diff options
| author | Patrick McHardy <kaber@trash.net> | 2009-04-06 17:31:29 +0200 |
|---|---|---|
| committer | Chris Wright <chrisw@sous-sol.org> | 2009-04-27 10:36:58 -0700 |
| commit | 6bc1b5deb47f0fc3d697abd2fcd417618cf07e3f (patch) | |
| tree | 3b9db7780cb5f6f2fdac8bfc7b1b7c845e5cc6e4 | |
| parent | 3b3e59f78d3bf0e0818a9b759484138d4300a72e (diff) | |
| download | lwn-6bc1b5deb47f0fc3d697abd2fcd417618cf07e3f.tar.gz lwn-6bc1b5deb47f0fc3d697abd2fcd417618cf07e3f.zip | |
netfilter: {ip, ip6, arp}_tables: fix incorrect loop detection
upstream commit: 1f9352ae2253a97b07b34dcf16ffa3b4ca12c558
Commit e1b4b9f ([NETFILTER]: {ip,ip6,arp}_tables: fix exponential worst-case
search for loops) introduced a regression in the loop detection algorithm,
causing sporadic incorrectly detected loops.
When a chain has already been visited during the check, it is treated as
having a standard target containing a RETURN verdict directly at the
beginning in order to not check it again. The real target of the first
rule is then incorrectly treated as STANDARD target and checked not to
contain invalid verdicts.
Fix by making sure the rule does actually contain a standard target.
Based on patch by Francis Dupont <Francis_Dupont@isc.org>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Chris Wright <chrisw@sous-sol.org>
| -rw-r--r-- | net/ipv4/netfilter/arp_tables.c | 4 | ||||
| -rw-r--r-- | net/ipv4/netfilter/ip_tables.c | 4 | ||||
| -rw-r--r-- | net/ipv6/netfilter/ip6_tables.c | 4 |
3 files changed, 9 insertions, 3 deletions
diff --git a/net/ipv4/netfilter/arp_tables.c b/net/ipv4/netfilter/arp_tables.c index 7ea88b61cb0d..39879aef9e4e 100644 --- a/net/ipv4/netfilter/arp_tables.c +++ b/net/ipv4/netfilter/arp_tables.c @@ -374,7 +374,9 @@ static int mark_source_chains(struct xt_table_info *newinfo, && unconditional(&e->arp)) || visited) { unsigned int oldpos, size; - if (t->verdict < -NF_MAX_VERDICT - 1) { + if ((strcmp(t->target.u.user.name, + ARPT_STANDARD_TARGET) == 0) && + t->verdict < -NF_MAX_VERDICT - 1) { duprintf("mark_source_chains: bad " "negative verdict (%i)\n", t->verdict); diff --git a/net/ipv4/netfilter/ip_tables.c b/net/ipv4/netfilter/ip_tables.c index ef8b6ca068b2..ec362a344f05 100644 --- a/net/ipv4/netfilter/ip_tables.c +++ b/net/ipv4/netfilter/ip_tables.c @@ -496,7 +496,9 @@ mark_source_chains(struct xt_table_info *newinfo, && unconditional(&e->ip)) || visited) { unsigned int oldpos, size; - if (t->verdict < -NF_MAX_VERDICT - 1) { + if ((strcmp(t->target.u.user.name, + IPT_STANDARD_TARGET) == 0) && + t->verdict < -NF_MAX_VERDICT - 1) { duprintf("mark_source_chains: bad " "negative verdict (%i)\n", t->verdict); diff --git a/net/ipv6/netfilter/ip6_tables.c b/net/ipv6/netfilter/ip6_tables.c index a33485dc81cb..def375b7fad5 100644 --- a/net/ipv6/netfilter/ip6_tables.c +++ b/net/ipv6/netfilter/ip6_tables.c @@ -525,7 +525,9 @@ mark_source_chains(struct xt_table_info *newinfo, && unconditional(&e->ipv6)) || visited) { unsigned int oldpos, size; - if (t->verdict < -NF_MAX_VERDICT - 1) { + if ((strcmp(t->target.u.user.name, + IP6T_STANDARD_TARGET) == 0) && + t->verdict < -NF_MAX_VERDICT - 1) { duprintf("mark_source_chains: bad " "negative verdict (%i)\n", t->verdict); |