Re: [PATCH 1/2] xfs_repair: Fix check_refcount() error path

["Darrick J. Wong" <djwong@kernel.org>]

On Fri, Sep 02, 2022 at 03:43:39PM +0200, Carlos Maiolino wrote:
> From: Carlos Maiolino <cmaiolino@redhat.com>
> 
> Add proper exit error paths to avoid checking all pointers at the current path
> 
> Fixes-coverity-id: 1512651
> 
> Signed-off-by: Carlos Maiolino <cmaiolino@redhat.com>
> ---
>  repair/rmap.c |   23 +++++++++++------------
>  1 file changed, 11 insertions(+), 12 deletions(-)
> 
> diff --git a/repair/rmap.c b/repair/rmap.c
> index a7c4b25b1..0253c0c36 100644
> --- a/repair/rmap.c
> +++ b/repair/rmap.c
> @@ -1377,7 +1377,7 @@ check_refcounts(
>  	if (error) {
>  		do_warn(_("Could not read AGF %u to check refcount btree.\n"),
>  				agno);
> -		goto err;
> +		goto err_agf;

Shouldn't this       ^^^^^^^ be err_pag, since we're erroring out and
releasing the perag group reference?

Also ... don't the "if (XXX) free(XXX)" bits take care of all this?

(I can't access Coverity any more, so I don't know what's in the
report.)

--D

>  	}
>  
>  	/* Leave the per-ag data "uninitialized" since we rewrite it later */
> @@ -1386,7 +1386,7 @@ check_refcounts(
>  	bt_cur = libxfs_refcountbt_init_cursor(mp, NULL, agbp, pag);
>  	if (!bt_cur) {
>  		do_warn(_("Not enough memory to check refcount data.\n"));
> -		goto err;
> +		goto err_bt_cur;
>  	}
>  
>  	rl_rec = pop_slab_cursor(rl_cur);
> @@ -1398,7 +1398,7 @@ check_refcounts(
>  			do_warn(
>  _("Could not read reference count record for (%u/%u).\n"),
>  					agno, rl_rec->rc_startblock);
> -			goto err;
> +			goto err_loop;
>  		}
>  		if (!have) {
>  			do_warn(
> @@ -1413,7 +1413,7 @@ _("Missing reference count record for (%u/%u) len %u count %u\n"),
>  			do_warn(
>  _("Could not read reference count record for (%u/%u).\n"),
>  					agno, rl_rec->rc_startblock);
> -			goto err;
> +			goto err_loop;
>  		}
>  		if (!i) {
>  			do_warn(
> @@ -1436,14 +1436,13 @@ next_loop:
>  		rl_rec = pop_slab_cursor(rl_cur);
>  	}
>  
> -err:
> -	if (bt_cur)
> -		libxfs_btree_del_cursor(bt_cur, error ? XFS_BTREE_ERROR :
> -							XFS_BTREE_NOERROR);
> -	if (pag)
> -		libxfs_perag_put(pag);
> -	if (agbp)
> -		libxfs_buf_relse(agbp);
> +err_loop:
> +	libxfs_btree_del_cursor(bt_cur, error ?
> +				XFS_BTREE_ERROR : XFS_BTREE_NOERROR);
> +err_bt_cur:
> +	libxfs_buf_relse(agbp);
> +err_agf:
> +	libxfs_perag_put(pag);
>  	free_slab_cursor(&rl_cur);
>  }
>  
>