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  1. 08 8月, 2018 26 次提交
  3. 06 7月, 2018 8 次提交
    • S
      cifs: Fix stack out-of-bounds in smb{2,3}_create_lease_buf() · 729c0c9d
      由 Stefano Brivio 提交于 
      smb{2,3}_create_lease_buf() store a lease key in the lease
context for later usage on a lease break.

In most paths, the key is currently sourced from data that
happens to be on the stack near local variables for oplock in
SMB2_open() callers, e.g. from open_shroot(), whereas
smb2_open_file() properly allocates space on its stack for it.

The address of those local variables holding the oplock is then
passed to create_lease_buf handlers via SMB2_open(), and 16
bytes near oplock are used. This causes a stack out-of-bounds
access as reported by KASAN on SMB2.1 and SMB3 mounts (first
out-of-bounds access is shown here):

[  111.528823] BUG: KASAN: stack-out-of-bounds in smb3_create_lease_buf+0x399/0x3b0 [cifs]
[  111.530815] Read of size 8 at addr ffff88010829f249 by task mount.cifs/985
[  111.532838] CPU: 3 PID: 985 Comm: mount.cifs Not tainted 4.18.0-rc3+ #91
[  111.534656] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1 04/01/2014
[  111.536838] Call Trace:
[  111.537528]  dump_stack+0xc2/0x16b
[  111.540890]  print_address_description+0x6a/0x270
[  111.542185]  kasan_report+0x258/0x380
[  111.544701]  smb3_create_lease_buf+0x399/0x3b0 [cifs]
[  111.546134]  SMB2_open+0x1ef8/0x4b70 [cifs]
[  111.575883]  open_shroot+0x339/0x550 [cifs]
[  111.591969]  smb3_qfs_tcon+0x32c/0x1e60 [cifs]
[  111.617405]  cifs_mount+0x4f3/0x2fc0 [cifs]
[  111.674332]  cifs_smb3_do_mount+0x263/0xf10 [cifs]
[  111.677915]  mount_fs+0x55/0x2b0
[  111.679504]  vfs_kern_mount.part.22+0xaa/0x430
[  111.684511]  do_mount+0xc40/0x2660
[  111.698301]  ksys_mount+0x80/0xd0
[  111.701541]  do_syscall_64+0x14e/0x4b0
[  111.711807]  entry_SYSCALL_64_after_hwframe+0x44/0xa9
[  111.713665] RIP: 0033:0x7f372385b5fa
[  111.715311] Code: 48 8b 0d 99 78 2c 00 f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 49 89 ca b8 a5 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 66 78 2c 00 f7 d8 64 89 01 48
[  111.720330] RSP: 002b:00007ffff27049d8 EFLAGS: 00000206 ORIG_RAX: 00000000000000a5
[  111.722601] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f372385b5fa
[  111.724842] RDX: 000055c2ecdc73b2 RSI: 000055c2ecdc73f9 RDI: 00007ffff270580f
[  111.727083] RBP: 00007ffff2705804 R08: 000055c2ee976060 R09: 0000000000001000
[  111.729319] R10: 0000000000000000 R11: 0000000000000206 R12: 00007f3723f4d000
[  111.731615] R13: 000055c2ee976060 R14: 00007f3723f4f90f R15: 0000000000000000

[  111.735448] The buggy address belongs to the page:
[  111.737420] page:ffffea000420a7c0 count:0 mapcount:0 mapping:0000000000000000 index:0x0
[  111.739890] flags: 0x17ffffc0000000()
[  111.741750] raw: 0017ffffc0000000 0000000000000000 dead000000000200 0000000000000000
[  111.744216] raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000
[  111.746679] page dumped because: kasan: bad access detected

[  111.750482] Memory state around the buggy address:
[  111.752562]  ffff88010829f100: 00 f2 f2 f2 f2 f2 f2 f2 00 00 00 00 00 00 00 00
[  111.754991]  ffff88010829f180: 00 00 f2 f2 00 00 00 00 00 00 00 00 00 00 00 00
[  111.757401] >ffff88010829f200: 00 00 00 00 00 f1 f1 f1 f1 01 f2 f2 f2 f2 f2 f2
[  111.759801]                                               ^
[  111.762034]  ffff88010829f280: f2 02 f2 f2 f2 f2 f2 f2 f2 00 00 00 00 00 00 00
[  111.764486]  ffff88010829f300: f2 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
[  111.766913] ==================================================================

