On Fri, Sep 12, 2025 at 11:18:44PM +0900, Tetsuo Handa wrote:
> The inode mode loaded from corrupted disk can be invalid. Do like what
> commit 0a9e74051313 ("isofs: Verify inode mode when loading from disk")
> does.
>
> Reported-by: syzbot <syzbot+895c23f6917da440ed0d@xxxxxxxxxxxxxxxxxxxxxxxxx>
> Closes: https://syzkaller.appspot.com/bug?extid=895c23f6917da440ed0d
> Signed-off-by: Tetsuo Handa <penguin-kernel@xxxxxxxxxxxxxxxxxxx>
> ---
> This fix is similar to fixes for other filesystems, but got no response.
> Do we have to wait for Ack from Dave Kleikamp for another month?
Let's hope not, this is a validation issue...
> fs/jfs/inode.c | 8 +++++++-
> 1 file changed, 7 insertions(+), 1 deletion(-)
>
> diff --git a/fs/jfs/inode.c b/fs/jfs/inode.c
> index fcedeb514e14..21f3d029da7d 100644
> --- a/fs/jfs/inode.c
> +++ b/fs/jfs/inode.c
> @@ -59,9 +59,15 @@ struct inode *jfs_iget(struct super_block *sb, unsigned long ino)
> */
> inode->i_link[inode->i_size] = '\0';
> }
> - } 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 = &jfs_file_inode_operations;
> init_special_inode(inode, inode->i_mode, inode->i_rdev);
> + } else {
> + printk(KERN_DEBUG "JFS: Invalid file type 0%04o for inode %lu.\n",
> + inode->i_mode, inode->i_ino);
> + iget_failed(inode);
> + return ERR_PTR(-EIO);
...but how about EFSCORRUPTED instead of EIO here? Several filesystems
(xfs, ext*, erofs, f2fs, fuse, ocfs2, udf) return that for corrupt
metadata.
--D
> }
> unlock_new_inode(inode);
> return inode;
> --
> 2.51.0
>
>
