From: Davidlohr Bueso <dave@gnu.org>
Date: Fri, 5 Oct 2012 00:13:18 +0000 (-0700)
Subject: lib/gcd.c: prevent possible div by 0
X-Git-Tag: v3.2.32~42
X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=0ae961fe09b82f5b073420233bca2475a814d75b;p=karo-tx-linux.git

lib/gcd.c: prevent possible div by 0

commit e96875677fb2b7cb739c5d7769824dff7260d31d upstream.

Account for all properties when a and/or b are 0:
gcd(0, 0) = 0
gcd(a, 0) = a
gcd(0, b) = b

Fixes no known problems in current kernels.

Signed-off-by: Davidlohr Bueso <dave@gnu.org>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
---

diff --git a/lib/gcd.c b/lib/gcd.c
index f879033d9822..433d89bd9d89 100644
--- a/lib/gcd.c
+++ b/lib/gcd.c
@@ -9,6 +9,9 @@ unsigned long gcd(unsigned long a, unsigned long b)
 
 	if (a < b)
 		swap(a, b);
+
+	if (!b)
+		return a;
 	while ((r = a % b) != 0) {
 		a = b;
 		b = r;