Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit c52fbb41 authored by Patrick McHardy's avatar Patrick McHardy Committed by David S. Miller
Browse files

[NETFILTER]: nf_conntrack_core: avoid taking nf_conntrack_lock in nf_conntrack_alter_reply 



The conntrack is unconfirmed, so we have an exclusive reference, which
means that the write_lock is definitely unneeded. A read_lock used to
be needed for the helper lookup, but since we're using RCU for helpers
now rcu_read_lock is enough.

Signed-off-by: default avatarPatrick McHardy <kaber@trash.net>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 58a3c9bb

net/netfilter/nf_conntrack_core.c

+3 −3
Original line number Diff line number Diff line
@@ -729,7 +729,6 @@ void nf_conntrack_alter_reply(struct nf_conn *ct, 
	struct nf_conn_help *help = nfct_help(ct);

	struct nf_conntrack_helper *helper;



	write_lock_bh(&nf_conntrack_lock);

	/* Should be unconfirmed, so not in hash table yet */

	NF_CT_ASSERT(!nf_ct_is_confirmed(ct));
@@ -738,8 +737,9 @@ void nf_conntrack_alter_reply(struct nf_conn *ct, 


	ct->tuplehash[IP_CT_DIR_REPLY].tuple = *newreply;

	if (ct->master || (help && help->expecting != 0))

		goto out;

		return;



	rcu_read_lock();

	helper = __nf_ct_helper_find(newreply);

	if (helper == NULL) {

		if (help)
@@ -757,7 +757,7 @@ void nf_conntrack_alter_reply(struct nf_conn *ct, 


	rcu_assign_pointer(help->helper, helper);

out:

	write_unlock_bh(&nf_conntrack_lock);

	rcu_read_unlock();

}

EXPORT_SYMBOL_GPL(nf_conntrack_alter_reply);