From: Eric Dumazet <eduma...@google.com>
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: b145425f269a ("inetpeer: remove AVL implementation in favor of RB tree")
Reported-by: John Sperbeck <jsperb...@google.com>
Signed-off-by: Eric Dumazet <eduma...@google.com>
---
net/ipv4/inetpeer.c | 9 ++++++---
1 file changed, 6 insertions(+), 3 deletions(-)
diff --git a/net/ipv4/inetpeer.c b/net/ipv4/inetpeer.c
index
337ad41bb80a5fcd3db7ac674292c5b5d462982e..e7eb590c86ce2b33654c17c61619de74ff07bfd1
100644
--- a/net/ipv4/inetpeer.c
+++ b/net/ipv4/inetpeer.c
@@ -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) {
