diff options
| author | Eric Dumazet <edumazet@google.com> | 2017-09-01 14:03:32 -0700 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2017-09-01 17:33:17 -0700 |
| commit | 4cc5b44b29a9de9b3f841efedaa3f769066c63cc (patch) | |
| tree | 2a98212b93c7c09a10a29c57754f3bc8cde99627 | |
| parent | bbd9644e84f68587ed136c7e1c56e454c26231ff (diff) | |
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: b145425f269a ("inetpeer: remove AVL implementation in favor of RB tree")
Reported-by: John Sperbeck <jsperbeck@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
| -rw-r--r-- | net/ipv4/inetpeer.c | 9 |
1 files changed, 6 insertions, 3 deletions
diff --git a/net/ipv4/inetpeer.c b/net/ipv4/inetpeer.c index 337ad41bb80a..e7eb590c86ce 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) { |