjenning@redhat.com>
      Cc: "K. Y. Srinivasan" <kys@microsoft.com>
      Cc: Jan Kara <jack@suse.cz>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      ae3176f0
    • Martijn Coenen's avatar
      memcg: only free spare array when readers are done · 7d454f3e
      Martijn Coenen authored
      commit 6611d8d7 upstream.
      
      A spare array holding mem cgroup threshold events is kept around to make
      sure we can always safely deregister an event and have an array to store
      the new set of events in.
      
      In the scenario where we're going from 1 to 0 registered events, the
      pointer to the primary array containing 1 event is copied to the spare
      slot, and then the spare slot is freed because no events are left.
      However, it is freed before calling synchronize_rcu(), which means
      readers may still be accessing threshold->primary after it is freed.
      
      Fixed by only freeing after synchronize_rcu().
      Signed-off-by: default avatarMartijn Coenen <maco@google.com>
      Cc: Johannes Weiner <hannes@cmpxchg.org>
      Acked-by: default avatarMichal Hocko <mhocko@suse.com>
      Cc: Vladimir Davydov <vdavydov@virtuozzo.com>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      7d454f3e
    • Naoya Horiguchi's avatar
      mm: soft-offline: check return value in second __get_any_page() call · a76ce1fb
      Naoya Horiguchi authored
      commit d96b339f upstream.
      
      I saw the following BUG_ON triggered in a testcase where a process calls
      madvise(MADV_SOFT_OFFLINE) on thps, along with a background process that
      calls migratepages command repeatedly (doing ping-pong among different
      NUMA nodes) for the first process:
      
         Soft offlining page 0x60000 at 0x700000600000
         __get_any_page: 0x60000 free buddy page
         page:ffffea0001800000 count:0 mapcount:-127 mapping:          (null) index:0x1
         flags: 0x1fffc0000000000()
         page dumped because: VM_BUG_ON_PAGE(atomic_read(&page->_count) == 0)
         ------------[ cut here ]------------
         kernel BUG at /src/linux-dev/include/linux/mm.h:342!
         invalid opcode: 0000 [#1] SMP DEBUG_PAGEALLOC
         Modules linked in: cfg80211 rfkill crc32c_intel serio_raw virtio_balloon i2c_piix4 virtio_blk virtio_net ata_generic pata_acpi
         CPU: 3 PID: 3035 Comm: test_alloc_gene Tainted: G           O    4.4.0-rc8-v4.4-rc8-160107-1501-00000-rc8+ #74
         Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
         task: ffff88007c63d5c0 ti: ffff88007c210000 task.ti: ffff88007c210000
         RIP: 0010:[<ffffffff8118998c>]  [<ffffffff8118998c>] put_page+0x5c/0x60
         RSP: 0018:ffff88007c213e00  EFLAGS: 00010246
         Call Trace:
           put_hwpoison_page+0x4e/0x80
           soft_offline_page+0x501/0x520
           SyS_madvise+0x6bc/0x6f0
           entry_SYSCALL_64_fastpath+0x12/0x6a
         Code: 8b fc ff ff 5b 5d c3 48 89 df e8 b0 fa ff ff 48 89 df 31 f6 e8 c6 7d ff ff 5b 5d c3 48 c7 c6 08 54 a2 81 48 89 df e8 a4 c5 01 00 <0f> 0b 66 90 66 66 66 66 90 55 48 89 e5 41 55 41 54 53 48 8b 47
         RIP  [<ffffffff8118998c>] put_page+0x5c/0x60
          RSP <ffff88007c213e00>
      
      The root cause resides in get_any_page() which retries to get a refcount
      of the page to be soft-offlined.  This function calls
      put_hwpoison_page(), expecting that the target page is putback to LRU
      list.  But it can be also freed to buddy.  So the second check need to
      care about such case.
      
