1. 16 3月, 2016 18 次提交
  2. 10 3月, 2016 3 次提交
  3. 08 3月, 2016 2 次提交
  4. 07 3月, 2016 4 次提交
    • B
      xfs: only run torn log write detection on dirty logs · 7f6aff3a
      Brian Foster 提交于
      XFS uses CRC verification over a sub-range of the head of the log to
      detect and handle torn writes. This torn log write detection currently
      runs unconditionally at mount time, regardless of whether the log is
      dirty or clean. This is problematic in cases where a filesystem might
      end up being moved across different, incompatible (i.e., opposite
      byte-endianness) architectures.
      
      The problem lies in the fact that log data is not necessarily written in
      an architecture independent format. For example, certain bits of data
      are written in native endian format. Further, the size of certain log
      data structures differs (i.e., struct xlog_rec_header) depending on the
      word size of the cpu. This leads to false positive crc verification
      errors and ultimately failed mounts when a cleanly unmounted filesystem
      is mounted on a system with an incompatible architecture from data that
      was written near the head of the log.
      
      Update the log head/tail discovery code to run torn write detection only
      when the log is not clean. This means something other than an unmount
      record resides at the head of the log and log recovery is imminent. It
      is a requirement to run log recovery on the same type of host that had
      written the content of the dirty log and therefore CRC failures are
      legitimate corruptions in that scenario.
      Reported-by: NJan Beulich <JBeulich@suse.com>
      Tested-by: NJan Beulich <JBeulich@suse.com>
      Signed-off-by: NBrian Foster <bfoster@redhat.com>
      Reviewed-by: NDave Chinner <dchinner@redhat.com>
      Signed-off-by: NDave Chinner <david@fromorbit.com>
      
      7f6aff3a
    • B
      xfs: refactor in-core log state update to helper · 717bc0eb
      Brian Foster 提交于
      Once the record at the head of the log is identified and verified, the
      in-core log state is updated based on the record. This includes
      information such as the current head block and cycle, the start block of
      the last record written to the log, the tail lsn, etc.
      
      Once torn write detection is conditional, this logic will need to be
      reused. Factor the code to update the in-core log data structures into a
      new helper function. This patch does not change behavior.
      Signed-off-by: NBrian Foster <bfoster@redhat.com>
      Reviewed-by: NDave Chinner <dchinner@redhat.com>
      Signed-off-by: NDave Chinner <david@fromorbit.com>
      
      717bc0eb
    • B
      xfs: refactor unmount record detection into helper · 65b99a08
      Brian Foster 提交于
      Once the mount sequence has identified the head and tail blocks of the
      physical log, the record at the head of the log is located and examined
      for an unmount record to determine if the log is clean. This currently
      occurs after torn write verification of the head region of the log.
      
      This must ultimately be separated from torn write verification and may
      need to be called again if the log head is walked back due to a torn
      write (to determine whether the new head record is an unmount record).
      Separate this logic into a new helper function. This patch does not
      change behavior.
      Signed-off-by: NBrian Foster <bfoster@redhat.com>
      Reviewed-by: NDave Chinner <dchinner@redhat.com>
      Signed-off-by: NDave Chinner <david@fromorbit.com>
      
      65b99a08
    • B
      xfs: separate log head record discovery from verification · 82ff6cc2
      Brian Foster 提交于
      The code that locates the log record at the head of the log is buried in
      the log head verification function. This is fine when torn write
      verification occurs unconditionally, but this behavior is problematic
      for filesystems that might be moved across systems with different
      architectures.
      
      In preparation for separating examination of the log head for unmount
      records from torn write detection, lift the record location logic out of
      the log verification function and into the caller. This patch does not
      change behavior.
      Signed-off-by: NBrian Foster <bfoster@redhat.com>
      Reviewed-by: NDave Chinner <dchinner@redhat.com>
      Signed-off-by: NDave Chinner <david@fromorbit.com>
      
      82ff6cc2
  5. 05 3月, 2016 1 次提交
  6. 04 3月, 2016 6 次提交
    • F
      Btrfs: fix loading of orphan roots leading to BUG_ON · 909c3a22
      Filipe Manana 提交于
      When looking for orphan roots during mount we can end up hitting a
      BUG_ON() (at root-item.c:btrfs_find_orphan_roots()) if a log tree is
      replayed and qgroups are enabled. This is because after a log tree is
      replayed, a transaction commit is made, which triggers qgroup extent
      accounting which in turn does backref walking which ends up reading and
      inserting all roots in the radix tree fs_info->fs_root_radix, including
      orphan roots (deleted snapshots). So after the log tree is replayed, when
      finding orphan roots we hit the BUG_ON with the following trace:
      
      [118209.182438] ------------[ cut here ]------------
      [118209.183279] kernel BUG at fs/btrfs/root-tree.c:314!
      [118209.184074] invalid opcode: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC
      [118209.185123] Modules linked in: btrfs dm_flakey dm_mod crc32c_generic ppdev xor raid6_pq evdev sg parport_pc parport acpi_cpufreq tpm_tis tpm psmouse
      processor i2c_piix4 serio_raw pcspkr i2c_core button loop autofs4 ext4 crc16 mbcache jbd2 sd_mod sr_mod cdrom ata_generic virtio_scsi ata_piix libata
      virtio_pci virtio_ring virtio scsi_mod e1000 floppy [last unloaded: btrfs]
      [118209.186318] CPU: 14 PID: 28428 Comm: mount Tainted: G        W       4.5.0-rc5-btrfs-next-24+ #1
      [118209.186318] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS by qemu-project.org 04/01/2014
      [118209.186318] task: ffff8801ec131040 ti: ffff8800af34c000 task.ti: ffff8800af34c000
      [118209.186318] RIP: 0010:[<ffffffffa04237d7>]  [<ffffffffa04237d7>] btrfs_find_orphan_roots+0x1fc/0x244 [btrfs]
      [118209.186318] RSP: 0018:ffff8800af34faa8  EFLAGS: 00010246
      [118209.186318] RAX: 00000000ffffffef RBX: 00000000ffffffef RCX: 0000000000000001
      [118209.186318] RDX: 0000000080000000 RSI: 0000000000000001 RDI: 00000000ffffffff
      [118209.186318] RBP: ffff8800af34fb08 R08: 0000000000000001 R09: 0000000000000000
      [118209.186318] R10: ffff8800af34f9f0 R11: 6db6db6db6db6db7 R12: ffff880171b97000
      [118209.186318] R13: ffff8801ca9d65e0 R14: ffff8800afa2e000 R15: 0000160000000000
      [118209.186318] FS:  00007f5bcb914840(0000) GS:ffff88023edc0000(0000) knlGS:0000000000000000
      [118209.186318] CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
      [118209.186318] CR2: 00007f5bcaceb5d9 CR3: 00000000b49b5000 CR4: 00000000000006e0
      [118209.186318] Stack:
      [118209.186318]  fffffbffffffffff 010230ffffffffff 0101000000000000 ff84000000000000
      [118209.186318]  fbffffffffffffff 30ffffffffffffff 0000000000000101 ffff880082348000
      [118209.186318]  0000000000000000 ffff8800afa2e000 ffff8800afa2e000 0000000000000000
      [118209.186318] Call Trace:
      [118209.186318]  [<ffffffffa042e2db>] open_ctree+0x1e37/0x21b9 [btrfs]
      [118209.186318]  [<ffffffffa040a753>] btrfs_mount+0x97e/0xaed [btrfs]
      [118209.186318]  [<ffffffff8108e1c0>] ? trace_hardirqs_on+0xd/0xf
      [118209.186318]  [<ffffffff8117b87e>] mount_fs+0x67/0x131
      [118209.186318]  [<ffffffff81192d2b>] vfs_kern_mount+0x6c/0xde
      [118209.186318]  [<ffffffffa0409f81>] btrfs_mount+0x1ac/0xaed [btrfs]
      [118209.186318]  [<ffffffff8108e1c0>] ? trace_hardirqs_on+0xd/0xf
      [118209.186318]  [<ffffffff8108c26b>] ? lockdep_init_map+0xb9/0x1b3
      [118209.186318]  [<ffffffff8117b87e>] mount_fs+0x67/0x131
      [118209.186318]  [<ffffffff81192d2b>] vfs_kern_mount+0x6c/0xde
      [118209.186318]  [<ffffffff81195637>] do_mount+0x8a6/0x9e8
      [118209.186318]  [<ffffffff8119598d>] SyS_mount+0x77/0x9f
      [118209.186318]  [<ffffffff81493017>] entry_SYSCALL_64_fastpath+0x12/0x6b
      [118209.186318] Code: 64 00 00 85 c0 89 c3 75 24 f0 41 80 4c 24 20 20 49 8b bc 24 f0 01 00 00 4c 89 e6 e8 e8 65 00 00 85 c0 89 c3 74 11 83 f8 ef 75 02 <0f> 0b
      4c 89 e7 e8 da 72 00 00 eb 1c 41 83 bc 24 00 01 00 00 00
      [118209.186318] RIP  [<ffffffffa04237d7>] btrfs_find_orphan_roots+0x1fc/0x244 [btrfs]
      [118209.186318]  RSP <ffff8800af34faa8>
      [118209.230735] ---[ end trace 83938f987d85d477 ]---
      
      So fix this by not treating the error -EEXIST, returned when attempting
      to insert a root already inserted by the backref walking code, as an error.
      
      The following test case for xfstests reproduces the bug:
      
        seq=`basename $0`
        seqres=$RESULT_DIR/$seq
        echo "QA output created by $seq"
        tmp=/tmp/$$
        status=1	# failure is the default!
        trap "_cleanup; exit \$status" 0 1 2 3 15
      
        _cleanup()
        {
            _cleanup_flakey
            cd /
            rm -f $tmp.*
        }
      
        # get standard environment, filters and checks
        . ./common/rc
        . ./common/filter
        . ./common/dmflakey
      
        # real QA test starts here
        _supported_fs btrfs
        _supported_os Linux
        _require_scratch
        _require_dm_target flakey
        _require_metadata_journaling $SCRATCH_DEV
      
        rm -f $seqres.full
      
        _scratch_mkfs >>$seqres.full 2>&1
        _init_flakey
        _mount_flakey
      
        _run_btrfs_util_prog quota enable $SCRATCH_MNT
      
        # Create 2 directories with one file in one of them.
        # We use these just to trigger a transaction commit later, moving the file from
        # directory a to directory b and doing an fsync against directory a.
        mkdir $SCRATCH_MNT/a
        mkdir $SCRATCH_MNT/b
        touch $SCRATCH_MNT/a/f
        sync
      
        # Create our test file with 2 4K extents.
        $XFS_IO_PROG -f -s -c "pwrite -S 0xaa 0 8K" $SCRATCH_MNT/foobar | _filter_xfs_io
      
        # Create a snapshot and delete it. This doesn't really delete the snapshot
        # immediately, just makes it inaccessible and invisible to user space, the
        # snapshot is deleted later by a dedicated kernel thread (cleaner kthread)
        # which is woke up at the next transaction commit.
        # A root orphan item is inserted into the tree of tree roots, so that if a
        # power failure happens before the dedicated kernel thread does the snapshot
        # deletion, the next time the filesystem is mounted it resumes the snapshot
        # deletion.
        _run_btrfs_util_prog subvolume snapshot $SCRATCH_MNT $SCRATCH_MNT/snap
        _run_btrfs_util_prog subvolume delete $SCRATCH_MNT/snap
      
        # Now overwrite half of the extents we wrote before. Because we made a snapshpot
        # before, which isn't really deleted yet (since no transaction commit happened
        # after we did the snapshot delete request), the non overwritten extents get
        # referenced twice, once by the default subvolume and once by the snapshot.
        $XFS_IO_PROG -c "pwrite -S 0xbb 4K 8K" $SCRATCH_MNT/foobar | _filter_xfs_io
      
        # Now move file f from directory a to directory b and fsync directory a.
        # The fsync on the directory a triggers a transaction commit (because a file
        # was moved from it to another directory) and the file fsync leaves a log tree
        # with file extent items to replay.
        mv $SCRATCH_MNT/a/f $SCRATCH_MNT/a/b
        $XFS_IO_PROG -c "fsync" $SCRATCH_MNT/a
        $XFS_IO_PROG -c "fsync" $SCRATCH_MNT/foobar
      
        echo "File digest before power failure:"
        md5sum $SCRATCH_MNT/foobar | _filter_scratch
      
        # Now simulate a power failure and mount the filesystem to replay the log tree.
        # After the log tree was replayed, we used to hit a BUG_ON() when processing
        # the root orphan item for the deleted snapshot. This is because when processing
        # an orphan root the code expected to be the first code inserting the root into
        # the fs_info->fs_root_radix radix tree, while in reallity it was the second
        # caller attempting to do it - the first caller was the transaction commit that
        # took place after replaying the log tree, when updating the qgroup counters.
        _flakey_drop_and_remount
      
        echo "File digest before after failure:"
        # Must match what he got before the power failure.
        md5sum $SCRATCH_MNT/foobar | _filter_scratch
      
        _unmount_flakey
        status=0
        exit
      
      Fixes: 2d9e9776 ("Btrfs: use btrfs_get_fs_root in resolve_indirect_ref")
      Cc: stable@vger.kernel.org  # 4.4+
      Signed-off-by: NFilipe Manana <fdmanana@suse.com>
      Reviewed-by: NQu Wenruo <quwenruo@cn.fujitsu.com>
      Signed-off-by: NChris Mason <clm@fb.com>
      909c3a22
    • T
      writeback: flush inode cgroup wb switches instead of pinning super_block · a1a0e23e
      Tejun Heo 提交于
      If cgroup writeback is in use, inodes can be scheduled for
      asynchronous wb switching.  Before 5ff8eaac ("writeback: keep
      superblock pinned during cgroup writeback association switches"), this
      could race with umount leading to super_block being destroyed while
      inodes are pinned for wb switching.  5ff8eaac fixed it by bumping
      s_active while wb switches are in flight; however, this allowed
      in-flight wb switches to make umounts asynchronous when the userland
      expected synchronosity - e.g. fsck immediately following umount may
      fail because the device is still busy.
      
      This patch removes the problematic super_block pinning and instead
      makes generic_shutdown_super() flush in-flight wb switches.  wb
      switches are now executed on a dedicated isw_wq so that they can be
      flushed and isw_nr_in_flight keeps track of the number of in-flight wb
      switches so that flushing can be avoided in most cases.
      
      v2: Move cgroup_writeback_umount() further below and add MS_ACTIVE
          check in inode_switch_wbs() as Jan an Al suggested.
      Signed-off-by: NTejun Heo <tj@kernel.org>
      Reported-by: NTahsin Erdogan <tahsin@google.com>
      Cc: Jan Kara <jack@suse.cz>
      Cc: Al Viro <viro@ZenIV.linux.org.uk>
      Link: http://lkml.kernel.org/g/CAAeU0aNCq7LGODvVGRU-oU_o-6enii5ey0p1c26D1ZzYwkDc5A@mail.gmail.com
      Fixes: 5ff8eaac ("writeback: keep superblock pinned during cgroup writeback association switches")
      Cc: stable@vger.kernel.org #v4.5
      Reviewed-by: NJan Kara <jack@suse.cz>
      Tested-by: NTahsin Erdogan <tahsin@google.com>
      Signed-off-by: NJens Axboe <axboe@fb.com>
      a1a0e23e
    • K
      ovl: copy new uid/gid into overlayfs runtime inode · b81de061
      Konstantin Khlebnikov 提交于
      Overlayfs must update uid/gid after chown, otherwise functions
      like inode_owner_or_capable() will check user against stale uid.
      Catched by xfstests generic/087, it chowns file and calls utimes.
      Signed-off-by: NKonstantin Khlebnikov <koct9i@gmail.com>
      Signed-off-by: NMiklos Szeredi <miklos@szeredi.hu>
      Cc: <stable@vger.kernel.org>
      b81de061
    • K
      ovl: ignore lower entries when checking purity of non-directory entries · 45d11738
      Konstantin Khlebnikov 提交于
      After rename file dentry still holds reference to lower dentry from
      previous location. This doesn't matter for data access because data comes
      from upper dentry. But this stale lower dentry taints dentry at new
      location and turns it into non-pure upper. Such file leaves visible
      whiteout entry after remove in directory which shouldn't have whiteouts at
      all.
      
      Overlayfs already tracks pureness of file location in oe->opaque.  This
      patch just uses that for detecting actual path type.
      
      Comment from Vivek Goyal's patch:
      
      Here are the details of the problem. Do following.
      
      $ mkdir upper lower work merged upper/dir/
      $ touch lower/test
      $ sudo mount -t overlay overlay -olowerdir=lower,upperdir=upper,workdir=
      work merged
      $ mv merged/test merged/dir/
      $ rm merged/dir/test
      $ ls -l merged/dir/
      /usr/bin/ls: cannot access merged/dir/test: No such file or directory
      total 0
      c????????? ? ? ? ?            ? test
      
      Basic problem seems to be that once a file has been unlinked, a whiteout
      has been left behind which was not needed and hence it becomes visible.
      
      Whiteout is visible because parent dir is of not type MERGE, hence
      od->is_real is set during ovl_dir_open(). And that means ovl_iterate()
      passes on iterate handling directly to underlying fs. Underlying fs does
      not know/filter whiteouts so it becomes visible to user.
      
      Why did we leave a whiteout to begin with when we should not have.
      ovl_do_remove() checks for OVL_TYPE_PURE_UPPER() and does not leave
      whiteout if file is pure upper. In this case file is not found to be pure
      upper hence whiteout is left.
      
      So why file was not PURE_UPPER in this case? I think because dentry is
      still carrying some leftover state which was valid before rename. For
      example, od->numlower was set to 1 as it was a lower file. After rename,
      this state is not valid anymore as there is no such file in lower.
      Signed-off-by: NKonstantin Khlebnikov <koct9i@gmail.com>
      Reported-by: NViktor Stanchev <me@viktorstanchev.com>
      Suggested-by: NVivek Goyal <vgoyal@redhat.com>
      Link: https://bugzilla.kernel.org/show_bug.cgi?id=109611Acked-by: NVivek Goyal <vgoyal@redhat.com>
      Signed-off-by: NMiklos Szeredi <miklos@szeredi.hu>
      Cc: <stable@vger.kernel.org>
      45d11738
    • R
      ovl: fix getcwd() failure after unsuccessful rmdir · ce9113bb
      Rui Wang 提交于
      ovl_remove_upper() should do d_drop() only after it successfully
      removes the dir, otherwise a subsequent getcwd() system call will
      fail, breaking userspace programs.
      
      This is to fix: https://bugzilla.kernel.org/show_bug.cgi?id=110491Signed-off-by: NRui Wang <rui.y.wang@intel.com>
      Reviewed-by: NKonstantin Khlebnikov <koct9i@gmail.com>
      Signed-off-by: NMiklos Szeredi <miklos@szeredi.hu>
      Cc: <stable@vger.kernel.org>
      ce9113bb
    • K
      ovl: fix working on distributed fs as lower layer · b5891cfa
      Konstantin Khlebnikov 提交于
      This adds missing .d_select_inode into alternative dentry_operations.
      Signed-off-by: NKonstantin Khlebnikov <koct9i@gmail.com>
      Fixes: 7c03b5d4 ("ovl: allow distributed fs as lower layer")
      Fixes: 4bacc9c9 ("overlayfs: Make f_path always point to the overlay and f_inode to the underlay")
      Reviewed-by: NNikolay Borisov <kernel@kyup.com>
      Tested-by: NNikolay Borisov <kernel@kyup.com>
      Signed-off-by: NMiklos Szeredi <miklos@szeredi.hu>
      Cc: <stable@vger.kernel.org> # 4.2+
      b5891cfa
  7. 03 3月, 2016 1 次提交
    • L
      userfaultfd: don't block on the last VM updates at exit time · 39680f50
      Linus Torvalds 提交于
      The exit path will do some final updates to the VM of an exiting process
      to inform others of the fact that the process is going away.
      
      That happens, for example, for robust futex state cleanup, but also if
      the parent has asked for a TID update when the process exits (we clear
      the child tid field in user space).
      
      However, at the time we do those final VM accesses, we've already
      stopped accepting signals, so the usual "stop waiting for userfaults on
      signal" code in fs/userfaultfd.c no longer works, and the process can
      become an unkillable zombie waiting for something that will never
      happen.
      
      To solve this, just make handle_userfault() abort any user fault
      handling if we're already in the exit path past the signal handling
      state being dead (marked by PF_EXITING).
      
      This VM special case is pretty ugly, and it is possible that we should
      look at finalizing signals later (or move the VM final accesses
      earlier).  But in the meantime this is a fairly minimally intrusive fix.
      Reported-and-tested-by: NDmitry Vyukov <dvyukov@google.com>
      Acked-by: NAndrea Arcangeli <aarcange@redhat.com>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      39680f50
  8. 01 3月, 2016 2 次提交
  9. 29 2月, 2016 3 次提交
    • Y
      Fix cifs_uniqueid_to_ino_t() function for s390x · 1ee9f4bd
      Yadan Fan 提交于
      This issue is caused by commit 02323db1 ("cifs: fix
      cifs_uniqueid_to_ino_t not to ever return 0"), when BITS_PER_LONG
      is 64 on s390x, the corresponding cifs_uniqueid_to_ino_t()
      function will cast 64-bit fileid to 32-bit by using (ino_t)fileid,
      because ino_t (typdefed __kernel_ino_t) is int type.
      
      It's defined in arch/s390/include/uapi/asm/posix_types.h
      
          #ifndef __s390x__
      
          typedef unsigned long   __kernel_ino_t;
          ...
          #else /* __s390x__ */
      
          typedef unsigned int    __kernel_ino_t;
      
      So the #ifdef condition is wrong for s390x, we can just still use
      one cifs_uniqueid_to_ino_t() function with comparing sizeof(ino_t)
      and sizeof(u64) to choose the correct execution accordingly.
      Signed-off-by: NYadan Fan <ydfan@suse.com>
      CC: stable <stable@vger.kernel.org>
      Signed-off-by: NSteve French <smfrench@gmail.com>
      1ee9f4bd
    • P
      CIFS: Fix SMB2+ interim response processing for read requests · 6cc3b242
      Pavel Shilovsky 提交于
      For interim responses we only need to parse a header and update
      a number credits. Now it is done for all SMB2+ command except
      SMB2_READ which is wrong. Fix this by adding such processing.
      Signed-off-by: NPavel Shilovsky <pshilovsky@samba.org>
      Tested-by: NShirish Pargaonkar <shirishpargaonkar@gmail.com>
      CC: Stable <stable@vger.kernel.org>
      Signed-off-by: NSteve French <smfrench@gmail.com>
      6cc3b242
    • J
      cifs: fix out-of-bounds access in lease parsing · deb7deff
      Justin Maggard 提交于
      When opening a file, SMB2_open() attempts to parse the lease state from the
      SMB2 CREATE Response.  However, the parsing code was not careful to ensure
      that the create contexts are not empty or invalid, which can lead to out-
      of-bounds memory access.  This can be seen easily by trying
      to read a file from a OSX 10.11 SMB3 server.  Here is sample crash output:
      
      BUG: unable to handle kernel paging request at ffff8800a1a77cc6
      IP: [<ffffffff8828a734>] SMB2_open+0x804/0x960
      PGD 8f77067 PUD 0
      Oops: 0000 [#1] SMP
      Modules linked in:
      CPU: 3 PID: 2876 Comm: cp Not tainted 4.5.0-rc3.x86_64.1+ #14
      Hardware name: NETGEAR ReadyNAS 314          /ReadyNAS 314          , BIOS 4.6.5 10/11/2012
      task: ffff880073cdc080 ti: ffff88005b31c000 task.ti: ffff88005b31c000
      RIP: 0010:[<ffffffff8828a734>]  [<ffffffff8828a734>] SMB2_open+0x804/0x960
      RSP: 0018:ffff88005b31fa08  EFLAGS: 00010282
      RAX: 0000000000000015 RBX: 0000000000000000 RCX: 0000000000000006
      RDX: 0000000000000000 RSI: 0000000000000246 RDI: ffff88007eb8c8b0
      RBP: ffff88005b31fad8 R08: 666666203d206363 R09: 6131613030383866
      R10: 3030383866666666 R11: 00000000000002b0 R12: ffff8800660fd800
      R13: ffff8800a1a77cc2 R14: 00000000424d53fe R15: ffff88005f5a28c0
      FS:  00007f7c8a2897c0(0000) GS:ffff88007eb80000(0000) knlGS:0000000000000000
      CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
      CR2: ffff8800a1a77cc6 CR3: 000000005b281000 CR4: 00000000000006e0
      Stack:
       ffff88005b31fa70 ffffffff88278789 00000000000001d3 ffff88005f5a2a80
       ffffffff00000003 ffff88005d029d00 ffff88006fde05a0 0000000000000000
       ffff88005b31fc78 ffff88006fde0780 ffff88005b31fb2f 0000000100000fe0
      Call Trace:
       [<ffffffff88278789>] ? cifsConvertToUTF16+0x159/0x2d0
       [<ffffffff8828cf68>] smb2_open_file+0x98/0x210
       [<ffffffff8811e80c>] ? __kmalloc+0x1c/0xe0
       [<ffffffff882685f4>] cifs_open+0x2a4/0x720
       [<ffffffff88122cef>] do_dentry_open+0x1ff/0x310
       [<ffffffff88268350>] ? cifsFileInfo_get+0x30/0x30
       [<ffffffff88123d92>] vfs_open+0x52/0x60
       [<ffffffff88131dd0>] path_openat+0x170/0xf70
       [<ffffffff88097d48>] ? remove_wait_queue+0x48/0x50
       [<ffffffff88133a29>] do_filp_open+0x79/0xd0
       [<ffffffff8813f2ca>] ? __alloc_fd+0x3a/0x170
       [<ffffffff881240c4>] do_sys_open+0x114/0x1e0
       [<ffffffff881241a9>] SyS_open+0x19/0x20
       [<ffffffff8896e257>] entry_SYSCALL_64_fastpath+0x12/0x6a
      Code: 4d 8d 6c 07 04 31 c0 4c 89 ee e8 47 6f e5 ff 31 c9 41 89 ce 44 89 f1 48 c7 c7 28 b1 bd 88 31 c0 49 01 cd 4c 89 ee e8 2b 6f e5 ff <45> 0f b7 75 04 48 c7 c7 31 b1 bd 88 31 c0 4d 01 ee 4c 89 f6 e8
      RIP  [<ffffffff8828a734>] SMB2_open+0x804/0x960
       RSP <ffff88005b31fa08>
      CR2: ffff8800a1a77cc6
      ---[ end trace d9f69ba64feee469 ]---
      Signed-off-by: NJustin Maggard <jmaggard@netgear.com>
      Signed-off-by: NSteve French <smfrench@gmail.com>
      CC: Stable <stable@vger.kernel.org>
      deb7deff