From 0bd84505f16f43e588d91ec8e0834faa5d42e8b9 Mon Sep 17 00:00:00 2001 From: David Ahern Date: Wed, 17 Jul 2019 15:08:43 -0700 Subject: [PATCH] ipv6: rt6_check should return NULL if 'from' is NULL [ Upstream commit 49d05fe2c9d1b4a27761c9807fec39b8155bef9e ] Paul reported that l2tp sessions were broken after the commit referenced in the Fixes tag. Prior to this commit rt6_check returned NULL if the rt6_info 'from' was NULL - ie., the dst_entry was disconnected from a FIB entry. Restore that behavior. Fixes: 93531c674315 ("net/ipv6: separate handling of FIB entries from dst based routes") Reported-by: Paul Donohue Tested-by: Paul Donohue Signed-off-by: David Ahern Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- net/ipv6/route.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/net/ipv6/route.c b/net/ipv6/route.c index 24f7b2cf504b..81220077d62f 100644 --- a/net/ipv6/route.c +++ b/net/ipv6/route.c @@ -2214,7 +2214,7 @@ static struct dst_entry *rt6_check(struct rt6_info *rt, { u32 rt_cookie = 0; - if ((from && !fib6_get_cookie_safe(from, &rt_cookie)) || + if (!from || !fib6_get_cookie_safe(from, &rt_cookie) || rt_cookie != cookie) return NULL;