Lease keys are however already generated and stored in fid data
on open and create paths: pass them down to the lease context
creation handlers and use them.
Suggested-by: NAurélien Aptel <aaptel@suse.com>
Reviewed-by: NAurelien Aptel <aaptel@suse.com>
Fixes: b8c32dbb ("CIFS: Request SMB2.1 leases")
Signed-off-by: NStefano Brivio <sbrivio@redhat.com>
Signed-off-by: NSteve French <stfrench@microsoft.com>
      729c0c9d
    • P
      cifs: Fix infinite loop when using hard mount option · 7ffbe655
      由 Paulo Alcantara 提交于 
      For every request we send, whether it is SMB1 or SMB2+, we attempt to
reconnect tcon (cifs_reconnect_tcon or smb2_reconnect) before carrying
out the request.

So, while server->tcpStatus != CifsNeedReconnect, we wait for the
reconnection to succeed on wait_event_interruptible_timeout(). If it
returns, that means that either the condition was evaluated to true, or
timeout elapsed, or it was interrupted by a signal.

Since we're not handling the case where the process woke up due to a
received signal (-ERESTARTSYS), the next call to
wait_event_interruptible_timeout() will _always_ fail and we end up
looping forever inside either cifs_reconnect_tcon() or smb2_reconnect().

Here's an example of how to trigger that:

$ mount.cifs //foo/share /mnt/test -o
username=foo,password=foo,vers=1.0,hard

(break connection to server before executing bellow cmd)
$ stat -f /mnt/test & sleep 140
[1] 2511

$ ps -aux -q 2511
USER       PID %CPU %MEM    VSZ   RSS TTY      STAT START   TIME COMMAND
root      2511  0.0  0.0  12892  1008 pts/0    S    12:24   0:00 stat -f
/mnt/test

$ kill -9 2511

(wait for a while; process is stuck in the kernel)
$ ps -aux -q 2511
USER       PID %CPU %MEM    VSZ   RSS TTY      STAT START   TIME COMMAND
root      2511 83.2  0.0  12892  1008 pts/0    R    12:24  30:01 stat -f
/mnt/test

By using 'hard' mount point means that cifs.ko will keep retrying
indefinitely, however we must allow the process to be killed otherwise
it would hang the system.
Signed-off-by: NPaulo Alcantara <palcantara@suse.de>
Cc: stable@vger.kernel.org
Reviewed-by: NAurelien Aptel <aaptel@suse.com>
Signed-off-by: NSteve French <stfrench@microsoft.com>
      7ffbe655
    • S
      cifs: Fix slab-out-of-bounds in send_set_info() on SMB2 ACE setting · f46ecbd9
      由 Stefano Brivio 提交于 
      A "small" CIFS buffer is not big enough in general to hold a
setacl request for SMB2, and we end up overflowing the buffer in
send_set_info(). For instance:

 # mount.cifs //127.0.0.1/test /mnt/test -o username=test,password=test,nounix,cifsacl
 # touch /mnt/test/acltest
 # getcifsacl /mnt/test/acltest
 REVISION:0x1
 CONTROL:0x9004
 OWNER:S-1-5-21-2926364953-924364008-418108241-1000
 GROUP:S-1-22-2-1001
 ACL:S-1-5-21-2926364953-924364008-418108241-1000:ALLOWED/0x0/0x1e01ff
 ACL:S-1-22-2-1001:ALLOWED/0x0/R
 ACL:S-1-22-2-1001:ALLOWED/0x0/R
 ACL:S-1-5-21-2926364953-924364008-418108241-1000:ALLOWED/0x0/0x1e01ff
 ACL:S-1-1-0:ALLOWED/0x0/R
 # setcifsacl -a "ACL:S-1-22-2-1004:ALLOWED/0x0/R" /mnt/test/acltest

this setacl will cause the following KASAN splat:

[  330.777927] BUG: KASAN: slab-out-of-bounds in send_set_info+0x4dd/0xc20 [cifs]
[  330.779696] Write of size 696 at addr ffff88010d5e2860 by task setcifsacl/1012

