LinuxLists.cc - [PATCH v5 13/25] m68k: add asm/syscall.h

2018-12-10 04:32:36

Subject: [PATCH v5 13/25] m68k: add asm/syscall.h

syscall_get_* functions are required to be implemented on all
architectures in order to extend the generic ptrace API with
PTRACE_GET_SYSCALL_INFO request.

This introduces asm/syscall.h on m68k implementing all 5 syscall_get_*
functions as documented in asm-generic/syscall.h: syscall_get_nr,
syscall_get_arguments, syscall_get_error, syscall_get_return_value,
and syscall_get_arch.

Cc: Geert Uytterhoeven <[email protected]>
Cc: Oleg Nesterov <[email protected]>
Cc: Andy Lutomirski <[email protected]>
Cc: Elvira Khabirova <[email protected]>
Cc: Eugene Syromyatnikov <[email protected]>
Cc: [email protected]
Signed-off-by: Dmitry V. Levin <[email protected]>
---

Notes:
v5: added syscall_get_nr, syscall_get_arguments, syscall_get_error,
and syscall_get_return_value
v1: added syscall_get_arch

arch/m68k/include/asm/syscall.h | 39 +++++++++++++++++++++++++++++++++
1 file changed, 39 insertions(+)
create mode 100644 arch/m68k/include/asm/syscall.h

diff --git a/arch/m68k/include/asm/syscall.h b/arch/m68k/include/asm/syscall.h
new file mode 100644
index 000000000000..75a24cf90620
--- /dev/null
+++ b/arch/m68k/include/asm/syscall.h
@@ -0,0 +1,39 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _ASM_M68K_SYSCALL_H
+#define _ASM_M68K_SYSCALL_H
+
+#include <uapi/linux/audit.h>
+
+static inline int
+syscall_get_nr(struct task_struct *task, struct pt_regs *regs)
+{
+ return regs->orig_d0;
+}
+
+static inline void
+syscall_get_arguments(struct task_struct *task, struct pt_regs *regs,
+ unsigned int i, unsigned int n, unsigned long *args)
+{
+ BUG_ON(i + n > 6);
+ memcpy(args, &regs->d1 + i, n * sizeof(args[0]));
+}
+
+static inline long
+syscall_get_error(struct task_struct *task, struct pt_regs *regs)
+{
+ return IS_ERR_VALUE(regs->d0) ? regs->d0 : 0;
+}
+
+static inline long
+syscall_get_return_value(struct task_struct *task, struct pt_regs *regs)
+{
+ return regs->d0;
+}
+
+static inline int
+syscall_get_arch(void)
+{
+ return AUDIT_ARCH_M68K;
+}
+
+#endif /* _ASM_M68K_SYSCALL_H */
--
ldv

2018-12-10 09:18:32

by Geert Uytterhoeven

[permalink] [raw]

Subject: Re: [PATCH v5 13/25] m68k: add asm/syscall.h

Hi Dmitry,

On Mon, Dec 10, 2018 at 5:30 AM Dmitry V. Levin <[email protected]> wrote:
> syscall_get_* functions are required to be implemented on all
> architectures in order to extend the generic ptrace API with
> PTRACE_GET_SYSCALL_INFO request.
>
> This introduces asm/syscall.h on m68k implementing all 5 syscall_get_*
> functions as documented in asm-generic/syscall.h: syscall_get_nr,
> syscall_get_arguments, syscall_get_error, syscall_get_return_value,
> and syscall_get_arch.
>
> Cc: Geert Uytterhoeven <[email protected]>
> Cc: Oleg Nesterov <[email protected]>
> Cc: Andy Lutomirski <[email protected]>
> Cc: Elvira Khabirova <[email protected]>
> Cc: Eugene Syromyatnikov <[email protected]>
> Cc: [email protected]
> Signed-off-by: Dmitry V. Levin <[email protected]>
> ---
>
> Notes:
> v5: added syscall_get_nr, syscall_get_arguments, syscall_get_error,
> and syscall_get_return_value
> v1: added syscall_get_arch

> --- /dev/null
> +++ b/arch/m68k/include/asm/syscall.h
> @@ -0,0 +1,39 @@

> +static inline void
> +syscall_get_arguments(struct task_struct *task, struct pt_regs *regs,
> + unsigned int i, unsigned int n, unsigned long *args)
> +{
> + BUG_ON(i + n > 6);

Does this have to crash the kernel?
Perhaps you can return an error code instead?

