ksmbd: fix slab-out-of-bounds read in smb2_handle_negotiate
authorKuan-Ting Chen <h3xrabbit@gmail.com>
Fri, 19 May 2023 13:59:28 +0000 (22:59 +0900)
committerSteve French <stfrench@microsoft.com>
Sat, 27 May 2023 01:27:46 +0000 (20:27 -0500)
commitd738950f112c8f40f0515fe967db998e8235a175
tree606e4be7f029bedf2290046d8991fc68e53765d6
parent84c5aa47925a1f40d698b6a6a2bf67e99617433d
ksmbd: fix slab-out-of-bounds read in smb2_handle_negotiate

Check request_buf length first to avoid out-of-bounds read by
req->DialectCount.

[ 3350.990282] BUG: KASAN: slab-out-of-bounds in smb2_handle_negotiate+0x35d7/0x3e60
[ 3350.990282] Read of size 2 at addr ffff88810ad61346 by task kworker/5:0/276
[ 3351.000406] Workqueue: ksmbd-io handle_ksmbd_work
[ 3351.003499] Call Trace:
[ 3351.006473]  <TASK>
[ 3351.006473]  dump_stack_lvl+0x8d/0xe0
[ 3351.006473]  print_report+0xcc/0x620
[ 3351.006473]  kasan_report+0x92/0xc0
[ 3351.006473]  smb2_handle_negotiate+0x35d7/0x3e60
[ 3351.014760]  ksmbd_smb_negotiate_common+0x7a7/0xf00
[ 3351.014760]  handle_ksmbd_work+0x3f7/0x12d0
[ 3351.014760]  process_one_work+0xa85/0x1780

Cc: stable@vger.kernel.org
Signed-off-by: Kuan-Ting Chen <h3xrabbit@gmail.com>
Acked-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
fs/smb/server/smb2pdu.c