As per MS-DFSC, when a DFS cache entry is expired and it is a DFS
link, then a new DFS referral must be sent to root server in order to
refresh the expired entry.

This patch ensures that all new DFS referrals for refreshing the cache
are sent to DFS root.
Signed-off-by: NPaulo Alcantara (SUSE) <paulo@paulo.ac>
Signed-off-by: NSteve French <stfrench@microsoft.com>

A trivial patch.

cpu_to_le32() is capable enough to detect __builtin_constant_p()
and to use an appropriate compile time ___constant_swahb32()
function.

So we can use cpu_to_le32() instead of __constant_cpu_to_le32().
Signed-off-by: NSergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: NSteve French <stfrench@microsoft.com>

Also track minimum and maximum time by command in /proc/fs/cifs/Stats
Signed-off-by: NSteve French <stfrench@microsoft.com>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

The flags field in 'struct shash_desc' never actually does anything.
The only ostensibly supported flag is CRYPTO_TFM_REQ_MAY_SLEEP.
However, no shash algorithm ever sleeps, making this flag a no-op.

With this being the case, inevitably some users who can't sleep wrongly
pass MAY_SLEEP.  These would all need to be fixed if any shash algorithm
actually started sleeping.  For example, the shash_ahash_*() functions,
which wrap a shash algorithm with the ahash API, pass through MAY_SLEEP
from the ahash API to the shash API.  However, the shash functions are
called under kmap_atomic(), so actually they're assumed to never sleep.

Even if it turns out that some users do need preemption points while
hashing large buffers, we could easily provide a helper function
crypto_shash_update_large() which divides the data into smaller chunks
and calls crypto_shash_update() and cond_resched() for each chunk.  It's
not necessary to have a flag in 'struct shash_desc', nor is it necessary
to make individual shash algorithms aware of this at all.

Therefore, remove shash_desc::flags, and document that the
crypto_shash_*() functions can be called from any context.
Signed-off-by: NEric Biggers <ebiggers@google.com>
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>

CIFS can leak pages reference gotten through GUP (get_user_pages*()
through iov_iter_get_pages()). This happen if cifs_send_async_read()
or cifs_write_from_iter() calls fail from within __cifs_readv() and
__cifs_writev() respectively. This patch move page unreference to
cifs_aio_ctx_release() which will happens on all code paths this is
all simpler to follow for correctness.
Signed-off-by: NJérôme Glisse <jglisse@redhat.com>
Cc: Steve French <sfrench@samba.org>
Cc: linux-cifs@vger.kernel.org
Cc: samba-technical@lists.samba.org
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Stable <stable@vger.kernel.org>
Signed-off-by: NSteve French <stfrench@microsoft.com>
Reviewed-by: NPavel Shilovsky <pshilov@microsoft.com>

A path-based rename returning EBUSY will incorrectly try opening
the file with a cifs (NT Create AndX) operation on an smb2+ mount,
which causes the server to force a session close.

If the mount is smb2+, skip the fallback.
Signed-off-by: NFrank Sorenson <sorenson@redhat.com>
Signed-off-by: NSteve French <stfrench@microsoft.com>
CC: Stable <stable@vger.kernel.org>
Reviewed-by: NRonnie Sahlberg <lsahlber@redhat.com>

Commit 088aaf17 introduced a leak where
if SMB2_read() returned an error we would return without freeing the
request buffer.

Cc: Stable <stable@vger.kernel.org>
Signed-off-by: NRonnie Sahlberg <lsahlber@redhat.com>
Reviewed-by: NPavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: NSteve French <stfrench@microsoft.com>

In the oplock break handler, writing pending changes from pages puts
the FileInfo handle. If the refcount reaches zero it closes the handle
and waits for any oplock break handler to return, thus causing a deadlock.

To prevent this situation:

* We add a wait flag to cifsFileInfo_put() to decide whether we should
  wait for running/pending oplock break handlers

* We keep an additionnal reference of the SMB FileInfo handle so that
  for the rest of the handler putting the handle won't close it.
  - The ref is bumped everytime we queue the handler via the
    cifs_queue_oplock_break() helper.
  - The ref is decremented at the end of the handler

This bug was triggered by xfstest 464.