> + memcpy(args, &regs->d1 + i, n * sizeof(args[0]));
> +}

Gr{oetje,eeting}s,

Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- [email protected]

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds

2018-12-10 12:55:24

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2018-12-12 23:13:41

by Dmitry V. Levin

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Subject: Re: [PATCH v5 13/25] m68k: add asm/syscall.h

Hi Geert,

On Wed, Dec 12, 2018 at 04:07:11PM +0300, Dmitry V. Levin wrote:
> On Wed, Dec 12, 2018 at 01:54:05PM +0100, Geert Uytterhoeven wrote:
> > On Wed, Dec 12, 2018 at 1:37 PM Dmitry V. Levin <[email protected]> wrote:
> > > On Wed, Dec 12, 2018 at 01:27:14PM +0100, Geert Uytterhoeven wrote:
> > > > On Wed, Dec 12, 2018 at 1:04 PM Dmitry V. Levin <[email protected]> wrote:
> > > > > On Wed, Dec 12, 2018 at 10:43:33AM +0100, Geert Uytterhoeven wrote:
> > > > > > On Wed, Dec 12, 2018 at 10:27 AM Dmitry V. Levin <[email protected]> wrote:
> > > > > > > On Wed, Dec 12, 2018 at 10:01:29AM +0100, Geert Uytterhoeven wrote:
> > > > > > > > On Wed, Dec 12, 2018 at 9:55 AM Dmitry V. Levin <[email protected]> wrote:
> > > > > > > > > On Mon, Dec 10, 2018 at 04:30:25PM +0300, Dmitry V. Levin wrote:
> > > > > > > > > > On Mon, Dec 10, 2018 at 02:06:28PM +0100, Geert Uytterhoeven wrote:
> > > > > > > > > > > On Mon, Dec 10, 2018 at 1:41 PM Dmitry V. Levin <[email protected]> wrote:
> > > > > > > > > > > > On Mon, Dec 10, 2018 at 09:45:42AM +0100, Geert Uytterhoeven wrote:
> > > > > > > > > > > > > On Mon, Dec 10, 2018 at 5:30 AM Dmitry V. Levin <[email protected]> wrote:
> > > > > > > > > > > > > > syscall_get_* functions are required to be implemented on all
> > > > > > > > > > > > > > architectures in order to extend the generic ptrace API with
> > > > > > > > > > > > > > PTRACE_GET_SYSCALL_INFO request.
> > > > > > > > > > > > > >
> > > > > > > > > > > > > > This introduces asm/syscall.h on m68k implementing all 5 syscall_get_*
> > > > > > > > > > > > > > functions as documented in asm-generic/syscall.h: syscall_get_nr,
> > > > > > > > > > > > > > syscall_get_arguments, syscall_get_error, syscall_get_return_value,
> > > > > > > > > > > > > > and syscall_get_arch.
> > > > > > > > > > > > > >
> > > > > > > > > > > > > > Cc: Geert Uytterhoeven <[email protected]>
> > > > > > > > > > > > > > Cc: Oleg Nesterov <[email protected]>
> > > > > > > > > > > > > > Cc: Andy Lutomirski <[email protected]>
> > > > > > > > > > > > > > Cc: Elvira Khabirova <[email protected]>
> > > > > > > > > > > > > > Cc: Eugene Syromyatnikov <[email protected]>
> > > > > > > > > > > > > > Cc: [email protected]
> > > > > > > > > > > > > > Signed-off-by: Dmitry V. Levin <[email protected]>
> > > > > > > > > > > > > > ---
> > > > > > > > > > > > > >
> > > > > > > > > > > > > > Notes:
