Re: [PATCH 2/2] hfsplus: add a check for hfs_bnode_find

["Ernesto A. Fernández" <ernesto.mnd.fernandez@gmail.com>]

Hi,

On Wed, Oct 16, 2019 at 08:06:20PM +0800, Chuhong Yuan wrote:
> hfs_brec_update_parent misses a check for hfs_bnode_find and may miss
> the failure.
> Add a check for it like what is done in again.
> 
> Signed-off-by: Chuhong Yuan <hslester96@gmail.com>
> ---
>  fs/hfsplus/brec.c | 2 ++
>  1 file changed, 2 insertions(+)
> 
> diff --git a/fs/hfsplus/brec.c b/fs/hfsplus/brec.c
> index 1918544a7871..22bada8288c4 100644
> --- a/fs/hfsplus/brec.c
> +++ b/fs/hfsplus/brec.c
> @@ -434,6 +434,8 @@ static int hfs_brec_update_parent(struct hfs_find_data *fd)
>  			new_node->parent = tree->root;
>  		}
>  		fd->bnode = hfs_bnode_find(tree, new_node->parent);
> +		if (IS_ERR(fd->bnode))
> +			return PTR_ERR(fd->bnode);

You shouldn't just return here, you still hold a reference to new_node.
The call to hfs_bnode_find() after the again label seems to be making a
similar mistake.

I don't think either one can actually fail though, because the parent
nodes have all been read and hashed before, haven't they?

>  		/* create index key and entry */
>  		hfs_bnode_read_key(new_node, fd->search_key, 14);
>  		cnid = cpu_to_be32(new_node->this);
> -- 
> 2.20.1
>