[PATCH 4.4 91/92] hfsplus: stop workqueue when fill_super() failed

From: Greg Kroah-Hartman
Date: Thu May 24 2018 - 04:53:53 EST


4.4-stable review patch. If anyone has any objections, please let me know.

------------------

From: Tetsuo Handa <penguin-kernel@xxxxxxxxxxxxxxxxxxx>

commit 66072c29328717072fd84aaff3e070e3f008ba77 upstream.

syzbot is reporting ODEBUG messages at hfsplus_fill_super() [1]. This
is because hfsplus_fill_super() forgot to call cancel_delayed_work_sync().

As far as I can see, it is hfsplus_mark_mdb_dirty() from
hfsplus_new_inode() in hfsplus_fill_super() that calls
queue_delayed_work(). Therefore, I assume that hfsplus_new_inode() does
not fail if queue_delayed_work() was called, and the out_put_hidden_dir
label is the appropriate location to call cancel_delayed_work_sync().

[1] https://syzkaller.appspot.com/bug?id=a66f45e96fdbeb76b796bf46eb25ea878c42a6c9

Link: http://lkml.kernel.org/r/964a8b27-cd69-357c-fe78-76b066056201@xxxxxxxxxxxxxxxxxxx
Signed-off-by: Tetsuo Handa <penguin-kernel@xxxxxxxxxxxxxxxxxxx>
Reported-by: syzbot <syzbot+4f2e5f086147d543ab03@xxxxxxxxxxxxxxxxxxxxxxxxx>
Cc: Al Viro <viro@xxxxxxxxxxxxxxxxxx>
Cc: David Howells <dhowells@xxxxxxxxxx>
Cc: Ernesto A. Fernandez <ernesto.mnd.fernandez@xxxxxxxxx>
Cc: Vyacheslav Dubeyko <slava@xxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
fs/hfsplus/super.c | 1 +
1 file changed, 1 insertion(+)

--- a/fs/hfsplus/super.c
+++ b/fs/hfsplus/super.c
@@ -585,6 +585,7 @@ static int hfsplus_fill_super(struct sup
return 0;

out_put_hidden_dir:
+ cancel_delayed_work_sync(&sbi->sync_work);
iput(sbi->hidden_dir);
out_put_root:
dput(sb->s_root);