From e95b42ea54d2989659232560a9932b676e801604 Mon Sep 17 00:00:00 2001
From: Con Kolivas <kernel@kolivas.org>
Date: Sat, 2 Nov 2013 08:46:13 +1100
Subject: [PATCH] Add a sanity check to avoid divide by zero crashes in
 set_target

---
 cgminer.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/cgminer.c b/cgminer.c
index b58476d5..95de19cd 100644
--- a/cgminer.c
+++ b/cgminer.c
@@ -5926,6 +5926,12 @@ void set_target(unsigned char *dest_target, double diff)
 	uint64_t *data64, h64;
 	double d64, dcut64;
 
+	if (unlikely(diff == 0.0)) {
+		/* This shouldn't happen but best we check to prevent a crash */
+		applog(LOG_ERR, "Diff zero passed to set_target");
+		diff = 1.0;
+	}
+
 	d64 = truediffone;
 	if (opt_scrypt)
 		d64 *= (double)65536;