Also important fix to address the various reports of
oops in smb2_push_mandatory_locks
Signed-off-by: NAurelien Aptel <aaptel@suse.com>
Signed-off-by: NSteve French <stfrench@microsoft.com>
Reviewed-by: NPavel Shilovsky <pshilov@microsoft.com>
CC: Stable <stable@vger.kernel.org>

If we enter smb2_query_symlink() for something that is not a symlink
and where the SMB2_open() would succeed we would never end up
closing this handle and would thus leak a handle on the server.

Fix this by immediately calling SMB2_close() on successfull open.
Signed-off-by: NRonnie Sahlberg <lsahlber@redhat.com>
CC: Stable <stable@vger.kernel.org>
Signed-off-by: NSteve French <stfrench@microsoft.com>
Reviewed-by: NPavel Shilovsky <pshilov@microsoft.com>

There is a KASAN slab-out-of-bounds:
BUG: KASAN: slab-out-of-bounds in _copy_from_iter_full+0x783/0xaa0
Read of size 80 at addr ffff88810c35e180 by task mount.cifs/539

CPU: 1 PID: 539 Comm: mount.cifs Not tainted 4.19 #10
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS
            rel-1.12.0-0-ga698c8995f-prebuilt.qemu.org 04/01/2014
Call Trace:
 dump_stack+0xdd/0x12a
 print_address_description+0xa7/0x540
 kasan_report+0x1ff/0x550
 check_memory_region+0x2f1/0x310
 memcpy+0x2f/0x80
 _copy_from_iter_full+0x783/0xaa0
 tcp_sendmsg_locked+0x1840/0x4140
 tcp_sendmsg+0x37/0x60
 inet_sendmsg+0x18c/0x490
 sock_sendmsg+0xae/0x130
 smb_send_kvec+0x29c/0x520
 __smb_send_rqst+0x3ef/0xc60
 smb_send_rqst+0x25a/0x2e0
 compound_send_recv+0x9e8/0x2af0
 cifs_send_recv+0x24/0x30
 SMB2_open+0x35e/0x1620
 open_shroot+0x27b/0x490
 smb2_open_op_close+0x4e1/0x590
 smb2_query_path_info+0x2ac/0x650
 cifs_get_inode_info+0x1058/0x28f0
 cifs_root_iget+0x3bb/0xf80
 cifs_smb3_do_mount+0xe00/0x14c0
 cifs_do_mount+0x15/0x20
 mount_fs+0x5e/0x290
 vfs_kern_mount+0x88/0x460
 do_mount+0x398/0x31e0
 ksys_mount+0xc6/0x150
 __x64_sys_mount+0xea/0x190
 do_syscall_64+0x122/0x590
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

It can be reproduced by the following step:
  1. samba configured with: server max protocol = SMB2_10
  2. mount -o vers=default

When parse the mount version parameter, the 'ops' and 'vals'
was setted to smb30,  if negotiate result is smb21, just
update the 'ops' to smb21, but the 'vals' is still smb30.
When add lease context, the iov_base is allocated with smb21
ops, but the iov_len is initiallited with the smb30. Because
the iov_len is longer than iov_base, when send the message,
copy array out of bounds.

we need to keep the 'ops' and 'vals' consistent.

Fixes: 9764c02f ("SMB3: Add support for multidialect negotiate (SMB2.1 and later)")
Fixes: d5c7076b ("smb3: add smb3.1.1 to default dialect list")
Signed-off-by: NZhangXiaoxu <zhangxiaoxu5@huawei.com>
Signed-off-by: NSteve French <stfrench@microsoft.com>
CC: Stable <stable@vger.kernel.org>
Reviewed-by: NPavel Shilovsky <pshilov@microsoft.com>

There is a KASAN use-after-free:
BUG: KASAN: use-after-free in SMB2_read+0x1136/0x1190
Read of size 8 at addr ffff8880b4e45e50 by task ln/1009

Should not release the 'req' because it will use in the trace.

Fixes: eccb4422 ("smb3: Add ftrace tracepoints for improved SMB3 debugging")
Signed-off-by: NZhangXiaoxu <zhangxiaoxu5@huawei.com>
Signed-off-by: NSteve French <stfrench@microsoft.com>
CC: Stable <stable@vger.kernel.org> 4.18+
Reviewed-by: NPavel Shilovsky <pshilov@microsoft.com>

There is a KASAN use-after-free:
BUG: KASAN: use-after-free in SMB2_write+0x1342/0x1580
Read of size 8 at addr ffff8880b6a8e450 by task ln/4196

Should not release the 'req' because it will use in the trace.

