by Ben Hutchings

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Subject: Re: [ 12/48] signal: always clear sa_restorer on execve

On Wed, 2013-03-20 at 21:43 +0100, Sebastian Gottschall (DD-WRT) wrote:
> Am 20.03.2013 20:02, schrieb Sebastian Gottschall (DD-WRT):
> > Hello
> >
> > The patch for sa_restorer will break mips builds, since sa_restorer
> > isnt defined as field within the struct, but the MACRO is.
> > so use the __ARCH_HAS_SA_RESTORER way which is implemented in that way
> > in linux 3.9 or simply revert the patch

This also appears to break blackfin, ia64, parisc and tile.

I think for earlier 3.x.y series we can use one of the attached
(untested) patches to define __ARCH_HAS_SA_RESTORER appropriately, and
then apply the upstream change:

commit 522cff142d7d2f9230839c9e1f21a4d8bcc22a4a
Author: Andrew Morton <[email protected]>
Date: Wed Mar 13 14:59:34 2013 -0700

kernel/signal.c: use __ARCH_HAS_SA_RESTORER instead of SA_RESTORER

Ben.

--
Ben Hutchings
It is easier to write an incorrect program than to understand a correct one.

Attachments:

signal-fix-use-of-missing-sa_restorer-field-3.0-3.2-3.4.patch (4.33 kB)
signal-fix-use-of-missing-sa_restorer-field-3.8.patch (4.28 kB)
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2013-03-26 04:45:55

by Ben Hutchings

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Subject: signal: Define __ARCH_HAS_SA_RESTORER so we know whether to clear sa_restorer

On Thu, 2013-03-21 at 01:41 +0000, Ben Hutchings wrote:
> On Wed, 2013-03-20 at 21:43 +0100, Sebastian Gottschall (DD-WRT) wrote:
> > Am 20.03.2013 20:02, schrieb Sebastian Gottschall (DD-WRT):
> > > Hello
> > >
> > > The patch for sa_restorer will break mips builds, since sa_restorer
> > > isnt defined as field within the struct, but the MACRO is.
> > > so use the __ARCH_HAS_SA_RESTORER way which is implemented in that way
> > > in linux 3.9 or simply revert the patch
>
> This also appears to break blackfin, ia64, parisc and tile.
>
> I think for earlier 3.x.y series we can use one of the attached
> (untested) patches to define __ARCH_HAS_SA_RESTORER appropriately, and
> then apply the upstream change:
>
> commit 522cff142d7d2f9230839c9e1f21a4d8bcc22a4a
> Author: Andrew Morton <[email protected]>
> Date: Wed Mar 13 14:59:34 2013 -0700
>
> kernel/signal.c: use __ARCH_HAS_SA_RESTORER instead of SA_RESTORER
>
> Ben.

The Debian package of 3.2.41, which included these two patches, built on
mips and ia64. (Actually it failed on ia64, but *compilation* was
successful.)

(This does not, of course, prove that I didn't un-fix the information
leak.)

Here is the first patch again (separate versions for 3.8.y and for
earlier series), now with a more accurate subject line. I'm going to
include this in 3.2.42.

Ben.

--
Ben Hutchings
The two most common things in the universe are hydrogen and stupidity.

Attachments:

signal-define-__arch_has_sa_restorer-so-we-know-whether-to-clear-3.0-3.2-3.4.patch (4.36 kB)
signal-define-__arch_has_sa_restorer-so-we-know-whether-to-clear-3.8.patch (4.31 kB)
signature.asc (828.00 B)
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2013-03-26 14:04:43

by Luis Henriques

[permalink] [raw]

Subject: Re: signal: Define __ARCH_HAS_SA_RESTORER so we know whether to clear sa_restorer

