[EBTABLES]: Deal with the worst-case behaviour in loop checks.

No need to revisit a chain we'd already finished with during
the check for current hook.  It's either instant loop (which
we'd just detected) or a duplicate work.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 3 insertions, 1 deletions

diff --git a/net/bridge/netfilter/ebtables.c b/net/bridge/netfilter/ebtables.c
index 6ab7674ea454..46ab9b759269 100644
--- a/net/bridge/netfilter/ebtables.c
+++ b/net/bridge/netfilter/ebtables.c
@@ -717,7 +717,9 @@ static int check_chainloops(struct ebt_entries *chain, struct ebt_cl_stack *cl_s
                                 BUGPRINT("loop\n");
                                 return -1;
                         }
-                        /* this can't be 0, so the above test is correct */
+                        if (cl_s[i].hookmask & (1 << hooknr))
+                                goto letscontinue;
+                        /* this can't be 0, so the loop test is correct */
                         cl_s[i].cs.n = pos + 1;
                         pos = 0;
                         cl_s[i].cs.e = ((void *)e + e->next_offset);