Fixes: eccb4422 ("smb3: Add ftrace tracepoints for improved SMB3 debugging")
Signed-off-by: NZhangXiaoxu <zhangxiaoxu5@huawei.com>
Signed-off-by: NSteve French <stfrench@microsoft.com>
CC: Stable <stable@vger.kernel.org> 4.18+
Reviewed-by: NPavel Shilovsky <pshilov@microsoft.com>

It only means that we do not have a valid cached value for the
file_all_info structure.

CC: Stable <stable@vger.kernel.org>
Signed-off-by: NRonnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: NSteve French <stfrench@microsoft.com>
Reviewed-by: NPavel Shilovsky <pshilov@microsoft.com>

Reconnecting after server or network failure can be improved
(to maintain availability and protect data integrity) by allowing
the client to choose the default persistent (or resilient)
handle timeout in some use cases.  Today we default to 0 which lets
the server pick the default timeout (usually 120 seconds) but this
can be problematic for some workloads.  Add the new mount parameter
to cifs.ko for SMB3 mounts "handletimeout" which enables the user
to override the default handle timeout for persistent (mount
option "persistenthandles") or resilient handles (mount option
"resilienthandles").  Maximum allowed is 16 minutes (960000 ms).
Units for the timeout are expressed in milliseconds. See
section 2.2.14.2.12 and 2.2.31.3 of the MS-SMB2 protocol
specification for more information.
Signed-off-by: NSteve French <stfrench@microsoft.com>
Reviewed-by: NPavel Shilovsky <pshilov@microsoft.com>
Reviewed-by: NRonnie Sahlberg <lsahlber@redhat.com>
CC: Stable <stable@vger.kernel.org>

Some servers (see MS-SMB2 protocol specification
section 3.3.5.15.1) expect that the FSCTL enumerate snapshots
is done twice, with the first query having EXACTLY the minimum
size response buffer requested (16 bytes) which refreshes
the snapshot list (otherwise that and subsequent queries get
an empty list returned).  So had to add code to set
the maximum response size differently for the first snapshot
query (which gets the size needed for the second query which
contains the actual list of snapshots).
Signed-off-by: NSteve French <stfrench@microsoft.com>
Reviewed-by: NRonnie Sahlberg <lsahlber@redhat.com>
Reviewed-by: NPavel Shilovsky <pshilov@microsoft.com>
CC: Stable <stable@vger.kernel.org> # 4.19+

Fix a bug where we used to not initialize the cached fid structure at all
in open_shroot() if the open was successful but we did not get a lease.
This would leave the structure uninitialized and later when we close the handle
we would in close_shroot() try to kref_put() an uninitialized refcount.

Fix this by always initializing this structure if the open was successful
but only do the extra get() if we got a lease.
This extra get() is only used to hold the structure until we get a lease
break from the server at which point we will kref_put() it during lease
processing.
Signed-off-by: NRonnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: NSteve French <stfrench@microsoft.com>
CC: Stable <stable@vger.kernel.org>

To 2.19
Signed-off-by: NSteve French <stfrench@microsoft.com>

Workaround problem with Samba responses to SMB3.1.1
null user (guest) mounts.  The server doesn't set the
expected flag in the session setup response so we have
to do a similar check to what is done in smb3_validate_negotiate
where we also check if the user is a null user (but not sec=krb5
since username might not be passed in on mount for Kerberos case).

Note that the commit below tightened the conditions and forced signing
for the SMB2-TreeConnect commands as per MS-SMB2.
However, this should only apply to normal user sessions and not for
cases where there is no user (even if server forgets to set the flag
in the response) since we don't have anything useful to sign with.
This is especially important now that the more secure SMB3.1.1 protocol
is in the default dialect list.

An earlier patch ("cifs: allow guest mounts to work for smb3.11") fixed
the guest mounts to Windows.

