Re: [PATCH] udf: disallow RW mount without valid integrity descriptor

[Jan Kara]

On Mon 11-02-19 08:24:38, Steve Magnani wrote:
> Refuse to mount a volume read-write without a coherent Logical Volume
> Integrity Descriptor, because we can't generate truly unique IDs without 
> one.
> 
> This fixes a bug where all inodes created on a UDF filesystem following
> mount without a coherent LVID are assigned UID 0.
> 
> Signed-off-by: Steven J. Magnani <steve@xxxxxxxxxxxxxxx>

Thanks. Added to my tree.

								Honza

> ---
> --- a/fs/udf/super.c	2018-11-16 06:43:00.622344354 -0600
> +++ b/fs/udf/super.c	2019-02-11 08:08:00.478331631 -0600
> @@ -1474,6 +1474,17 @@ static int udf_load_logicalvol(struct su
>  	if (lvd->integritySeqExt.extLength)
>  		udf_load_logicalvolint(sb, leea_to_cpu(lvd->integritySeqExt));
>  	ret = 0;
> +
> +	if (!sbi->s_lvid_bh) {
> +		/* We can't generate UIDs without a valid LVID */
> +		if (sb_rdonly(sb))
> +			UDF_SET_FLAG(sb, UDF_FLAG_RW_INCOMPAT);
> +		else {
> +			udf_warn(sb, "Damaged or missing LVID, forcing "
> +				     "readonly mount\n");
> +			ret = -EACCES;
> +		}
> +	}
>  out_bh:
>  	brelse(bh);
>  	return ret;
> 
-- 
Jan Kara <jack@xxxxxxxx>
SUSE Labs, CR