summaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
authorAndi Kleen <ak@suse.de>2006-05-30 22:47:45 +0200
committerLinus Torvalds <torvalds@g5.osdl.org>2006-05-30 20:31:05 -0700
commit6ae53cd496d36db5f25e6f84b8b9fe7e675999a1 (patch)
tree298b1b2c498c5d8e95954809b9bd3890a92ac0fb
parent3793c65c13e4751c7a10f98198bae1758453eb0e (diff)
downloadlinux-6ae53cd496d36db5f25e6f84b8b9fe7e675999a1.tar.bz2
[PATCH] x86_64: Fix stack/mmap randomization for compat tasks
ia32_setup_arg_pages would ignore the passed in random stack top and use its own static value. Now it uses the 8bit of randomness native i386 would use too. This indirectly fixes mmap randomization for 32bit processes too, which depends on the stack randomization. Should also give slightly better virtual cache colouring and possibly better performance with HyperThreading. Signed-off-by: Andi Kleen <ak@suse.de> Acked-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
-rw-r--r--arch/x86_64/ia32/ia32_binfmt.c4
-rw-r--r--include/asm-x86_64/elf.h2
2 files changed, 3 insertions, 3 deletions
diff --git a/arch/x86_64/ia32/ia32_binfmt.c b/arch/x86_64/ia32/ia32_binfmt.c
index e776139afb20..926c4743d13b 100644
--- a/arch/x86_64/ia32/ia32_binfmt.c
+++ b/arch/x86_64/ia32/ia32_binfmt.c
@@ -339,7 +339,7 @@ int ia32_setup_arg_pages(struct linux_binprm *bprm, unsigned long stack_top,
struct mm_struct *mm = current->mm;
int i, ret;
- stack_base = IA32_STACK_TOP - MAX_ARG_PAGES * PAGE_SIZE;
+ stack_base = stack_top - MAX_ARG_PAGES * PAGE_SIZE;
mm->arg_start = bprm->p + stack_base;
bprm->p += stack_base;
@@ -357,7 +357,7 @@ int ia32_setup_arg_pages(struct linux_binprm *bprm, unsigned long stack_top,
{
mpnt->vm_mm = mm;
mpnt->vm_start = PAGE_MASK & (unsigned long) bprm->p;
- mpnt->vm_end = IA32_STACK_TOP;
+ mpnt->vm_end = stack_top;
if (executable_stack == EXSTACK_ENABLE_X)
mpnt->vm_flags = VM_STACK_FLAGS | VM_EXEC;
else if (executable_stack == EXSTACK_DISABLE_X)
diff --git a/include/asm-x86_64/elf.h b/include/asm-x86_64/elf.h
index c98633af07d2..b4f8f4a41a6e 100644
--- a/include/asm-x86_64/elf.h
+++ b/include/asm-x86_64/elf.h
@@ -159,7 +159,7 @@ extern int dump_task_fpu (struct task_struct *, elf_fpregset_t *);
#define ELF_CORE_COPY_FPREGS(tsk, elf_fpregs) dump_task_fpu(tsk, elf_fpregs)
/* 1GB for 64bit, 8MB for 32bit */
-#define STACK_RND_MASK (is_compat_task() ? 0x7ff : 0x3fffff)
+#define STACK_RND_MASK (test_thread_flag(TIF_IA32) ? 0x7ff : 0x3fffff)
#endif