[  330.781882] CPU: 1 PID: 1012 Comm: setcifsacl Not tainted 4.18.0-rc2+ #2
[  330.783140] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1 04/01/2014
[  330.784395] Call Trace:
[  330.784789]  dump_stack+0xc2/0x16b
[  330.786777]  print_address_description+0x6a/0x270
[  330.787520]  kasan_report+0x258/0x380
[  330.788845]  memcpy+0x34/0x50
[  330.789369]  send_set_info+0x4dd/0xc20 [cifs]
[  330.799511]  SMB2_set_acl+0x76/0xa0 [cifs]
[  330.801395]  set_smb2_acl+0x7ac/0xf30 [cifs]
[  330.830888]  cifs_xattr_set+0x963/0xe40 [cifs]
[  330.840367]  __vfs_setxattr+0x84/0xb0
[  330.842060]  __vfs_setxattr_noperm+0xe6/0x370
[  330.843848]  vfs_setxattr+0xc2/0xd0
[  330.845519]  setxattr+0x258/0x320
[  330.859211]  path_setxattr+0x15b/0x1b0
[  330.864392]  __x64_sys_setxattr+0xc0/0x160
[  330.866133]  do_syscall_64+0x14e/0x4b0
[  330.876631]  entry_SYSCALL_64_after_hwframe+0x44/0xa9
[  330.878503] RIP: 0033:0x7ff2e507db0a
[  330.880151] Code: 48 8b 0d 89 93 2c 00 f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 49 89 ca b8 bc 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 56 93 2c 00 f7 d8 64 89 01 48
[  330.885358] RSP: 002b:00007ffdc4903c18 EFLAGS: 00000246 ORIG_RAX: 00000000000000bc
[  330.887733] RAX: ffffffffffffffda RBX: 000055d1170de140 RCX: 00007ff2e507db0a
[  330.890067] RDX: 000055d1170de7d0 RSI: 000055d115b39184 RDI: 00007ffdc4904818
[  330.892410] RBP: 0000000000000001 R08: 0000000000000000 R09: 000055d1170de7e4
[  330.894785] R10: 00000000000002b8 R11: 0000000000000246 R12: 0000000000000007
[  330.897148] R13: 000055d1170de0c0 R14: 0000000000000008 R15: 000055d1170de550

[  330.901057] Allocated by task 1012:
[  330.902888]  kasan_kmalloc+0xa0/0xd0
[  330.904714]  kmem_cache_alloc+0xc8/0x1d0
[  330.906615]  mempool_alloc+0x11e/0x380
[  330.908496]  cifs_small_buf_get+0x35/0x60 [cifs]
[  330.910510]  smb2_plain_req_init+0x4a/0xd60 [cifs]
[  330.912551]  send_set_info+0x198/0xc20 [cifs]
[  330.914535]  SMB2_set_acl+0x76/0xa0 [cifs]
[  330.916465]  set_smb2_acl+0x7ac/0xf30 [cifs]
[  330.918453]  cifs_xattr_set+0x963/0xe40 [cifs]
[  330.920426]  __vfs_setxattr+0x84/0xb0
[  330.922284]  __vfs_setxattr_noperm+0xe6/0x370
[  330.924213]  vfs_setxattr+0xc2/0xd0
[  330.926008]  setxattr+0x258/0x320
[  330.927762]  path_setxattr+0x15b/0x1b0
[  330.929592]  __x64_sys_setxattr+0xc0/0x160
[  330.931459]  do_syscall_64+0x14e/0x4b0
[  330.933314]  entry_SYSCALL_64_after_hwframe+0x44/0xa9

[  330.936843] Freed by task 0:
[  330.938588] (stack is not available)

[  330.941886] The buggy address belongs to the object at ffff88010d5e2800
 which belongs to the cache cifs_small_rq of size 448
[  330.946362] The buggy address is located 96 bytes inside of
 448-byte region [ffff88010d5e2800, ffff88010d5e29c0)
[  330.950722] The buggy address belongs to the page:
[  330.952789] page:ffffea0004357880 count:1 mapcount:0 mapping:ffff880108fdca80 index:0x0 compound_mapcount: 0
[  330.955665] flags: 0x17ffffc0008100(slab|head)
[  330.957760] raw: 0017ffffc0008100 dead000000000100 dead000000000200 ffff880108fdca80
[  330.960356] raw: 0000000000000000 0000000080100010 00000001ffffffff 0000000000000000
[  330.963005] page dumped because: kasan: bad access detected

