From: Namjae Jeon linkinjeon@kernel.org
[ Upstream commit 1c1bcf2d3ea061613119b534f57507c377df20f9 ]
This patch add the validation for smb request protocol id. If it is not one of the four ids(SMB1_PROTO_NUMBER, SMB2_PROTO_NUMBER, SMB2_TRANSFORM_PROTO_NUM, SMB2_COMPRESSION_TRANSFORM_ID), don't allow processing the request. And this will fix the following KASAN warning also.
[ 13.905265] BUG: KASAN: slab-out-of-bounds in init_smb2_rsp_hdr+0x1b9/0x1f0 [ 13.905900] Read of size 16 at addr ffff888005fd2f34 by task kworker/0:2/44 ... [ 13.908553] Call Trace: [ 13.908793] <TASK> [ 13.908995] dump_stack_lvl+0x33/0x50 [ 13.909369] print_report+0xcc/0x620 [ 13.910870] kasan_report+0xae/0xe0 [ 13.911519] kasan_check_range+0x35/0x1b0 [ 13.911796] init_smb2_rsp_hdr+0x1b9/0x1f0 [ 13.912492] handle_ksmbd_work+0xe5/0x820
Cc: stable@vger.kernel.org Reported-by: Chih-Yen Chang cc85nod@gmail.com Signed-off-by: Namjae Jeon linkinjeon@kernel.org Signed-off-by: Steve French stfrench@microsoft.com Signed-off-by: Sasha Levin sashal@kernel.org --- fs/ksmbd/connection.c | 5 +++-- fs/ksmbd/smb_common.c | 14 +++++++++++++- 2 files changed, 16 insertions(+), 3 deletions(-)
diff --git a/fs/ksmbd/connection.c b/fs/ksmbd/connection.c index bf8531b80a182..e1d2be19cddfa 100644 --- a/fs/ksmbd/connection.c +++ b/fs/ksmbd/connection.c @@ -366,8 +366,6 @@ int ksmbd_conn_handler_loop(void *p) break;
memcpy(conn->request_buf, hdr_buf, sizeof(hdr_buf)); - if (!ksmbd_smb_request(conn)) - break;
/* * We already read 4 bytes to find out PDU size, now @@ -385,6 +383,9 @@ int ksmbd_conn_handler_loop(void *p) continue; }
+ if (!ksmbd_smb_request(conn)) + break; + if (((struct smb2_hdr *)smb2_get_msg(conn->request_buf))->ProtocolId == SMB2_PROTO_NUMBER) { if (pdu_size < SMB2_MIN_SUPPORTED_HEADER_SIZE) diff --git a/fs/ksmbd/smb_common.c b/fs/ksmbd/smb_common.c index 95afb6b23a91c..05d7f3e910bf4 100644 --- a/fs/ksmbd/smb_common.c +++ b/fs/ksmbd/smb_common.c @@ -158,7 +158,19 @@ int ksmbd_verify_smb_message(struct ksmbd_work *work) */ bool ksmbd_smb_request(struct ksmbd_conn *conn) { - return conn->request_buf[0] == 0; + __le32 *proto = (__le32 *)smb2_get_msg(conn->request_buf); + + if (*proto == SMB2_COMPRESSION_TRANSFORM_ID) { + pr_err_ratelimited("smb2 compression not support yet"); + return false; + } + + if (*proto != SMB1_PROTO_NUMBER && + *proto != SMB2_PROTO_NUMBER && + *proto != SMB2_TRANSFORM_PROTO_NUM) + return false; + + return true; }
static bool supported_protocol(int idx)