diff options
| author | Arun Chandran <achandran@mvista.com> | 2014-10-10 15:31:24 +0400 |
|---|---|---|
| committer | Catalin Marinas <catalin.marinas@arm.com> | 2014-10-24 18:47:49 +0400 |
| commit | 92980405f3537136b8e81007a9df576762f49bbb (patch) | |
| tree | a40d98e18e154c3d04e673842864812e14425c08 | |
| parent | e2b6b35ee77522c2e15e770aded0b05c25ca0616 (diff) | |
| download | linux-92980405f3537136b8e81007a9df576762f49bbb.tar.xz | |
arm64: ASLR: Don't randomise text when randomise_va_space == 0
When user asks to turn off ASLR by writing "0" to
/proc/sys/kernel/randomize_va_space there should not be
any randomization to mmap base, stack, VDSO, libs, text and heap
Currently arm64 violates this behavior by randomising text.
Fix this by defining a constant ELF_ET_DYN_BASE. The randomisation of
mm->mmap_base is done by setup_new_exec -> arch_pick_mmap_layout ->
mmap_base -> mmap_rnd.
Signed-off-by: Arun Chandran <achandran@mvista.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
| -rw-r--r-- | arch/arm64/Kconfig | 1 | ||||
| -rw-r--r-- | arch/arm64/include/asm/elf.h | 4 | ||||
| -rw-r--r-- | arch/arm64/kernel/process.c | 5 |
3 files changed, 3 insertions, 7 deletions
diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index b8053be1d803..9532f8d5857e 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -1,5 +1,6 @@ config ARM64 def_bool y + select ARCH_BINFMT_ELF_RANDOMIZE_PIE select ARCH_HAS_ATOMIC64_DEC_IF_POSITIVE select ARCH_HAS_SG_CHAIN select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST diff --git a/arch/arm64/include/asm/elf.h b/arch/arm64/include/asm/elf.h index 01d3aab64b79..1f65be393139 100644 --- a/arch/arm64/include/asm/elf.h +++ b/arch/arm64/include/asm/elf.h @@ -126,7 +126,7 @@ typedef struct user_fpsimd_state elf_fpregset_t; * that it will "exec", and that there is sufficient room for the brk. */ extern unsigned long randomize_et_dyn(unsigned long base); -#define ELF_ET_DYN_BASE (randomize_et_dyn(2 * TASK_SIZE_64 / 3)) +#define ELF_ET_DYN_BASE (2 * TASK_SIZE_64 / 3) /* * When the program starts, a1 contains a pointer to a function to be @@ -169,7 +169,7 @@ extern unsigned long arch_randomize_brk(struct mm_struct *mm); #define COMPAT_ELF_PLATFORM ("v8l") #endif -#define COMPAT_ELF_ET_DYN_BASE (randomize_et_dyn(2 * TASK_SIZE_32 / 3)) +#define COMPAT_ELF_ET_DYN_BASE (2 * TASK_SIZE_32 / 3) /* AArch32 registers. */ #define COMPAT_ELF_NGREG 18 diff --git a/arch/arm64/kernel/process.c b/arch/arm64/kernel/process.c index c3065dbc4fa2..fde9923af859 100644 --- a/arch/arm64/kernel/process.c +++ b/arch/arm64/kernel/process.c @@ -378,8 +378,3 @@ unsigned long arch_randomize_brk(struct mm_struct *mm) { return randomize_base(mm->brk); } - -unsigned long randomize_et_dyn(unsigned long base) -{ - return randomize_base(base); -} |