Check the pmtu check at the transport layer (for UDP, ICMP and raw), and send a local error if socket is PMTUDISC_DO and packet is too big. This is actually a pure bugfix for ipv6. For ipv4, it allows us to do pmtu checks in the same way as for ipv6.
Signed-off-by: John Heffner <[EMAIL PROTECTED]> --- net/ipv4/ip_output.c | 4 +++- net/ipv4/raw.c | 8 +++++--- net/ipv6/ip6_output.c | 11 ++++++----- net/ipv6/raw.c | 7 +++++-- 4 files changed, 19 insertions(+), 11 deletions(-) diff --git a/net/ipv4/ip_output.c b/net/ipv4/ip_output.c index d096332..593acf7 100644 --- a/net/ipv4/ip_output.c +++ b/net/ipv4/ip_output.c @@ -822,7 +822,9 @@ int ip_append_data(struct sock *sk, fragheaderlen = sizeof(struct iphdr) + (opt ? opt->optlen : 0); maxfraglen = ((mtu - fragheaderlen) & ~7) + fragheaderlen; - if (inet->cork.length + length > 0xFFFF - fragheaderlen) { + if (inet->cork.length + length > 0xFFFF - fragheaderlen || + (inet->pmtudisc >= IP_PMTUDISC_DO && + inet->cork.length + length > mtu)) { ip_local_error(sk, EMSGSIZE, rt->rt_dst, inet->dport, mtu-exthdrlen); return -EMSGSIZE; } diff --git a/net/ipv4/raw.c b/net/ipv4/raw.c index 87e9c16..f252f4e 100644 --- a/net/ipv4/raw.c +++ b/net/ipv4/raw.c @@ -271,10 +271,12 @@ static int raw_send_hdrinc(struct sock *sk, void *from, size_t length, struct iphdr *iph; struct sk_buff *skb; int err; + int mtu; - if (length > rt->u.dst.dev->mtu) { - ip_local_error(sk, EMSGSIZE, rt->rt_dst, inet->dport, - rt->u.dst.dev->mtu); + mtu = inet->pmtudisc == IP_PMTUDISC_DO ? dst_mtu(&rt->u.dst) : + rt->u.dst.dev->mtu; + if (length > mtu) { + ip_local_error(sk, EMSGSIZE, rt->rt_dst, inet->dport, mtu); return -EMSGSIZE; } if (flags&MSG_PROBE) diff --git a/net/ipv6/ip6_output.c b/net/ipv6/ip6_output.c index 3055169..711dfc3 100644 --- a/net/ipv6/ip6_output.c +++ b/net/ipv6/ip6_output.c @@ -1044,11 +1044,12 @@ int ip6_append_data(struct sock *sk, int getfrag(void *from, char *to, fragheaderlen = sizeof(struct ipv6hdr) + rt->u.dst.nfheader_len + (opt ? opt->opt_nflen : 0); maxfraglen = ((mtu - fragheaderlen) & ~7) + fragheaderlen - sizeof(struct frag_hdr); - if (mtu <= sizeof(struct ipv6hdr) + IPV6_MAXPLEN) { - if (inet->cork.length + length > sizeof(struct ipv6hdr) + IPV6_MAXPLEN - fragheaderlen) { - ipv6_local_error(sk, EMSGSIZE, fl, mtu-exthdrlen); - return -EMSGSIZE; - } + if ((mtu <= sizeof(struct ipv6hdr) + IPV6_MAXPLEN && + inet->cork.length + length > sizeof(struct ipv6hdr) + IPV6_MAXPLEN - fragheaderlen) || + (np->pmtudisc >= IPV6_PMTUDISC_DO && + inet->cork.length + length > mtu)) { + ipv6_local_error(sk, EMSGSIZE, fl, mtu-exthdrlen); + return -EMSGSIZE; } /* diff --git a/net/ipv6/raw.c b/net/ipv6/raw.c index 306d5d8..75db277 100644 --- a/net/ipv6/raw.c +++ b/net/ipv6/raw.c @@ -556,9 +556,12 @@ static int rawv6_send_hdrinc(struct sock *sk, void *from, int length, struct sk_buff *skb; unsigned int hh_len; int err; + int mtu; - if (length > rt->u.dst.dev->mtu) { - ipv6_local_error(sk, EMSGSIZE, fl, rt->u.dst.dev->mtu); + mtu = np->pmtudisc == IPV6_PMTUDISC_DO ? dst_mtu(&rt->u.dst) : + rt->u.dst.dev->mtu; + if (length > mtu) { + ipv6_local_error(sk, EMSGSIZE, fl, mtu); return -EMSGSIZE; } if (flags&MSG_PROBE) -- 1.5.0.2.gc260-dirty - To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html