    Fixes: 6188f28b ("Tree connect for SMB3.1.1 must be signed for non-encrypted shares")
Reviewed-by: NRonnie Sahlberg <lsahlber@redhat.com>
Reviewed-by: NPaulo Alcantara <palcantara@suse.de>
CC: Stable <stable@vger.kernel.org>
Signed-off-by: NSteve French <stfrench@microsoft.com>

This patch fixes the following KASAN report:

[  779.044746] BUG: KASAN: slab-out-of-bounds in string+0xab/0x180
[  779.044750] Read of size 1 at addr ffff88814f327968 by task trace-cmd/2812

[  779.044756] CPU: 1 PID: 2812 Comm: trace-cmd Not tainted 5.1.0-rc1+ #62
[  779.044760] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.12.0-0-ga698c89-prebuilt.qemu.org 04/01/2014
[  779.044761] Call Trace:
[  779.044769]  dump_stack+0x5b/0x90
[  779.044775]  ? string+0xab/0x180
[  779.044781]  print_address_description+0x6c/0x23c
[  779.044787]  ? string+0xab/0x180
[  779.044792]  ? string+0xab/0x180
[  779.044797]  kasan_report.cold.3+0x1a/0x32
[  779.044803]  ? string+0xab/0x180
[  779.044809]  string+0xab/0x180
[  779.044816]  ? widen_string+0x160/0x160
[  779.044822]  ? vsnprintf+0x5bf/0x7f0
[  779.044829]  vsnprintf+0x4e7/0x7f0
[  779.044836]  ? pointer+0x4a0/0x4a0
[  779.044841]  ? seq_buf_vprintf+0x79/0xc0
[  779.044848]  seq_buf_vprintf+0x62/0xc0
[  779.044855]  trace_seq_printf+0x113/0x210
[  779.044861]  ? trace_seq_puts+0x110/0x110
[  779.044867]  ? trace_raw_output_prep+0xd8/0x110
[  779.044876]  trace_raw_output_smb3_tcon_class+0x9f/0xc0
[  779.044882]  print_trace_line+0x377/0x890
[  779.044888]  ? tracing_buffers_read+0x300/0x300
[  779.044893]  ? ring_buffer_read+0x58/0x70
[  779.044899]  s_show+0x6e/0x140
[  779.044906]  seq_read+0x505/0x6a0
[  779.044913]  vfs_read+0xaf/0x1b0
[  779.044919]  ksys_read+0xa1/0x130
[  779.044925]  ? kernel_write+0xa0/0xa0
[  779.044931]  ? __do_page_fault+0x3d5/0x620
[  779.044938]  do_syscall_64+0x63/0x150
[  779.044944]  entry_SYSCALL_64_after_hwframe+0x44/0xa9
[  779.044949] RIP: 0033:0x7f62c2c2db31
[ 779.044955] Code: fe ff ff 48 8d 3d 17 9e 09 00 48 83 ec 08 e8 96 02
02 00 66 0f 1f 44 00 00 8b 05 fa fc 2c 00 48 63 ff 85 c0 75 13 31 c0
0f 05 <48> 3d 00 f0 ff ff 77 57 f3 c3 0f 1f 44 00 00 55 53 48 89 d5 48
89
[  779.044958] RSP: 002b:00007ffd6e116678 EFLAGS: 00000246 ORIG_RAX: 0000000000000000
[  779.044964] RAX: ffffffffffffffda RBX: 0000560a38be9260 RCX: 00007f62c2c2db31
[  779.044966] RDX: 0000000000002000 RSI: 00007ffd6e116710 RDI: 0000000000000003
[  779.044966] RDX: 0000000000002000 RSI: 00007ffd6e116710 RDI: 0000000000000003
[  779.044969] RBP: 00007f62c2ef5420 R08: 0000000000000000 R09: 0000000000000003
[  779.044972] R10: ffffffffffffffa8 R11: 0000000000000246 R12: 00007ffd6e116710
[  779.044975] R13: 0000000000002000 R14: 0000000000000d68 R15: 0000000000002000

[  779.044981] Allocated by task 1257:
[  779.044987]  __kasan_kmalloc.constprop.5+0xc1/0xd0
[  779.044992]  kmem_cache_alloc+0xad/0x1a0
[  779.044997]  getname_flags+0x6c/0x2a0
[  779.045003]  user_path_at_empty+0x1d/0x40
[  779.045008]  do_faccessat+0x12a/0x330
[  779.045012]  do_syscall_64+0x63/0x150
[  779.045017]  entry_SYSCALL_64_after_hwframe+0x44/0xa9

[  779.045019] Freed by task 1257:
[  779.045023]  __kasan_slab_free+0x12e/0x180
[  779.045029]  kmem_cache_free+0x85/0x1b0
[  779.045034]  filename_lookup.part.70+0x176/0x250
[  779.045039]  do_faccessat+0x12a/0x330
[  779.045043]  do_syscall_64+0x63/0x150
[  779.045048]  entry_SYSCALL_64_after_hwframe+0x44/0xa9

[  779.045052] The buggy address belongs to the object at ffff88814f326600
which belongs to the cache names_cache of size 4096
[  779.045057] The buggy address is located 872 bytes to the right of
4096-byte region [ffff88814f326600, ffff88814f327600)
[  779.045058] The buggy address belongs to the page:
[  779.045062] page:ffffea00053cc800 count:1 mapcount:0 mapping:ffff88815b191b40 index:0x0 compound_mapcount: 0
[  779.045067] flags: 0x200000000010200(slab|head)
[  779.045075] raw: 0200000000010200 dead000000000100 dead000000000200 ffff88815b191b40
[  779.045081] raw: 0000000000000000 0000000000070007 00000001ffffffff 0000000000000000
[  779.045083] page dumped because: kasan: bad access detected

[  779.045085] Memory state around the buggy address:
[  779.045089]  ffff88814f327800: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[  779.045093]  ffff88814f327880: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[  779.045097] >ffff88814f327900: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[  779.045099]                                                           ^
[  779.045103]  ffff88814f327980: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[  779.045107]  ffff88814f327a00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[  779.045109] ==================================================================
[  779.045110] Disabling lock debugging due to kernel taint

Correctly assign tree name str for smb3_tcon event.
Signed-off-by: NPaulo Alcantara (SUSE) <paulo@paulo.ac>
Signed-off-by: NSteve French <stfrench@microsoft.com>

Fix Guest/Anonymous sessions so that they work with SMB 3.11.

The commit noted below tightened the conditions and forced signing for
the SMB2-TreeConnect commands as per MS-SMB2.
However, this should only apply to normal user sessions and not for
Guest/Anonumous sessions.

Fixes: 6188f28b ("Tree connect for SMB3.1.1 must be signed for non-encrypted shares")
Signed-off-by: NRonnie Sahlberg <lsahlber@redhat.com>
CC: Stable <stable@vger.kernel.org>
Signed-off-by: NSteve French <stfrench@microsoft.com>

It was mapped to EIO which can be confusing when user space
queries for an object GUID for an object for which the server
file system doesn't support (or hasn't saved one).

As Amir Goldstein suggested this is similar to ENOATTR
(equivalently ENODATA in Linux errno definitions) so
changing NT STATUS code mapping for OBJECTID_NOT_FOUND
to ENODATA.
Signed-off-by: NSteve French <stfrench@microsoft.com>
CC: Amir Goldstein <amir73il@gmail.com>

dedupe_file_range operations is combiled into remap_file_range.
But it's always skipped for dedupe operations in function
cifs_remap_file_range.

Example to test:
Before this patch:
  # dd if=/dev/zero of=cifs/file bs=1M count=1
  # xfs_io -c "dedupe cifs/file 4k 64k 4k" cifs/file
  XFS_IOC_FILE_EXTENT_SAME: Invalid argument

After this patch:
  # dd if=/dev/zero of=cifs/file bs=1M count=1
  # xfs_io -c "dedupe cifs/file 4k 64k 4k" cifs/file
  XFS_IOC_FILE_EXTENT_SAME: Operation not supported

Influence for xfstests:
generic/091
generic/112
generic/127
generic/263
These tests report this error "do_copy_range:: Invalid
argument" instead of "FIDEDUPERANGE: Invalid argument".
Because there are still two bugs cause these test failed.
https://bugzilla.kernel.org/show_bug.cgi?id=202935
https://bugzilla.kernel.org/show_bug.cgi?id=202785Signed-off-by: NXiaoli Feng <fengxiaoli0714@gmail.com>
Signed-off-by: NSteve French <stfrench@microsoft.com>

When sending a rdata, transport may return -EAGAIN. In this case
we should re-obtain credits because the session may have been
reconnected.

