[PATCH] change compat shmget size arg to signed

[PATCH] change compat shmget size arg to signed

[Olaf Hering]

change second arg (the 'size') to signed to handle a size of -1.
ltp test shmget02 fails. This patch fixes it.
Oddly, we see the failure only on a POWER4 LPAR with 4.6G ram.

Signed-off-by: Olaf Hering <olh@suse.de>

 arch/powerpc/kernel/sys_ppc32.c |    2 +-
 1 files changed, 1 insertion(+), 1 deletion(-)

Index: linux-2.6.16-rc4-olh/arch/powerpc/kernel/sys_ppc32.c
===================================================================
--- linux-2.6.16-rc4-olh.orig/arch/powerpc/kernel/sys_ppc32.c
+++ linux-2.6.16-rc4-olh/arch/powerpc/kernel/sys_ppc32.c
@@ -429,7 +429,7 @@ long compat_sys_ipc(u32 call, u32 first,
 		return sys_shmdt(compat_ptr(ptr));
 	case SHMGET:
 		/* sign extend key_t */
-		return sys_shmget((int)first, second, third);
+		return sys_shmget((int)first, (int)second, third);
 	case SHMCTL:
 		/* sign extend shmid */
 		return compat_sys_shmctl((int)first, second, compat_ptr(ptr));

Re: [PATCH] change compat shmget size arg to signed

[Stephen Rothwell]

Hi Olaf,

> change second arg (the 'size') to signed to handle a size of -1.
> ltp test shmget02 fails. This patch fixes it.
> Oddly, we see the failure only on a POWER4 LPAR with 4.6G ram.
> 
> Signed-off-by: Olaf Hering <olh at suse.de>
> 
>  arch/powerpc/kernel/sys_ppc32.c |    2 +-
>  1 files changed, 1 insertion(+), 1 deletion(-)
>
> Index: linux-2.6.16-rc4-olh/arch/powerpc/kernel/sys_ppc32.c
> ===================================================================
> --- linux-2.6.16-rc4-olh.orig/arch/powerpc/kernel/sys_ppc32.c
> +++ linux-2.6.16-rc4-olh/arch/powerpc/kernel/sys_ppc32.c
> @@ -429,7 +429,7 @@ long compat_sys_ipc(u32 call, u32 first,
>  		return sys_shmdt(compat_ptr(ptr));
>  	case SHMGET:
>  		/* sign extend key_t */
> -		return sys_shmget((int)first, second, third);
> +		return sys_shmget((int)first, (int)second, third);
>  	case SHMCTL:
>  		/* sign extend shmid */
>  		return compat_sys_shmctl((int)first, second, compat_ptr(ptr));

Does the ltp test fail on a standard kernel(where SHMMAX is 0x2000000), or
only on a SLES kernel (where SHMMAX is ULONG_MAX)?

-- 
Cheers,
Stephen Rothwell                    sfr@canb.auug.org.au
http://www.canb.auug.org.au/~sfr/

Re: [PATCH] change compat shmget size arg to signed

[Olaf Hering]

 On Fri, Feb 24, Stephen Rothwell wrote:

> Does the ltp test fail on a standard kernel(where SHMMAX is 0x2000000), or
> only on a SLES kernel (where SHMMAX is ULONG_MAX)?

It fails with SLES9 and SLES10. SLES9 has 0x2000000 as default.

Re: [PATCH] change compat shmget size arg to signed

[Stephen Rothwell]

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On Fri, 24 Feb 2006 00:27:17 +0100 Olaf Hering <olh@suse.de> wrote:
>
>  On Fri, Feb 24, Stephen Rothwell wrote:
> 
> > Does the ltp test fail on a standard kernel(where SHMMAX is 0x2000000), or
> > only on a SLES kernel (where SHMMAX is ULONG_MAX)?
> 
> It fails with SLES9 and SLES10. SLES9 has 0x2000000 as default.

So what was shm_ctlmax set to when the test was run.

I am trying to figure out why this test:

if (size < SHMMIN || size > shm_ctlmax)
                return -EINVAL;

Doesn't return -EINVAL for size == 0xffffffff if shm_ctlmax is 0x2000000?

-- 
Cheers,
Stephen Rothwell                    sfr@canb.auug.org.au
http://www.canb.auug.org.au/~sfr/

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Re: [PATCH] change compat shmget size arg to signed

[Olaf Hering]

 On Fri, Feb 24, Stephen Rothwell wrote:

> On Fri, 24 Feb 2006 00:27:17 +0100 Olaf Hering <olh@suse.de> wrote:
> >
> >  On Fri, Feb 24, Stephen Rothwell wrote:
> > 
> > > Does the ltp test fail on a standard kernel(where SHMMAX is 0x2000000), or
> > > only on a SLES kernel (where SHMMAX is ULONG_MAX)?
> > 
> > It fails with SLES9 and SLES10. SLES9 has 0x2000000 as default.
> 
> So what was shm_ctlmax set to when the test was run.
> 
> I am trying to figure out why this test:
> 
> if (size < SHMMIN || size > shm_ctlmax)
>                 return -EINVAL;
> 
> Doesn't return -EINVAL for size == 0xffffffff if shm_ctlmax is 0x2000000?

shm_ctlmax is a sysctrl, so it can have anything. The ltp test is
invalid. shmget02 dos not fail after:
echo $(( 0x2000000 )) > /proc/sys/kernel/shmmax