flow_dissector: Fix function argument ordering dependency (de4c1f8b) · Commits · 戴 / test

Commit ("flowi: Abstract out functions to get flow hash based on flowi") introduced a bug in __skb_set_sw_hash where we require a dependency on evaluating arguments in a function in order. There is no such ordering enforced in C, so this incorrect. This patch fixes that by splitting out the arguments. This bug was found via a compiler warning that keys may be uninitialized. Signed-off-by:

Tom Herbert <tom@herbertland.com> Signed-off-by:

David S. Miller <davem@davemloft.net>

include/linux/skbuff.h

+4 −4

Original line number	Original line	Diff line number	Diff line
	@@ -1035,9 +1035,9 @@ static inline __u32 skb_get_hash_flowi6(struct sk_buff skb, struct flowi6 fl6)
	{		{
	if (!skb->l4_hash && !skb->sw_hash) {		if (!skb->l4_hash && !skb->sw_hash) {
	struct flow_keys keys;		struct flow_keys keys;
			__u32 hash = __get_hash_from_flowi6(fl6, &keys);

	__skb_set_sw_hash(skb, __get_hash_from_flowi6(fl6, &keys),		__skb_set_sw_hash(skb, hash, flow_keys_have_l4(&keys));
	flow_keys_have_l4(&keys));
	}		}

	return skb->hash;		return skb->hash;
	@@ -1049,9 +1049,9 @@ static inline __u32 skb_get_hash_flowi4(struct sk_buff skb, struct flowi4 fl4)
	{		{
	if (!skb->l4_hash && !skb->sw_hash) {		if (!skb->l4_hash && !skb->sw_hash) {
	struct flow_keys keys;		struct flow_keys keys;
			__u32 hash = __get_hash_from_flowi4(fl4, &keys);

	__skb_set_sw_hash(skb, __get_hash_from_flowi4(fl4, &keys),		__skb_set_sw_hash(skb, hash, flow_keys_have_l4(&keys));
	flow_keys_have_l4(&keys));
	}		}

	return skb->hash;		return skb->hash;

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