> > > > > > > > > > > > > > v5: added syscall_get_nr, syscall_get_arguments, syscall_get_error,
> > > > > > > > > > > > > > and syscall_get_return_value
> > > > > > > > > > > > > > v1: added syscall_get_arch
> > > > > > > > > > > > >
> > > > > > > > > > > > > > --- /dev/null
> > > > > > > > > > > > > > +++ b/arch/m68k/include/asm/syscall.h
> > > > > > > > > > > > > > @@ -0,0 +1,39 @@
> > > > > > > > > > > > >
> > > > > > > > > > > > > > +static inline void
> > > > > > > > > > > > > > +syscall_get_arguments(struct task_struct *task, struct pt_regs *regs,
> > > > > > > > > > > > > > + unsigned int i, unsigned int n, unsigned long *args)
> > > > > > > > > > > > > > +{
> > > > > > > > > > > > > > + BUG_ON(i + n > 6);
> > > > > > > > > > > > >
> > > > > > > > > > > > > Does this have to crash the kernel?
> > > > > > > > > > > >
> > > > > > > > > > > > This is what most of other architectures do, but we could choose
> > > > > > > > > > > > a softer approach, e.g. use WARN_ON_ONCE instead.
> > > > > > > > > > > >
> > > > > > > > > > > > > Perhaps you can return an error code instead?
> > > > > > > > > > > >
> > > > > > > > > > > > That would be problematic given the signature of this function
> > > > > > > > > > > > and the nature of the potential bug which would most likely be a usage error.
> > > > > > > > > > >
> > > > > > > > > > > Of course to handle that, the function's signature need to be changed.
> > > > > > > > > > > Changing it has the advantage that the error handling can be done at the
> > > > > > > > > > > caller, in common code, instead of duplicating it for all
> > > > > > > > > > > architectures, possibly
> > > > > > > > > > > leading to different semantics.
> > > > > > > > > >
> > > > > > > > > > Given that *all* current users of syscall_get_arguments specify i == 0
> > > > > > > > > > (and there is an architecture that has BUG_ON(i)),
> > > > > > > > > > it should be really a usage error to get into situation where i + n > 6,
> > > > > > > > > > I wish a BUILD_BUG_ON could be used here instead.
> > > > > > > > > >
> > > > > > > > > > I don't think it worths pushing the change of API just to convert
> > > > > > > > > > a "cannot happen" assertion into an error that would have to be dealt with
> > > > > > > > > > on the caller side.
> > > > > > > > >
> > > > > > > > > I suggest the following BUG_ON replacement for syscall_get_arguments:
> > > > > > > > >
> > > > > > > > > #define SYSCALL_MAX_ARGS 6
> > > > > > > > >
> > > > > > > > > static inline void
> > > > > > > > > syscall_get_arguments(struct task_struct *task, struct pt_regs *regs,
> > > > > > > > > unsigned int i, unsigned int n, unsigned long *args)
> > > > > > > > > {
> > > > > > > > > /*
> > > > > > > > > * Ideally there should have been
> > > > > > > > > * BUILD_BUG_ON(i + n > SYSCALL_MAX_ARGS);
> > > > > > > > > * instead of these checks.
