From: Patrick McHardy <kaber@trash.net>
Date: Wed, 6 Feb 2008 00:19:59 +0000 (-0800)
Subject: [NET_SCHED]: cls_flow: fix key mask validity check
X-Git-Tag: firefly_0821_release~23011^2~6
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=4f25049106e0507ff21a9e1fc0645d849e19faf0;p=firefly-linux-kernel-4.4.55.git

[NET_SCHED]: cls_flow: fix key mask validity check

Since we're using fls(), we need to check whether the value is
non-zero first.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
---

diff --git a/net/sched/cls_flow.c b/net/sched/cls_flow.c
index 8d7698621f0a..eeb223cf14cf 100644
--- a/net/sched/cls_flow.c
+++ b/net/sched/cls_flow.c
@@ -402,12 +402,13 @@ static int flow_change(struct tcf_proto *tp, unsigned long base,
 
 	if (tb[TCA_FLOW_KEYS]) {
 		keymask = nla_get_u32(tb[TCA_FLOW_KEYS]);
-		if (fls(keymask) - 1 > FLOW_KEY_MAX)
-			return -EOPNOTSUPP;
 
 		nkeys = hweight32(keymask);
 		if (nkeys == 0)
 			return -EINVAL;
+
+		if (fls(keymask) - 1 > FLOW_KEY_MAX)
+			return -EOPNOTSUPP;
 	}
 
 	err = tcf_exts_validate(tp, tb, tca[TCA_RATE], &e, &flow_ext_map);