[PATCH AUTOSEL for 4.9 110/190] netfilter: x_tables: unlock on error in xt_find_table_lock()

From: Sasha Levin
Date: Thu Mar 08 2018 - 01:03:35 EST


From: Dan Carpenter <dan.carpenter@xxxxxxxxxx>

[ Upstream commit 7dde07e9c53617549d67dd3e1d791496d0d3868e ]

According to my static checker we should unlock here before the return.
That seems reasonable to me as well.

Fixes" b9e69e127397 ("netfilter: xtables: don't hook tables by default")
Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
Acked-by: Florian Westphal <fw@xxxxxxxxx>
Signed-off-by: Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx>
---
net/netfilter/x_tables.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/net/netfilter/x_tables.c b/net/netfilter/x_tables.c
index e47ade305a46..fdf90221b4a7 100644
--- a/net/netfilter/x_tables.c
+++ b/net/netfilter/x_tables.c
@@ -1004,8 +1004,10 @@ struct xt_table *xt_find_table_lock(struct net *net, u_int8_t af,
list_for_each_entry(t, &init_net.xt.tables[af], list) {
if (strcmp(t->name, name))
continue;
- if (!try_module_get(t->me))
+ if (!try_module_get(t->me)) {
+ mutex_unlock(&xt[af].mutex);
return NULL;
+ }

mutex_unlock(&xt[af].mutex);
if (t->table_init(net) != 0) {
--
2.14.1