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authorJens Axboe <axboe@kernel.dk>2013-07-02 08:31:48 +0200
committerJens Axboe <axboe@kernel.dk>2013-07-02 08:31:48 +0200
commit5f0e5afa0de4522abb3ea7d1369039b94e740ec5 (patch)
tree6a5be3db9ecfed8ef2150c6146f6d1e0d658ac8b /net/netfilter/xt_TCPMSS.c
parentd752b2696072ed52fd5afab08b601e2220a3b87e (diff)
parent9e895ace5d82df8929b16f58e9f515f6d54ab82d (diff)
Merge tag 'v3.10-rc7' into for-3.11/drivers
Linux 3.10-rc7 Pull this in early to avoid doing it with the bcache merge, since there are a number of changes to bcache between my old base (3.10-rc1) and the new pull request.
Diffstat (limited to 'net/netfilter/xt_TCPMSS.c')
-rw-r--r--net/netfilter/xt_TCPMSS.c6
1 files changed, 6 insertions, 0 deletions
diff --git a/net/netfilter/xt_TCPMSS.c b/net/netfilter/xt_TCPMSS.c
index a75240f0d42..afaebc76693 100644
--- a/net/netfilter/xt_TCPMSS.c
+++ b/net/netfilter/xt_TCPMSS.c
@@ -125,6 +125,12 @@ tcpmss_mangle_packet(struct sk_buff *skb,
skb_put(skb, TCPOLEN_MSS);
+ /* RFC 879 states that the default MSS is 536 without specific
+ * knowledge that the destination host is prepared to accept larger.
+ * Since no MSS was provided, we MUST NOT set a value > 536.
+ */
+ newmss = min(newmss, (u16)536);
+
opt = (u_int8_t *)tcph + sizeof(struct tcphdr);
memmove(opt + TCPOLEN_MSS, opt, tcplen - sizeof(struct tcphdr));