Commit e3c42b61 authored Jun 23, 2017 by Mateusz Jurczyk Committed by David S. Miller Jun 25, 2017

af_iucv: Move sockaddr length checks to before accessing sa_family in bind and connect handlers



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: 52a82e23 ("af_iucv: Validate socket address length in iucv_sock_bind()")
Signed-off-by: Mateusz Jurczyk <mjurczyk@google.com>
[jwi: removed unneeded null-check for addr]
Signed-off-by: Julian Wiedmann <jwi@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

parent 2e56c26b

net/iucv/af_iucv.c

+3 −5

Original line number	Diff line number	Diff line
		@@ -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)

Admin message