The patch below does not apply to the 5.15-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <stable@xxxxxxxxxxxxxxx>. To reproduce the conflict and resubmit, you may use the following commands: git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.15.y git checkout FETCH_HEAD git cherry-pick -x 1c1bcf2d3ea061613119b534f57507c377df20f9 # <resolve conflicts, build, test, etc.> git commit -s git send-email --to '<stable@xxxxxxxxxxxxxxx>' --in-reply-to '2023061222-comic-platypus-831e@gregkh' --subject-prefix 'PATCH 5.15.y' HEAD^.. Possible dependencies: thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From 1c1bcf2d3ea061613119b534f57507c377df20f9 Mon Sep 17 00:00:00 2001 From: Namjae Jeon <linkinjeon@xxxxxxxxxx> Date: Wed, 31 May 2023 17:59:32 +0900 Subject: [PATCH] ksmbd: validate smb request protocol id 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@xxxxxxxxxxxxxxx Reported-by: Chih-Yen Chang <cc85nod@xxxxxxxxx> Signed-off-by: Namjae Jeon <linkinjeon@xxxxxxxxxx> Signed-off-by: Steve French <stfrench@xxxxxxxxxxxxx> diff --git a/fs/smb/server/connection.c b/fs/smb/server/connection.c index e11d4a1e63d7..2a717d158f02 100644 --- a/fs/smb/server/connection.c +++ b/fs/smb/server/connection.c @@ -364,8 +364,6 @@ 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 @@ -383,6 +381,9 @@ 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/smb/server/smb_common.c b/fs/smb/server/smb_common.c index af0c2a9b8529..569e5eecdf3d 100644 --- a/fs/smb/server/smb_common.c +++ b/fs/smb/server/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)
