5.4-stable review patch. If anyone has any objections, please let me know.
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From: Ryusuke Konishi konishi.ryusuke@gmail.com
commit 4aead50caf67e01020c8be1945c3201e8a972a27 upstream.
To prevent inodes with invalid file types from tripping through the vfs and causing malfunctions or assertion failures, add a missing sanity check when reading an inode from a block device. If the file type is not valid, treat it as a filesystem error.
Link: https://lkml.kernel.org/r/20250710134952.29862-1-konishi.ryusuke@gmail.com Fixes: 05fe58fdc10d ("nilfs2: inode operations") Signed-off-by: Ryusuke Konishi konishi.ryusuke@gmail.com Reported-by: syzbot+895c23f6917da440ed0d@syzkaller.appspotmail.com Link: https://syzkaller.appspot.com/bug?extid=895c23f6917da440ed0d Cc: stable@vger.kernel.org Signed-off-by: Andrew Morton akpm@linux-foundation.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- fs/nilfs2/inode.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-)
--- a/fs/nilfs2/inode.c +++ b/fs/nilfs2/inode.c @@ -525,11 +525,18 @@ static int __nilfs_read_inode(struct sup inode->i_op = &nilfs_symlink_inode_operations; inode_nohighmem(inode); inode->i_mapping->a_ops = &nilfs_aops; - } else { + } else if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode) || + S_ISFIFO(inode->i_mode) || S_ISSOCK(inode->i_mode)) { inode->i_op = &nilfs_special_inode_operations; init_special_inode( inode, inode->i_mode, huge_decode_dev(le64_to_cpu(raw_inode->i_device_code))); + } else { + nilfs_error(sb, + "invalid file type bits in mode 0%o for inode %lu", + inode->i_mode, ino); + err = -EIO; + goto failed_unmap; } nilfs_ifile_unmap_inode(root->ifile, ino, bh); brelse(bh);