Commit Graph

21 Commits

Author SHA1 Message Date
Zisen Ye
d62b8d236f smb/client: fix out-of-bounds read in symlink_data()
Since smb2_check_message() returns success without length validation for
the symlink error response, in symlink_data() it is possible for
iov->iov_len to be smaller than sizeof(struct smb2_err_rsp). If the buffer
only contains the base SMB2 header (64 bytes), accessing
err->ErrorContextCount (at offset 66) or err->ByteCount later in
symlink_data() will cause an out-of-bounds read.

Link: https://lore.kernel.org/linux-cifs/297d8d9b-adf7-42fd-a1c2-5b1f230032bc@chenxiaosong.com/
Fixes: 76894f3e2f ("cifs: improve symlink handling for smb2+")
Cc: Stable@vger.kernel.org
Signed-off-by: Zisen Ye <zisenye@stu.xidian.edu.cn>
Reviewed-by: ChenXiaoSong <chenxiaosong@kylinos.cn>
Signed-off-by: Steve French <stfrench@microsoft.com>
2026-05-07 14:09:29 -05:00
Paulo Alcantara
4fc3a433c1 smb: client: use atomic_t for mnt_cifs_flags
Use atomic_t for cifs_sb_info::mnt_cifs_flags as it's currently
accessed locklessly and may be changed concurrently in mount/remount
and reconnect paths.

Signed-off-by: Paulo Alcantara (Red Hat) <pc@manguebit.org>
Reviewed-by: David Howells <dhowells@redhat.com>
Cc: linux-cifs@vger.kernel.org
Signed-off-by: Steve French <stfrench@microsoft.com>
2026-02-26 18:17:08 -06:00
Linus Torvalds
bf4afc53b7 Convert 'alloc_obj' family to use the new default GFP_KERNEL argument
This was done entirely with mindless brute force, using

    git grep -l '\<k[vmz]*alloc_objs*(.*, GFP_KERNEL)' |
        xargs sed -i 's/\(alloc_objs*(.*\), GFP_KERNEL)/\1)/'

to convert the new alloc_obj() users that had a simple GFP_KERNEL
argument to just drop that argument.

Note that due to the extreme simplicity of the scripting, any slightly
more complex cases spread over multiple lines would not be triggered:
they definitely exist, but this covers the vast bulk of the cases, and
the resulting diff is also then easier to check automatically.

For the same reason the 'flex' versions will be done as a separate
conversion.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2026-02-21 17:09:51 -08:00
Kees Cook
69050f8d6d treewide: Replace kmalloc with kmalloc_obj for non-scalar types
This is the result of running the Coccinelle script from
scripts/coccinelle/api/kmalloc_objs.cocci. The script is designed to
avoid scalar types (which need careful case-by-case checking), and
instead replace kmalloc-family calls that allocate struct or union
object instances:

Single allocations:	kmalloc(sizeof(TYPE), ...)
are replaced with:	kmalloc_obj(TYPE, ...)

Array allocations:	kmalloc_array(COUNT, sizeof(TYPE), ...)
are replaced with:	kmalloc_objs(TYPE, COUNT, ...)

Flex array allocations:	kmalloc(struct_size(PTR, FAM, COUNT), ...)
are replaced with:	kmalloc_flex(*PTR, FAM, COUNT, ...)

(where TYPE may also be *VAR)

The resulting allocations no longer return "void *", instead returning
"TYPE *".

Signed-off-by: Kees Cook <kees@kernel.org>
2026-02-21 01:02:28 -08:00
Paulo Alcantara
4c91b67f87 smb: client: fix data corruption due to racy lease checks
Customer reported data corruption in some of their files.  It turned
out the client would end up calling cacheless IO functions while
having RHW lease, bypassing the pagecache and then leaving gaps in the
file while writing to it.  It was related to concurrent opens changing
the lease state while having writes in flight.  Lease breaks and
re-opens due to reconnect could also cause same issue.

Fix this by serialising the lease updates with
cifsInodeInfo::open_file_lock.  When handling oplock break, make sure
to use the downgraded oplock value rather than one in cifsInodeinfo as
it could be changed concurrently.

