From mboxrd@z Thu Jan 1 00:00:00 1970 From: Julian Wiedmann Subject: [PATCH net-next 2/2] af_iucv: Move sockaddr length checks to before accessing sa_family in bind and connect handlers Date: Fri, 23 Jun 2017 19:32:28 +0200 Message-ID: <20170623173228.70128-3-jwi@linux.vnet.ibm.com> References: <20170623173228.70128-1-jwi@linux.vnet.ibm.com> Return-path: In-Reply-To: <20170623173228.70128-1-jwi@linux.vnet.ibm.com> Sender: netdev-owner@vger.kernel.org List-Archive: List-Post: To: David Miller Cc: netdev@vger.kernel.org, linux-s390@vger.kernel.org, Martin Schwidefsky , Heiko Carstens , Stefan Raspl , Ursula Braun , Julian Wiedmann List-ID: From: Mateusz Jurczyk 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. Fixes: 52a82e23b9f2 ("af_iucv: Validate socket address length in iucv_sock_bind()") Signed-off-by: Mateusz Jurczyk [jwi: removed unneeded null-check for addr] Signed-off-by: Julian Wiedmann --- 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 05112094d76b..ac033e413bc5 100644 --- a/net/iucv/af_iucv.c +++ b/net/iucv/af_iucv.c @@ -715,10 +715,8 @@ 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_len < sizeof(struct sockaddr_iucv) || + addr->sa_family != AF_IUCV) return -EINVAL; lock_sock(sk); @@ -862,7 +860,7 @@ 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) -- 2.11.2