[PATCH 5.0 036/137] mISDN: Check address length before reading address family

From: Greg Kroah-Hartman
Date: Wed May 15 2019 - 07:31:02 EST


[ Upstream commit 238ffdc49ef98b15819cfd5e3fb23194e3ea3d39 ]

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@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/isdn/mISDN/socket.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/isdn/mISDN/socket.c b/drivers/isdn/mISDN/socket.c
index 15d3ca37669a4..04da3a17cd950 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);
--
2.20.1