Date: Sun, 6 Jul 2008 19:30:27 +0200 (CEST) From: Jilles Tjoelker <jilles@stack.nl> To: FreeBSD-gnats-submit@FreeBSD.org Subject: kern/125338: [PATCH] expand_number(3) silently truncates numeric part on i386 Message-ID: <20080706173027.62ABE33C7F@turtle.stack.nl> Resent-Message-ID: <200807061740.m66He2BC011425@freefall.freebsd.org>
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>Number: 125338
>Category: kern
>Synopsis: [PATCH] expand_number(3) silently truncates numeric part on i386
>Confidential: no
>Severity: serious
>Priority: medium
>Responsible: freebsd-bugs
>State: open
>Quarter:
>Keywords:
>Date-Required:
>Class: sw-bug
>Submitter-Id: current-users
>Arrival-Date: Sun Jul 06 17:40:02 UTC 2008
>Closed-Date:
>Last-Modified:
>Originator: Jilles Tjoelker
>Release: FreeBSD 7.0-STABLE i386
>Organization:
MCGV Stack
>Environment:
System: FreeBSD turtle.stack.nl 7.0-STABLE FreeBSD 7.0-STABLE #0: Tue May 20 22:43:27 CEST 2008 root@snail.stack.nl:/sabretooth.mnt/sources/6.x/i386/obj/sabretooth.mnt/sources/7.x/src/sys/STACK-SMP i386
problem present in -CURRENT sources as well
>Description:
On i386, if the numeric part of the string passed to expand_number(3) does
not fit in 32 bits, e.g. "5368709120k" it is truncated.
>How-To-Repeat:
Detailed how-to-repeat from Alexandre Sunny Kovalenko:
sunny:RabbitsDen>./expand_number 5368709120k
Result is 1099511627776
sunny:RabbitsDen>./expand_number 5120G
Result is 5497558138880
sunny:RabbitsDen>
The expected result is 5497558138880 for both.
test program (needs to be linked with -lutil)
#include <ctype.h>
#include <sys/types.h>
#include <inttypes.h>
#include <errno.h>
#include <libutil.h>
#include <stdio.h>
#include <stdlib.h>
int main(int argc, char *argv[])
{
if(argc != 2)
{
fprintf(stderr, "Usage: %s <number>\n", argv[0]);
exit(1);
}
errno = 0;
intmax_t result;
if(expand_number(argv[1], &result) || errno)
{
perror("Expand number");
exit(1);
}
printf("Result is %jd\n", result);
exit(0);
}
>Fix:
The problem occurs because src/lib/libutil/expand_number.c does not include
the necessary header <inttypes.h> for calling strtoimax(3). The file is
compiled without compiler warnings, so the bug shows up as wrong
behaviour.
Adding #include <inttypes.h> fixes it.
The file is slightly changed in CURRENT but the same patch should apply.
--- expand_number.patch begins here ---
--- src/lib/libutil/expand_number.c.orig 2007-09-05 16:27:13.000000000 +0200
+++ src/lib/libutil/expand_number.c 2008-07-06 13:11:02.766238000 +0200
@@ -33,6 +33,7 @@
#include <errno.h>
#include <libutil.h>
#include <stdint.h>
+#include <inttypes.h>
/*
* Convert an expression of the following forms to a int64_t.
--- expand_number.patch ends here ---
>Release-Note:
>Audit-Trail:
>Unformatted:
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