The patch titled
Subject: mm/gup: mark lock taken only after a successful retake
has been removed from the -mm tree. Its filename was
mm-gup-mark-lock-taken-only-after-a-successful-retake.patch
This patch was dropped because it was merged into mainline or a subsystem tree
------------------------------------------------------
From: Peter Xu <peterx@xxxxxxxxxx>
Subject: mm/gup: mark lock taken only after a successful retake
It's definitely incorrect to mark the lock as taken even if
down_read_killable() failed. It's overlooked when we switched from
down_read() to down_read_killable() because down_read() won't fail while
down_read_killable() could.
Link: http://lkml.kernel.org/r/20200407204754.GA66033@xz-x1
Fixes: 71335f37c5e8 ("mm/gup: allow to react to fatal signals")
Signed-off-by: Peter Xu <peterx@xxxxxxxxxx>
Reported-by: syzbot+a8c70b7f3579fc0587dc@xxxxxxxxxxxxxxxxxxxxxxxxx
Tested-by: syzbot+a8c70b7f3579fc0587dc@xxxxxxxxxxxxxxxxxxxxxxxxx
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
mm/gup.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/mm/gup.c~mm-gup-mark-lock-taken-only-after-a-successful-retake
+++ a/mm/gup.c
@@ -1329,7 +1329,6 @@ retry:
if (fatal_signal_pending(current))
break;
- *locked = 1;
ret = down_read_killable(&mm->mmap_sem);
if (ret) {
BUG_ON(ret > 0);
@@ -1338,6 +1337,7 @@ retry:
break;
}
+ *locked = 1;
ret = __get_user_pages(tsk, mm, start, 1, flags | FOLL_TRIED,
pages, NULL, locked);
if (!*locked) {
_
Patches currently in -mm which might be from peterx@xxxxxxxxxx are
