[PATCH] Re: [2.6.0, pktgen] divide-by-zero
From: Jörn Engel <hidden>
Date: 2004-01-18 15:48:28
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On Wed, 31 December 2003 06:13:16 -0500, Lennert Buytenhek wrote:
When generating packets with pktgen with count=10, I get a divide-by-zero oops in inject(). Line 273 in net/core/pktgen.c seems unsafe: __u64 pps = (__u32)(info->sofar * 1000) / ((__u32)(total) / 1000); What if total < 1000 ?
Since noone else seemed to care, try this patch. Against -test11, yeah, I'm lazy again. Jörn -- Time? What's that? Time is only worth what you do with it. -- Theo de Raadt
--- old/net/core/pktgen.c 2003-11-26 21:44:47.000000000 +0100
+++ new/net/core/pktgen.c 2004-01-18 16:27:10.000000000 +0100@@ -720,7 +720,9 @@ { char *p = info->result; - __u64 pps = (__u32)(info->sofar * 1000) / ((__u32)(total) / 1000); + __u32 safe_total = (__u32)(total) / 1000; + safe_total += 1 - (!!safe_total); /* avoid divide-by-zero */ + __u64 pps = (__u32)(info->sofar * 1000) / safe_total; __u64 bps = pps * 8 * (info->pkt_size + 4); /* take 32bit ethernet CRC into account */ p += sprintf(p, "OK: %llu(c%llu+d%llu) usec, %llu (%dbyte,%dfrags) %llupps %lluMb/sec (%llubps) errors: %llu", (unsigned long long) total,