      Fixes: af8fae7c ("mm/memory-failure.c: clean up soft_offline_page()")
      Signed-off-by: default avatarNaoya Horiguchi <n-horiguchi@ah.jp.nec.com>
      Cc: Sasha Levin <sasha.levin@oracle.com>
      Cc: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
      Cc: Vlastimil Babka <vbabka@suse.cz>
      Cc: Jerome Marchand <jmarchan@redhat.com>
      Cc: Andrea Arcangeli <aarcange@redhat.com>
      Cc: Hugh Dickins <hughd@google.com>
      Cc: Dave Hansen <dave.hansen@intel.com>
      Cc: Mel Gorman <mgorman@suse.de>
      Cc: Rik van Riel <riel@redhat.com>
      Cc: Steve Capper <steve.capper@linaro.org>
      Cc: Johannes Weiner <hannes@cmpxchg.org>
      Cc: Michal Hocko <mhocko@suse.cz>
      Cc: Christoph Lameter <cl@linux.com>
      Cc: David Rientjes <rientjes@google.com>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      a76ce1fb
    • Kyeongdon Kim's avatar
      zram: try vmalloc() after kmalloc() · 8f35126d
      Kyeongdon Kim authored
      commit d913897a upstream.
      
      When we're using LZ4 multi compression streams for zram swap, we found
      out page allocation failure message in system running test.  That was
      not only once, but a few(2 - 5 times per test).  Also, some failure
      cases were continually occurring to try allocation order 3.
      
      In order to make parallel compression private data, we should call
      kzalloc() with order 2/3 in runtime(lzo/lz4).  But if there is no order
      2/3 size memory to allocate in that time, page allocation fails.  This
      patch makes to use vmalloc() as fallback of kmalloc(), this prevents
      page alloc failure warning.
      
      After using this, we never found warning message in running test, also
      It could reduce process startup latency about 60-120ms in each case.
      
      For reference a call trace :
      
          Binder_1: page allocation failure: order:3, mode:0x10c0d0
          CPU: 0 PID: 424 Comm: Binder_1 Tainted: GW 3.10.49-perf-g991d02b-dirty #20
          Call trace:
            dump_backtrace+0x0/0x270
            show_stack+0x10/0x1c
            dump_stack+0x1c/0x28
            warn_alloc_failed+0xfc/0x11c
            __alloc_pages_nodemask+0x724/0x7f0
            __get_free_pages+0x14/0x5c
            kmalloc_order_trace+0x38/0xd8
            zcomp_lz4_create+0x2c/0x38
            zcomp_strm_alloc+0x34/0x78
            zcomp_strm_multi_find+0x124/0x1ec
            zcomp_strm_find+0xc/0x18
            zram_bvec_rw+0x2fc/0x780
            zram_make_request+0x25c/0x2d4
            generic_make_request+0x80/0xbc
            submit_bio+0xa4/0x15c
            __swap_writepage+0x218/0x230
            swap_writepage+0x3c/0x4c
            shrink_page_list+0x51c/0x8d0
            shrink_inactive_list+0x3f8/0x60c
            shrink_lruvec+0x33c/0x4cc
            shrink_zone+0x3c/0x100
            try_to_free_pages+0x2b8/0x54c
            __alloc_pages_nodemask+0x514/0x7f0
            __get_free_pages+0x14/0x5c
            proc_info_read+0x50/0xe4
            vfs_read+0xa0/0x12c
            SyS_read+0x44/0x74
          DMA: 3397*4kB (MC) 26*8kB (RC) 0*16kB 0*32kB 0*64kB 0*128kB 0*256kB
               0*512kB 0*1024kB 0*2048kB 0*4096kB = 13796kB
      
      [minchan@kernel.org: change vmalloc gfp and adding comment about gfp]
      [sergey.senozhatsky@gmail.com: tweak comments and styles]
      Signed-off-by: default avatarKyeongdon Kim <kyeongdon.kim@lge.com>
      Signed-off-by: default avatarMinchan Kim <minchan@kernel.org>
      Acked-by: default avatarSergey Senozhatsky <sergey.senozhatsky@gmail.com>
      Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      8f35126d
    • Sergey Senozhatsky's avatar
      zram/zcomp: use GFP_NOIO to allocate streams · 5ff3781e
      Sergey Senozhatsky authored
      commit 3d5fe03a upstream.
      
