diff mbox series

[10/13] hfs: add missing clean-up in hfs_fill_super

Message ID 20210715042701.RIM_Afm8q%akpm@linux-foundation.org (mailing list archive)
State New
Headers show
Series [01/13] mm: move helper to check slub_debug_enabled | expand

Commit Message

Andrew Morton July 15, 2021, 4:27 a.m. UTC 
From: Desmond Cheong Zhi Xi <desmondcheongzx@gmail.com>
Subject: hfs: add missing clean-up in hfs_fill_super

Patch series "hfs: fix various errors", v2.

This series ultimately aims to address a lockdep warning in hfs_find_init
reported by Syzbot:
https://syzkaller.appspot.com/bug?id=f007ef1d7a31a469e3be7aeb0fde0769b18585db

The work done for this led to the discovery of another bug, and the
Syzkaller repro test also reveals an invalid memory access error after
clearing the lockdep warning.  Hence, this series is broken up into three
patches:

1. Add a missing call to hfs_find_exit for an error path in
   hfs_fill_super

2. Fix memory mapping in hfs_bnode_read by fixing calls to kmap

3. Add lock nesting notation to tell lockdep that the observed locking
   hierarchy is safe


This patch (of 3):

Before exiting hfs_fill_super, the struct hfs_find_data used in
hfs_find_init should be passed to hfs_find_exit to be cleaned up, and to
release the lock held on the btree.

The call to hfs_find_exit is missing from an error path.  We add it back
in by consolidating calls to hfs_find_exit for error paths.

Link: https://lkml.kernel.org/r/20210701030756.58760-1-desmondcheongzx@gmail.com
Link: https://lkml.kernel.org/r/20210701030756.58760-2-desmondcheongzx@gmail.com
Signed-off-by: Desmond Cheong Zhi Xi <desmondcheongzx@gmail.com>
Reviewed-by: Viacheslav Dubeyko <slava@dubeyko.com>
Cc: Gustavo A. R. Silva <gustavoars@kernel.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Shuah Khan <skhan@linuxfoundation.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 fs/hfs/super.c |   10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)
diff mbox series

Patch

--- a/fs/hfs/super.c~hfs-add-missing-clean-up-in-hfs_fill_super
+++ a/fs/hfs/super.c
@@ -420,14 +420,12 @@  static int hfs_fill_super(struct super_b
 	if (!res) {
 		if (fd.entrylength > sizeof(rec) || fd.entrylength < 0) {
 			res =  -EIO;
-			goto bail;
+			goto bail_hfs_find;
 		}
 		hfs_bnode_read(fd.bnode, &rec, fd.entryoffset, fd.entrylength);
 	}
-	if (res) {
-		hfs_find_exit(&fd);
-		goto bail_no_root;
-	}
+	if (res)
+		goto bail_hfs_find;
 	res = -EINVAL;
 	root_inode = hfs_iget(sb, &fd.search_key->cat, &rec);
 	hfs_find_exit(&fd);
@@ -443,6 +441,8 @@  static int hfs_fill_super(struct super_b
 	/* everything's okay */
 	return 0;
 
+bail_hfs_find:
+	hfs_find_exit(&fd);
 bail_no_root:
 	pr_err("get root inode failed\n");
 bail: