litmus-rt-ext-res.git/fs/cifs, branch EXT-RES

CIFS: add misssing SFM mapping for doublequote

2017-05-20T12:28:40+00:00

commit 85435d7a15294f9f7ef23469e6aaf7c5dfcc54f0 upstream.

SFM is mapping doublequote to 0xF020

Without this patch creating files with doublequote fails to Windows/Mac

Signed-off-by: Bjoern Jacke 
Signed-off-by: Steve French 
Signed-off-by: Greg Kroah-Hartman

cifs: fix CIFS_IOC_GET_MNT_INFO oops

2017-05-20T12:28:40+00:00

commit d8a6e505d6bba2250852fbc1c1c86fe68aaf9af3 upstream.

An open directory may have a NULL private_data pointer prior to readdir.

Fixes: 0de1f4c6f6c0 ("Add way to query server fs info for smb3")
Signed-off-by: David Disseldorp 
Signed-off-by: Steve French 
Signed-off-by: Greg Kroah-Hartman

CIFS: fix oplock break deadlocks

2017-05-20T12:28:40+00:00

commit 3998e6b87d4258a70df358296d6f1c7234012bfe upstream.

When the final cifsFileInfo_put() is called from cifsiod and an oplock
break work is queued, lockdep complains loudly:

 =============================================
 [ INFO: possible recursive locking detected ]
 4.11.0+ #21 Not tainted
 ---------------------------------------------
 kworker/0:2/78 is trying to acquire lock:
  ("cifsiod"){++++.+}, at: flush_work+0x215/0x350

 but task is already holding lock:
  ("cifsiod"){++++.+}, at: process_one_work+0x255/0x8e0

 other info that might help us debug this:
  Possible unsafe locking scenario:

        CPU0
        ----
   lock("cifsiod");
   lock("cifsiod");

  *** DEADLOCK ***

  May be due to missing lock nesting notation

 2 locks held by kworker/0:2/78:
  #0:  ("cifsiod"){++++.+}, at: process_one_work+0x255/0x8e0
  #1:  ((&wdata->work)){+.+...}, at: process_one_work+0x255/0x8e0

 stack backtrace:
 CPU: 0 PID: 78 Comm: kworker/0:2 Not tainted 4.11.0+ #21
 Workqueue: cifsiod cifs_writev_complete
 Call Trace:
  dump_stack+0x85/0xc2
  __lock_acquire+0x17dd/0x2260
  ? match_held_lock+0x20/0x2b0
  ? trace_hardirqs_off_caller+0x86/0x130
  ? mark_lock+0xa6/0x920
  lock_acquire+0xcc/0x260
  ? lock_acquire+0xcc/0x260
  ? flush_work+0x215/0x350
  flush_work+0x236/0x350
  ? flush_work+0x215/0x350
  ? destroy_worker+0x170/0x170
  __cancel_work_timer+0x17d/0x210
  ? ___preempt_schedule+0x16/0x18
  cancel_work_sync+0x10/0x20
  cifsFileInfo_put+0x338/0x7f0
  cifs_writedata_release+0x2a/0x40
  ? cifs_writedata_release+0x2a/0x40
  cifs_writev_complete+0x29d/0x850
  ? preempt_count_sub+0x18/0xd0
  process_one_work+0x304/0x8e0
  worker_thread+0x9b/0x6a0
  kthread+0x1b2/0x200
  ? process_one_work+0x8e0/0x8e0
  ? kthread_create_on_node+0x40/0x40
  ret_from_fork+0x31/0x40

This is a real warning.  Since the oplock is queued on the same
workqueue this can deadlock if there is only one worker thread active
for the workqueue (which will be the case during memory pressure when
the rescuer thread is handling it).

Furthermore, there is at least one other kind of hang possible due to
the oplock break handling if there is only worker.  (This can be
reproduced without introducing memory pressure by having passing 1 for
the max_active parameter of cifsiod.) cifs_oplock_break() can wait
indefintely in the filemap_fdatawait() while the cifs_writev_complete()
work is blocked:

 sysrq: SysRq : Show Blocked State
   task                        PC stack   pid father
 kworker/0:1     D    0    16      2 0x00000000
 Workqueue: cifsiod cifs_oplock_break
 Call Trace:
  __schedule+0x562/0xf40
  ? mark_held_locks+0x4a/0xb0
  schedule+0x57/0xe0
  io_schedule+0x21/0x50
  wait_on_page_bit+0x143/0x190
  ? add_to_page_cache_lru+0x150/0x150
  __filemap_fdatawait_range+0x134/0x190
  ? do_writepages+0x51/0x70
  filemap_fdatawait_range+0x14/0x30
  filemap_fdatawait+0x3b/0x40
  cifs_oplock_break+0x651/0x710
  ? preempt_count_sub+0x18/0xd0
  process_one_work+0x304/0x8e0
  worker_thread+0x9b/0x6a0
  kthread+0x1b2/0x200
  ? process_one_work+0x8e0/0x8e0
  ? kthread_create_on_node+0x40/0x40
  ret_from_fork+0x31/0x40
 dd              D    0   683    171 0x00000000
 Call Trace:
  __schedule+0x562/0xf40
  ? mark_held_locks+0x29/0xb0
  schedule+0x57/0xe0
  io_schedule+0x21/0x50
  wait_on_page_bit+0x143/0x190
  ? add_to_page_cache_lru+0x150/0x150
  __filemap_fdatawait_range+0x134/0x190
  ? do_writepages+0x51/0x70
  filemap_fdatawait_range+0x14/0x30
  filemap_fdatawait+0x3b/0x40
  filemap_write_and_wait+0x4e/0x70
  cifs_flush+0x6a/0xb0
  filp_close+0x52/0xa0
  __close_fd+0xdc/0x150
  SyS_close+0x33/0x60
  entry_SYSCALL_64_fastpath+0x1f/0xbe

 Showing all locks held in the system:
 2 locks held by kworker/0:1/16:
  #0:  ("cifsiod"){.+.+.+}, at: process_one_work+0x255/0x8e0
  #1:  ((&cfile->oplock_break)){+.+.+.}, at: process_one_work+0x255/0x8e0

 Showing busy workqueues and worker pools:
 workqueue cifsiod: flags=0xc
   pwq 0: cpus=0 node=0 flags=0x0 nice=0 active=1/1
     in-flight: 16:cifs_oplock_break
     delayed: cifs_writev_complete, cifs_echo_request
 pool 0: cpus=0 node=0 flags=0x0 nice=0 hung=0s workers=3 idle: 750 3

Fix these problems by creating a a new workqueue (with a rescuer) for
the oplock break work.

Signed-off-by: Rabin Vincent 
Signed-off-by: Steve French 
Signed-off-by: Greg Kroah-Hartman

cifs: fix CIFS_ENUMERATE_SNAPSHOTS oops

2017-05-20T12:28:40+00:00

commit 6026685de33b0db5b2b6b0e9b41b3a1a3261033c upstream.

As with 618763958b22, an open directory may have a NULL private_data
pointer prior to readdir. CIFS_ENUMERATE_SNAPSHOTS must check for this
before dereference.

Fixes: 834170c85978 ("Enable previous version support")
Signed-off-by: David Disseldorp 
Signed-off-by: Steve French 
Signed-off-by: Greg Kroah-Hartman

cifs: fix leak in FSCTL_ENUM_SNAPS response handling

2017-05-20T12:28:40+00:00

commit 0e5c795592930d51fd30d53a2e7b73cba022a29b upstream.

The server may respond with success, and an output buffer less than
sizeof(struct smb_snapshot_array) in length. Do not leak the output
buffer in this case.

Fixes: 834170c85978 ("Enable previous version support")
Signed-off-by: David Disseldorp 
Signed-off-by: Steve French 
Signed-off-by: Greg Kroah-Hartman

CIFS: fix mapping of SFM_SPACE and SFM_PERIOD

2017-05-20T12:28:40+00:00

commit b704e70b7cf48f9b67c07d585168e102dfa30bb4 upstream.

- trailing space maps to 0xF028
- trailing period maps to 0xF029

This fix corrects the mapping of file names which have a trailing character
that would otherwise be illegal (period or space) but is allowed by POSIX.

Signed-off-by: Bjoern Jacke 
Signed-off-by: Steve French 
Signed-off-by: Greg Kroah-Hartman

SMB3: Work around mount failure when using SMB3 dialect to Macs

2017-05-20T12:28:40+00:00

commit 7db0a6efdc3e990cdfd4b24820d010e9eb7890ad upstream.

Macs send the maximum buffer size in response on ioctl to validate
negotiate security information, which causes us to fail the mount
as the response buffer is larger than the expected response.

Changed ioctl response processing to allow for padding of validate
negotiate ioctl response and limit the maximum response size to
maximum buffer size.

Signed-off-by: Steve French 
Signed-off-by: Greg Kroah-Hartman

Set unicode flag on cifs echo request to avoid Mac error

2017-05-20T12:28:40+00:00

commit 26c9cb668c7fbf9830516b75d8bee70b699ed449 upstream.

Mac requires the unicode flag to be set for cifs, even for the smb
echo request (which doesn't have strings).

Without this Mac rejects the periodic echo requests (when mounting
with cifs) that we use to check if server is down

Signed-off-by: Steve French 
Signed-off-by: Greg Kroah-Hartman

Fix match_prepath()

2017-05-20T12:28:39+00:00

commit cd8c42968ee651b69e00f8661caff32b0086e82d upstream.

Incorrect return value for shares not using the prefix path means that
we will never match superblocks for these shares.

Fixes: commit c1d8b24d1819 ("Compare prepaths when comparing superblocks")
Signed-off-by: Sachin Prabhu 
Reviewed-by: Pavel Shilovsky 
Signed-off-by: Steve French 
Signed-off-by: Greg Kroah-Hartman

Handle mismatched open calls

2017-05-08T05:47:55+00:00

commit 38bd49064a1ecb67baad33598e3d824448ab11ec upstream.

A signal can interrupt a SendReceive call which result in incoming
responses to the call being ignored. This is a problem for calls such as
open which results in the successful response being ignored. This
results in an open file resource on the server.

The patch looks into responses which were cancelled after being sent and
in case of successful open closes the open fids.

For this patch, the check is only done in SendReceive2()

RH-bz: 1403319

Signed-off-by: Sachin Prabhu 
Reviewed-by: Pavel Shilovsky 
Acked-by: Sachin Prabhu 
Signed-off-by: Pavel Shilovsky 
Signed-off-by: Greg Kroah-Hartman