From: Jun'ichi Nomura <j-nomura@ce.jp.nec.com>
Date: Fri, 24 Feb 2006 21:04:25 +0000 (-0800)
Subject: [PATCH] dm: free minor after unlink gendisk
X-Git-Tag: firefly_0821_release~37870
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=63d94e482df769f31e8b1097f06c3a3fba7bced4;p=firefly-linux-kernel-4.4.55.git

[PATCH] dm: free minor after unlink gendisk

Minor number should be freed after del_gendisk().  Otherwise, there could
be a window where 2 registered gendisk has same minor number.

Signed-off-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com>
Acked-by: Alasdair G Kergon <agk@redhat.com>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
---

diff --git a/drivers/md/dm.c b/drivers/md/dm.c
index dad9e403d59d..745ca1f67b14 100644
--- a/drivers/md/dm.c
+++ b/drivers/md/dm.c
@@ -849,14 +849,16 @@ static struct mapped_device *alloc_dev(unsigned int minor, int persistent)
 
 static void free_dev(struct mapped_device *md)
 {
+	unsigned int minor = md->disk->first_minor;
+
 	if (md->suspended_bdev) {
 		thaw_bdev(md->suspended_bdev, NULL);
 		bdput(md->suspended_bdev);
 	}
-	free_minor(md->disk->first_minor);
 	mempool_destroy(md->tio_pool);
 	mempool_destroy(md->io_pool);
 	del_gendisk(md->disk);
+	free_minor(minor);
 	put_disk(md->disk);
 	blk_put_queue(md->queue);
 	kfree(md);