[PATCH 5.15 870/917] ksmbd: dont need 8byte alignment for request length in ksmbd_check_message

Greg Kroah-Hartman
2021-11-16T00:38:04Z

From: Namjae Jeon <linkinjeon@kernel.org>

commit b53ad8107ee873795ecb5039d46b5d5502d404f2 upstream.

When validating request length in ksmbd_check_message, 8byte alignment
is not needed for compound request. It can cause wrong validation
of request length.

Fixes: e2f34481b24d ("cifsd: add server-side procedures for SMB3")
Cc: stable@vger.kernel.org # v5.15
Acked-by: Hyunchul Lee <hyc.lee@gmail.com>
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/ksmbd/smb2misc.c | 6 ++----
1 file changed, 2 insertions(+), 4 deletions(-)

--- a/fs/ksmbd/smb2misc.c
+++ b/fs/ksmbd/smb2misc.c
@@ -358,12 +358,10 @@ int ksmbd_smb2_check_message(struct ksmb
hdr = &pdu->hdr;
}

- if (le32_to_cpu(hdr->NextCommand) > 0) {
+ if (le32_to_cpu(hdr->NextCommand) > 0)
len = le32_to_cpu(hdr->NextCommand);
- } else if (work->next_smb2_rcv_hdr_off) {
+ else if (work->next_smb2_rcv_hdr_off)
len -= work->next_smb2_rcv_hdr_off;
- len = round_up(len, 8);
- }

if (check_smb2_hdr(hdr))
return 1;