On Tue, Mar 26, 2013 at 04:45:42AM +0000, Ben Hutchings wrote:
> On Thu, 2013-03-21 at 01:41 +0000, Ben Hutchings wrote:
> > On Wed, 2013-03-20 at 21:43 +0100, Sebastian Gottschall (DD-WRT) wrote:
> > > Am 20.03.2013 20:02, schrieb Sebastian Gottschall (DD-WRT):
> > > > Hello
> > > >
> > > > The patch for sa_restorer will break mips builds, since sa_restorer
> > > > isnt defined as field within the struct, but the MACRO is.
> > > > so use the __ARCH_HAS_SA_RESTORER way which is implemented in that way
> > > > in linux 3.9 or simply revert the patch
> >
> > This also appears to break blackfin, ia64, parisc and tile.
> >
> > I think for earlier 3.x.y series we can use one of the attached
> > (untested) patches to define __ARCH_HAS_SA_RESTORER appropriately, and
> > then apply the upstream change:
> >
> > commit 522cff142d7d2f9230839c9e1f21a4d8bcc22a4a
> > Author: Andrew Morton <[email protected]>
> > Date: Wed Mar 13 14:59:34 2013 -0700
> >
> > kernel/signal.c: use __ARCH_HAS_SA_RESTORER instead of SA_RESTORER
> >
> > Ben.
>
> The Debian package of 3.2.41, which included these two patches, built on
> mips and ia64. (Actually it failed on ia64, but *compilation* was
> successful.)
>
> (This does not, of course, prove that I didn't un-fix the information
> leak.)
>
> Here is the first patch again (separate versions for 3.8.y and for
> earlier series), now with a more accurate subject line. I'm going to
> include this in 3.2.42.

Thanks a lot Ben. I'm queuing it for 3.5.

Cheers,
--
Luis

>
> Ben.
>
> --
> Ben Hutchings
> The two most common things in the universe are hydrogen and stupidity.
>

> From: Ben Hutchings <[email protected]>
> Date: Sun, 25 Nov 2012 22:24:19 -0500
> Subject: signal: Define __ARCH_HAS_SA_RESTORER so we know whether to clear sa_restorer
>
> flush_signal_handlers() needs to know whether sigaction::sa_restorer
> is defined, not whether SA_RESTORER is defined. Define the
> __ARCH_HAS_SA_RESTORER macro to indicate this.
>
> Vaguely based on upstream commit 574c4866e33d 'consolidate kernel-side
> struct sigaction declarations'.
>
> Signed-off-by: Ben Hutchings <[email protected]>
> Cc: Al Viro <[email protected]>
> ---
> --- a/arch/arm/include/asm/signal.h
> +++ b/arch/arm/include/asm/signal.h
> @@ -127,6 +127,7 @@ struct sigaction {
> __sigrestore_t sa_restorer;
> sigset_t sa_mask; /* mask last for extensibility */
> };
> +#define __ARCH_HAS_SA_RESTORER
>
> struct k_sigaction {
> struct sigaction sa;
> --- a/arch/avr32/include/asm/signal.h
> +++ b/arch/avr32/include/asm/signal.h
> @@ -128,6 +128,7 @@ struct sigaction {
> __sigrestore_t sa_restorer;
> sigset_t sa_mask; /* mask last for extensibility */
> };
> +#define __ARCH_HAS_SA_RESTORER
>
> struct k_sigaction {
> struct sigaction sa;
> --- a/arch/cris/include/asm/signal.h
> +++ b/arch/cris/include/asm/signal.h
> @@ -122,6 +122,7 @@ struct sigaction {
> void (*sa_restorer)(void);
> sigset_t sa_mask; /* mask last for extensibility */
> };
> +#define __ARCH_HAS_SA_RESTORER
>
> struct k_sigaction {
> struct sigaction sa;
> --- a/arch/h8300/include/asm/signal.h
> +++ b/arch/h8300/include/asm/signal.h
> @@ -121,6 +121,7 @@ struct sigaction {
> void (*sa_restorer)(void);
> sigset_t sa_mask; /* mask last for extensibility */
> };
> +#define __ARCH_HAS_SA_RESTORER
>
> struct k_sigaction {
> struct sigaction sa;
> --- a/arch/m32r/include/asm/signal.h
> +++ b/arch/m32r/include/asm/signal.h
> @@ -123,6 +123,7 @@ struct sigaction {
> __sigrestore_t sa_restorer;
> sigset_t sa_mask; /* mask last for extensibility */
> };
> +#define __ARCH_HAS_SA_RESTORER
>
> struct k_sigaction {
> struct sigaction sa;
> --- a/arch/m68k/include/asm/signal.h
> +++ b/arch/m68k/include/asm/signal.h
> @@ -119,6 +119,7 @@ struct sigaction {
> __sigrestore_t sa_restorer;
> sigset_t sa_mask; /* mask last for extensibility */
> };
> +#define __ARCH_HAS_SA_RESTORER
>
> struct k_sigaction {
> struct sigaction sa;
> --- a/arch/mn10300/include/asm/signal.h
> +++ b/arch/mn10300/include/asm/signal.h
> @@ -131,6 +131,7 @@ struct sigaction {
> __sigrestore_t sa_restorer;
> sigset_t sa_mask; /* mask last for extensibility */
> };
> +#define __ARCH_HAS_SA_RESTORER
>
> struct k_sigaction {
> struct sigaction sa;
> --- a/arch/powerpc/include/asm/signal.h
> +++ b/arch/powerpc/include/asm/signal.h
> @@ -109,6 +109,7 @@ struct sigaction {
> __sigrestore_t sa_restorer;
> sigset_t sa_mask; /* mask last for extensibility */
> };
> +#define __ARCH_HAS_SA_RESTORER
>
> struct k_sigaction {
> struct sigaction sa;
> --- a/arch/s390/include/asm/signal.h
> +++ b/arch/s390/include/asm/signal.h
> @@ -131,6 +131,7 @@ struct sigaction {
> void (*sa_restorer)(void);
> sigset_t sa_mask; /* mask last for extensibility */
> };
> +#define __ARCH_HAS_SA_RESTORER
>
> struct k_sigaction {
> struct sigaction sa;
> --- a/arch/sparc/include/asm/signal.h
> +++ b/arch/sparc/include/asm/signal.h
> @@ -191,6 +191,7 @@ struct __old_sigaction {
> unsigned long sa_flags;
> void (*sa_restorer)(void); /* not used by Linux/SPARC yet */
> };
> +#define __ARCH_HAS_SA_RESTORER
>
> typedef struct sigaltstack {
> void __user *ss_sp;
> --- a/arch/x86/include/asm/signal.h
> +++ b/arch/x86/include/asm/signal.h
> @@ -125,6 +125,8 @@ typedef unsigned long sigset_t;
> extern void do_notify_resume(struct pt_regs *, void *, __u32);
> # endif /* __KERNEL__ */
>
> +#define __ARCH_HAS_SA_RESTORER
> +
> #ifdef __i386__
> # ifdef __KERNEL__
> struct old_sigaction {
> --- a/arch/xtensa/include/asm/signal.h
> +++ b/arch/xtensa/include/asm/signal.h
> @@ -133,6 +133,7 @@ struct sigaction {
> void (*sa_restorer)(void);
> sigset_t sa_mask; /* mask last for extensibility */
> };
> +#define __ARCH_HAS_SA_RESTORER
>
> struct k_sigaction {
> struct sigaction sa;
> --- a/include/asm-generic/signal.h
> +++ b/include/asm-generic/signal.h
> @@ -99,6 +99,10 @@ typedef unsigned long old_sigset_t;
>
> #include <asm-generic/signal-defs.h>
>
> +#ifdef SA_RESTORER
> +#define __ARCH_HAS_SA_RESTORER
> +#endif
> +
> struct sigaction {
> __sighandler_t sa_handler;
> unsigned long sa_flags;

