diff options
| author | Paulo Alcantara <pc@manguebit.com> | 2023-12-15 19:59:14 -0300 |
|---|---|---|
| committer | Steve French <stfrench@microsoft.com> | 2023-12-17 19:02:59 -0600 |
| commit | b35858b3786ddbb56e1c35138ba25d6adf8d0bef (patch) | |
| tree | 75b21a78ae61236fe115914285fd412880299ec2 | |
| parent | 33eae65c6f49770fec7a662935d4eb4a6406d24b (diff) | |
| download | linux-b35858b3786ddbb56e1c35138ba25d6adf8d0bef.tar.gz | |
smb: client: fix OOB in smbCalcSize()
Validate @smb->WordCount to avoid reading off the end of @smb and thus
causing the following KASAN splat:
BUG: KASAN: slab-out-of-bounds in smbCalcSize+0x32/0x40 [cifs]
Read of size 2 at addr ffff88801c024ec5 by task cifsd/1328
CPU: 1 PID: 1328 Comm: cifsd Not tainted 6.7.0-rc5 #9
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS
rel-1.16.2-3-gd478f380-rebuilt.opensuse.org 04/01/2014
Call Trace:
<TASK>
dump_stack_lvl+0x4a/0x80
print_report+0xcf/0x650
? srso_alias_return_thunk+0x5/0xfbef5
? srso_alias_return_thunk+0x5/0xfbef5
? __phys_addr+0x46/0x90
kasan_report+0xd8/0x110
? smbCalcSize+0x32/0x40 [cifs]
? smbCalcSize+0x32/0x40 [cifs]
kasan_check_range+0x105/0x1b0
smbCalcSize+0x32/0x40 [cifs]
checkSMB+0x162/0x370 [cifs]
? __pfx_checkSMB+0x10/0x10 [cifs]
cifs_handle_standard+0xbc/0x2f0 [cifs]
? srso_alias_return_thunk+0x5/0xfbef5
cifs_demultiplex_thread+0xed1/0x1360 [cifs]
? __pfx_cifs_demultiplex_thread+0x10/0x10 [cifs]
? srso_alias_return_thunk+0x5/0xfbef5
? lockdep_hardirqs_on_prepare+0x136/0x210
? __pfx_lock_release+0x10/0x10
? srso_alias_return_thunk+0x5/0xfbef5
? mark_held_locks+0x1a/0x90
? lockdep_hardirqs_on_prepare+0x136/0x210
? srso_alias_return_thunk+0x5/0xfbef5
? srso_alias_return_thunk+0x5/0xfbef5
? __kthread_parkme+0xce/0xf0
? __pfx_cifs_demultiplex_thread+0x10/0x10 [cifs]
kthread+0x18d/0x1d0
? kthread+0xdb/0x1d0
? __pfx_kthread+0x10/0x10
ret_from_fork+0x34/0x60
? __pfx_kthread+0x10/0x10
ret_from_fork_asm+0x1b/0x30
</TASK>
This fixes CVE-2023-6606.
Reported-by: j51569436@gmail.com
Closes: https://bugzilla.kernel.org/show_bug.cgi?id=218218
Cc: stable@vger.kernel.org
Signed-off-by: Paulo Alcantara (SUSE) <pc@manguebit.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
| -rw-r--r-- | fs/smb/client/misc.c | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/fs/smb/client/misc.c b/fs/smb/client/misc.c index 35b176457bbed0..c2137ea3c25389 100644 --- a/fs/smb/client/misc.c +++ b/fs/smb/client/misc.c @@ -363,6 +363,10 @@ checkSMB(char *buf, unsigned int total_read, struct TCP_Server_Info *server) cifs_dbg(VFS, "Length less than smb header size\n"); } return -EIO; + } else if (total_read < sizeof(*smb) + 2 * smb->WordCount) { + cifs_dbg(VFS, "%s: can't read BCC due to invalid WordCount(%u)\n", + __func__, smb->WordCount); + return -EIO; } /* otherwise, there is enough to get to the BCC */ |