Commit eaa8eb2b authored by Hyunwoo Kim's avatar Hyunwoo Kim Committed by Zhengchao Shao
Browse files

net: openvswitch: Fix Use-After-Free in ovs_ct_exit 

stable inclusion
from stable-v5.10.216
commit 35880c3fa6f8fe281a19975d2992644588ca33d3
category: bugfix
bugzilla: https://gitee.com/src-openeuler/kernel/issues/I9O0MV
CVE: CVE-2024-27395

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=35880c3fa6f8fe281a19975d2992644588ca33d3



--------------------------------

[ Upstream commit 5ea7b72d4fac2fdbc0425cd8f2ea33abe95235b2 ]

Since kfree_rcu, which is called in the hlist_for_each_entry_rcu traversal
of ovs_ct_limit_exit, is not part of the RCU read critical section, it
is possible that the RCU grace period will pass during the traversal and
the key will be free.

To prevent this, it should be changed to hlist_for_each_entry_safe.

Fixes: 11efd5cb ("openvswitch: Support conntrack zone limit")
Signed-off-by: default avatarHyunwoo Kim <v4bel@theori.io>
Reviewed-by: default avatarEric Dumazet <edumazet@google.com>
Reviewed-by: default avatarAaron Conole <aconole@redhat.com>
Link: https://lore.kernel.org/r/ZiYvzQN/Ry5oeFQW@v4bel-B760M-AORUS-ELITE-AX


Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
Signed-off-by: default avatarSasha Levin <sashal@kernel.org>
Signed-off-by: default avatarZhengchao Shao <shaozhengchao@huawei.com>
parent 04dd32cb

net/openvswitch/conntrack.c

+2 −2
Original line number Diff line number Diff line
@@ -1901,9 +1901,9 @@ static void ovs_ct_limit_exit(struct net *net, struct ovs_net *ovs_net) 
	for (i = 0; i < CT_LIMIT_HASH_BUCKETS; ++i) {

		struct hlist_head *head = &info->limits[i];

		struct ovs_ct_limit *ct_limit;

		struct hlist_node *next;



		hlist_for_each_entry_rcu(ct_limit, head, hlist_node,

					 lockdep_ovsl_is_held())

		hlist_for_each_entry_safe(ct_limit, next, head, hlist_node)

			kfree_rcu(ct_limit, rcu);

	}

	kfree(info->limits);