The patch titled Subject: nilfs2: fix NULL pointer dereference at nilfs_bmap_lookup_at_level() has been added to the -mm mm-hotfixes-unstable branch. Its filename is nilfs2-fix-null-pointer-dereference-at-nilfs_bmap_lookup_at_level.patch This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/nilfs2-fix-null-pointer-dereference-at-nilfs_bmap_lookup_at_level.patch This patch will later appear in the mm-hotfixes-unstable branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/process/submit-checklist.rst when testing your code *** The -mm tree is included into linux-next via the mm-everything branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm and is updated there every 2-3 working days ------------------------------------------------------ From: Ryusuke Konishi <konishi.ryusuke@xxxxxxxxx> Subject: nilfs2: fix NULL pointer dereference at nilfs_bmap_lookup_at_level() Date: Sun, 2 Oct 2022 12:08:04 +0900 If the i_mode field in inode of metadata files is corrupted on disk, it can cause the initialization of bmap structure, which should have been called from nilfs_read_inode_common(), not to be called. This causes a lockdep warning followed by a NULL pointer dereference at nilfs_bmap_lookup_at_level(). This patch fixes these issues by adding a missing sanitiy check for the i_mode field of metadata file's inode. Link: https://lkml.kernel.org/r/20221002030804.29978-1-konishi.ryusuke@xxxxxxxxx Signed-off-by: Ryusuke Konishi <konishi.ryusuke@xxxxxxxxx> Reported-by: syzbot+2b32eb36c1a825b7a74c@xxxxxxxxxxxxxxxxxxxxxxxxx Reported-by: Tetsuo Handa <penguin-kernel@xxxxxxxxxxxxxxxxxxx> Tested-by: Ryusuke Konishi <konishi.ryusuke@xxxxxxxxx> Cc: <stable@xxxxxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- fs/nilfs2/inode.c | 2 ++ 1 file changed, 2 insertions(+) --- a/fs/nilfs2/inode.c~nilfs2-fix-null-pointer-dereference-at-nilfs_bmap_lookup_at_level +++ a/fs/nilfs2/inode.c @@ -455,6 +455,8 @@ int nilfs_read_inode_common(struct inode inode->i_atime.tv_nsec = le32_to_cpu(raw_inode->i_mtime_nsec); inode->i_ctime.tv_nsec = le32_to_cpu(raw_inode->i_ctime_nsec); inode->i_mtime.tv_nsec = le32_to_cpu(raw_inode->i_mtime_nsec); + if (nilfs_is_metadata_file_inode(inode) && !S_ISREG(inode->i_mode)) + return -EIO; /* this inode is for metadata and corrupted */ if (inode->i_nlink == 0) return -ESTALE; /* this inode is deleted */ _ Patches currently in -mm which might be from konishi.ryusuke@xxxxxxxxx are nilfs2-fix-use-after-free-bug-of-struct-nilfs_root.patch nilfs2-fix-null-pointer-dereference-at-nilfs_bmap_lookup_at_level.patch nilfs2-replace-warn_ons-by-nilfs_error-for-checkpoint-acquisition-failure.patch