Change in v2: adjust_credits before re-sending
Signed-off-by: NLong Li <longli@microsoft.com>
Signed-off-by: NSteve French <stfrench@microsoft.com>
Reviewed-by: NPavel Shilovsky <pshilov@microsoft.com>

When sending a wdata, transport may return -EAGAIN. In this case
we should re-obtain credits because the session may have been
reconnected.

Change in v2: adjust_credits before re-sending
Signed-off-by: NLong Li <longli@microsoft.com>
Signed-off-by: NSteve French <stfrench@microsoft.com>
Reviewed-by: NPavel Shilovsky <pshilov@microsoft.com>

We have a customer reporting crashes in lock_get_status() with many
"Leaked POSIX lock" messages preceeding the crash.

 Leaked POSIX lock on dev=0x0:0x56 ...
 Leaked POSIX lock on dev=0x0:0x56 ...
 Leaked POSIX lock on dev=0x0:0x56 ...
 Leaked POSIX lock on dev=0x0:0x53 ...
 Leaked POSIX lock on dev=0x0:0x53 ...
 Leaked POSIX lock on dev=0x0:0x53 ...
 Leaked POSIX lock on dev=0x0:0x53 ...
 POSIX: fl_owner=ffff8900e7b79380 fl_flags=0x1 fl_type=0x1 fl_pid=20709
 Leaked POSIX lock on dev=0x0:0x4b ino...
 Leaked locks on dev=0x0:0x4b ino=0xf911400000029:
 POSIX: fl_owner=ffff89f41c870e00 fl_flags=0x1 fl_type=0x1 fl_pid=19592
 stack segment: 0000 [#1] SMP
 Modules linked in: binfmt_misc msr tcp_diag udp_diag inet_diag unix_diag af_packet_diag netlink_diag rpcsec_gss_krb5 arc4 ecb auth_rpcgss nfsv4 md4 nfs nls_utf8 lockd grace cifs sunrpc ccm dns_resolver fscache af_packet iscsi_ibft iscsi_boot_sysfs vmw_vsock_vmci_transport vsock xfs libcrc32c sb_edac edac_core crct10dif_pclmul crc32_pclmul ghash_clmulni_intel drbg ansi_cprng vmw_balloon aesni_intel aes_x86_64 lrw gf128mul glue_helper ablk_helper cryptd joydev pcspkr vmxnet3 i2c_piix4 vmw_vmci shpchp fjes processor button ac btrfs xor raid6_pq sr_mod cdrom ata_generic sd_mod ata_piix vmwgfx crc32c_intel drm_kms_helper syscopyarea sysfillrect sysimgblt fb_sys_fops ttm serio_raw ahci libahci drm libata vmw_pvscsi sg dm_multipath dm_mod scsi_dh_rdac scsi_dh_emc scsi_dh_alua scsi_mod autofs4

 Supported: Yes
 CPU: 6 PID: 28250 Comm: lsof Not tainted 4.4.156-94.64-default #1
 Hardware name: VMware, Inc. VMware Virtual Platform/440BX Desktop Reference Platform, BIOS 6.00 04/05/2016
 task: ffff88a345f28740 ti: ffff88c74005c000 task.ti: ffff88c74005c000
 RIP: 0010:[<ffffffff8125dcab>]  [<ffffffff8125dcab>] lock_get_status+0x9b/0x3b0
 RSP: 0018:ffff88c74005fd90  EFLAGS: 00010202
 RAX: ffff89bde83e20ae RBX: ffff89e870003d18 RCX: 0000000049534f50
 RDX: ffffffff81a3541f RSI: ffffffff81a3544e RDI: ffff89bde83e20ae
 RBP: 0026252423222120 R08: 0000000020584953 R09: 000000000000ffff
 R10: 0000000000000000 R11: ffff88c74005fc70 R12: ffff89e5ca7b1340
 R13: 00000000000050e5 R14: ffff89e870003d30 R15: ffff89e5ca7b1340
 FS:  00007fafd64be800(0000) GS:ffff89f41fd00000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: 0000000001c80018 CR3: 000000a522048000 CR4: 0000000000360670
 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
 Stack:
  0000000000000208 ffffffff81a3d6b6 ffff89e870003d30 ffff89e870003d18
  ffff89e5ca7b1340 ffff89f41738d7c0 ffff89e870003d30 ffff89e5ca7b1340
  ffffffff8125e08f 0000000000000000 ffff89bc22b67d00 ffff88c74005ff28
 Call Trace:
  [<ffffffff8125e08f>] locks_show+0x2f/0x70
  [<ffffffff81230ad1>] seq_read+0x251/0x3a0
  [<ffffffff81275bbc>] proc_reg_read+0x3c/0x70
  [<ffffffff8120e456>] __vfs_read+0x26/0x140
  [<ffffffff8120e9da>] vfs_read+0x7a/0x120
  [<ffffffff8120faf2>] SyS_read+0x42/0xa0
  [<ffffffff8161cbc3>] entry_SYSCALL_64_fastpath+0x1e/0xb7

