From owner-freebsd-bugs@FreeBSD.ORG  Mon Feb  7 21:40:22 2005
Return-Path: <owner-freebsd-bugs@FreeBSD.ORG>
Delivered-To: freebsd-bugs@hub.freebsd.org
Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125])
	by hub.freebsd.org (Postfix) with ESMTP id F11BE16A4CE
	for <freebsd-bugs@hub.freebsd.org>;
	Mon,  7 Feb 2005 21:40:22 +0000 (GMT)
Received: from freefall.freebsd.org (freefall.freebsd.org [216.136.204.21])
	by mx1.FreeBSD.org (Postfix) with ESMTP id BE65E43D46
	for <freebsd-bugs@hub.freebsd.org>;
	Mon,  7 Feb 2005 21:40:22 +0000 (GMT)
	(envelope-from gnats@FreeBSD.org)
Received: from freefall.freebsd.org (gnats@localhost [127.0.0.1])
	by freefall.freebsd.org (8.13.1/8.13.1) with ESMTP id j17LeMHg040394
	for <freebsd-bugs@freefall.freebsd.org>; Mon, 7 Feb 2005 21:40:22 GMT
	(envelope-from gnats@freefall.freebsd.org)
Received: (from gnats@localhost)
	by freefall.freebsd.org (8.13.1/8.13.1/Submit) id j17LeMLL040393;
	Mon, 7 Feb 2005 21:40:22 GMT
	(envelope-from gnats)
Date: Mon, 7 Feb 2005 21:40:22 GMT
Message-Id: <200502072140.j17LeMLL040393@freefall.freebsd.org>
To: freebsd-bugs@FreeBSD.org
From: Andriy Gapon <avg@icyb.net.ua>
Subject: Re: kern/77234: corrupted data is read from UDF filesystem if read
 starts at non-aligned offset
X-BeenThere: freebsd-bugs@freebsd.org
X-Mailman-Version: 2.1.1
Precedence: list
Reply-To: Andriy Gapon <avg@icyb.net.ua>
List-Id: Bug reports <freebsd-bugs.freebsd.org>
List-Unsubscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-bugs>,
	<mailto:freebsd-bugs-request@freebsd.org?subject=unsubscribe>
List-Archive: <http://lists.freebsd.org/pipermail/freebsd-bugs>
List-Post: <mailto:freebsd-bugs@freebsd.org>
List-Help: <mailto:freebsd-bugs-request@freebsd.org?subject=help>
List-Subscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-bugs>,
	<mailto:freebsd-bugs-request@freebsd.org?subject=subscribe>
X-List-Received-Date: Mon, 07 Feb 2005 21:40:23 -0000

The following reply was made to PR kern/77234; it has been noted by GNATS.

From: Andriy Gapon <avg@icyb.net.ua>
To: FreeBSD-gnats-submit@FreeBSD.org, freebsd-bugs@FreeBSD.org
Cc:  
Subject: Re: kern/77234: corrupted data is read from UDF filesystem if read
 starts at non-aligned offset
Date: Mon, 7 Feb 2005 23:31:30 +0200 (EET)

 If meaning of max_size is interpreted as maximum number of contiguous 
 bytes that can be read starting from a given offset rather than starting 
 from a beginning of a calculated sector number then a patch could be like 
 the following. (Please note that currently max_size contains number of 
 bytes in an extent to which current offset belongs, which is total 
 nonsense since any code that calls udf_bmap_internal() has no notion of 
 extents)
 
 --- udf_vnops.c.orig	Mon Feb  7 22:59:34 2005
 +++ udf_vnops.c	Mon Feb  7 23:18:06 2005
 @@ -1107,19 +1107,21 @@
   		*size = max_size;
   	*size = min(*size, MAXBSIZE);
 
 -	if ((error = udf_readlblks(udfmp, sector, *size, bp))) {
 +	if ((error = udf_readlblks(udfmp, sector, *size + (offset & udfmp->bmask), bp))) {
   		printf("warning: udf_readlblks returned error %d\n", error);
   		return (error);
   	}
 
   	bp1 = *bp;
 -	*data = (uint8_t *)&bp1->b_data[offset % udfmp->bsize];
 +	*data = (uint8_t *)&bp1->b_data[offset & udfmp->bmask];
   	return (0);
   }
 
   /*
    * Translate a file offset into a logical block and then into a physical
    * block.
 + * max_size - maximum number of bytes that can be read starting from given
 + * offset, not beginning of calculated sector number
    */
   static int
   udf_bmap_internal(struct udf_node *node, off_t offset, daddr_t *sector, uint32_t *max_size)
 @@ -1172,7 +1174,7 @@
   		lsector = (offset  >> udfmp->bshift) +
   		    ((struct short_ad *)(icb))->pos;
 
 -		*max_size = GETICBLEN(short_ad, icb);
 +		*max_size = icblen - offset;
 
   		break;
   	case 1:
 @@ -1196,7 +1198,7 @@
   		lsector = (offset >> udfmp->bshift) +
   		    ((struct long_ad *)(icb))->loc.lb_num;
 
 -		*max_size = GETICBLEN(long_ad, icb);
 +		*max_size = icblen - offset;
 
   		break;
   	case 3: