Verify that the caller-provided sockaddr structure is large enough to contain the sa_family field, before accessing it in bind() and connect() handlers of the AF_IUCV socket. Since neither syscall enforces a minimum size of the corresponding memory region, very short sockaddrs (zero or one byte long) result in operating on uninitialized memory while referencing .sa_family.
Signed-off-by: Mateusz Jurczyk <[email protected]> --- net/iucv/af_iucv.c | 8 +++----- 1 file changed, 3 insertions(+), 5 deletions(-) diff --git a/net/iucv/af_iucv.c b/net/iucv/af_iucv.c index 84de7b6326dc..1f63e704ab50 100644 --- a/net/iucv/af_iucv.c +++ b/net/iucv/af_iucv.c @@ -716,10 +716,8 @@ static int iucv_sock_bind(struct socket *sock, struct sockaddr *addr, char uid[9]; /* Verify the input sockaddr */ - if (!addr || addr->sa_family != AF_IUCV) - return -EINVAL; - - if (addr_len < sizeof(struct sockaddr_iucv)) + if (!addr || addr_len < sizeof(struct sockaddr_iucv) || + addr->sa_family != AF_IUCV) return -EINVAL; lock_sock(sk); @@ -863,7 +861,7 @@ static int iucv_sock_connect(struct socket *sock, struct sockaddr *addr, struct iucv_sock *iucv = iucv_sk(sk); int err; - if (addr->sa_family != AF_IUCV || alen < sizeof(struct sockaddr_iucv)) + if (alen < sizeof(struct sockaddr_iucv) || addr->sa_family != AF_IUCV) return -EINVAL; if (sk->sk_state != IUCV_OPEN && sk->sk_state != IUCV_BOUND) -- 2.13.1.508.gb3defc5cc-goog