      We can end up allocating a new compression stream with GFP_KERNEL from
      within the IO path, which may result is nested (recursive) IO
      operations.  That can introduce problems if the IO path in question is a
      reclaimer, holding some locks that will deadlock nested IOs.
      
      Allocate streams and working memory using GFP_NOIO flag, forbidding
      recursive IO and FS operations.
      
      An example:
      
        inconsistent {IN-RECLAIM_FS-W} -> {RECLAIM_FS-ON-W} usage.
        git/20158 [HC0[0]:SC0[0]:HE1:SE1] takes:
         (jbd2_handle){+.+.?.}, at:  start_this_handle+0x4ca/0x555
        {IN-RECLAIM_FS-W} state was registered at:
           __lock_acquire+0x8da/0x117b
           lock_acquire+0x10c/0x1a7
           start_this_handle+0x52d/0x555
           jbd2__journal_start+0xb4/0x237
           __ext4_journal_start_sb+0x108/0x17e
           ext4_dirty_inode+0x32/0x61
           __mark_inode_dirty+0x16b/0x60c
           iput+0x11e/0x274
           __dentry_kill+0x148/0x1b8
           shrink_dentry_list+0x274/0x44a
           prune_dcache_sb+0x4a/0x55
           super_cache_scan+0xfc/0x176
           shrink_slab.part.14.constprop.25+0x2a2/0x4d3
           shrink_zone+0x74/0x140
           kswapd+0x6b7/0x930
           kthread+0x107/0x10f
           ret_from_fork+0x3f/0x70
        irq event stamp: 138297
        hardirqs last  enabled at (138297):  debug_check_no_locks_freed+0x113/0x12f
        hardirqs last disabled at (138296):  debug_check_no_locks_freed+0x33/0x12f
        softirqs last  enabled at (137818):  __do_softirq+0x2d3/0x3e9
        softirqs last disabled at (137813):  irq_exit+0x41/0x95
      
                     other info that might help us debug this:
         Possible unsafe locking scenario:
               CPU0
               ----
          lock(jbd2_handle);
          <Interrupt>
            lock(jbd2_handle);
      
                      *** DEADLOCK ***
        5 locks held by git/20158:
         #0:  (sb_writers#7){.+.+.+}, at: [<ffffffff81155411>] mnt_want_write+0x24/0x4b
         #1:  (&type->i_mutex_dir_key#2/1){+.+.+.}, at: [<ffffffff81145087>] lock_rename+0xd9/0xe3
         #2:  (&sb->s_type->i_mutex_key#11){+.+.+.}, at: [<ffffffff8114f8e2>] lock_two_nondirectories+0x3f/0x6b
         #3:  (&sb->s_type->i_mutex_key#11/4){+.+.+.}, at: [<ffffffff8114f909>] lock_two_nondirectories+0x66/0x6b
         #4:  (jbd2_handle){+.+.?.}, at: [<ffffffff811e31db>] start_this_handle+0x4ca/0x555
      
