Re: [PATCH v2 1/2] udf: refactor VRS descriptor identification

[Jan Kara]

On Thu 11-07-19 20:15:21, Pali Rohár  wrote:
> On Thursday 11 July 2019 08:38:51 Steven J. Magnani wrote:
> > --- a/fs/udf/super.c	2019-07-10 18:57:41.192852154 -0500
> > +++ b/fs/udf/super.c	2019-07-10 20:47:50.438352500 -0500
> > @@ -685,16 +685,62 @@ out_unlock:
> >  	return error;
> >  }
> >  
> > -/* Check Volume Structure Descriptors (ECMA 167 2/9.1) */
> > -/* We also check any "CD-ROM Volume Descriptor Set" (ECMA 167 2/8.3.1) */
> > -static loff_t udf_check_vsd(struct super_block *sb)
> > +static int identify_vsd(const struct volStructDesc *vsd)
> > +{
> > +	int vsd_id = 0;
> > +
> > +	if (!strncmp(vsd->stdIdent, VSD_STD_ID_CD001, VSD_STD_ID_LEN)) {
> 
> Hi! You probably want to use memcmp() instead of strncmp().

There's no difference in functionality but I agree it makes more sense.
I'll modify the patch. Thanks for review!

								Honza

> 
> > +		switch (vsd->structType) {
> > +		case 0:
> > +			udf_debug("ISO9660 Boot Record found\n");
> > +			break;
> > +		case 1:
> > +			udf_debug("ISO9660 Primary Volume Descriptor found\n");
> > +			break;
> > +		case 2:
> > +			udf_debug("ISO9660 Supplementary Volume Descriptor found\n");
> > +			break;
> > +		case 3:
> > +			udf_debug("ISO9660 Volume Partition Descriptor found\n");
> > +			break;
> > +		case 255:
> > +			udf_debug("ISO9660 Volume Descriptor Set Terminator found\n");
> > +			break;
> > +		default:
> > +			udf_debug("ISO9660 VRS (%u) found\n", vsd->structType);
> > +			break;
> > +		}
> > +	} else if (!strncmp(vsd->stdIdent, VSD_STD_ID_BEA01, VSD_STD_ID_LEN))
> > +		vsd_id = 1;
> > +	else if (!strncmp(vsd->stdIdent, VSD_STD_ID_NSR02, VSD_STD_ID_LEN))
> > +		vsd_id = 2;
> > +	else if (!strncmp(vsd->stdIdent, VSD_STD_ID_NSR03, VSD_STD_ID_LEN))
> > +		vsd_id = 3;
> > +	else if (!strncmp(vsd->stdIdent, VSD_STD_ID_BOOT2, VSD_STD_ID_LEN))
> > +		; /* vsd_id = 0 */
> > +	else if (!strncmp(vsd->stdIdent, VSD_STD_ID_CDW02, VSD_STD_ID_LEN))
> > +		; /* vsd_id = 0 */
> > +	else {
> > +		/* TEA01 or invalid id : end of volume recognition area */
> > +		vsd_id = 255;
> > +	}
> > +
> > +	return vsd_id;
> > +}
> 
> -- 
> Pali Rohár
> pali.rohar@xxxxxxxxx


-- 
Jan Kara <jack@xxxxxxxx>
SUSE Labs, CR