[PATCH AUTOSEL 4.14 16/44] netfilter: ipset: Fix rename concurrency with listing

[Sasha Levin]

From: Jozsef Kadlecsik <kadlec@xxxxxxxxxxxxx>

[ Upstream commit 6c1f7e2c1b96ab9b09ac97c4df2bd9dc327206f6 ]

Shijie Luo reported that when stress-testing ipset with multiple concurrent
create, rename, flush, list, destroy commands, it can result

ipset <version>: Broken LIST kernel message: missing DATA part!

error messages and broken list results. The problem was the rename operation
was not properly handled with respect of listing. The patch fixes the issue.

Reported-by: Shijie Luo <luoshijie1@xxxxxxxxxx>
Signed-off-by: Jozsef Kadlecsik <kadlec@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
 net/netfilter/ipset/ip_set_core.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/netfilter/ipset/ip_set_core.c b/net/netfilter/ipset/ip_set_core.c
index a3f1dc7cf5382..dbf17d3596a69 100644
--- a/net/netfilter/ipset/ip_set_core.c
+++ b/net/netfilter/ipset/ip_set_core.c
@@ -1128,7 +1128,7 @@ static int ip_set_rename(struct net *net, struct sock *ctnl,
 		return -ENOENT;
 
 	write_lock_bh(&ip_set_ref_lock);
-	if (set->ref != 0) {
+	if (set->ref != 0 || set->ref_netlink != 0) {
 		ret = -IPSET_ERR_REFERENCED;
 		goto out;
 	}
-- 
2.20.1