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  1. 21 6月, 2017 5 次提交
  3. 13 5月, 2017 4 次提交
  5. 10 5月, 2017 2 次提交
    • S
      Don't delay freeing mids when blocked on slow socket write of request · de1892b8
      由 Steve French 提交于 
      When processing responses, and in particular freeing mids (DeleteMidQEntry),
which is very important since it also frees the associated buffers (cifs_buf_release),
we can block a long time if (writes to) socket is slow due to low memory or networking
issues.

We can block in send (smb request) waiting for memory, and be blocked in processing
responess (which could free memory if we let it) - since they both grab the
server->srv_mutex.

In practice, in the DeleteMidQEntry case - there is no reason we need to
grab the srv_mutex so remove these around DeleteMidQEntry, and it allows
us to free memory faster.
Signed-off-by: NSteve French <steve.french@primarydata.com>
Acked-by: NPavel Shilovsky <pshilov@microsoft.com>
      de1892b8
    • R
      CIFS: silence lockdep splat in cifs_relock_file() · 560d3889
      由 Rabin Vincent 提交于 
      cifs_relock_file() can perform a down_write() on the inode's lock_sem even
though it was already performed in cifs_strict_readv().  Lockdep complains
about this.  AFAICS, there is no problem here, and lockdep just needs to be
told that this nesting is OK.

 =============================================
 [ INFO: possible recursive locking detected ]
 4.11.0+ #20 Not tainted
 ---------------------------------------------
 cat/701 is trying to acquire lock:
  (&cifsi->lock_sem){++++.+}, at: cifs_reopen_file+0x7a7/0xc00

 but task is already holding lock:
  (&cifsi->lock_sem){++++.+}, at: cifs_strict_readv+0x177/0x310

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

        CPU0
        ----
   lock(&cifsi->lock_sem);
   lock(&cifsi->lock_sem);

  *** DEADLOCK ***

  May be due to missing lock nesting notation

 1 lock held by cat/701:
  #0:  (&cifsi->lock_sem){++++.+}, at: cifs_strict_readv+0x177/0x310

 stack backtrace:
 CPU: 0 PID: 701 Comm: cat Not tainted 4.11.0+ #20
 Call Trace:
  dump_stack+0x85/0xc2
  __lock_acquire+0x17dd/0x2260
  ? trace_hardirqs_on_thunk+0x1a/0x1c
  ? preempt_schedule_irq+0x6b/0x80
  lock_acquire+0xcc/0x260
  ? lock_acquire+0xcc/0x260
  ? cifs_reopen_file+0x7a7/0xc00
  down_read+0x2d/0x70
  ? cifs_reopen_file+0x7a7/0xc00
  cifs_reopen_file+0x7a7/0xc00
  ? printk+0x43/0x4b
  cifs_readpage_worker+0x327/0x8a0
  cifs_readpage+0x8c/0x2a0
  generic_file_read_iter+0x692/0xd00
  cifs_strict_readv+0x29f/0x310
  generic_file_splice_read+0x11c/0x1c0
  do_splice_to+0xa5/0xc0
  splice_direct_to_actor+0xfa/0x350
  ? generic_pipe_buf_nosteal+0x10/0x10
  do_splice_direct+0xb5/0xe0
  do_sendfile+0x278/0x3a0
  SyS_sendfile64+0xc4/0xe0
  entry_SYSCALL_64_fastpath+0x1f/0xbe
Signed-off-by: NRabin Vincent <rabinv@axis.com>
Acked-by: NPavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: NSteve French <smfrench@gmail.com>
      560d3889
  7. 09 5月, 2017 1 次提交
  9. 05 5月, 2017 1 次提交
  11. 04 5月, 2017 3 次提交
  13. 03 5月, 2017 9 次提交
    • R
      CIFS: fix oplock break deadlocks · 3998e6b8
      由 Rabin Vincent 提交于 
      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: NRabin Vincent <rabinv@axis.com>
Signed-off-by: NSteve French <smfrench@gmail.com>
CC: Stable <stable@vger.kernel.org>
      3998e6b8
    • D
      cifs: fix CIFS_ENUMERATE_SNAPSHOTS oops · 6026685d
      由 David Disseldorp 提交于 
      As with 61876395, an open directory may have a NULL private_data
pointer prior to readdir. CIFS_ENUMERATE_SNAPSHOTS must check for this
before dereference.

