5.4-stable review patch. If anyone has any objections, please let me know.
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From: Hyunwoo Kim v4bel@theori.io
[ 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: 11efd5cb04a1 ("openvswitch: Support conntrack zone limit") Signed-off-by: Hyunwoo Kim v4bel@theori.io Reviewed-by: Eric Dumazet edumazet@google.com Reviewed-by: Aaron Conole aconole@redhat.com Link: https://lore.kernel.org/r/ZiYvzQN/Ry5oeFQW@v4bel-B760M-AORUS-ELITE-AX Signed-off-by: Jakub Kicinski kuba@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- net/openvswitch/conntrack.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/net/openvswitch/conntrack.c b/net/openvswitch/conntrack.c index 90c5f53007281..48522c688c3e6 100644 --- a/net/openvswitch/conntrack.c +++ b/net/openvswitch/conntrack.c @@ -1897,9 +1897,9 @@ 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(ovs_net->ct_limit_info->limits);