commit 238ffdc49ef98b15819cfd5e3fb23194e3ea3d39
author Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Fri Apr 12 19:52:36 2019 +0900
committer David S. Miller <davem@davemloft.net> Fri Apr 12 10:25:03 2019 -0700
tree 6c23048270495971ca7ab13423d5ca7df6d00786
parent dd3ac9a684358b8c1d5c432ca8322aaf5e4f28ee

mISDN: Check address length before reading address family

KMSAN will complain if valid address length passed to bind() is shorter
than sizeof("struct sockaddr_mISDN"->family) bytes.

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/isdn/mISDN/socket.c

diff --git a/drivers/isdn/mISDN/socket.c b/drivers/isdn/mISDN/socket.c
index 4ab8b1b..a14e35d 100644
--- a/drivers/isdn/mISDN/socket.c
+++ b/drivers/isdn/mISDN/socket.c
@@ -710,10 +710,10 @@ base_sock_bind(struct socket *sock, struct sockaddr *addr, int addr_len)
 	struct sock *sk = sock->sk;
 	int err = 0;
 
-	if (!maddr || maddr->family != AF_ISDN)
+	if (addr_len < sizeof(struct sockaddr_mISDN))
 		return -EINVAL;
 
-	if (addr_len < sizeof(struct sockaddr_mISDN))
+	if (!maddr || maddr->family != AF_ISDN)
 		return -EINVAL;
 
 	lock_sock(sk);