mirrors/linux
1
0
Fork 1
mirror of https://github.com/torvalds/linux.git synced 2025-11-04 10:40:15 +02:00
Code Issues Projects Releases Packages Wiki Activity Actions

x86 get_unmapped_area(): use proper mmap base for bottom-up direction

Browse source 
When the stack is set to unlimited, the bottomup direction is used for
mmap-ings but the mmap_base is not used and thus effectively renders
ASLR for mmapings along with PIE useless.

Cc: Michel Lespinasse <walken@google.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Reviewed-by: Rik van Riel <riel@redhat.com>
Acked-by: Ingo Molnar <mingo@kernel.org>
Cc: Adrian Sendroiu <molecula2788@gmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Radu Caragea 2013-08-13 16:00:59 -07:00 committed by Linus Torvalds
parent c7dd3392ad
commit df54d6fa54
3 changed files with 3 additions and 2 deletions
repo.diff.show_diff_stats Download patch file Download diff file Expand all files Collapse all files

2
arch/x86/kernel/sys_x86_64.c
View file

@ -101,7 +101,7 @@ static void find_start_end(unsigned long flags, unsigned long *begin,
*begin = new_begin;
}
} else {
*begin = TASK_UNMAPPED_BASE;
*begin = mmap_legacy_base();
*end = TASK_SIZE;
}
}

2
arch/x86/mm/mmap.c
View file

@ -98,7 +98,7 @@ static unsigned long mmap_base(void)
* Bottom-up (legacy) layout on X86_32 did not support randomization, X86_64
* does, but not when emulating X86_32
*/
static unsigned long mmap_legacy_base(void)
unsigned long mmap_legacy_base(void)
{
if (mmap_is_ia32())
return TASK_UNMAPPED_BASE;

1
include/linux/sched.h
View file

@ -314,6 +314,7 @@ struct nsproxy;
struct user_namespace;
#ifdef CONFIG_MMU
extern unsigned long mmap_legacy_base(void);
extern void arch_pick_mmap_layout(struct mm_struct *mm);
extern unsigned long
arch_get_unmapped_area(struct file *, unsigned long, unsigned long,