Fixes: 834170c8 ("Enable previous version support")
Signed-off-by: NDavid Disseldorp <ddiss@suse.de>
CC: Stable <stable@vger.kernel.org>
Signed-off-by: NSteve French <smfrench@gmail.com>
      6026685d
    • D
      cifs: fix leak in FSCTL_ENUM_SNAPS response handling · 0e5c7955
      由 David Disseldorp 提交于 
      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: 834170c8 ("Enable previous version support")
Signed-off-by: NDavid Disseldorp <ddiss@suse.de>
CC: Stable <stable@vger.kernel.org>
Signed-off-by: NSteve French <smfrench@gmail.com>
      0e5c7955
    • S
      Set unicode flag on cifs echo request to avoid Mac error · 26c9cb66
      由 Steve French 提交于 
      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: NSteve French <smfrench@gmail.com>
CC: Stable <stable@vger.kernel.org>
      26c9cb66
    • P
      CIFS: Add asynchronous write support through kernel AIO · c610c4b6
      由 Pavel Shilovsky 提交于 
      This patch adds support to process write calls passed by io_submit()
asynchronously. It based on the previously introduced async context
that allows to process i/o responses in a separate thread and
return the caller immediately for asynchronous calls.

This improves writing performance of single threaded applications
with increasing of i/o queue depth size.
Signed-off-by: NPavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: NSteve French <smfrench@gmail.com>
      c610c4b6
    • P
      CIFS: Add asynchronous read support through kernel AIO · 6685c5e2
      由 Pavel Shilovsky 提交于 
      This patch adds support to process read calls passed by io_submit()
asynchronously. It based on the previously introduced async context
that allows to process i/o responses in a separate thread and
return the caller immediately for asynchronous calls.

This improves reading performance of single threaded applications
with increasing of i/o queue depth size.
Signed-off-by: NPavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: NSteve French <smfrench@gmail.com>
      6685c5e2
    • P
      CIFS: Add asynchronous context to support kernel AIO · ccf7f408
      由 Pavel Shilovsky 提交于 
      Currently the code doesn't recognize asynchronous calls passed
by io_submit() and processes all calls synchronously. This is not
what kernel AIO expects. This patch introduces a new async context
that keeps track of all issued i/o requests and moves a response
collecting procedure to a separate thread. This allows to return
to a caller immediately for async calls and call iocb->ki_complete()
once all requests are completed. For sync calls the current thread
simply waits until all requests are completed.
Signed-off-by: NPavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: NSteve French <smfrench@gmail.com>
      ccf7f408
    • D
      cifs: fix IPv6 link local, with scope id, address parsing · 29bb3158
      由 Daniel N Pettersson 提交于 
      When the IP address is gotten from the UNC, use only the address part
of the UNC. Else all after the percent sign in an IPv6 link local
address is interpreted as a scope id. This includes the slash and
share name. A scope id is expected to be an integer and any trailing
characters makes the conversion to integer fail.
Example of mount command that fails:
mount -i -t cifs //fe80::6a05:caff:fe3e:8ffc%2/test /mnt/t -o sec=none
Signed-off-by: NDaniel N Pettersson <danielnp@axis.com>
Signed-off-by: NSteve French <smfrench@gmail.com>
      29bb3158
    • D
      cifs: small underflow in cnvrtDosUnixTm() · 564277ec
      由 Dan Carpenter 提交于 
      January is month 1.  There is no zero-th month.  If someone passes a
zero month then it means we read from one space before the start of the
total_days_of_prev_months[] array.