[  330.967039] Memory state around the buggy address:
[  330.969255]  ffff88010d5e2880: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
[  330.971833]  ffff88010d5e2900: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
[  330.974397] >ffff88010d5e2980: 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc
[  330.976956]                                            ^
[  330.979226]  ffff88010d5e2a00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[  330.981755]  ffff88010d5e2a80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[  330.984225] ==================================================================

Fix this by allocating a regular CIFS buffer in
smb2_plain_req_init() if the request command is SMB2_SET_INFO.
Reported-by: NJianhong Yin <jiyin@redhat.com>
Fixes: 366ed846 ("cifs: Use smb 2 - 3 and cifsacl mount options setacl function")
CC: Stable <stable@vger.kernel.org>
Signed-off-by: NStefano Brivio <sbrivio@redhat.com>
Reviewed-and-tested-by: NAurelien Aptel <aaptel@suse.com>
Signed-off-by: NSteve French <stfrench@microsoft.com>
      f46ecbd9
    • P
      cifs: Fix memory leak in smb2_set_ea() · 6aa0c114
      由 Paulo Alcantara 提交于 
      This patch fixes a memory leak when doing a setxattr(2) in SMB2+.
Signed-off-by: NPaulo Alcantara <palcantara@suse.de>
Cc: stable@vger.kernel.org
Signed-off-by: NSteve French <stfrench@microsoft.com>
Reviewed-by: NAurelien Aptel <aaptel@suse.com>
      6aa0c114
    • R
      cifs: fix SMB1 breakage · 81f39f95
      由 Ronnie Sahlberg 提交于 
      SMB1 mounting broke in commit 35e2cc1b
("cifs: Use correct packet length in SMB2_TRANSFORM header")
Fix it and also rename smb2_rqst_len to smb_rqst_len
to make it less unobvious that the function is also called from
CIFS/SMB1

Good job by Paulo reviewing and cleaning up Ronnie's original patch.
Signed-off-by: NRonnie Sahlberg <lsahlber@redhat.com>
Reviewed-by: NPaulo Alcantara <palcantara@suse.de>
Signed-off-by: NSteve French <stfrench@microsoft.com>
      81f39f95
    • P
      cifs: Fix validation of signed data in smb2 · 8de8c460
      由 Paulo Alcantara 提交于 
      Fixes: c713c877 ("cifs: push rfc1002 generation down the stack")

We failed to validate signed data returned by the server because
__cifs_calc_signature() now expects to sign the actual data in iov but
we were also passing down the rfc1002 length.

Fix smb3_calc_signature() to calculate signature of rfc1002 length prior
to passing only the actual data iov[1-N] to __cifs_calc_signature(). In
addition, there are a few cases where no rfc1002 length is passed so we
make sure there's one (iov_len == 4).
Signed-off-by: NPaulo Alcantara <palcantara@suse.de>
Reviewed-by: NRonnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: NSteve French <stfrench@microsoft.com>
      8de8c460
    • P
      cifs: Fix validation of signed data in smb3+ · 27c32b49
      由 Paulo Alcantara 提交于 
      Fixes: c713c877 ("cifs: push rfc1002 generation down the stack")

We failed to validate signed data returned by the server because
__cifs_calc_signature() now expects to sign the actual data in iov but
we were also passing down the rfc1002 length.

Fix smb3_calc_signature() to calculate signature of rfc1002 length prior
to passing only the actual data iov[1-N] to __cifs_calc_signature(). In
addition, there are a few cases where no rfc1002 length is passed so we
make sure there's one (iov_len == 4).
Signed-off-by: NPaulo Alcantara <palcantara@suse.de>
Reviewed-by: NRonnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: NSteve French <stfrench@microsoft.com>
      27c32b49
    • L
      cifs: Fix use after free of a mid_q_entry · 696e420b
      由 Lars Persson 提交于 
      With protocol version 2.0 mounts we have seen crashes with corrupt mid
entries. Either the server->pending_mid_q list becomes corrupt with a
cyclic reference in one element or a mid object fetched by the
demultiplexer thread becomes overwritten during use.