> From: Ben Hutchings <[email protected]>
> Date: Sun, 25 Nov 2012 22:24:19 -0500
> Subject: signal: Define __ARCH_HAS_SA_RESTORER so we know whether to clear sa_restorer
>
> flush_signal_handlers() needs to know whether sigaction::sa_restorer
> is defined, not whether SA_RESTORER is defined. Define the
> __ARCH_HAS_SA_RESTORER macro to indicate this.
>
> Vaguely based on upstream commit 574c4866e33d 'consolidate kernel-side
> struct sigaction declarations'.
>
> Signed-off-by: Ben Hutchings <[email protected]>
> Cc: Al Viro <[email protected]>
> ---
> --- a/arch/arm/include/asm/signal.h
> +++ b/arch/arm/include/asm/signal.h
> @@ -29,6 +29,7 @@ struct sigaction {
> __sigrestore_t sa_restorer;
> sigset_t sa_mask; /* mask last for extensibility */
> };
> +#define __ARCH_HAS_SA_RESTORER
>
> struct k_sigaction {
> struct sigaction sa;
> --- a/arch/avr32/include/asm/signal.h
> +++ b/arch/avr32/include/asm/signal.h
> @@ -29,6 +29,7 @@ struct sigaction {
> __sigrestore_t sa_restorer;
> sigset_t sa_mask; /* mask last for extensibility */
> };
> +#define __ARCH_HAS_SA_RESTORER
>
> struct k_sigaction {
> struct sigaction sa;
> --- a/arch/cris/include/asm/signal.h
> +++ b/arch/cris/include/asm/signal.h
> @@ -29,6 +29,7 @@ struct sigaction {
> void (*sa_restorer)(void);
> sigset_t sa_mask; /* mask last for extensibility */
> };
> +#define __ARCH_HAS_SA_RESTORER
>
> struct k_sigaction {
> struct sigaction sa;
> --- a/arch/h8300/include/asm/signal.h
> +++ b/arch/h8300/include/asm/signal.h
> @@ -29,6 +29,7 @@ struct sigaction {
> void (*sa_restorer)(void);
> sigset_t sa_mask; /* mask last for extensibility */
> };
> +#define __ARCH_HAS_SA_RESTORER
>
> struct k_sigaction {
> struct sigaction sa;
> --- a/arch/m32r/include/asm/signal.h
> +++ b/arch/m32r/include/asm/signal.h
> @@ -22,6 +22,7 @@ struct sigaction {
> __sigrestore_t sa_restorer;
> sigset_t sa_mask; /* mask last for extensibility */
> };
> +#define __ARCH_HAS_SA_RESTORER
>
> struct k_sigaction {
> struct sigaction sa;
> --- a/arch/m68k/include/asm/signal.h
> +++ b/arch/m68k/include/asm/signal.h
> @@ -29,6 +29,7 @@ struct sigaction {
> __sigrestore_t sa_restorer;
> sigset_t sa_mask; /* mask last for extensibility */
> };
> +#define __ARCH_HAS_SA_RESTORER
>
> struct k_sigaction {
> struct sigaction sa;
> --- a/arch/mn10300/include/asm/signal.h
> +++ b/arch/mn10300/include/asm/signal.h
> @@ -39,6 +39,7 @@ struct sigaction {
> __sigrestore_t sa_restorer;
> sigset_t sa_mask; /* mask last for extensibility */
> };
> +#define __ARCH_HAS_SA_RESTORER
>
> struct k_sigaction {
> struct sigaction sa;
> --- a/arch/powerpc/include/asm/signal.h
> +++ b/arch/powerpc/include/asm/signal.h
> @@ -1,6 +1,7 @@
> #ifndef _ASM_POWERPC_SIGNAL_H
> #define _ASM_POWERPC_SIGNAL_H
>
> +#define __ARCH_HAS_SA_RESTORER
> #include <uapi/asm/signal.h>
>
> #endif /* _ASM_POWERPC_SIGNAL_H */
> --- a/arch/s390/include/asm/signal.h
> +++ b/arch/s390/include/asm/signal.h
> @@ -34,6 +34,7 @@ struct sigaction {
> void (*sa_restorer)(void);
> sigset_t sa_mask; /* mask last for extensibility */
> };
> +#define __ARCH_HAS_SA_RESTORER
>
> struct k_sigaction {
> struct sigaction sa;
> --- a/arch/sparc/include/asm/signal.h
> +++ b/arch/sparc/include/asm/signal.h
> @@ -26,5 +26,7 @@ struct k_sigaction {
> void __user *ka_restorer;
> };
>
> +#define __ARCH_HAS_SA_RESTORER
> +
> #endif /* !(__ASSEMBLY__) */
> #endif /* !(__SPARC_SIGNAL_H) */
> --- a/arch/x86/include/asm/signal.h
> +++ b/arch/x86/include/asm/signal.h
> @@ -31,6 +31,9 @@ typedef sigset_t compat_sigset_t;
> #include <uapi/asm/signal.h>
> #ifndef __ASSEMBLY__
> extern void do_notify_resume(struct pt_regs *, void *, __u32);
> +
> +#define __ARCH_HAS_SA_RESTORER
> +
> #ifdef __i386__
> struct old_sigaction {
> __sighandler_t sa_handler;
> --- a/arch/xtensa/include/asm/signal.h
> +++ b/arch/xtensa/include/asm/signal.h
> @@ -21,6 +21,7 @@ struct sigaction {
> void (*sa_restorer)(void);
> sigset_t sa_mask; /* mask last for extensibility */
> };
> +#define __ARCH_HAS_SA_RESTORER
>
> struct k_sigaction {
> struct sigaction sa;
> --- a/include/uapi/asm-generic/signal.h
> +++ b/include/uapi/asm-generic/signal.h
> @@ -93,6 +93,10 @@ typedef unsigned long old_sigset_t;
>
> #include <asm-generic/signal-defs.h>
>
> +#ifdef SA_RESTORER
> +#define __ARCH_HAS_SA_RESTORER
> +#endif
> +
> struct sigaction {
> __sighandler_t sa_handler;
> unsigned long sa_flags;