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| author | Oliver Smith <oliver@8.c.9.b.0.7.4.0.1.0.0.2.ip6.arpa> | 2013-09-16 20:30:57 +0200 |
|---|---|---|
| committer | Jozsef Kadlecsik <kadlec@blackhole.kfki.hu> | 2013-09-16 20:36:09 +0200 |
| commit | 2cf55125c64d64cc106e204d53b107094762dfdf (patch) | |
| tree | 01562dc48e3acb3bc021dc2930180fedfefb8c77 /net | |
| parent | netfilter: ipset: Validate the set family and not the set type family at swap... (diff) | |
| download | linux-2cf55125c64d64cc106e204d53b107094762dfdf.tar.xz linux-2cf55125c64d64cc106e204d53b107094762dfdf.zip | |
netfilter: ipset: Fix serious failure in CIDR tracking
This fixes a serious bug affecting all hash types with a net element -
specifically, if a CIDR value is deleted such that none of the same size
exist any more, all larger (less-specific) values will then fail to
match. Adding back any prefix with a CIDR equal to or more specific than
the one deleted will fix it.
Steps to reproduce:
ipset -N test hash:net
ipset -A test 1.1.0.0/16
ipset -A test 2.2.2.0/24
ipset -T test 1.1.1.1 #1.1.1.1 IS in set
ipset -D test 2.2.2.0/24
ipset -T test 1.1.1.1 #1.1.1.1 IS NOT in set
This is due to the fact that the nets counter was unconditionally
decremented prior to the iteration that shifts up the entries. Now, we
first check if there is a proceeding entry and if not, decrement it and
return. Otherwise, we proceed to iterate and then zero the last element,
which, in most cases, will already be zero.
Signed-off-by: Oliver Smith <oliver@8.c.9.b.0.7.4.0.1.0.0.2.ip6.arpa>
Signed-off-by: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
Diffstat (limited to 'net')
| -rw-r--r-- | net/netfilter/ipset/ip_set_hash_gen.h | 28 |
1 files changed, 16 insertions, 12 deletions
diff --git a/net/netfilter/ipset/ip_set_hash_gen.h b/net/netfilter/ipset/ip_set_hash_gen.h index 57beb1762b2d..707bc520d629 100644 --- a/net/netfilter/ipset/ip_set_hash_gen.h +++ b/net/netfilter/ipset/ip_set_hash_gen.h @@ -325,18 +325,22 @@ mtype_add_cidr(struct htype *h, u8 cidr, u8 nets_length) static void mtype_del_cidr(struct htype *h, u8 cidr, u8 nets_length) { - u8 i, j; - - for (i = 0; i < nets_length - 1 && h->nets[i].cidr != cidr; i++) - ; - h->nets[i].nets--; - - if (h->nets[i].nets != 0) - return; - - for (j = i; j < nets_length - 1 && h->nets[j].nets; j++) { - h->nets[j].cidr = h->nets[j + 1].cidr; - h->nets[j].nets = h->nets[j + 1].nets; + u8 i, j, net_end = nets_length - 1; + + for (i = 0; i < nets_length; i++) { + if (h->nets[i].cidr != cidr) + continue; + if (h->nets[i].nets > 1 || i == net_end || + h->nets[i + 1].nets == 0) { + h->nets[i].nets--; + return; + } + for (j = i; j < net_end && h->nets[j].nets; j++) { + h->nets[j].cidr = h->nets[j + 1].cidr; + h->nets[j].nets = h->nets[j + 1].nets; + } + h->nets[j].nets = 0; + return; } } #endif |