                     stack backtrace:
        CPU: 2 PID: 20158 Comm: git Not tainted 4.1.0-rc7-next-20150615-dbg-00016-g8bdf555-dirty #211
        Call Trace:
          dump_stack+0x4c/0x6e
          mark_lock+0x384/0x56d
          mark_held_locks+0x5f/0x76
          lockdep_trace_alloc+0xb2/0xb5
          kmem_cache_alloc_trace+0x32/0x1e2
          zcomp_strm_alloc+0x25/0x73 [zram]
          zcomp_strm_multi_find+0xe7/0x173 [zram]
          zcomp_strm_find+0xc/0xe [zram]
          zram_bvec_rw+0x2ca/0x7e0 [zram]
          zram_make_request+0x1fa/0x301 [zram]
          generic_make_request+0x9c/0xdb
          submit_bio+0xf7/0x120
          ext4_io_submit+0x2e/0x43
          ext4_bio_write_page+0x1b7/0x300
          mpage_submit_page+0x60/0x77
          mpage_map_and_submit_buffers+0x10f/0x21d
          ext4_writepages+0xc8c/0xe1b
          do_writepages+0x23/0x2c
          __filemap_fdatawrite_range+0x84/0x8b
          filemap_flush+0x1c/0x1e
          ext4_alloc_da_blocks+0xb8/0x117
          ext4_rename+0x132/0x6dc
          ? mark_held_locks+0x5f/0x76
          ext4_rename2+0x29/0x2b
          vfs_rename+0x540/0x636
          SyS_renameat2+0x359/0x44d
          SyS_rename+0x1e/0x20
          entry_SYSCALL_64_fastpath+0x12/0x6f
      
      [minchan@kernel.org: add stable mark]
      Signed-off-by: default avatarSergey Senozhatsky <sergey.senozhatsky@gmail.com>
      Acked-by: default avatarMinchan Kim <minchan@kernel.org>
      Cc: Kyeongdon Kim <kyeongdon.kim@lge.com>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      5ff3781e
    • Takashi Iwai's avatar
      ALSA: timer: Harden slave timer list handling · c4ec805c
      Takashi Iwai authored
      commit b5a663aa upstream.
      
      A slave timer instance might be still accessible in a racy way while
      operating the master instance as it lacks of locking.  Since the
      master operation is mostly protected with timer->lock, we should cope
      with it while changing the slave instance, too.  Also, some linked
      lists (active_list and ack_list) of slave instances aren't unlinked
      immediately at stopping or closing, and this may lead to unexpected
      accesses.
      
      This patch tries to address these issues.  It adds spin lock of
      timer->lock (either from master or slave, which is equivalent) in a
      few places.  For avoiding a deadlock, we ensure that the global
      slave_active_lock is always locked at first before each timer lock.
      
      Also, ack and active_list of slave instances are properly unlinked at
      snd_timer_stop() and snd_timer_close().
      
      Last but not least, remove the superfluous call of _snd_timer_stop()
      at removing slave links.  This is a noop, and calling it may confuse
      readers wrt locking.  Further cleanup will follow in a later patch.
      
      Actually we've got reports of use-after-free by syzkaller fuzzer, and
      this hopefully fixes these issues.
      Reported-by: default avatarDmitry Vyukov <dvyukov@google.com>
      Signed-off-by: default avatarTakashi Iwai <tiwai@suse.de>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      c4ec805c
    • xuejiufei's avatar
      ocfs2/dlm: ignore cleaning the migration mle that is inuse · 477577b1
      xuejiufei authored
      commit bef5502d upstream.
      
      We have found that migration source will trigger a BUG that the refcount
      of mle is already zero before put when the target is down during
      migration.  The situation is as follows:
      
      dlm_migrate_lockres
        dlm_add_migration_mle
        dlm_mark_lockres_migrating
        dlm_get_mle_inuse
        <<<<<< Now the refcount of the mle is 2.
        dlm_send_one_lockres and wait for the target to become the
        new master.
        <<<<<< o2hb detect the target down and clean the migration
        mle. Now the refcount is 1.
      
      dlm_migrate_lockres woken, and put the mle twice when found the target
      goes down which trigger the BUG with the following message:
      
        "ERROR: bad mle: ".
      Signed-off-by: default avatarJiufei Xue <xuejiufei@huawei.com>
      Reviewed-by: default avatarJoseph Qi <joseph.qi@huawei.com>
      Cc: Mark Fasheh <mfasheh@suse.de>
      Cc: Joel Becker <jlbec@evilplan.org>
      Cc: Junxiao Bi <junxiao.bi@oracle.com>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      477577b1