diff options
Diffstat (limited to 'net/ipv4/icmp.c')
-rw-r--r-- | net/ipv4/icmp.c | 26 |
1 files changed, 24 insertions, 2 deletions
diff --git a/net/ipv4/icmp.c b/net/ipv4/icmp.c index 5c0e8bc6e5ba..0134663fdbce 100644 --- a/net/ipv4/icmp.c +++ b/net/ipv4/icmp.c @@ -668,6 +668,16 @@ static void icmp_socket_deliver(struct sk_buff *skb, u32 info) rcu_read_unlock(); } +static bool icmp_tag_validation(int proto) +{ + bool ok; + + rcu_read_lock(); + ok = rcu_dereference(inet_protos[proto])->icmp_strict_tag_validation; + rcu_read_unlock(); + return ok; +} + /* * Handle ICMP_DEST_UNREACH, ICMP_TIME_EXCEED, ICMP_QUENCH, and * ICMP_PARAMETERPROB. @@ -705,10 +715,22 @@ static void icmp_unreach(struct sk_buff *skb) case ICMP_PORT_UNREACH: break; case ICMP_FRAG_NEEDED: - if (ipv4_config.no_pmtu_disc) { + /* for documentation of the ip_no_pmtu_disc + * values please see + * Documentation/networking/ip-sysctl.txt + */ + switch (net->ipv4.sysctl_ip_no_pmtu_disc) { + default: LIMIT_NETDEBUG(KERN_INFO pr_fmt("%pI4: fragmentation needed and DF set\n"), &iph->daddr); - } else { + break; + case 2: + goto out; + case 3: + if (!icmp_tag_validation(iph->protocol)) + goto out; + /* fall through */ + case 0: info = ntohs(icmph->un.frag.mtu); if (!info) goto out; |