From: Namjae Jeon <linkinjeon@kernel.org>
Date: Mon, 18 Dec 2023 15:34:30 +0000 (+0900)
Subject: ksmbd: check iov vector index in ksmbd_conn_write()
X-Git-Tag: v5.15.145~30
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=b9a3e4549676857bf4b1b5f92200fbb1740dfa2e;p=thirdparty%2Fkernel%2Fstable.git

ksmbd: check iov vector index in ksmbd_conn_write()

[ Upstream commit 73f949ea87c7d697210653501ca21efe57295327 ]

If ->iov_idx is zero, This means that the iov vector for the response
was not added during the request process. In other words, it means that
there is a problem in generating a response, So this patch return as
an error to avoid NULL pointer dereferencing problem.

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>
---

diff --git a/fs/ksmbd/connection.c b/fs/ksmbd/connection.c
index 585f117bda8a2..9e12738a56c65 100644
--- a/fs/ksmbd/connection.c
+++ b/fs/ksmbd/connection.c
@@ -197,6 +197,9 @@ int ksmbd_conn_write(struct ksmbd_work *work)
 	if (work->send_no_response)
 		return 0;
 
+	if (!work->iov_idx)
+		return -EINVAL;
+
 	ksmbd_conn_lock(conn);
 	sent = conn->transport->ops->writev(conn->transport, work->iov,
 			work->iov_cnt,