We may as well also be strict about days as well.

Fixes: 1bd5bbcb ("[CIFS] Legacy time handling for Win9x and OS/2 part 1")
Signed-off-by: NDan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: NSteve French <smfrench@gmail.com>
      564277ec
  15. 28 4月, 2017 3 次提交
  17. 21 4月, 2017 1 次提交
  19. 18 4月, 2017 1 次提交
    • S
      cifs: Do not send echoes before Negotiate is complete · 62a6cfdd
      由 Sachin Prabhu 提交于 
      commit 4fcd1813 ("Fix reconnect to not defer smb3 session reconnect
long after socket reconnect") added support for Negotiate requests to
be initiated by echo calls.

To avoid delays in calling echo after a reconnect, I added the patch
introduced by the commit b8c60012 ("Call echo service immediately
after socket reconnect").

This has however caused a regression with cifs shares which do not have
support for echo calls to trigger Negotiate requests. On connections
which need to call Negotiation, the echo calls trigger an error which
triggers a reconnect which in turn triggers another echo call. This
results in a loop which is only broken when an operation is performed on
the cifs share. For an idle share, it can DOS a server.

The patch uses the smb_operation can_echo() for cifs so that it is
called only if connection has been already been setup.

kernel bz: 194531
Signed-off-by: NSachin Prabhu <sprabhu@redhat.com>
Tested-by: NJonathan Liu <net147@gmail.com>
Acked-by: NPavel Shilovsky <pshilov@microsoft.com>
CC: Stable <stable@vger.kernel.org>
Signed-off-by: NSteve French <smfrench@gmail.com>
      62a6cfdd
  21. 13 4月, 2017 1 次提交
    • P
      CIFS: Fix SMB3 mount without specifying a security mechanism · 67dbea2c
      由 Pavel Shilovsky 提交于 
      Commit ef65aaed ("smb2: Enforce sec= mount option") changed the
behavior of a mount command to enforce a specified security mechanism
during mounting. On another hand according to the spec if SMB3 server
doesn't respond with a security context it implies that it supports
NTLMSSP. The current code doesn't keep it in mind and fails a mount
for such servers if no security mechanism is specified. Fix this by
indicating that a server supports NTLMSSP if a security context isn't
returned during negotiate phase. This allows the code to use NTLMSSP
by default for SMB3 mounts.
Signed-off-by: NPavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: NSteve French <smfrench@gmail.com>
      67dbea2c
  23. 11 4月, 2017 5 次提交
    • G
      CIFS: store results of cifs_reopen_file to avoid infinite wait · 1fa839b4
      由 Germano Percossi 提交于 
      This fixes Continuous Availability when errors during
file reopen are encountered.

cifs_user_readv and cifs_user_writev would wait for ever if
results of cifs_reopen_file are not stored and for later inspection.

In fact, results are checked and, in case of errors, a chain
of function calls leading to reads and writes to be scheduled in
a separate thread is skipped.
These threads will wake up the corresponding waiters once reads
and writes are done.

However, given the return value is not stored, when rc is checked
for errors a previous one (always zero) is inspected instead.
This leads to pending reads/writes added to the list, making
cifs_user_readv and cifs_user_writev wait for ever.
Signed-off-by: NGermano Percossi <germano.percossi@citrix.com>
Reviewed-by: NPavel Shilovsky <pshilov@microsoft.com>
CC: Stable <stable@vger.kernel.org>
Signed-off-by: NSteve French <smfrench@gmail.com>
      1fa839b4
    • G
      CIFS: remove bad_network_name flag · a0918f1c
      由 Germano Percossi 提交于 
      STATUS_BAD_NETWORK_NAME can be received during node failover,
causing the flag to be set and making the reconnect thread
always unsuccessful, thereafter.

Once the only place where it is set is removed, the remaining
bits are rendered moot.

Removing it does not prevent "mount" from failing when a non
existent share is passed.

