Date: Thu, 26 Aug 2010 05:50:05 GMT From: Garrett Cooper <gcooper@FreeBSD.org> To: freebsd-gnats-submit@FreeBSD.org Subject: kern/149980: [PATCH] negative value integer to nanosleep(2) should fail with EINVAL Message-ID: <201008260550.o7Q5o5hf065099@www.freebsd.org> Resent-Message-ID: <201008260600.o7Q60Hcs093370@freefall.freebsd.org>
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>Number: 149980
>Category: kern
>Synopsis: [PATCH] negative value integer to nanosleep(2) should fail with EINVAL
>Confidential: no
>Severity: non-critical
>Priority: medium
>Responsible: freebsd-bugs
>State: open
>Quarter:
>Keywords:
>Date-Required:
>Class: doc-bug
>Submitter-Id: current-users
>Arrival-Date: Thu Aug 26 06:00:16 UTC 2010
>Closed-Date:
>Last-Modified:
>Originator: Garrett Cooper
>Release: 9-CURRENT
>Organization:
Cisco Systems, Inc.
>Environment:
FreeBSD bayonetta.local 9.0-CURRENT FreeBSD 9.0-CURRENT #9 r211309M: Thu Aug 19 22:50:36 PDT 2010 root@bayonetta.local:/usr/obj/usr/src/sys/BAYONETTA amd64
>Description:
After some discussion with the POSIX folks, the spec doesn't discuss the tv_sec quantity, partly because the time_t value that gets plugged in for tv_sec can be positive or negative, depending on the implementation in the operating system. In FreeBSD time_t is signed, and in Linux it's unsigned.
Signedness values aside, it doesn't make sense to sleep negative time, because PCs shouldn't be traveling to the past :).
The patch clearly notes the positive real number requirement and addresses the < 0 quantity issue at the kernel level.
# BEFORE
$ ./test_nanosleep_negative_time
passed unexpectedly
# AFTER
$ ./test_nanosleep_negative_time
failed as expected
$ echo $?
0
>How-To-Repeat:
1. Compile the following program:
#include <err.h>
#include <errno.h>
#include <stdio.h>
#include <time.h>
int
main(void)
{
struct timespec rqtp;
rqtp.tv_sec = -1;
rqtp.tv_nsec = 0;
if (nanosleep(&rqtp, NULL) == -1) {
if (errno == EINVAL) {
printf("failed as expected\n");
return (0);
} else
warn("failed unexpectedly");
} else
printf("passed unexpectedly\n");
return (1);
}
2. Execute the compiled binary.
>Fix:
Patch attached with submission follows:
Index: lib/libc/sys/nanosleep.2
===================================================================
--- lib/libc/sys/nanosleep.2 (revision 211794)
+++ lib/libc/sys/nanosleep.2 (working copy)
@@ -93,6 +93,11 @@
The
.Fa rqtp
argument
+specified a second value less than zero.
+.It Bq Er EINVAL
+The
+.Fa rqtp
+argument
specified a nanosecond value less than zero
or greater than or equal to 1000 million.
.It Bq Er ENOSYS
Index: sys/kern/kern_time.c
===================================================================
--- sys/kern/kern_time.c (revision 211794)
+++ sys/kern/kern_time.c (working copy)
@@ -358,7 +358,9 @@
if (rqt->tv_nsec < 0 || rqt->tv_nsec >= 1000000000)
return (EINVAL);
- if (rqt->tv_sec < 0 || (rqt->tv_sec == 0 && rqt->tv_nsec == 0))
+ if (rqt->tv_sec < 0)
+ return (EINVAL);
+ if (rqt->tv_sec == 0 && rqt->tv_nsec == 0)
return (0);
getnanouptime(&ts);
timespecadd(&ts, rqt);
>Release-Note:
>Audit-Trail:
>Unformatted:
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