Subject: [PATCH 03/25] ipv6: fix useless rol32 call on hash

From: Colin Ian King <[email-masked]>
Date: Tue, 17 Jul 2018 17:12:39 +0100

[ Upstream commit 169dc027fb02492ea37a0575db6a658cf922b854 ]

The rol32 call is currently rotating hash but the rol'd value is
being discarded. I believe the current code is incorrect and hash
should be assigned the rotated value returned from rol32.

Thanks to David Lebrun for spotting this.

Signed-off-by: Colin Ian King <[email-masked]>
Signed-off-by: David S. Miller <[email-masked]>
---
 include/net/ipv6.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/include/net/ipv6.h b/include/net/ipv6.h
index a406f2e8680a..aeebbbb9e0bd 100644
--- a/include/net/ipv6.h
+++ b/include/net/ipv6.h
@@ -829,7 +829,7 @@ static inline __be32 ip6_make_flowlabel(struct net *net, struct sk_buff *skb,
 	 * to minimize possbility that any useful information to an
 	 * attacker is leaked. Only lower 20 bits are relevant.
 	 */
-	rol32(hash, 16);
+	hash = rol32(hash, 16);
 
 	flowlabel = (__force __be32)hash & IPV6_FLOWLABEL_MASK;
 
-- 
2.17.1