[PATCH for review] [33/145] i386/x86-64: Don't randomize stack top when no randomization personality is set

Andi Kleen
2006-08-10T19:36:30Z

r

Based on patch from Frank van Maarseveen <frankvm@frankvm.com>, but
extended.

Signed-off-by: Andi Kleen <ak@suse.de>

---
arch/i386/kernel/process.c | 3 ++-
arch/x86_64/kernel/process.c | 2 +-
fs/binfmt_elf.c | 3 ++-
3 files changed, 5 insertions(+), 3 deletions(-)

Index: linux/arch/x86_64/kernel/process.c
===================================================================
--- linux.orig/arch/x86_64/kernel/process.c
+++ linux/arch/x86_64/kernel/process.c
@@ -845,7 +845,7 @@ int dump_task_regs(struct task_struct *t

unsigned long arch_align_stack(unsigned long sp)
{
- if (randomize_va_space)
+ if (!(current->personality & ADDR_NO_RANDOMIZE) && randomize_va_space)
sp -= get_random_int() % 8192;
return sp & ~0xf;
}
Index: linux/arch/i386/kernel/process.c
===================================================================
--- linux.orig/arch/i386/kernel/process.c
+++ linux/arch/i386/kernel/process.c
@@ -37,6 +37,7 @@
#include <linux/kallsyms.h>
#include <linux/ptrace.h>
#include <linux/random.h>
+#include <linux/personality.h>

#include <asm/uaccess.h>
#include <asm/pgtable.h>
@@ -905,7 +906,7 @@ asmlinkage int sys_get_thread_area(struc

unsigned long arch_align_stack(unsigned long sp)
{
- if (randomize_va_space)
+ if (!(current->personality & ADDR_NO_RANDOMIZE) && randomize_va_space)
sp -= get_random_int() % 8192;
return sp & ~0xf;
}
Index: linux/fs/binfmt_elf.c
===================================================================
--- linux.orig/fs/binfmt_elf.c
+++ linux/fs/binfmt_elf.c
@@ -515,7 +515,8 @@ static unsigned long randomize_stack_top
{
unsigned int random_variable = 0;

- if (current->flags & PF_RANDOMIZE) {
+ if ((current->flags & PF_RANDOMIZE) &&
+ !(current->personality & ADDR_NO_RANDOMIZE)) {
random_variable = get_random_int() & STACK_RND_MASK;
random_variable <<= PAGE_SHIFT;
}