[PATCH 6.8 156/158] ksmbd: validate request buffer size in smb2_allocate_rsp_buf()

Greg Kroah-Hartman
2024-04-23T21:42:34Z

From: Namjae Jeon <linkinjeon@kernel.org>

commit 17cf0c2794bdb6f39671265aa18aea5c22ee8c4a upstream.

The response buffer should be allocated in smb2_allocate_rsp_buf
before validating request. But the fields in payload as well as smb2 header
is used in smb2_allocate_rsp_buf(). This patch add simple buffer size
validation to avoid potencial out-of-bounds in request buffer.

Cc: stable@vger.kernel.org
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
fs/smb/server/smb2pdu.c | 4 ++++
1 file changed, 4 insertions(+)

--- a/fs/smb/server/smb2pdu.c
+++ b/fs/smb/server/smb2pdu.c
@@ -535,6 +535,10 @@ int smb2_allocate_rsp_buf(struct ksmbd_w
if (cmd == SMB2_QUERY_INFO_HE) {
struct smb2_query_info_req *req;

+ if (get_rfc1002_len(work->request_buf) <
+ offsetof(struct smb2_query_info_req, OutputBufferLength))
+ return -EINVAL;
+
req = smb2_get_msg(work->request_buf);
if ((req->InfoType == SMB2_O_INFO_FILE &&
(req->FileInfoClass == FILE_FULL_EA_INFORMATION ||