Commit 63da7a2b authored Jul 24, 2022 by Xin Xiong Committed by Greg Kroah-Hartman Sep 05, 2022

xfrm: fix refcount leak in __xfrm_policy_check()



[ Upstream commit 9c9cb23e00ddf45679b21b4dacc11d1ae7961ebe ]

The issue happens on an error path in __xfrm_policy_check(). When the
fetching process of the object `pols[1]` fails, the function simply
returns 0, forgetting to decrement the reference count of `pols[0]`,
which is incremented earlier by either xfrm_sk_policy_lookup() or
xfrm_policy_lookup(). This may result in memory leaks.

Fix it by decreasing the reference count of `pols[0]` in that path.

Fixes: 134b0fc5 ("IPsec: propagate security module errors up from flow_cache_lookup")
Signed-off-by: Xin Xiong <xiongx18@fudan.edu.cn>
Signed-off-by: Xin Tan <tanxin.ctf@gmail.com>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

parent a9f94dc4

net/xfrm/xfrm_policy.c

+1 −0

Original line number	Diff line number	Diff line
		@@ -3619,6 +3619,7 @@ int __xfrm_policy_check(struct sock sk, int dir, struct sk_buff skb,
		if (pols[1]) {
		if (IS_ERR(pols[1])) {
		XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR);
		xfrm_pol_put(pols[0]);
		return 0;
		}
		pols[1]->curlft.use_time = ktime_get_real_seconds();