diff options
Diffstat (limited to 'net/ipv6/route.c')
| -rw-r--r-- | net/ipv6/route.c | 9 |
1 files changed, 6 insertions, 3 deletions
diff --git a/net/ipv6/route.c b/net/ipv6/route.c index 636f0120d7e3..88b46967bb67 100644 --- a/net/ipv6/route.c +++ b/net/ipv6/route.c @@ -3275,11 +3275,11 @@ static unsigned int ip6_default_advmss(const struct dst_entry *dst) /* * Maximal non-jumbo IPv6 payload is IPV6_MAXPLEN and * corresponding MSS is IPV6_MAXPLEN - tcp_header_size. - * IPV6_MAXPLEN is also valid and means: "any MSS, - * rely only on pmtu discovery" + * Limit the default MSS to GSO_BY_FRAGS - 1 to avoid + * collision with the GSO_BY_FRAGS magic value (0xFFFF). */ if (mtu > IPV6_MAXPLEN - sizeof(struct tcphdr)) - mtu = IPV6_MAXPLEN; + mtu = min_t(unsigned int, IPV6_MAXPLEN, GSO_BY_FRAGS - 1); return mtu; } @@ -5053,6 +5053,9 @@ static int fib6_nh_mtu_change(struct fib6_nh *nh, void *_arg) struct inet6_dev *idev = __in6_dev_get(arg->dev); u32 mtu = f6i->fib6_pmtu; + if (!idev) + return 0; + if (mtu >= arg->mtu || (mtu < arg->mtu && mtu == idev->cnf.mtu6)) fib6_metric_set(f6i, RTAX_MTU, arg->mtu); |