mm/mlock.c: change count_mm_mlocked_page_nr return type

On a 64-bit machine the value of "vma->vm_end - vma->vm_start" may be
negative when using 32 bit ints and the "count >> PAGE_SHIFT"'s result
will be wrong.  So change the local variable and return value to
unsigned long to fix the problem.

Link: http://lkml.kernel.org/r/20190513023701.83056-1-swkhack@gmail.com
Fixes: 0cf2f6f6dc ("mm: mlock: check against vma for actual mlock() size")
Signed-off-by: swkhack <swkhack@gmail.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
swkhack 2019-06-13 15:56:08 -07:00 committed by Linus Torvalds
parent 7a30df49f6
commit 0874bb49bb
1 changed files with 2 additions and 2 deletions

View File

@ -636,11 +636,11 @@ static int apply_vma_lock_flags(unsigned long start, size_t len,
* is also counted.
* Return value: previously mlocked page counts
*/
static int count_mm_mlocked_page_nr(struct mm_struct *mm,
static unsigned long count_mm_mlocked_page_nr(struct mm_struct *mm,
unsigned long start, size_t len)
{
struct vm_area_struct *vma;
int count = 0;
unsigned long count = 0;
if (mm == NULL)
mm = current->mm;