redonkable
/
alistair23-linux
1
0
Fork 0
Code Releases Activity

netfilter: ipt_CLUSTERIP: fix out-of-bounds accesses in clusterip_tg_check() 

Commit 136e92bbec switched local_nodes from an array to a bitmask
but did not add proper bounds checks. As the result
clusterip_config_init_nodelist() can both over-read
ipt_clusterip_tgt_info.local_nodes and over-write
clusterip_config.local_nodes.

Add bounds checks for both.

Fixes: 136e92bbec ("[NETFILTER] CLUSTERIP: use a bitmap to store node responsibility data")
Signed-off-by: Dmitry Vyukov <dvyukov@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
hifive-unleashed-5.1
Dmitry Vyukov 2018-01-30 15:21:34 +01:00 committed by Pablo Neira Ayuso
parent 1e98ffea5a
commit 1a38956cce
1 changed files with 13 additions and 3 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

16
net/ipv4/netfilter/ipt_CLUSTERIP.c
View File

@ -431,7 +431,7 @@ static int clusterip_tg_check(const struct xt_tgchk_param *par)
struct ipt_clusterip_tgt_info *cipinfo = par->targinfo;
const struct ipt_entry *e = par->entryinfo;
struct clusterip_config *config;
int ret;
int ret, i;
if (par->nft_compat) {
pr_err("cannot use CLUSTERIP target from nftables compat\n");
@ -450,8 +450,18 @@ static int clusterip_tg_check(const struct xt_tgchk_param *par)
pr_info("Please specify destination IP\n");
return -EINVAL;
}
/* FIXME: further sanity checks */
if (cipinfo->num_local_nodes > ARRAY_SIZE(cipinfo->local_nodes)) {
pr_info("bad num_local_nodes %u\n", cipinfo->num_local_nodes);
return -EINVAL;
}
for (i = 0; i < cipinfo->num_local_nodes; i++) {
if (cipinfo->local_nodes[i] - 1 >=
sizeof(config->local_nodes) * 8) {
pr_info("bad local_nodes[%d] %u\n",
i, cipinfo->local_nodes[i]);
return -EINVAL;
}
}
config = clusterip_config_find_get(par->net, e->ip.dst.s_addr, 1);
if (!config) {