diff options
| author | Jozsef Kadlecsik <kadlec@netfilter.org> | 2023-09-19 21:04:45 +0300 |
|---|---|---|
| committer | Florian Westphal <fw@strlen.de> | 2023-09-20 11:35:24 +0300 |
| commit | 7433b6d2afd512d04398c73aa984d1e285be125b (patch) | |
| tree | c90fd10963400937c718053a2be2f74face6d063 /net | |
| parent | cf5000a7787cbc10341091d37245a42c119d26c5 (diff) | |
| download | linux-7433b6d2afd512d04398c73aa984d1e285be125b.tar.xz | |
netfilter: ipset: Fix race between IPSET_CMD_CREATE and IPSET_CMD_SWAP
Kyle Zeng reported that there is a race between IPSET_CMD_ADD and IPSET_CMD_SWAP
in netfilter/ip_set, which can lead to the invocation of `__ip_set_put` on a
wrong `set`, triggering the `BUG_ON(set->ref == 0);` check in it.
The race is caused by using the wrong reference counter, i.e. the ref counter instead
of ref_netlink.
Fixes: 24e227896bbf ("netfilter: ipset: Add schedule point in call_ad().")
Reported-by: Kyle Zeng <zengyhkyle@gmail.com>
Closes: https://lore.kernel.org/netfilter-devel/ZPZqetxOmH+w%2Fmyc@westworld/#r
Tested-by: Kyle Zeng <zengyhkyle@gmail.com>
Signed-off-by: Jozsef Kadlecsik <kadlec@netfilter.org>
Signed-off-by: Florian Westphal <fw@strlen.de>
Diffstat (limited to 'net')
| -rw-r--r-- | net/netfilter/ipset/ip_set_core.c | 12 |
1 files changed, 10 insertions, 2 deletions
diff --git a/net/netfilter/ipset/ip_set_core.c b/net/netfilter/ipset/ip_set_core.c index e564b5174261..35d2f9c9ada0 100644 --- a/net/netfilter/ipset/ip_set_core.c +++ b/net/netfilter/ipset/ip_set_core.c @@ -683,6 +683,14 @@ __ip_set_put(struct ip_set *set) * a separate reference counter */ static void +__ip_set_get_netlink(struct ip_set *set) +{ + write_lock_bh(&ip_set_ref_lock); + set->ref_netlink++; + write_unlock_bh(&ip_set_ref_lock); +} + +static void __ip_set_put_netlink(struct ip_set *set) { write_lock_bh(&ip_set_ref_lock); @@ -1693,11 +1701,11 @@ call_ad(struct net *net, struct sock *ctnl, struct sk_buff *skb, do { if (retried) { - __ip_set_get(set); + __ip_set_get_netlink(set); nfnl_unlock(NFNL_SUBSYS_IPSET); cond_resched(); nfnl_lock(NFNL_SUBSYS_IPSET); - __ip_set_put(set); + __ip_set_put_netlink(set); } ip_set_lock(set); |