[PATCH AUTOSEL 5.2 057/123] netfilter: ipset: Fix rename concurrency with listing

From: Sasha Levin
Date: Tue Aug 13 2019 - 22:37:15 EST


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 16afa0df4004d..e103c875383a5 100644
--- a/net/netfilter/ipset/ip_set_core.c
+++ b/net/netfilter/ipset/ip_set_core.c
@@ -1161,7 +1161,7 @@ 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