From ce720f2e5375229e2bdcb44424b185f30dae25b6 Mon Sep 17 00:00:00 2001
From: Eric Dumazet <edumazet@google.com>
Date: Wed, 18 Oct 2017 17:02:03 -0700
Subject: [PATCH 2/7] ipv4: ipv4_default_advmss() should use route mtu
Git-commit: 164a5e7ad531e181334a3d3f03d0d5ad20d6faea
Patch-mainline: 4.15-rc1
References: git-fixes
ipv4_default_advmss() incorrectly uses the device MTU instead
of the route provided one. IPv6 has the proper behavior,
lets harmonize the two protocols.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Denis Kirjanov <denis.kirjanov@suse.com>
---
net/ipv4/route.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/net/ipv4/route.c b/net/ipv4/route.c
index e55ec9708d88..87671aa02fd5 100644
--- a/net/ipv4/route.c
+++ b/net/ipv4/route.c
@@ -1319,7 +1319,7 @@ static void set_class_tag(struct rtable *rt, u32 tag)
static unsigned int ipv4_default_advmss(const struct dst_entry *dst)
{
unsigned int header_size = sizeof(struct tcphdr) + sizeof(struct iphdr);
- unsigned int advmss = max_t(unsigned int, dst->dev->mtu - header_size,
+ unsigned int advmss = max_t(unsigned int, ipv4_mtu(dst) - header_size,
ip_rt_min_advmss);
return min(advmss, IPV4_MAX_PMTU - header_size);
--
2.16.4