From: Eric Dumazet edumazet@google.com
[ Upstream commit 164a5e7ad531e181334a3d3f03d0d5ad20d6faea ]
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: Sasha Levin alexander.levin@verizon.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 3d9f1c2f81c5..42815454ec1a 100644 --- a/net/ipv4/route.c +++ b/net/ipv4/route.c @@ -1250,7 +1250,7 @@ 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);