Re: [PATCH (REPOST)] hfs: don't use BUG() when we can continue

[Matthew Wilcox <willy@infradead.org>]

On Thu, Dec 05, 2024 at 10:45:11PM +0900, Tetsuo Handa wrote:
> syzkaller can mount crafted filesystem images.
> Don't crash the kernel when we can continue.

The one in hfs_test_inode() makes sense, but we should never get to
hfs_release_folio() or hfs_write_inode() with a bad inode, even with a
corrupted fs.  Right?

> +++ b/fs/hfs/inode.c
> @@ -81,7 +81,7 @@ static bool hfs_release_folio(struct folio *folio, gfp_t mask)
>  		tree = HFS_SB(sb)->cat_tree;
>  		break;
>  	default:
> -		BUG();
> +		pr_warn("unexpected inode %lu at %s()\n", inode->i_ino, __func__);
>  		return false;
>  	}
>  
> @@ -305,7 +305,7 @@ static int hfs_test_inode(struct inode *inode, void *data)
>  	case HFS_CDR_FIL:
>  		return inode->i_ino == be32_to_cpu(rec->file.FlNum);
>  	default:
> -		BUG();
> +		pr_warn("unexpected type %u at %s()\n", rec->type, __func__);
>  		return 1;
>  	}
>  }
> @@ -441,7 +441,7 @@ int hfs_write_inode(struct inode *inode, struct writeback_control *wbc)
>  			hfs_btree_write(HFS_SB(inode->i_sb)->cat_tree);
>  			return 0;
>  		default:
> -			BUG();
> +			pr_warn("unexpected inode %lu at %s()\n", inode->i_ino, __func__);
>  			return -EIO;
>  		}
>  	}
> -- 
> 2.47.0
> 
>