[PATCH 5.15 169/179] ksmbd: Fix an error handling path in smb2_sess_setup()

From: Greg Kroah-Hartman
Date: Mon Nov 29 2021 - 17:50:08 EST


From: Christophe JAILLET <christophe.jaillet@xxxxxxxxxx>

commit f8fbfd85f5c95fff477a7c19f576725945891d0c upstream.

All the error handling paths of 'smb2_sess_setup()' end to 'out_err'.

All but the new error handling path added by the commit given in the Fixes
tag below.

Fix this error handling path and branch to 'out_err' as well.

Fixes: 0d994cd482ee ("ksmbd: add buffer validation in session setup")
Cc: stable@xxxxxxxxxxxxxxx # v5.15
Acked-by: Namjae Jeon <linkinjeon@xxxxxxxxxx>
Signed-off-by: Christophe JAILLET <christophe.jaillet@xxxxxxxxxx>
Signed-off-by: Steve French <stfrench@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
fs/ksmbd/smb2pdu.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)

--- a/fs/ksmbd/smb2pdu.c
+++ b/fs/ksmbd/smb2pdu.c
@@ -1700,8 +1700,10 @@ int smb2_sess_setup(struct ksmbd_work *w
negblob_off = le16_to_cpu(req->SecurityBufferOffset);
negblob_len = le16_to_cpu(req->SecurityBufferLength);
if (negblob_off < (offsetof(struct smb2_sess_setup_req, Buffer) - 4) ||
- negblob_len < offsetof(struct negotiate_message, NegotiateFlags))
- return -EINVAL;
+ negblob_len < offsetof(struct negotiate_message, NegotiateFlags)) {
+ rc = -EINVAL;
+ goto out_err;
+ }

negblob = (struct negotiate_message *)((char *)&req->hdr.ProtocolId +
negblob_off);