Code review identified a race between the demultiplexer thread and the
request issuing thread. The demultiplexer thread seems to be written
with the assumption that it is the sole user of the mid object until
it calls the mid callback which either wakes the issuer task or
deletes the mid.

This assumption is not true because the issuer task can be woken up
earlier by a signal. If the demultiplexer thread has proceeded as far
as setting the mid_state to MID_RESPONSE_RECEIVED then the issuer
thread will happily end up calling cifs_delete_mid while the
demultiplexer thread still is using the mid object.

Inserting a delay in the cifs demultiplexer thread widens the race
window and makes reproduction of the race very easy:

		if (server->large_buf)
			buf = server->bigbuf;

+		usleep_range(500, 4000);

		server->lstrp = jiffies;

To resolve this I think the proper solution involves putting a
reference count on the mid object. This patch makes sure that the
demultiplexer thread holds a reference until it has finished
processing the transaction.

Cc: stable@vger.kernel.org
Signed-off-by: NLars Persson <larper@axis.com>
Acked-by: NPaulo Alcantara <palcantara@suse.de>
Reviewed-by: NRonnie Sahlberg <lsahlber@redhat.com>
Reviewed-by: NPavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: NSteve French <stfrench@microsoft.com>
      696e420b
  5. 16 6月, 2018 2 次提交
  7. 15 6月, 2018 4 次提交
    • S
      smb3: fix corrupt path in subdirs on smb311 with posix · d819d298
      由 Steve French 提交于 
      Signed-off-by: NSteve French <stfrench@microsoft.com>
      d819d298
    • S
      smb3: do not display empty interface list · 115d5d28
      由 Steve French 提交于 
      If server does not support listing interfaces then do not
display empty "Server interfaces" line to avoid confusing users.
Signed-off-by: NSteve French <stfrench@microsoft.com>
CC: Aurelien Aptel <aaptel@suse.com>
      115d5d28
    • S
      smb3: Fix mode on mkdir on smb311 mounts · bea851b8
      由 Steve French 提交于 
      mkdir was not passing the mode on smb3.11 mounts with posix extensions
Signed-off-by: NSteve French <stfrench@microsoft.com>
      bea851b8
    • P
      cifs: Fix kernel oops when traceSMB is enabled · 662bf5bc
      由 Paulo Alcantara 提交于 
      When traceSMB is enabled through 'echo 1 > /proc/fs/cifs/traceSMB', after a
mount, the following oops is triggered:

