linux/fs/hfs
Desmond Cheong Zhi Xi b3b2177a2d hfs: add lock nesting notation to hfs_find_init
Syzbot reports a possible recursive lock in [1].

This happens due to missing lock nesting information.  From the logs, we
see that a call to hfs_fill_super is made to mount the hfs filesystem.
While searching for the root inode, the lock on the catalog btree is
grabbed.  Then, when the parent of the root isn't found, a call to
__hfs_bnode_create is made to create the parent of the root.  This
eventually leads to a call to hfs_ext_read_extent which grabs a lock on
the extents btree.

Since the order of locking is catalog btree -> extents btree, this lock
hierarchy does not lead to a deadlock.

To tell lockdep that this locking is safe, we add nesting notation to
distinguish between catalog btrees, extents btrees, and attributes
btrees (for HFS+).  This has already been done in hfsplus.

Link: https://syzkaller.appspot.com/bug?id=f007ef1d7a31a469e3be7aeb0fde0769b18585db [1]
Link: https://lkml.kernel.org/r/20210701030756.58760-4-desmondcheongzx@gmail.com
Signed-off-by: Desmond Cheong Zhi Xi <desmondcheongzx@gmail.com>
Reported-by: syzbot+b718ec84a87b7e73ade4@syzkaller.appspotmail.com
Tested-by: syzbot+b718ec84a87b7e73ade4@syzkaller.appspotmail.com
Reviewed-by: Viacheslav Dubeyko <slava@dubeyko.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Gustavo A. R. Silva <gustavoars@kernel.org>
Cc: Shuah Khan <skhan@linuxfoundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-07-15 10:13:49 -07:00
..
attr.c acl: handle idmapped mounts 2021-01-24 14:27:17 +01:00
bfind.c hfs: add lock nesting notation to hfs_find_init 2021-07-15 10:13:49 -07:00
bitmap.c
bnode.c hfs: fix high memory mapping in hfs_bnode_read 2021-07-15 10:13:49 -07:00
brec.c
btree.c hfs: do not free node before using 2018-11-30 14:56:14 -08:00
btree.h hfs: add lock nesting notation to hfs_find_init 2021-07-15 10:13:49 -07:00
catalog.c
dir.c fs: make helpers idmap mount aware 2021-01-24 14:27:20 +01:00
extent.c
hfs_fs.h fs: make helpers idmap mount aware 2021-01-24 14:27:20 +01:00
hfs.h
inode.c mm: require ->set_page_dirty to be explicitly wired up 2021-06-29 10:53:48 -07:00
Kconfig docs: filesystems: fix renamed references 2020-04-20 15:45:22 -06:00
Makefile treewide: Add SPDX license identifier - Makefile/Kconfig 2019-05-21 10:50:46 +02:00
mdb.c hfs: stop using ioctl_by_bdev 2020-05-09 16:15:13 -06:00
part_tbl.c
string.c
super.c hfs: add missing clean-up in hfs_fill_super 2021-07-15 10:13:49 -07:00
sysdep.c
trans.c