From 635c223cfa05af9523146b2f37e119d945f449ae Mon Sep 17 00:00:00 2001 From: Gao Feng Date: Wed, 31 Aug 2016 14:15:05 +0800 Subject: [PATCH] rps: flow_dissector: Fix uninitialized flow_keys used in __skb_get_hash possibly The original codes depend on that the function parameters are evaluated from left to right. But the parameter's evaluation order is not defined in C standard actually. When flow_keys_have_l4(&keys) is invoked before ___skb_get_hash(skb, &keys, hashrnd) with some compilers or environment, the keys passed to flow_keys_have_l4 is not initialized. Fixes: 6db61d79c1e1 ("flow_dissector: Ignore flow dissector return value from ___skb_get_hash") Acked-by: Eric Dumazet Signed-off-by: Gao Feng Signed-off-by: David S. Miller --- net/core/flow_dissector.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/net/core/flow_dissector.c b/net/core/flow_dissector.c index 61ad43f61c5e..52742a02814f 100644 --- a/net/core/flow_dissector.c +++ b/net/core/flow_dissector.c @@ -680,11 +680,13 @@ EXPORT_SYMBOL_GPL(__skb_get_hash_symmetric); void __skb_get_hash(struct sk_buff *skb) { struct flow_keys keys; + u32 hash; __flow_hash_secret_init(); - __skb_set_sw_hash(skb, ___skb_get_hash(skb, &keys, hashrnd), - flow_keys_have_l4(&keys)); + hash = ___skb_get_hash(skb, &keys, hashrnd); + + __skb_set_sw_hash(skb, hash, flow_keys_have_l4(&keys)); } EXPORT_SYMBOL(__skb_get_hash); -- 2.20.1