net/packet: fix overflow in check for tp_reserve

When calculating po->tp_hdrlen + po->tp_reserve the result can overflow. Fix by checking that tp_reserve <= INT_MAX on assign. Signed-off-by: Andrey Konovalov <[email protected]> Acked-by: Eric Dumazet <[email protected]> Signed-off-by: David S. Miller <[email protected]>
mrcsosa · Mar 30, 2017 · bcc5364 · bcc5364
1 parent 8f8d28e
commit bcc5364
Showing 1 changed file with 2 additions and 0 deletions.
diff --git a/net/packet/af_packet.c b/net/packet/af_packet.c
@@ -3665,6 +3665,8 @@ packet_setsockopt(struct socket *sock, int level, int optname, char __user *optv
 			return -EBUSY;
 		if (copy_from_user(&val, optval, sizeof(val)))
 			return -EFAULT;
+		if (val > INT_MAX)
+			return -EINVAL;
 		po->tp_reserve = val;
 		return 0;
 	}