ipv6: ip6_append_data_mtu do not handle the mtu of the second fragment properly

[~andy/linux] / net / ipv6 / ip6_output.c

diff --git a/net/ipv6/ip6_output.c b/net/ipv6/ip6_output.c
index 16f91a2e788819b6b1755ef65a98c8cb699e0597..64d6073731d368e54073f9ca97ac6ad0cecdd415 100644 (file)
--- a/net/ipv6/ip6_output.c
+++ b/net/ipv6/ip6_output.c
@@ -1101,21 +1101,19 @@ static void ip6_append_data_mtu(unsigned int *mtu,
                                unsigned int fragheaderlen,
                                struct sk_buff *skb,
                                struct rt6_info *rt,
-                               bool pmtuprobe)
+                               unsigned int orig_mtu)
 {
        if (!(rt->dst.flags & DST_XFRM_TUNNEL)) {
                if (skb == NULL) {
                        /* first fragment, reserve header_len */
-                       *mtu = *mtu - rt->dst.header_len;
+                       *mtu = orig_mtu - rt->dst.header_len;
 
                } else {
                        /*
                         * this fragment is not first, the headers
                         * space is regarded as data space.
                         */
-                       *mtu = min(*mtu, pmtuprobe ?
-                                  rt->dst.dev->mtu :
-                                  dst_mtu(rt->dst.path));
+                       *mtu = orig_mtu;
                }
                *maxfraglen = ((*mtu - fragheaderlen) & ~7)
                              + fragheaderlen - sizeof(struct frag_hdr);
@@ -1132,7 +1130,7 @@ int ip6_append_data(struct sock *sk, int getfrag(void *from, char *to,
        struct ipv6_pinfo *np = inet6_sk(sk);
        struct inet_cork *cork;
        struct sk_buff *skb, *skb_prev = NULL;
-       unsigned int maxfraglen, fragheaderlen, mtu;
+       unsigned int maxfraglen, fragheaderlen, mtu, orig_mtu;
        int exthdrlen;
        int dst_exthdrlen;
        int hh_len;
@@ -1214,6 +1212,7 @@ int ip6_append_data(struct sock *sk, int getfrag(void *from, char *to,
                dst_exthdrlen = 0;
                mtu = cork->fragsize;
        }
+       orig_mtu = mtu;
 
        hh_len = LL_RESERVED_SPACE(rt->dst.dev);
 
@@ -1311,8 +1310,7 @@ alloc_new_skb:
                        if (skb == NULL || skb_prev == NULL)
                                ip6_append_data_mtu(&mtu, &maxfraglen,
                                                    fragheaderlen, skb, rt,
-                                                   np->pmtudisc >=
-                                                   IPV6_PMTUDISC_PROBE);
+                                                   orig_mtu);
 
                        skb_prev = skb;