Re: Stime/Settimeofday are still broken

["David S. Miller" <davem@redhat.com>]

On Tue, 15 Jul 2003 00:40:49 -0700
"B. D. Elliott" <bde@nwlink.com> wrote:

> The problems described below still exist in -2.6.0-test1.

Ignore my previous reply, not a Sparc problem obviously
but a generic one, sorry.

Andrew, he's right, we need to fix this and his patch looks
perfectly fine.

> >Date: Wed, 18 Jun 2003 00:57:12 -0700
> >From: "B. D. Elliott" <bde@nwlink.com>
> >To: linux-kernel@vger.kernel.org
> >Subject: Sparc64-2.5.72: A Serious Time Problem
> >Mail-Followup-To: linux-kernel@vger.kernel.org
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> >Content-Disposition: inline
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> >Status: RO
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> >
> >There is a serious bug in setting time on 64-bit sparcs (and probably other
> >64-bit systems).  The symptom is that ntpdate or date set the time back to
> >1969 or 1970.  The underlying problems are that stime is broken, and any
> >settimeofday call fails with a bad fractional value.  Ntpdate falls back to
> >stime when settimeofday fails.
> >
> >The settimeofday problem is that the timeval and timespec structures are not
> >the same size.  In particular, the fractional part is an int in timeval, and
> >a long in timespec.  The stime problem is that the argument is not an int,
> >but a time_t, which is long on at least some 64-bit systems.
> >
> >The following patch appears to fix this on my sparc64.
> >
> >===================================================================
> >--- ./kernel/time.c.orig	2003-06-16 22:36:04.000000000 -0700
> >+++ ./kernel/time.c	2003-06-18 00:00:43.000000000 -0700
> >@@ -66,7 +66,7 @@
> >  * architectures that need it).
> >  */
> >  
> >-asmlinkage long sys_stime(int * tptr)
> >+asmlinkage long sys_stime(time_t * tptr)
> > {
> > 	struct timespec tv;
> > 
> >@@ -162,13 +162,15 @@
> > 
> > asmlinkage long sys_settimeofday(struct timeval __user *tv, struct timezone __user *tz)
> > {
> >+	struct timeval user_tv;
> > 	struct timespec	new_tv;
> > 	struct timezone new_tz;
> > 
> > 	if (tv) {
> >-		if (copy_from_user(&new_tv, tv, sizeof(*tv)))
> >+		if (copy_from_user(&user_tv, tv, sizeof(*tv)))
> > 			return -EFAULT;
> >-		new_tv.tv_nsec *= NSEC_PER_USEC;
> >+		new_tv.tv_sec = user_tv.tv_sec;
> >+		new_tv.tv_nsec = user_tv.tv_usec * NSEC_PER_USEC;
> > 	}
> > 	if (tz) {
> > 		if (copy_from_user(&new_tz, tz, sizeof(*tz)))
> >===================================================================
> 
> -- 
> B. D. Elliott   bde@nwlink.com
> -
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