Reported-by: Frank Sorenson <sorenson@redhat.com>
Signed-off-by: Paulo Alcantara (Red Hat) <pc@manguebit.org>
Reviewed-by: David Howells <dhowells@redhat.com>
Cc: linux-cifs@vger.kernel.org
Signed-off-by: Steve French <stfrench@microsoft.com>
2026-02-12 17:49:55 -06:00
Shyam Prasad N
96c4af4185 cifs: Fix locking usage for tcon fields
We used to use the cifs_tcp_ses_lock to protect a lot of objects
that are not just the server, ses or tcon lists. We later introduced
srv_lock, ses_lock and tc_lock to protect fields within the
corresponding structs. This was done to provide a more granular
protection and avoid unnecessary serialization.

There were still a couple of uses of cifs_tcp_ses_lock to provide
tcon fields. In this patch, I've replaced them with tc_lock.

Cc: stable@vger.kernel.org
Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2026-02-08 17:07:43 -06:00
David Howells
83bfbd0bb9 cifs: Remove the RFC1002 header from smb_hdr
Remove the RFC1002 header from struct smb_hdr as used for SMB-1.0.  This
simplifies the SMB-1.0 code by simplifying a lot of places that have to add
or subtract 4 to work around the fact that the RFC1002 header isn't really
part of the message and the base for various offsets within the message is
from the base of the smb_hdr, not the RFC1002 header.

Further, clean up a bunch of places that require an extra kvec struct
specifically pointing to the RFC1002 header, such that kvec[0].iov_base
must be exactly 4 bytes before kvec[1].iov_base.

This allows the header preamble size stuff to be removed too.

The size of the request and response message are then handed around either
directly or by summing the size of all the iov_len members in the kvec
array for which we have a count.

Also, this simplifies and cleans up the common transmission and receive
paths for SMB1 and SMB2/3 as there no longer needs to be special handling
casing for SMB1 messages as the RFC1002 header is now generated on the fly
for SMB1 as it is for SMB2/3.

Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Tom Talpey <tom@talpey.com>
Reviewed-by: Paulo Alcantara (Red Hat) <pc@manguebit.org>
cc: Shyam Prasad N <sprasad@microsoft.com>
cc: linux-cifs@vger.kernel.org
cc: netfs@lists.linux.dev
cc: linux-fsdevel@vger.kernel.org
Signed-off-by: Steve French <stfrench@microsoft.com>
2025-12-05 17:09:32 -06:00
Eric Biggers
af5fea5141 smb: client: Use SHA-512 library for SMB3.1.1 preauth hash
Convert smb311_update_preauth_hash() to use the SHA-512 library instead
of a "sha512" crypto_shash.  This is simpler and faster.  With the
library there's no need to allocate memory, no need to handle errors,
and the SHA-512 code is accessed directly without inefficient indirect
calls and other unnecessary API overhead.

Remove the call to smb311_crypto_shash_allocate() from
smb311_update_preauth_hash(), since it appears to have been needed only
to allocate the "sha512" crypto_shash.  (It also had the side effect of
allocating the "cmac(aes)" crypto_shash, but that's also done in
generate_key() which is where the AES-CMAC key is initialized.)

For now the "sha512" crypto_shash is still being allocated elsewhere.
It will be removed in a later commit.

Reviewed-by: Stefan Metzmacher <metze@samba.org>
Acked-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Eric Biggers <ebiggers@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
2025-10-15 22:10:28 -05:00
Bharath SM
72595cb6da smb: client: add new tracepoint to trace lease break notification
Add smb3_lease_break_enter to trace lease break notifications,
recording lease state, flags, epoch, and lease key. Align
smb3_lease_not_found to use the same payload and print format.

Signed-off-by: Bharath SM <bharathsm@microsoft.com>
Acked-by: Paulo Alcantara (Red Hat) <pc@manguebit.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
2025-09-02 20:37:44 -05:00
Alexandra Diupina
b4885bd593 cifs: avoid NULL pointer dereference in dbg call
cifs_server_dbg() implies server to be non-NULL so
move call under condition to avoid NULL pointer dereference.

