4.9-stable review patch. If anyone has any objections, please let me know.
------------------
From: Mateusz Jurczyk <mjurczyk@xxxxxxxxxx>
[ Upstream commit defbcf2decc903a28d8398aa477b6881e711e3ea ]
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_UNIX 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 <mjurczyk@xxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
net/unix/af_unix.c | 7 ++++++-
1 file changed, 6 insertions(+), 1 deletion(-)
--- a/net/unix/af_unix.c
+++ b/net/unix/af_unix.c
@@ -998,7 +998,8 @@ static int unix_bind(struct socket *sock
struct path path = { NULL, NULL };
err = -EINVAL;
- if (sunaddr->sun_family != AF_UNIX)
+ if (addr_len < offsetofend(struct sockaddr_un, sun_family) ||
+ sunaddr->sun_family != AF_UNIX)
goto out;
if (addr_len == sizeof(short)) {
@@ -1109,6 +1110,10 @@ static int unix_dgram_connect(struct soc
unsigned int hash;
int err;
+ err = -EINVAL;
+ if (alen < offsetofend(struct sockaddr, sa_family))
+ goto out;
+
if (addr->sa_family != AF_UNSPEC) {
err = unix_mkname(sunaddr, alen, &hash);
if (err < 0)