[   27.137943] BUG: unable to handle kernel paging request at
ffff8800f80c268b
[   27.143396] PGD 2c6b067 P4D 2c6b067 PUD 0
[   27.145386] Oops: 0000 [#1] SMP PTI
[   27.146186] CPU: 2 PID: 2655 Comm: mount.cifs Not tainted 4.17.0+ #39
[   27.147174] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS
1.0.0-prebuilt.qemu-project.org 04/01/2014
[   27.148969] RIP: 0010:hex_dump_to_buffer+0x413/0x4b0
[   27.149738] Code: 48 8b 44 24 08 31 db 45 31 d2 48 89 6c 24 18 44 89
6c 24 24 48 c7 c1 78 b5 23 82 4c 89 64 24 10 44 89 d5 41 89 dc 4c 8d 58
02 <44> 0f b7 00 4d 89 dd eb 1f 83 c5 01 41 01 c4 41 39 ef 0f 84 48 fe
[   27.152396] RSP: 0018:ffffc9000058f8c0 EFLAGS: 00010246
[   27.153129] RAX: ffff8800f80c268b RBX: 0000000000000000 RCX:
ffffffff8223b578
[   27.153867] RDX: 0000000000000000 RSI: ffffffff81a55496 RDI:
0000000000000008
[   27.154612] RBP: 0000000000000000 R08: 0000000000000020 R09:
0000000000000083
[   27.155355] R10: 0000000000000000 R11: ffff8800f80c268d R12:
0000000000000000
[   27.156101] R13: 0000000000000002 R14: ffffc9000058f94d R15:
0000000000000008
[   27.156838] FS:  00007f1693a6b740(0000) GS:ffff88007fd00000(0000)
knlGS:0000000000000000
[   27.158354] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   27.159093] CR2: ffff8800f80c268b CR3: 00000000798fa001 CR4:
0000000000360ee0
[   27.159892] DR0: 0000000000000000 DR1: 0000000000000000 DR2:
0000000000000000
[   27.160661] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7:
0000000000000400
[   27.161464] Call Trace:
[   27.162123]  print_hex_dump+0xd3/0x160
[   27.162814] journal-offline (2658) used greatest stack depth: 13144
bytes left
[   27.162824]  ? __release_sock+0x60/0xd0
[   27.165344]  ? tcp_sendmsg+0x31/0x40
[   27.166177]  dump_smb+0x39/0x40
[   27.166972]  ? vsnprintf+0x236/0x490
[   27.167807]  __smb_send_rqst.constprop.12+0x103/0x430
[   27.168554]  ? apic_timer_interrupt+0xa/0x20
[   27.169306]  smb_send_rqst+0x48/0xc0
[   27.169984]  cifs_send_recv+0xda/0x420
[   27.170639]  SMB2_negotiate+0x23d/0xfa0
[   27.171301]  ? vsnprintf+0x236/0x490
[   27.171961]  ? smb2_negotiate+0x19/0x30
[   27.172586]  smb2_negotiate+0x19/0x30
[   27.173257]  cifs_negotiate_protocol+0x70/0xd0
[   27.173935]  ? kstrdup+0x43/0x60
[   27.174551]  cifs_get_smb_ses+0x295/0xbe0
[   27.175260]  ? lock_timer_base+0x67/0x80
[   27.175936]  ? __internal_add_timer+0x1a/0x50
[   27.176575]  ? add_timer+0x10f/0x230
[   27.177267]  cifs_mount+0x101/0x1190
[   27.177940]  ? cifs_smb3_do_mount+0x144/0x5c0
[   27.178575]  cifs_smb3_do_mount+0x144/0x5c0
[   27.179270]  mount_fs+0x35/0x150
[   27.179930]  vfs_kern_mount.part.28+0x54/0xf0
[   27.180567]  do_mount+0x5ad/0xc40
[   27.181234]  ? kmem_cache_alloc_trace+0xed/0x1a0
[   27.181916]  ksys_mount+0x80/0xd0
[   27.182535]  __x64_sys_mount+0x21/0x30
[   27.183220]  do_syscall_64+0x4e/0x100
[   27.183882]  entry_SYSCALL_64_after_hwframe+0x44/0xa9
[   27.184535] RIP: 0033:0x7f169339055a
[   27.185192] Code: 48 8b 0d 41 d9 2b 00 f7 d8 64 89 01 48 83 c8 ff c3
66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 49 89 ca b8 a5 00 00 00 0f
05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 0e d9 2b 00 f7 d8 64 89 01 48
[   27.187268] RSP: 002b:00007fff7b44eb58 EFLAGS: 00000202 ORIG_RAX:
00000000000000a5
[   27.188515] RAX: ffffffffffffffda RBX: 00007f1693a7e70e RCX:
00007f169339055a
[   27.189244] RDX: 000055b9f97f64e5 RSI: 000055b9f97f652c RDI:
00007fff7b45074f
[   27.189974] RBP: 000055b9fb8c9260 R08: 000055b9fb8ca8f0 R09:
0000000000000000
[   27.190721] R10: 0000000000000000 R11: 0000000000000202 R12:
000055b9fb8ca8f0
[   27.191429] R13: 0000000000000000 R14: 00007f1693a7c000 R15:
00007f1693a7e91d
[   27.192167] Modules linked in:
[   27.192797] CR2: ffff8800f80c268b
[   27.193435] ---[ end trace 67404c618badf323 ]---

The problem was that dump_smb() had been called with an invalid pointer,
that is, in __smb_send_rqst(), iov[1] doesn't exist (n_vec == 1).

This patch fixes it by relying on the n_vec value to dump out the smb
packets.
Signed-off-by: NPaulo Alcantara <palcantara@suse.de>
Signed-off-by: NSteve French <stfrench@microsoft.com>
Reviewed-by: NRonnie Sahlberg <lsahlber@redhat.com>
      662bf5bc