From: Desmond Cheong Zhi Xi desmondcheongzx@gmail.com
[ Upstream commit 16ee572eaf0d09daa4c8a755fdb71e40dbf8562d ]
Patch series "hfs: fix various errors", v2.
This series ultimately aims to address a lockdep warning in hfs_find_init reported by Syzbot [1].
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://syzkaller.appspot.com/bug?id=f007ef1d7a31a469e3be7aeb0fde0769b18585d... [1] 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 Signed-off-by: Linus Torvalds torvalds@linux-foundation.org Signed-off-by: Sasha Levin sashal@kernel.org --- fs/hfs/super.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-)
diff --git a/fs/hfs/super.c b/fs/hfs/super.c index 173876782f73..77b6f35a4aa9 100644 --- a/fs/hfs/super.c +++ b/fs/hfs/super.c @@ -427,14 +427,12 @@ static int hfs_fill_super(struct super_block *sb, void *data, int silent) 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); @@ -450,6 +448,8 @@ static int hfs_fill_super(struct super_block *sb, void *data, int silent) /* everything's okay */ return 0;
+bail_hfs_find: + hfs_find_exit(&fd); bail_no_root: pr_err("get root inode failed\n"); bail: