5.15-stable review patch. If anyone has any objections, please let me know.
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From: Phil Sutter phil@nwl.cc
[ Upstream commit 70b6f46a4ed8bd56c85ffff22df91e20e8c85e33 ]
With CONFIG_PROVE_LOCKING, when creating a set of type bitmap:ip, adding it to a set of type list:set and populating it from iptables SET target triggers a kernel warning:
| WARNING: possible recursive locking detected | 6.12.0-rc7-01692-g5e9a28f41134-dirty #594 Not tainted | -------------------------------------------- | ping/4018 is trying to acquire lock: | ffff8881094a6848 (&set->lock){+.-.}-{2:2}, at: ip_set_add+0x28c/0x360 [ip_set] | | but task is already holding lock: | ffff88811034c048 (&set->lock){+.-.}-{2:2}, at: ip_set_add+0x28c/0x360 [ip_set]
This is a false alarm: ipset does not allow nested list:set type, so the loop in list_set_kadd() can never encounter the outer set itself. No other set type supports embedded sets, so this is the only case to consider.
To avoid the false report, create a distinct lock class for list:set type ipset locks.
Fixes: f830837f0eed ("netfilter: ipset: list:set set type support") Signed-off-by: Phil Sutter phil@nwl.cc Signed-off-by: Pablo Neira Ayuso pablo@netfilter.org Signed-off-by: Sasha Levin sashal@kernel.org --- net/netfilter/ipset/ip_set_list_set.c | 3 +++ 1 file changed, 3 insertions(+)
diff --git a/net/netfilter/ipset/ip_set_list_set.c b/net/netfilter/ipset/ip_set_list_set.c index 902ff2f3bc72..5cc35b553a04 100644 --- a/net/netfilter/ipset/ip_set_list_set.c +++ b/net/netfilter/ipset/ip_set_list_set.c @@ -611,6 +611,8 @@ init_list_set(struct net *net, struct ip_set *set, u32 size) return true; }
+static struct lock_class_key list_set_lockdep_key; + static int list_set_create(struct net *net, struct ip_set *set, struct nlattr *tb[], u32 flags) @@ -627,6 +629,7 @@ list_set_create(struct net *net, struct ip_set *set, struct nlattr *tb[], if (size < IP_SET_LIST_MIN_SIZE) size = IP_SET_LIST_MIN_SIZE;
+ lockdep_set_class(&set->lock, &list_set_lockdep_key); set->variant = &set_variant; set->dsize = ip_set_elem_len(set, tb, sizeof(struct set_elem), __alignof__(struct set_elem));