[patch 04/24] EBTABLES: Deal with the worst-case behaviour in loop checks.

Chris Wright
2006-12-15T01:35:10Z

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2.6.18-stable review patch. If anyone has any objections, please let us know.
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From: Al Viro <viro@zeniv.linux.org.uk>

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>
Signed-off-by: Chris Wright <chrisw@sous-sol.org>
---
net/bridge/netfilter/ebtables.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)

--- linux-2.6.18.5.orig/net/bridge/netfilter/ebtables.c
+++ linux-2.6.18.5/net/bridge/netfilter/ebtables.c
@@ -739,7 +739,9 @@ static int check_chainloops(struct ebt_e
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);

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