pppoe: check sockaddr length in pppoe_connect()

[ Upstream commit a49e2f5 ] We must validate sockaddr_len, otherwise userspace can pass fewer data than we expect and we end up accessing invalid data. Fixes: 224cf5a ("ppp: Move the PPP drivers") Reported-by: [email protected] Signed-off-by: Guillaume Nault <[email protected]> Signed-off-by: David S. Miller <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
rockchip-linux · Apr 29, 2018 · dedf29a · dedf29a
1 parent 183f20f
commit dedf29a
Showing 1 changed file with 4 additions and 0 deletions.
diff --git a/drivers/net/ppp/pppoe.c b/drivers/net/ppp/pppoe.c
@@ -638,6 +638,10 @@ static int pppoe_connect(struct socket *sock, struct sockaddr *uservaddr,
 	lock_sock(sk);
 
 	error = -EINVAL;
+
+	if (sockaddr_len != sizeof(struct sockaddr_pppox))
+		goto end;
+
 	if (sp->sa_protocol != PX_PROTO_OE)
 		goto end;