From 215eb22368830bb78f9fe41b5d6d24176529bf1e Mon Sep 17 00:00:00 2001 From: Andrey Konovalov Date: Wed, 29 Mar 2017 16:11:22 +0200 Subject: [PATCH] net/packet: fix overflow in check for tp_reserve Orabug: 25813773 CVE: CVE-2017-7308 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 Acked-by: Eric Dumazet Signed-off-by: David S. Miller (cherry picked from commit bcc5364bdcfe131e6379363f089e7b4108d35b70) Signed-off-by: Brian Maly --- net/packet/af_packet.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/net/packet/af_packet.c b/net/packet/af_packet.c index cd4af1d1a58c..282506cffa42 100644 --- a/net/packet/af_packet.c +++ b/net/packet/af_packet.c @@ -3373,6 +3373,8 @@ 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; } -- 2.50.1