Found by Linux Verification Center (linuxtesting.org) with SVACE.

Fixes: e79b0332ae ("cifs: ignore cached share root handle closing errors")
Cc: stable@vger.kernel.org
Signed-off-by: Alexandra Diupina <adiupina@astralinux.ru>
Signed-off-by: Steve French <stfrench@microsoft.com>
2025-03-24 09:45:07 -05:00
Steve French
1eecd880a3 Revert "smb: client: make SHA-512 TFM ephemeral"
The original patch causes a crash with signed mounts when using
the SMB2.1 dialect

RIP: 0010:smb2_calc_signature+0x10e/0x460 [cifs]
Code: 46 30 00 00 00 00 49 c7 46 38 00 00 00 00 0f 85 3e 01 00 00 48 8b 83 a8 02 00 00 48 89 85 68 ff ff ff 49 8b b4 24 58 01 00 00 <48> 8b 38 ba 10 00 00 00 e8 55 0f 0c e0 41 89 c7 85 c0 0f 85 44 01
RSP: 0018:ffffb349422fb5c8 EFLAGS: 00010246
RAX: 0000000000000000 RBX: ffff98028765b800 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffff980200f2b100 RDI: 0000000000000000
RBP: ffffb349422fb680 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: ffff980235e37800
R13: ffffb349422fb900 R14: ffff98027c160700 R15: ffff98028765b820
FS:  000074139b98f780(0000) GS:ffff98097b980000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 000000011cb78006 CR4: 00000000003726f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 ? show_regs+0x6c/0x80
 ? __die+0x24/0x80
 ? page_fault_oops+0x175/0x5c0
 ? hrtimer_try_to_cancel.part.0+0x55/0xf0
 ? do_user_addr_fault+0x4b2/0x870
 ? exc_page_fault+0x85/0x1c0
 ? asm_exc_page_fault+0x27/0x30
 ? smb2_calc_signature+0x10e/0x460 [cifs]
 ? smb2_calc_signature+0xa7/0x460 [cifs]
 ? kmem_cache_alloc_noprof+0x101/0x300
 smb2_sign_rqst+0xa2/0xe0 [cifs]
 smb2_setup_request+0x12d/0x240 [cifs]
 compound_send_recv+0x304/0x1220 [cifs]
 cifs_send_recv+0x22/0x40 [cifs]
 SMB2_tcon+0x2d9/0x8c0 [cifs]
 cifs_get_smb_ses+0x910/0xef0 [cifs]
 ? cifs_get_smb_ses+0x910/0xef0 [cifs]
 cifs_mount_get_session+0x6a/0x250 [cifs]

Reported-by: Paulo Alcantara (Red Hat) <pc@manguebit.com>
Suggested-by: Paulo Alcantara (Red Hat) <pc@manguebit.com>
Signed-off-by: Steve French <stfrench@microsoft.com>

This reverts commit 220d83b52c.
2024-09-30 22:07:45 -05:00
Enzo Matsumiya
220d83b52c smb: client: make SHA-512 TFM ephemeral
The SHA-512 shash TFM is used only briefly during Session Setup stage,
when computing SMB 3.1.1 preauth hash.

There's no need to keep it allocated in servers' secmech the whole time,
so keep its lifetime inside smb311_update_preauth_hash().

This also makes smb311_crypto_shash_allocate() redundant, so expose
smb3_crypto_shash_allocate() and use that.

Signed-off-by: Enzo Matsumiya <ematsumiya@suse.de>
Signed-off-by: Steve French <stfrench@microsoft.com>
2024-09-26 18:15:19 -05:00
ChenXiaoSong
78181a5504 smb: move SMB2 Status code to common header file
There are only 4 different definitions between the client and server:

  - STATUS_SERVER_UNAVAILABLE: from client/smb2status.h
  - STATUS_FILE_NOT_AVAILABLE: from client/smb2status.h
  - STATUS_NO_PREAUTH_INTEGRITY_HASH_OVERLAP: from server/smbstatus.h
  - STATUS_INVALID_LOCK_RANGE: from server/smbstatus.h

Rename client/smb2status.h to common/smb2status.h, and merge the
2 different definitions of server to common header file.