What happens when the share really ceases to exist while the
share is mounted is undefined now as much as it was before.
Signed-off-by: NGermano Percossi <germano.percossi@citrix.com>
Reviewed-by: NPavel Shilovsky <pshilov@microsoft.com>
CC: Stable <stable@vger.kernel.org>
Signed-off-by: NSteve French <smfrench@gmail.com>
      a0918f1c
    • G
      CIFS: reconnect thread reschedule itself · 18ea4311
      由 Germano Percossi 提交于 
      In case of error, smb2_reconnect_server reschedule itself
with a delay, to avoid being too aggressive.
Signed-off-by: NGermano Percossi <germano.percossi@citrix.com>
Reviewed-by: NPavel Shilovsky <pshilov@microsoft.com>
CC: Stable <stable@vger.kernel.org>
Signed-off-by: NSteve French <smfrench@gmail.com>
      18ea4311
    • M
      CIFS: handle guest access errors to Windows shares · 40920c2b
      由 Mark Syms 提交于 
      Commit 1a967d6c ("correctly to
anonymous authentication for the NTLM(v2) authentication") introduces
a regression in handling errors related to attempting a guest
connection to a Windows share which requires authentication. This
should result in a permission denied error but actually causes the
kernel module to enter a never-ending loop trying to follow a DFS
referal which doesn't exist.

The base cause of this is the failure now occurs later in the process
during tree connect and not at the session setup setup and all errors
in tree connect are interpreted as needing to follow the DFS paths
which isn't in this case correct. So, check the returned error against
EACCES and fail if this is returned error.

Feedback from Aurelien:

  PS> net user guest /activate:no
    PS> mkdir C:\guestshare
      PS> icacls C:\guestshare /grant 'Everyone:(OI)(CI)F'
        PS> new-smbshare -name guestshare -path C:\guestshare -fullaccess Everyone

        I've tested v3.10, v4.4, master, master+your patch using default options
        (empty or no user "NU") and user=abc (U).

        NT_LOGON_FAILURE in session setup: LF
        This is what you seem to have in 3.10.

        NT_ACCESS_DENIED in tree connect to the share: AD
        This is what you get before your infinite loop.

                     |   NU       U
                     --------------------------------
                     3.10         |   LF       LF
                     4.4          |   LF       LF
                     master       |   AD       LF
                     master+patch |   AD       LF

                     No infinite DFS loop :(
                     All these issues result in mount failing very fast with permission denied.

                     I guess it could be from either the Windows version or the share/folder
                     ACL. A deeper analysis of the packets might reveal more.

                     In any case I did not notice any issues for on a basic DFS setup with
                     the patch so I don't think it introduced any regressions, which is
                     probably all that matters. It still bothers me a little I couldn't hit
                     the bug.

                     I've included kernel output w/ debugging output and network capture of
                     my tests if anyone want to have a look at it. (master+patch = ml-guestfix).
Signed-off-by: NMark Syms <mark.syms@citrix.com>
Reviewed-by: NAurelien Aptel <aaptel@suse.com>
Tested-by: NAurelien Aptel <aaptel@suse.com>
Acked-by: NPavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: NSteve French <smfrench@gmail.com>
      40920c2b
    • P
      CIFS: Fix null pointer deref during read resp processing · 350be257
      由 Pavel Shilovsky 提交于 
      Currently during receiving a read response mid->resp_buf can be
NULL when it is being passed to cifs_discard_remaining_data() from
cifs_readv_discard(). Fix it by always passing server->smallbuf
instead and initializing mid->resp_buf at the end of read response
processing.
Signed-off-by: NPavel Shilovsky <pshilov@microsoft.com>
CC: Stable <stable@vger.kernel.org>
Acked-by: NSachin Prabhu <sprabhu@redhat.com>
Signed-off-by: NSteve French <smfrench@gmail.com>
      350be257
  25. 07 4月, 2017 4 次提交