Home Home > GIT Browse
summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorRadu Caragea <sinaelgl@gmail.com>2013-08-21 20:55:59 +0300
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2013-08-29 09:47:39 -0700
commitff1a668bc01c811ffcf19a3d43af58d7bd658986 (patch)
tree1b498dbdba936624fc26f82dac0bd69082c3107d
parentbd4b69c1f7f58fc28fb636a3be006770edf58d68 (diff)
x86 get_unmapped_area: Access mmap_legacy_base through mm_struct member
commit 41aacc1eea645c99edbe8fbcf78a97dc9b862adc upstream. This is the updated version of df54d6fa5427 ("x86 get_unmapped_area(): use proper mmap base for bottom-up direction") that only randomizes the mmap base address once. Signed-off-by: Radu Caragea <sinaelgl@gmail.com> Reported-and-tested-by: Jeff Shorey <shoreyjeff@gmail.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Michel Lespinasse <walken@google.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Rik van Riel <riel@redhat.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Adrian Sendroiu <molecula2788@gmail.com> Cc: Kamal Mostafa <kamal@canonical.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-rw-r--r--arch/x86/kernel/sys_x86_64.c2
-rw-r--r--arch/x86/mm/mmap.c6
-rw-r--r--include/linux/mm_types.h1
3 files changed, 6 insertions, 3 deletions
diff --git a/arch/x86/kernel/sys_x86_64.c b/arch/x86/kernel/sys_x86_64.c
index dbded5aedb81..30277e27431a 100644
--- a/arch/x86/kernel/sys_x86_64.c
+++ b/arch/x86/kernel/sys_x86_64.c
@@ -101,7 +101,7 @@ static void find_start_end(unsigned long flags, unsigned long *begin,
*begin = new_begin;
}
} else {
- *begin = TASK_UNMAPPED_BASE;
+ *begin = current->mm->mmap_legacy_base;
*end = TASK_SIZE;
}
}
diff --git a/arch/x86/mm/mmap.c b/arch/x86/mm/mmap.c
index 845df6835f9f..5c1ae28825cd 100644
--- a/arch/x86/mm/mmap.c
+++ b/arch/x86/mm/mmap.c
@@ -112,12 +112,14 @@ static unsigned long mmap_legacy_base(void)
*/
void arch_pick_mmap_layout(struct mm_struct *mm)
{
+ mm->mmap_legacy_base = mmap_legacy_base();
+ mm->mmap_base = mmap_base();
+
if (mmap_is_legacy()) {
- mm->mmap_base = mmap_legacy_base();
+ mm->mmap_base = mm->mmap_legacy_base;
mm->get_unmapped_area = arch_get_unmapped_area;
mm->unmap_area = arch_unmap_area;
} else {
- mm->mmap_base = mmap_base();
mm->get_unmapped_area = arch_get_unmapped_area_topdown;
mm->unmap_area = arch_unmap_area_topdown;
}
diff --git a/include/linux/mm_types.h b/include/linux/mm_types.h
index ace9a5f01c64..4a189ba6b128 100644
--- a/include/linux/mm_types.h
+++ b/include/linux/mm_types.h
@@ -333,6 +333,7 @@ struct mm_struct {
void (*unmap_area) (struct mm_struct *mm, unsigned long addr);
#endif
unsigned long mmap_base; /* base of mmap area */
+ unsigned long mmap_legacy_base; /* base of mmap area in bottom-up allocations */
unsigned long task_size; /* size of task vm space */
unsigned long cached_hole_size; /* if non-zero, the largest hole below free_area_cache */
unsigned long free_area_cache; /* first hole of size cached_hole_size or larger */