This is a note to let you know that I've just added the patch titled xfrm: fix refcount leak in __xfrm_policy_check() to the 5.10-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: xfrm-fix-refcount-leak-in-__xfrm_policy_check.patch and it can be found in the queue-5.10 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit b160006a887ff63c1503626ead78c749d11b6d47 Author: Xin Xiong <xiongx18@xxxxxxxxxxxx> Date: Sun Jul 24 17:55:58 2022 +0800 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: 134b0fc544ba ("IPsec: propagate security module errors up from flow_cache_lookup") Signed-off-by: Xin Xiong <xiongx18@xxxxxxxxxxxx> Signed-off-by: Xin Tan <tanxin.ctf@xxxxxxxxx> Signed-off-by: Steffen Klassert <steffen.klassert@xxxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/net/xfrm/xfrm_policy.c b/net/xfrm/xfrm_policy.c index 603b05ed7eb4c..2cd66f3e52386 100644 --- a/net/xfrm/xfrm_policy.c +++ b/net/xfrm/xfrm_policy.c @@ -3641,6 +3641,7 @@ 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();