4.9-stable patches

[thirdparty/kernel/stable-queue.git] / releases / 3.1.5 / hugetlb-release-pages-in-the-error-path-of-hugetlb_cow.patch

From ea4039a34c4c206d015d34a49d0b00868e37db1d Mon Sep 17 00:00:00 2001
From: Hillf Danton <dhillf@gmail.com>
Date: Tue, 15 Nov 2011 14:36:12 -0800
Subject: hugetlb: release pages in the error path of hugetlb_cow()

From: Hillf Danton <dhillf@gmail.com>

commit ea4039a34c4c206d015d34a49d0b00868e37db1d upstream.

If we fail to prepare an anon_vma, the {new, old}_page should be released,
or they will leak.

Signed-off-by: Hillf Danton <dhillf@gmail.com>
Reviewed-by: Andrea Arcangeli <aarcange@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Johannes Weiner <jweiner@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Michal Hocko <mhocko@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

---
 mm/hugetlb.c |    2 ++
 1 file changed, 2 insertions(+)

--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -2422,6 +2422,8 @@ retry_avoidcopy:
 	 * anon_vma prepared.
 	 */
 	if (unlikely(anon_vma_prepare(vma))) {
+		page_cache_release(new_page);
+		page_cache_release(old_page);
 		/* Caller expects lock to be held */
 		spin_lock(&mm->page_table_lock);
 		return VM_FAULT_OOM;