Signed-off-by: ChenXiaoSong <chenxiaosong@kylinos.cn>
Acked-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
2024-09-15 10:42:44 -05:00
David Howells
afc23febd5 cifs: Add tracing for the cifs_tcon struct refcounting
Add tracing for the refcounting/lifecycle of the cifs_tcon struct, marking
different events with different labels and giving each tcon its own debug
ID so that the tracelines corresponding to individual tcons can be
distinguished.  This can be enabled with:

	echo 1 >/sys/kernel/debug/tracing/events/cifs/smb3_tcon_ref/enable

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Paulo Alcantara (Red Hat) <pc@manguebit.com>
cc: Shyam Prasad N <nspmangalore@gmail.com>
cc: linux-cifs@vger.kernel.org
cc: linux-fsdevel@vger.kernel.org
Signed-off-by: Steve French <stfrench@microsoft.com>
2024-04-19 16:02:09 -05:00
Paulo Alcantara
22863485a4 smb: client: fix potential UAF in smb2_is_valid_oplock_break()
Skip sessions that are being teared down (status == SES_EXITING) to
avoid UAF.

Cc: stable@vger.kernel.org
Signed-off-by: Paulo Alcantara (Red Hat) <pc@manguebit.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2024-04-03 14:43:45 -05:00
Paulo Alcantara
705c76fbf7 smb: client: fix potential UAF in smb2_is_valid_lease_break()
Skip sessions that are being teared down (status == SES_EXITING) to
avoid UAF.

Cc: stable@vger.kernel.org
Signed-off-by: Paulo Alcantara (Red Hat) <pc@manguebit.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2024-04-03 14:43:45 -05:00
Paulo Alcantara
567320c46a smb: client: fix potential OOB in smb2_dump_detail()
Validate SMB message with ->check_message() before calling
->calc_smb_size().

This fixes CVE-2023-6610.

Reported-by: j51569436@gmail.com
Closes: https://bugzilla.kernel.org/show_bug.cgi?id=218219
Cc; stable@vger.kernel.org
Signed-off-by: Paulo Alcantara <pc@manguebit.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2023-12-19 10:33:39 -06:00
Paulo Alcantara
90d025c2e9 smb: client: fix NULL deref in asn1_ber_decoder()
If server replied SMB2_NEGOTIATE with a zero SecurityBufferOffset,
smb2_get_data_area() sets @len to non-zero but return NULL, so
decode_negTokeninit() ends up being called with a NULL @security_blob:

  BUG: kernel NULL pointer dereference, address: 0000000000000000
  #PF: supervisor read access in kernel mode
  #PF: error_code(0x0000) - not-present page
  PGD 0 P4D 0
  Oops: 0000 [#1] PREEMPT SMP NOPTI
  CPU: 2 PID: 871 Comm: mount.cifs Not tainted 6.7.0-rc4 #2
  Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.16.2-3-gd478f380-rebuilt.opensuse.org 04/01/2014
  RIP: 0010:asn1_ber_decoder+0x173/0xc80
  Code: 01 4c 39 2c 24 75 09 45 84 c9 0f 85 2f 03 00 00 48 8b 14 24 4c 29 ea 48 83 fa 01 0f 86 1e 07 00 00 48 8b 74 24 28 4d 8d 5d 01 <42> 0f b6 3c 2e 89 fa 40 88 7c 24 5c f7 d2 83 e2 1f 0f 84 3d 07 00
  RSP: 0018:ffffc9000063f950 EFLAGS: 00010202
  RAX: 0000000000000002 RBX: 0000000000000000 RCX: 000000000000004a
  RDX: 000000000000004a RSI: 0000000000000000 RDI: 0000000000000000
  RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
  R10: 0000000000000002 R11: 0000000000000001 R12: 0000000000000000
  R13: 0000000000000000 R14: 000000000000004d R15: 0000000000000000
  FS:  00007fce52b0fbc0(0000) GS:ffff88806ba00000(0000) knlGS:0000000000000000
  CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  CR2: 0000000000000000 CR3: 000000001ae64000 CR4: 0000000000750ef0
  PKRU: 55555554
  Call Trace:
   <TASK>
   ? __die+0x23/0x70
   ? page_fault_oops+0x181/0x480
   ? __stack_depot_save+0x1e6/0x480
   ? exc_page_fault+0x6f/0x1c0
   ? asm_exc_page_fault+0x26/0x30
   ? asn1_ber_decoder+0x173/0xc80
   ? check_object+0x40/0x340
   decode_negTokenInit+0x1e/0x30 [cifs]
   SMB2_negotiate+0xc99/0x17c0 [cifs]
   ? smb2_negotiate+0x46/0x60 [cifs]
   ? srso_alias_return_thunk+0x5/0xfbef5
   smb2_negotiate+0x46/0x60 [cifs]
   cifs_negotiate_protocol+0xae/0x130 [cifs]
   cifs_get_smb_ses+0x517/0x1040 [cifs]
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? queue_delayed_work_on+0x5d/0x90
   cifs_mount_get_session+0x78/0x200 [cifs]
   dfs_mount_share+0x13a/0x9f0 [cifs]
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? lock_acquire+0xbf/0x2b0
   ? find_nls+0x16/0x80
   ? srso_alias_return_thunk+0x5/0xfbef5
   cifs_mount+0x7e/0x350 [cifs]
   cifs_smb3_do_mount+0x128/0x780 [cifs]
   smb3_get_tree+0xd9/0x290 [cifs]
   vfs_get_tree+0x2c/0x100
   ? capable+0x37/0x70
   path_mount+0x2d7/0xb80
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? _raw_spin_unlock_irqrestore+0x44/0x60
   __x64_sys_mount+0x11a/0x150
   do_syscall_64+0x47/0xf0
   entry_SYSCALL_64_after_hwframe+0x6f/0x77
  RIP: 0033:0x7fce52c2ab1e

Fix this by setting @len to zero when @off == 0 so callers won't
attempt to dereference non-existing data areas.

Reported-by: Robert Morris <rtm@csail.mit.edu>
Cc: stable@vger.kernel.org
Signed-off-by: Paulo Alcantara (SUSE) <pc@manguebit.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2023-12-11 12:30:39 -06:00
Paulo Alcantara
e6322fd177 smb: client: fix potential deadlock when releasing mids
All release_mid() callers seem to hold a reference of @mid so there is
no need to call kref_put(&mid->refcount, __release_mid) under
@server->mid_lock spinlock.  If they don't, then an use-after-free bug
would have occurred anyways.

By getting rid of such spinlock also fixes a potential deadlock as
shown below

CPU 0                                CPU 1
------------------------------------------------------------------
cifs_demultiplex_thread()            cifs_debug_data_proc_show()
 release_mid()
  spin_lock(&server->mid_lock);
                                     spin_lock(&cifs_tcp_ses_lock)
				      spin_lock(&server->mid_lock)
  __release_mid()
   smb2_find_smb_tcon()
    spin_lock(&cifs_tcp_ses_lock) *deadlock*

Cc: stable@vger.kernel.org
Signed-off-by: Paulo Alcantara (SUSE) <pc@manguebit.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2023-10-31 12:38:02 -05:00
Steve French
b3773b19d4 SMB3: rename macro CIFS_SERVER_IS_CHAN to avoid confusion
Since older dialects such as CIFS do not support multichannel
the macro CIFS_SERVER_IS_CHAN can be confusing (it requires SMB 3
or later) so shorten its name to "SERVER_IS_CHAN"

Suggested-by: Tom Talpey <tom@talpey.com>
Acked-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2023-08-30 08:55:02 -05:00
Steve French
38c8a9a520 smb: move client and server files to common directory fs/smb
Move CIFS/SMB3 related client and server files (cifs.ko and ksmbd.ko
and helper modules) to new fs/smb subdirectory:

   fs/cifs --> fs/smb/client
   fs/ksmbd --> fs/smb/server
   fs/smbfs_common --> fs/smb/common

Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Acked-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
2023-05-24 16:29:21 -05:00