> > > > > > > > > */
> > > > > > > > > if (unlikely(i > SYSCALL_MAX_ARGS)) {
> > > > > > > > > WARN_ONCE(1, "i > SYSCALL_MAX_ARGS");
> > > > > > > > > return;
> > > > > > > >
> > > > > > > > Does this have security implications, as args is an output parameter?
> > > > > > > > I.e. if you don't fill the array, the caller will use whatever is on the stack.
> > > > > > > > Can this ever be passed to userspace, leaking data?
> > > > > > >
> > > > > > > In the current kernel code n is always less or equal to 6,
> > > > > > > but in theory future changes can potentially break the assertion
> > > > > > > and this could lead to leaking data to userspace.
> > > > > >
> > > > > > OK.
> > > > > >
> > > > > > > Do you think we should rather be defensive and add some memsets, e.g.
> > > > > > >
> > > > > > > if (unlikely(i > SYSCALL_MAX_ARGS)) {
> > > > > > > WARN_ONCE(1, "i > SYSCALL_MAX_ARGS");
> > > > > > > memset(args, 0, n * sizeof(args[0]));
> > > > > > > return;
> > > > > > > }
> > > > > > > if (unlikely(n > SYSCALL_MAX_ARGS - i)) {
> > > > > > > unsigned int extra = n - (SYSCALL_MAX_ARGS - i);
> > > > > > >
> > > > > > > WARN_ONCE(1, "i + n > SYSCALL_MAX_ARGS");
> > > > > > > n = SYSCALL_MAX_ARGS - i;
> > > > > > > memset(&args[n], 0, extra * sizeof(args[0]));
> > > > > > > }
> > > > > > > ?
> > > > > >
> > > > > > Yes please.
> > > > > >
> > > > > > But please handle all of that in the generic code, so it doesn't have to be
> > > > > > replicated across all architectures.
> > > > > >
> > > > > > E.g. make syscall_get_arguments() a wrapper in generic code, calling
> > > > > > __syscall_get_arguments() in architecture-specific code.
> > > > > >
> > > > > > And make the latter return int, so it can indicate other failures.
> > > > >
> > > > > Other failures? What syscall_get_arguments is expected to do
> > > > > if __syscall_get_arguments returned, say, -1?
> > > >
> > > > Fail. Just like in case of other generic ill conditions it can detect itself.
> > >
> > > Sorry, I don't quite follow. syscall_get_arguments() has no return code,
> >
> > Which may be an indicator for a different problem.
> > What is e.g. populate_seccomp_data() supposed to do if
> > syscall_get_arguments() fails?
>
> Well, syscall_get_arguments() is not supposed to fail if invoked properly.
>
> Currently populate_seccomp_data() does this:
> struct task_struct *task = current;
> struct pt_regs *regs = task_pt_regs(task);
> unsigned long args[6];
> ...
> syscall_get_arguments(task, regs, 0, 6, args);
>
> I don't see how this could fail.
>
> > > so all it can possibly do is to zero out args[], e.g.
> > >
> > > if (unlikely(__syscall_get_arguments(task, regs, i, n, args) < 0)) {
> > > memset(args, 0, n * sizeof(args[0]));
> > > return;
> > > }
> > >
> > > Do you mean this?
> >
> > Exactly.
>
> OK, I'll prepare the change, thanks.