When Linux closes a FD (close(), close-on-exec, dup2(), ...) it calls
filp_close() which also removes all posix locks.

The lock struct is initialized like so in filp_close() and passed
down to cifs

	...
        lock.fl_type = F_UNLCK;
        lock.fl_flags = FL_POSIX | FL_CLOSE;
        lock.fl_start = 0;
        lock.fl_end = OFFSET_MAX;
	...

Note the FL_CLOSE flag, which hints the VFS code that this unlocking
is done for closing the fd.

filp_close()
  locks_remove_posix(filp, id);
    vfs_lock_file(filp, F_SETLK, &lock, NULL);
      return filp->f_op->lock(filp, cmd, fl) => cifs_lock()
        rc = cifs_setlk(file, flock, type, wait_flag, posix_lck, lock, unlock, xid);
          rc = server->ops->mand_unlock_range(cfile, flock, xid);
          if (flock->fl_flags & FL_POSIX && !rc)
                  rc = locks_lock_file_wait(file, flock)

Notice how we don't call locks_lock_file_wait() which does the
generic VFS lock/unlock/wait work on the inode if rc != 0.

If we are closing the handle, the SMB server is supposed to remove any
locks associated with it. Similarly, cifs.ko frees and wakes up any
lock and lock waiter when closing the file:

cifs_close()
  cifsFileInfo_put(file->private_data)
	/*
	 * Delete any outstanding lock records. We'll lose them when the file
	 * is closed anyway.
	 */
	down_write(&cifsi->lock_sem);
	list_for_each_entry_safe(li, tmp, &cifs_file->llist->locks, llist) {
		list_del(&li->llist);
		cifs_del_lock_waiters(li);
		kfree(li);
	}
	list_del(&cifs_file->llist->llist);
	kfree(cifs_file->llist);
	up_write(&cifsi->lock_sem);

So we can safely ignore unlocking failures in cifs_lock() if they
happen with the FL_CLOSE flag hint set as both the server and the
client take care of it during the actual closing.

This is not a proper fix for the unlocking failure but it's safe and
it seems to prevent the lock leakages and crashes the customer
experiences.
Signed-off-by: NAurelien Aptel <aaptel@suse.com>
Signed-off-by: NNeilBrown <neil@brown.name>
Signed-off-by: NSteve French <stfrench@microsoft.com>
Acked-by: NPavel Shilovsky <pshilov@microsoft.com>

For debugging purposes we often have to be able to query
additional information only available via SMB3 FSCTL
from the server from user space tools (e.g. like
cifs-utils's smbinfo).  See MS-FSCC and MS-SMB2 protocol
specifications for more details.
Signed-off-by: NRonnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: NSteve French <stfrench@microsoft.com>

smb2_set_sparse does not return -errno, it returns a boolean where
true means success.
Change this to just ignore the return value just like the other callsites.

Additionally add code to handle the case where we must set the file sparse
and possibly also extending it.

Fixes xfstests: generic/236 generic/350 generic/420
Signed-off-by: NRonnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: NSteve French <stfrench@microsoft.com>

As Sergey Senozhatsky pointed out __constant_cpu_to_le32()
is misspelled in a few definitions in the list of status
codes smb2status.h as __constanst_cpu_to_le32()
Signed-off-by: NSteve French <stfrench@microsoft.com>
CC: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>

This cleanup removes cifs specific code from SMB2/SMB3 code paths
which is cleaner and easier to maintain as the code to handle
special files is improved.  Below is an example creating special files
using 'sfu' mount option over SMB3 to Windows (with this patch)
(Note that to Samba server, support for saving dos attributes
has to be enabled for the SFU mount option to work).

