mm: use long type for page counts in mm_populate() and get_user_pages()
Use long type for page counts in mm_populate() so as to avoid integer
overflow when running the following test code:
int main(void) {
void *p = mmap(NULL, 0x100000000000, PROT_READ,
MAP_PRIVATE | MAP_ANON, -1, 0);
printf("p: %p\n", p);
mlockall(MCL_CURRENT);
printf("done\n");
return 0;
}
Signed-off-by: Michel Lespinasse <walken@google.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/mm/memory.c b/mm/memory.c
index 7bd22a6..bc929db 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -1677,15 +1677,15 @@
* instead of __get_user_pages. __get_user_pages should be used only if
* you need some special @gup_flags.
*/
-int __get_user_pages(struct task_struct *tsk, struct mm_struct *mm,
- unsigned long start, int nr_pages, unsigned int gup_flags,
- struct page **pages, struct vm_area_struct **vmas,
- int *nonblocking)
+long __get_user_pages(struct task_struct *tsk, struct mm_struct *mm,
+ unsigned long start, unsigned long nr_pages,
+ unsigned int gup_flags, struct page **pages,
+ struct vm_area_struct **vmas, int *nonblocking)
{
- int i;
+ long i;
unsigned long vm_flags;
- if (nr_pages <= 0)
+ if (!nr_pages)
return 0;
VM_BUG_ON(!!pages != !!(gup_flags & FOLL_GET));
@@ -1981,9 +1981,9 @@
*
* See also get_user_pages_fast, for performance critical applications.
*/
-int get_user_pages(struct task_struct *tsk, struct mm_struct *mm,
- unsigned long start, int nr_pages, int write, int force,
- struct page **pages, struct vm_area_struct **vmas)
+long get_user_pages(struct task_struct *tsk, struct mm_struct *mm,
+ unsigned long start, unsigned long nr_pages, int write,
+ int force, struct page **pages, struct vm_area_struct **vmas)
{
int flags = FOLL_TOUCH;