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

Commit 4cc5b44b authored by Eric Dumazet's avatar Eric Dumazet Committed by David S. Miller
Browse files

inetpeer: fix RCU lookup() 



Excess of seafood or something happened while I cooked the commit
adding RB tree to inetpeer.

Of course, RCU rules need to be respected or bad things can happen.

In this particular loop, we need to read *pp once per iteration, not
twice.

Fixes: b145425f ("inetpeer: remove AVL implementation in favor of RB tree")
Reported-by: default avatarJohn Sperbeck <jsperbeck@google.com>
Signed-off-by: default avatarEric Dumazet <edumazet@google.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent bbd9644e

net/ipv4/inetpeer.c

+6 −3
Original line number Diff line number Diff line
@@ -102,15 +102,18 @@ static struct inet_peer *lookup(const struct inetpeer_addr *daddr, 
				struct rb_node **parent_p,

				struct rb_node ***pp_p)

{

	struct rb_node **pp, *parent;

	struct rb_node **pp, *parent, *next;

	struct inet_peer *p;



	pp = &base->rb_root.rb_node;

	parent = NULL;

	while (*pp) {

	while (1) {

		int cmp;



		parent = rcu_dereference_raw(*pp);

		next = rcu_dereference_raw(*pp);

		if (!next)

			break;

		parent = next;

		p = rb_entry(parent, struct inet_peer, rb_node);

		cmp = inetpeer_addr_cmp(daddr, &p->daddr);

		if (cmp == 0) {