In the future this will also make implementation of creating
special files as reparse points easier (as Windows NFS server does
for example).

   root@smf-Thinkpad-P51:~# stat -c "%F" /mnt2/char
   character special file

   root@smf-Thinkpad-P51:~# stat -c "%F" /mnt2/block
   block special file
Signed-off-by: NAurelien Aptel <aaptel@suse.com>
Signed-off-by: NSteve French <stfrench@microsoft.com>
Reviewed-by: NRonnie Sahlberg <lsahlber@redhat.com>

Also updated a comment describing use of the GlobalMid_Lock
Signed-off-by: NSteve French <stfrench@microsoft.com>

Detected by CoverityScan CID#1438719 ("Unused Value")

buf is reset again before being used so these two lines of code
are useless.
Signed-off-by: NSteve French <stfrench@microsoft.com>
Reviewed-by: NRonnie Sahlberg <lsahlber@redhat.com>

The passthrough queries from user space tools like smbinfo can be either
SMB3 QUERY_INFO or SMB3 FSCTL, but we are not checking for the latter.
Temporarily we return EOPNOTSUPP for SMB3 FSCTL passthrough requests
but once compounding fsctls is fixed can enable.
Signed-off-by: NSteve French <stfrench@microsoft.com>
Reviewed-by: NRonnie Sahlberg <lsahlber@redhat.com>

Can be helpful in debugging various xfstests that are currently
skipped or failing due to missing features in our current
implementation of fallocate.
Signed-off-by: NSteve French <stfrench@microsoft.com>
Reviewed-by: NRonnie Sahlberg <lsahlber@redhat.com>

This allows fallocate -z to work against a Windows2016 share.

This is due to the SMB3 ZERO_RANGE command does not modify the filesize.
To address this we will now append a compounded SET-INFO to update the
end-of-file information.

This brings xfstests generic/469 closer to working against a windows share.
Signed-off-by: NRonnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: NSteve French <stfrench@microsoft.com>

Define an _init() and a _free() function for SMB2_init so that we will
be able to use it with compounds.
Signed-off-by: NRonnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: NSteve French <stfrench@microsoft.com>

Adds trace points for enter and exit (done vs. error) for:

	compounded query and setinfo, hardlink, rename,
	mkdir, rmdir, set_eof, delete (unlink)
Signed-off-by: NSteve French <stfrench@microsoft.com>
Reviewed-by: NRonnie Sahlberg <lsahlber@redhat.com>

When we open the shared root handle also ask for FILE_ALL_INFORMATION since
we can do this at zero cost as part of a compound.
Cache this information as long as the lease is held and return and serve any
future requests from cache.

This allows us to serve "stat /<mountpoint>" directly from cache and avoid
a network roundtrip.  Since clients often want to do this quite a lot
this improve performance slightly.

As an example: xfstest generic/533 performs 43 stat operations on the root
of the share while it is run. Which are eliminated with this patch.
Signed-off-by: NRonnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: NSteve French <stfrench@microsoft.com>
Reviewed-by: NPavel Shilovsky <pshilov@microsoft.com>

It can be helpful for debugging.  According to MS-FSCC:

"A 32-bit unsigned integer that contains the serial number of the
volume. The serial number is an opaque value generated by the file
system at format time"
Signed-off-by: NSteve French <stfrench@microsoft.com>
Acked-by: NPavel Shilovsky <pshilov@microsoft.com>

Since we can now wait for multiple requests atomically in
wait_for_free_request() we can now greatly simplify the handling
of the credits in this function.

This fixes a potential deadlock where many concurrent compound requests
could each have reserved 1 or 2 credits each but are all blocked
waiting for the final credits they need to be able to issue the requests
to the server.

Set a default timeout of 60 seconds for compounded requests.
Signed-off-by: NRonnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: NSteve French <stfrench@microsoft.com>
Reviewed-by: NPavel Shilovsky <pshilov@microsoft.com>