[PATCH v2 0/3] hfs: fix various errors

Desmond Cheong Zhi Xi desmondcheongzx at gmail.com
Thu Jul 1 03:07:53 UTC 2021


Hi,

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

v1 -> v2:
Patch 1: Consolidated calls to hfs_find_exit on error paths in hfs_fill_super, as suggested by Viacheslav Dubeyko.
Patch 2: Added safety checks, clarified code, and switched from kmap/kunmap to kmap_atomic/kunmap_atomic, as suggested by Viacheslav Dubeyko.

Desmond Cheong Zhi Xi (3):
  hfs: add missing clean-up in hfs_fill_super
  hfs: fix high memory mapping in hfs_bnode_read
  hfs: add lock nesting notation to hfs_find_init

 fs/hfs/bfind.c | 14 +++++++++++++-
 fs/hfs/bnode.c | 25 ++++++++++++++++++++-----
 fs/hfs/btree.h |  7 +++++++
 fs/hfs/super.c | 10 +++++-----
 4 files changed, 45 insertions(+), 11 deletions(-)

-- 
2.25.1



More information about the Linux-kernel-mentees mailing list