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| author | Helge Deller <deller@gmx.de> | 2021-12-08 13:06:52 +0300 |
|---|---|---|
| committer | Helge Deller <deller@gmx.de> | 2022-03-11 21:49:30 +0300 |
| commit | df24e1783e6e0eb3dc0e3ba5a8df3bb0cc537408 (patch) | |
| tree | 73050ce6de41a1fd03e20bffa47c82fb598ef816 /arch/parisc/include/asm/elf.h | |
| parent | 14615ecccb8b0022589b7a7841cdfdf96319724b (diff) | |
| download | linux-df24e1783e6e0eb3dc0e3ba5a8df3bb0cc537408.tar.xz | |
parisc: Add vDSO support
Add minimal vDSO support, which provides the signal trampoline helpers,
but none of the userspace syscall helpers like time wrappers.
The big benefit of this vDSO implementation is, that we now don't need
an executeable stack any longer. PA-RISC is one of the last
architectures where an executeable stack was needed in oder to implement
the signal trampolines by putting assembly instructions on the stack
which then gets executed. Instead the kernel will provide the relevant
code in the vDSO page and only put the pointers to the signal
information on the stack.
By dropping the need for executable stacks we avoid running into issues
with applications which want non executable stacks for security reasons.
Additionally, alternative stacks on memory areas without exec
permissions are supported too.
This code is based on an initial implementation by Randolph Chung from 2006:
https://lore.kernel.org/linux-parisc/4544A34A.6080700@tausq.org/
I did the porting and lifted the code to current code base. Dave fixed
the unwind code so that gdb and glibc are able to backtrace through the
code. An additional patch to gdb will be pushed upstream by Dave.
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Dave Anglin <dave.anglin@bell.net>
Cc: Randolph Chung <randolph@tausq.org>
Signed-off-by: Helge Deller <deller@gmx.de>
Diffstat (limited to 'arch/parisc/include/asm/elf.h')
| -rw-r--r-- | arch/parisc/include/asm/elf.h | 15 |
1 files changed, 15 insertions, 0 deletions
diff --git a/arch/parisc/include/asm/elf.h b/arch/parisc/include/asm/elf.h index 3bd465a27791..cc426d365892 100644 --- a/arch/parisc/include/asm/elf.h +++ b/arch/parisc/include/asm/elf.h @@ -359,4 +359,19 @@ struct mm_struct; extern unsigned long arch_randomize_brk(struct mm_struct *); #define arch_randomize_brk arch_randomize_brk + +#define ARCH_HAS_SETUP_ADDITIONAL_PAGES 1 +struct linux_binprm; +extern int arch_setup_additional_pages(struct linux_binprm *bprm, + int executable_stack); +#define VDSO_AUX_ENT(a, b) NEW_AUX_ENT(a, b) +#define VDSO_CURRENT_BASE current->mm->context.vdso_base + +#define ARCH_DLINFO \ +do { \ + if (VDSO_CURRENT_BASE) { \ + NEW_AUX_ENT(AT_SYSINFO_EHDR, VDSO_CURRENT_BASE);\ + } \ +} while (0) + #endif |