I have the change ready, but I don't like it. The only architecture
that could benefit from being able of signalling an error condition to
syscall_get_arguments is MIPS, and even in that case the return code is
not suitable because it wouldn't help to distinguish between the first 4
syscall arguments that cannot cause an error and remaining arguments that
can. It looks like there is no need to make __syscall_get_arguments()
to return int after all.

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2019-03-29 22:05:53

by Dmitry V. Levin

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Subject: Re: [PATCH v5 13/25] m68k: add asm/syscall.h

On Wed, Dec 12, 2018 at 11:55:16AM +0300, Dmitry V. Levin wrote:
> On Mon, Dec 10, 2018 at 04:30:25PM +0300, Dmitry V. Levin wrote:
> > On Mon, Dec 10, 2018 at 02:06:28PM +0100, Geert Uytterhoeven wrote:
> > > On Mon, Dec 10, 2018 at 1:41 PM Dmitry V. Levin <[email protected]> wrote:
> > > > On Mon, Dec 10, 2018 at 09:45:42AM +0100, Geert Uytterhoeven wrote:
> > > > > On Mon, Dec 10, 2018 at 5:30 AM Dmitry V. Levin <[email protected]> wrote:
> > > > > > syscall_get_* functions are required to be implemented on all
> > > > > > architectures in order to extend the generic ptrace API with
> > > > > > PTRACE_GET_SYSCALL_INFO request.
> > > > > >
> > > > > > This introduces asm/syscall.h on m68k implementing all 5 syscall_get_*
> > > > > > functions as documented in asm-generic/syscall.h: syscall_get_nr,
> > > > > > syscall_get_arguments, syscall_get_error, syscall_get_return_value,
> > > > > > and syscall_get_arch.
> > > > > >
> > > > > > Cc: Geert Uytterhoeven <[email protected]>
> > > > > > Cc: Oleg Nesterov <[email protected]>
> > > > > > Cc: Andy Lutomirski <[email protected]>
> > > > > > Cc: Elvira Khabirova <[email protected]>
> > > > > > Cc: Eugene Syromyatnikov <[email protected]>
> > > > > > Cc: [email protected]
> > > > > > Signed-off-by: Dmitry V. Levin <[email protected]>
> > > > > > ---
> > > > > >
> > > > > > Notes:
> > > > > > v5: added syscall_get_nr, syscall_get_arguments, syscall_get_error,
> > > > > > and syscall_get_return_value
> > > > > > v1: added syscall_get_arch
> > > > >
> > > > > > --- /dev/null
> > > > > > +++ b/arch/m68k/include/asm/syscall.h
> > > > > > @@ -0,0 +1,39 @@
> > > > >
> > > > > > +static inline void
> > > > > > +syscall_get_arguments(struct task_struct *task, struct pt_regs *regs,
> > > > > > + unsigned int i, unsigned int n, unsigned long *args)
> > > > > > +{
> > > > > > + BUG_ON(i + n > 6);
> > > > >
> > > > > Does this have to crash the kernel?
> > > >
> > > > This is what most of other architectures do, but we could choose
> > > > a softer approach, e.g. use WARN_ON_ONCE instead.
> > > >
> > > > > Perhaps you can return an error code instead?
> > > >
> > > > That would be problematic given the signature of this function
> > > > and the nature of the potential bug which would most likely be a usage error.
> > >
> > > Of course to handle that, the function's signature need to be changed.
> > > Changing it has the advantage that the error handling can be done at the
> > > caller, in common code, instead of duplicating it for all
> > > architectures, possibly
> > > leading to different semantics.
> >
> > Given that *all* current users of syscall_get_arguments specify i == 0
> > (and there is an architecture that has BUG_ON(i)),
> > it should be really a usage error to get into situation where i + n > 6,
> > I wish a BUILD_BUG_ON could be used here instead.
> >
> > I don't think it worths pushing the change of API just to convert
> > a "cannot happen" assertion into an error that would have to be dealt with
> > on the caller side.
>
> I suggest the following BUG_ON replacement for syscall_get_arguments:
>
> #define SYSCALL_MAX_ARGS 6
>
> static inline void
> syscall_get_arguments(struct task_struct *task, struct pt_regs *regs,
> unsigned int i, unsigned int n, unsigned long *args)
> {
> /*
> * Ideally there should have been
> * BUILD_BUG_ON(i + n > SYSCALL_MAX_ARGS);
> * instead of these checks.
> */
> if (unlikely(i > SYSCALL_MAX_ARGS)) {
> WARN_ONCE(1, "i > SYSCALL_MAX_ARGS");
> return;
> }
> if (unlikely(n > SYSCALL_MAX_ARGS - i)) {
> WARN_ONCE(1, "i + n > SYSCALL_MAX_ARGS");
> n = SYSCALL_MAX_ARGS - i;
> }
> BUILD_BUG_ON(sizeof(regs->d1) != sizeof(args[0]));
> memcpy(args, &regs->d1 + i, n * sizeof(args[0]));
> }

There seems to be a more straightforward approach to this issue.

Assuming there is a general consensus [1] to get rid of "i" and "n"
arguments of syscall_get_arguments(), the implementation could be
simplified to

static inline void
syscall_get_arguments(struct task_struct *task, struct pt_regs *regs,
unsigned long *args)
{
memcpy(args, &regs->d1, 6 * sizeof(args[0]));
}

[1] https://lore.kernel.org/lkml/[email protected]/

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2019-03-30 20:59:23

by Geert Uytterhoeven

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Subject: Re: [PATCH v5 13/25] m68k: add asm/syscall.h

