hppa: Fix setting of __libc_stack_end
Commit Message
The binutils package was recently changed to fix -z relro support on hppa. See ld/21000 for details:
https://sourceware.org/bugzilla/show_bug.cgi?id=21000
This exposed a problem with the _dl_start_user function in the RTLD_START define. We need to
set __libc_stack_end before it is made read only. For this, we need to define DL_STACK_END.
The offset of 0x160 gives the same stack end as the code in _dl_start_user.
A build log with the attached patch is here:
https://buildd.debian.org/status/fetch.php?pkg=glibc&arch=hppa&ver=2.24-9&stamp=1487639205&raw=0
I don't have write permission, so somebody should commit this for me. Thanks.
Dave
--
John David Anglin dave.anglin@bell.net
2017-02-20 John David Anglin <danglin@gcc.gnu.org>
* sysdeps/hppa/dl-machine.h (DL_STACK_END): Define.
(RTLD_START): Don't record stack end address in _dl_start_user.
Comments
On 20 Feb 2017 20:31, John David Anglin wrote:
> The binutils package was recently changed to fix -z relro support on hppa. See ld/21000 for details:
> https://sourceware.org/bugzilla/show_bug.cgi?id=21000
>
> This exposed a problem with the _dl_start_user function in the RTLD_START define. We need to
> set __libc_stack_end before it is made read only. For this, we need to define DL_STACK_END.
> The offset of 0x160 gives the same stack end as the code in _dl_start_user.
>
> A build log with the attached patch is here:
> https://buildd.debian.org/status/fetch.php?pkg=glibc&arch=hppa&ver=2.24-9&stamp=1487639205&raw=0
>
> I don't have write permission, so somebody should commit this for me. Thanks.
pushed now. should i cherry pick back to 2.25 too ?
-mike
On 2017-03-15 4:44 PM, Mike Frysinger wrote:
> pushed now. should i cherry pick back to 2.25 too ?
Thanks Mike. That would be good. Debian is currently at 2.24-9 and
this change
needs to be added for next build/rebuild else build will fail.
Dave
@@ -302,6 +302,10 @@ elf_machine_runtime_setup (struct link_map *l, int lazy, int profile)
#define ARCH_LA_PLTENTER hppa_gnu_pltenter
#define ARCH_LA_PLTEXIT hppa_gnu_pltexit
+/* Adjust DL_STACK_END to get value we want in __libc_stack_end. */
+#define DL_STACK_END(cookie) \
+ ((void *) (((long) (cookie)) + 0x160))
+
/* Initial entry point code for the dynamic linker.
The C function `_dl_start' is the real entry point;
its return value is the user program's entry point. */
@@ -401,11 +405,6 @@ asm ( \
/* Save the entry point in %r3. */ \
" copy %ret0,%r3\n" \
\
- /* Remember the lowest stack address. */ \
-" addil LT'__libc_stack_end,%r19\n" \
-" ldw RT'__libc_stack_end(%r1),%r20\n" \
-" stw %sp,0(%r20)\n" \
- \
/* See if we were called as a command with the executable file \
name as an extra leading argument. */ \
" addil LT'_dl_skip_args,%r19\n" \