From: Yuriy M. Kaminskiy <yumkam@gmail.com>
Date: Thu, 7 Apr 2016 21:38:56 +0000 (+0300)
Subject: fsck: fix racing between unlock/unlink and open
X-Git-Tag: v2.29-rc1~278
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=fc75981a229a52ee8f5245c4a036dd151e4a70fc;p=thirdparty%2Futil-linux.git

fsck: fix racing between unlock/unlink and open

Process A	Process B	Process C
open()
[creates file]
lock()
[succeed]
		open()
		[open existing]
		lock()...
running()
close()
		[...succeed]
unlink()
		running()
				open()
				[creates file] {BAD!}
				lock()
				[succeed] {BAD!}
				running() {BAD!}
		close()

Cons: leaves empty (unlocked/harmless) .lock files in /run/fsck/
Signed-off-by: Yuriy M. Kaminskiy <yumkam@gmail.com>
---

diff --git a/disk-utils/fsck.c b/disk-utils/fsck.c
index 05cfbc4390..84d2dcc3d4 100644
--- a/disk-utils/fsck.c
+++ b/disk-utils/fsck.c
@@ -410,7 +410,6 @@ static void unlock_disk(struct fsck_instance *inst)
 		printf(_("Unlocking %s.\n"), inst->lockpath);
 
 	close(inst->lock);			/* unlock */
-	unlink(inst->lockpath);
 
 	free(inst->lockpath);