From: Colin Ian King <colin.king@canonical.com>
Date: Tue, 17 Jul 2018 15:52:54 +0000 (+0100)
Subject: ipv6: sr: fix useless rol32 call on hash
X-Git-Tag: v4.19~602^2~7
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=3ee593adbbb46d9e1bb1320915943926f4744483;p=platform%2Fkernel%2Flinux-rpi3.git

ipv6: sr: fix useless rol32 call on hash

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.

Detected by CoverityScan, CID#1468411 ("Useless call")

Fixes: b5facfdba14c ("ipv6: sr: Compute flowlabel for outer IPv6 header of seg6 encap mode")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Acked-by: dlebrun@google.com
Signed-off-by: David S. Miller <davem@davemloft.net>
---

diff --git a/net/ipv6/seg6_iptunnel.c b/net/ipv6/seg6_iptunnel.c
index 19ccf0d..a8854dd 100644
--- a/net/ipv6/seg6_iptunnel.c
+++ b/net/ipv6/seg6_iptunnel.c
@@ -101,7 +101,7 @@ static __be32 seg6_make_flowlabel(struct net *net, struct sk_buff *skb,
 
 	if (do_flowlabel > 0) {
 		hash = skb_get_hash(skb);
-		rol32(hash, 16);
+		hash = rol32(hash, 16);
 		flowlabel = (__force __be32)hash & IPV6_FLOWLABEL_MASK;
 	} else if (!do_flowlabel && skb->protocol == htons(ETH_P_IPV6)) {
 		flowlabel = ip6_flowlabel(inner_hdr);