From: Oleg Nesterov <oleg@tv-sign.ru>
Date: Fri, 4 Jul 2008 16:59:28 +0000 (-0700)
Subject: get_user_pages(): fix possible page leak on oom
X-Git-Tag: firefly_0821_release~19823
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=7a36a752d006f6874049da510297eeb7f09d92a7;p=firefly-linux-kernel-4.4.55.git

get_user_pages(): fix possible page leak on oom

get_user_pages() must not return the error when i != 0.  When pages !=
NULL we have i get_page()'ed pages.

Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Acked-by: Nick Piggin <npiggin@suse.de>
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 350e646032f5..2302d228fe04 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -1151,7 +1151,7 @@ int get_user_pages(struct task_struct *tsk, struct mm_struct *mm,
 			 * be processed until returning to user space.
 			 */
 			if (unlikely(test_tsk_thread_flag(tsk, TIF_MEMDIE)))
-				return -ENOMEM;
+				return i ? i : -ENOMEM;
 
 			if (write)
 				foll_flags |= FOLL_WRITE;