CC Steven

On Fri, Mar 29, 2019 at 11:04 PM Dmitry V. Levin <[email protected]> wrote:
> On Wed, Dec 12, 2018 at 11:55:16AM +0300, Dmitry V. Levin wrote:
> > On Mon, Dec 10, 2018 at 04:30:25PM +0300, Dmitry V. Levin wrote:
> > > On Mon, Dec 10, 2018 at 02:06:28PM +0100, Geert Uytterhoeven wrote:
> > > > On Mon, Dec 10, 2018 at 1:41 PM Dmitry V. Levin <[email protected]> wrote:
> > > > > On Mon, Dec 10, 2018 at 09:45:42AM +0100, Geert Uytterhoeven wrote:
> > > > > > On Mon, Dec 10, 2018 at 5:30 AM Dmitry V. Levin <[email protected]> wrote:
> > > > > > > syscall_get_* functions are required to be implemented on all
> > > > > > > architectures in order to extend the generic ptrace API with
> > > > > > > PTRACE_GET_SYSCALL_INFO request.
> > > > > > >
> > > > > > > This introduces asm/syscall.h on m68k implementing all 5 syscall_get_*
> > > > > > > functions as documented in asm-generic/syscall.h: syscall_get_nr,
> > > > > > > syscall_get_arguments, syscall_get_error, syscall_get_return_value,
> > > > > > > and syscall_get_arch.
> > > > > > >
> > > > > > > Cc: Geert Uytterhoeven <[email protected]>
> > > > > > > Cc: Oleg Nesterov <[email protected]>
> > > > > > > Cc: Andy Lutomirski <[email protected]>
> > > > > > > Cc: Elvira Khabirova <[email protected]>
> > > > > > > Cc: Eugene Syromyatnikov <[email protected]>
> > > > > > > Cc: [email protected]
> > > > > > > Signed-off-by: Dmitry V. Levin <[email protected]>
> > > > > > > ---
> > > > > > >
> > > > > > > Notes:
> > > > > > > v5: added syscall_get_nr, syscall_get_arguments, syscall_get_error,
> > > > > > > and syscall_get_return_value
> > > > > > > v1: added syscall_get_arch
> > > > > >
> > > > > > > --- /dev/null
> > > > > > > +++ b/arch/m68k/include/asm/syscall.h
> > > > > > > @@ -0,0 +1,39 @@
> > > > > >
> > > > > > > +static inline void
> > > > > > > +syscall_get_arguments(struct task_struct *task, struct pt_regs *regs,
> > > > > > > + unsigned int i, unsigned int n, unsigned long *args)
> > > > > > > +{
> > > > > > > + BUG_ON(i + n > 6);
> > > > > >
> > > > > > Does this have to crash the kernel?
> > > > >
> > > > > This is what most of other architectures do, but we could choose
> > > > > a softer approach, e.g. use WARN_ON_ONCE instead.
> > > > >
> > > > > > Perhaps you can return an error code instead?
> > > > >
> > > > > That would be problematic given the signature of this function
> > > > > and the nature of the potential bug which would most likely be a usage error.
> > > >
> > > > Of course to handle that, the function's signature need to be changed.
> > > > Changing it has the advantage that the error handling can be done at the
> > > > caller, in common code, instead of duplicating it for all
> > > > architectures, possibly
> > > > leading to different semantics.
> > >
> > > Given that *all* current users of syscall_get_arguments specify i == 0
> > > (and there is an architecture that has BUG_ON(i)),
> > > it should be really a usage error to get into situation where i + n > 6,
> > > I wish a BUILD_BUG_ON could be used here instead.
> > >
> > > I don't think it worths pushing the change of API just to convert
> > > a "cannot happen" assertion into an error that would have to be dealt with
> > > on the caller side.
> >
> > I suggest the following BUG_ON replacement for syscall_get_arguments:
> >
> > #define SYSCALL_MAX_ARGS 6
> >
> > static inline void
> > syscall_get_arguments(struct task_struct *task, struct pt_regs *regs,
> > unsigned int i, unsigned int n, unsigned long *args)
> > {
> > /*
> > * Ideally there should have been
> > * BUILD_BUG_ON(i + n > SYSCALL_MAX_ARGS);
> > * instead of these checks.
> > */
> > if (unlikely(i > SYSCALL_MAX_ARGS)) {
> > WARN_ONCE(1, "i > SYSCALL_MAX_ARGS");
> > return;
> > }
> > if (unlikely(n > SYSCALL_MAX_ARGS - i)) {
> > WARN_ONCE(1, "i + n > SYSCALL_MAX_ARGS");
> > n = SYSCALL_MAX_ARGS - i;
> > }
> > BUILD_BUG_ON(sizeof(regs->d1) != sizeof(args[0]));
> > memcpy(args, &regs->d1 + i, n * sizeof(args[0]));
> > }
>
> There seems to be a more straightforward approach to this issue.
>
> Assuming there is a general consensus [1] to get rid of "i" and "n"
> arguments of syscall_get_arguments(), the implementation could be
> simplified to
>
> static inline void
> syscall_get_arguments(struct task_struct *task, struct pt_regs *regs,
> unsigned long *args)
> {
> memcpy(args, &regs->d1, 6 * sizeof(args[0]));
> }
>
> [1] https://lore.kernel.org/lkml/[email protected]/

Yeah, no longer a need for all these ugly checks, good.

Gr{oetje,eeting}s,

Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- [email protected]

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds