linux-stable.git/fs, branch v4.20.7

cifs: Always resolve hostname before reconnecting

2019-02-06T16:27:45+00:00

commit 28eb24ff75c5ac130eb326b3b4d0dcecfc0f427d upstream.

In case a hostname resolves to a different IP address (e.g. long
running mounts), make sure to resolve it every time prior to calling
generic_ip_connect() in reconnect.

Suggested-by: Steve French 
Signed-off-by: Paulo Alcantara 
Signed-off-by: Steve French 
Signed-off-by: Pavel Shilovsky 
Signed-off-by: Greg Kroah-Hartman

btrfs: On error always free subvol_name in btrfs_mount

2019-02-06T16:27:43+00:00

commit 532b618bdf237250d6d4566536d4b6ce3d0a31fe upstream.

The subvol_name is allocated in btrfs_parse_subvol_options and is
consumed and freed in mount_subvol.  Add a free to the error paths that
don't call mount_subvol so that it is guaranteed that subvol_name is
freed when an error happens.

Fixes: 312c89fbca06 ("btrfs: cleanup btrfs_mount() using btrfs_mount_root()")
Cc: stable@vger.kernel.org # v4.19+
Reviewed-by: Nikolay Borisov 
Signed-off-by: "Eric W. Biederman" 
Reviewed-by: David Sterba 
Signed-off-by: David Sterba 
Signed-off-by: Greg Kroah-Hartman

Btrfs: fix deadlock when allocating tree block during leaf/node split

2019-02-06T16:27:43+00:00

commit a6279470762c19ba97e454f90798373dccdf6148 upstream.

When splitting a leaf or node from one of the trees that are modified when
flushing pending block groups (extent, chunk, device and free space trees),
we need to allocate a new tree block, which in turn can result in the need
to allocate a new block group. After allocating the new block group we may
need to flush new block groups that were previously allocated during the
course of the current transaction, which is what may cause a deadlock due
to attempts to write lock twice the same leaf or node, as when splitting
a leaf or node we are holding a write lock on it and its parent node.

The same type of deadlock can also happen when increasing the tree's
height, since we are holding a lock on the existing root while allocating
the tree block to use as the new root node.

An example trace when the deadlock happens during the leaf split path is:

  [27175.293054] CPU: 0 PID: 3005 Comm: kworker/u17:6 Tainted: G        W         4.19.16 #1
  [27175.293942] Hardware name: Penguin Computing Relion 1900/MD90-FS0-ZB-XX, BIOS R15 06/25/2018
  [27175.294846] Workqueue: btrfs-extent-refs btrfs_extent_refs_helper [btrfs]
  (...)
  [27175.298384] RSP: 0018:ffffab2087107758 EFLAGS: 00010246
  [27175.299269] RAX: 0000000000000bbd RBX: ffff9fadc7141c48 RCX: 0000000000000001
  [27175.300155] RDX: 0000000000000001 RSI: 0000000000000002 RDI: ffff9fadc7141c48
  [27175.301023] RBP: 0000000000000001 R08: ffff9faeb6ac1040 R09: ffff9fa9c0000000
  [27175.301887] R10: 0000000000000000 R11: 0000000000000040 R12: ffff9fb21aac8000
  [27175.302743] R13: ffff9fb1a64d6a20 R14: 0000000000000001 R15: ffff9fb1a64d6a18
  [27175.303601] FS:  0000000000000000(0000) GS:ffff9fb21fa00000(0000) knlGS:0000000000000000
  [27175.304468] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  [27175.305339] CR2: 00007fdc8743ead8 CR3: 0000000763e0a006 CR4: 00000000003606f0
  [27175.306220] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
  [27175.307087] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
  [27175.307940] Call Trace:
  [27175.308802]  btrfs_search_slot+0x779/0x9a0 [btrfs]
  [27175.309669]  ? update_space_info+0xba/0xe0 [btrfs]
  [27175.310534]  btrfs_insert_empty_items+0x67/0xc0 [btrfs]
  [27175.311397]  btrfs_insert_item+0x60/0xd0 [btrfs]
  [27175.312253]  btrfs_create_pending_block_groups+0xee/0x210 [btrfs]
  [27175.313116]  do_chunk_alloc+0x25f/0x300 [btrfs]
  [27175.313984]  find_free_extent+0x706/0x10d0 [btrfs]
  [27175.314855]  btrfs_reserve_extent+0x9b/0x1d0 [btrfs]
  [27175.315707]  btrfs_alloc_tree_block+0x100/0x5b0 [btrfs]
  [27175.316548]  split_leaf+0x130/0x610 [btrfs]
  [27175.317390]  btrfs_search_slot+0x94d/0x9a0 [btrfs]
  [27175.318235]  btrfs_insert_empty_items+0x67/0xc0 [btrfs]
  [27175.319087]  alloc_reserved_file_extent+0x84/0x2c0 [btrfs]
  [27175.319938]  __btrfs_run_delayed_refs+0x596/0x1150 [btrfs]
  [27175.320792]  btrfs_run_delayed_refs+0xed/0x1b0 [btrfs]
  [27175.321643]  delayed_ref_async_start+0x81/0x90 [btrfs]
  [27175.322491]  normal_work_helper+0xd0/0x320 [btrfs]
  [27175.323328]  ? move_linked_works+0x6e/0xa0
  [27175.324160]  process_one_work+0x191/0x370
  [27175.324976]  worker_thread+0x4f/0x3b0
  [27175.325763]  kthread+0xf8/0x130
  [27175.326531]  ? rescuer_thread+0x320/0x320
  [27175.327284]  ? kthread_create_worker_on_cpu+0x50/0x50
  [27175.328027]  ret_from_fork+0x35/0x40
  [27175.328741] ---[ end trace 300a1b9f0ac30e26 ]---

Fix this by preventing the flushing of new blocks groups when splitting a
leaf/node and when inserting a new root node for one of the trees modified
by the flushing operation, similar to what is done when COWing a node/leaf
from on of these trees.

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=202383
Reported-by: Eli V 
CC: stable@vger.kernel.org # 4.4+
Signed-off-by: Filipe Manana 
Signed-off-by: David Sterba 
Signed-off-by: Greg Kroah-Hartman

gfs2: Revert "Fix loop in gfs2_rbm_find"

2019-02-06T16:27:42+00:00

commit e74c98ca2d6ae4376cc15fa2a22483430909d96b upstream.

This reverts commit 2d29f6b96d8f80322ed2dd895bca590491c38d34.

It turns out that the fix can lead to a ~20 percent performance regression
in initial writes to the page cache according to iozone.  Let's revert this
for now to have more time for a proper fix.

Cc: stable@vger.kernel.org # v3.13+
Signed-off-by: Andreas Gruenbacher 
Signed-off-by: Bob Peterson 
Signed-off-by: Linus Torvalds 
Signed-off-by: Greg Kroah-Hartman

NFS: Fix up return value on fatal errors in nfs_page_async_flush()

2019-02-06T16:27:40+00:00

commit 8fc75bed96bb94e23ca51bd9be4daf65c57697bf upstream.

Ensure that we return the fatal error value that caused us to exit
nfs_page_async_flush().

Fixes: c373fff7bd25 ("NFSv4: Don't special case "launder"")
Signed-off-by: Trond Myklebust 
Cc: stable@vger.kernel.org # v4.12+
Reviewed-by: Benjamin Coddington 
Signed-off-by: Anna Schumaker 
Signed-off-by: Greg Kroah-Hartman

fs/dcache: Fix incorrect nr_dentry_unused accounting in shrink_dcache_sb()

2019-02-06T16:27:40+00:00

commit 1dbd449c9943e3145148cc893c2461b72ba6fef0 upstream.

The nr_dentry_unused per-cpu counter tracks dentries in both the LRU
lists and the shrink lists where the DCACHE_LRU_LIST bit is set.

The shrink_dcache_sb() function moves dentries from the LRU list to a
shrink list and subtracts the dentry count from nr_dentry_unused.  This
is incorrect as the nr_dentry_unused count will also be decremented in
shrink_dentry_list() via d_shrink_del().

To fix this double decrement, the decrement in the shrink_dcache_sb()
function is taken out.

Fixes: 4e717f5c1083 ("list_lru: remove special case function list_lru_dispose_all."
Cc: stable@kernel.org
Signed-off-by: Waiman Long 
Reviewed-by: Dave Chinner 
Signed-off-by: Linus Torvalds 
Signed-off-by: Greg Kroah-Hartman

CIFS: Do not consider -ENODATA as stat failure for reads

2019-02-06T16:27:40+00:00

commit 082aaa8700415f6471ec9c5ef0c8307ca214989a upstream.

When doing reads beyound the end of a file the server returns
error STATUS_END_OF_FILE error which is mapped to -ENODATA.
Currently we report it as a failure which confuses read stats.
Change it to not consider -ENODATA as failure for stat purposes.

Signed-off-by: Pavel Shilovsky 
Signed-off-by: Steve French 
CC: Stable 
Signed-off-by: Greg Kroah-Hartman

CIFS: fix use-after-free of the lease keys

2019-02-06T16:27:40+00:00

commit d339adc12a4f885b572c5412e4869af8939db854 upstream.

The request buffers are freed right before copying the pointers.
Use the func args instead which are identical and still valid.

Simple reproducer (requires KASAN enabled) on a cifs mount:

echo foo > foo ; tail -f foo & rm foo

Cc:  # 4.20
Fixes: 179e44d49c2f ("smb3: add tracepoint for sending lease break responses to server")
Signed-off-by: Aurelien Aptel 
Signed-off-by: Steve French 
Reviewed-by: Paulo Alcantara 
Signed-off-by: Greg Kroah-Hartman

CIFS: Fix trace command logging for SMB2 reads and writes

2019-02-06T16:27:40+00:00

commit 7d42e72fe8ee5ab70b1af843dd7d8615e6fb0abe upstream.

Currently we log success once we send an async IO request to
the server. Instead we need to analyse a response and then log
success or failure for a particular command. Also fix argument
list for read logging.

Cc:  # 4.18
Signed-off-by: Pavel Shilovsky 
Signed-off-by: Steve French 
Signed-off-by: Greg Kroah-Hartman

CIFS: Fix possible oops and memory leaks in async IO

2019-02-06T16:27:39+00:00

commit 9bda8723da2d55b1de833b98cf802b88006e5b69 upstream.

Allocation of a page array for non-cached IO was separated from
allocation of rdata and wdata structures and this introduced memory
leaks and a possible null pointer dereference. This patch fixes
these problems.

Cc: 
Signed-off-by: Pavel Shilovsky 
Signed-off-by: Steve French 
Signed-off-by: Greg Kroah-Hartman