The following reply was made to PR kern/32193; it has been noted by GNATS.

From: Chuck Silvers <chuq@chuq.com>
To: gnats-bugs@netbsd.org
Cc: kern-bug-people@netbsd.org, gnats-admin@netbsd.org,
	netbsd-bugs@netbsd.org
Subject: Re: kern/32193: vop_strategy gets broken struct buf's passed by genfs/bread, possible memory leakage
Date: Wed, 30 Nov 2005 21:31:47 -0800

 On Tue, Nov 29, 2005 at 11:29:00PM +0000, reinoud@netbsd.org wrote:
 > VOP_STRATEGY buffers
 > --------------------
 > vop_strategy buffers are passed from genfs in 
 > sys/miscfs/genfs/genfs_vnops.c:836's VOP_TRATEGY call and created at either 
 > line 673 or at line 810 of the same file. In the buffer `mbp' created at 
 > line 673, all seems OK but at the buffer `bp' created at line 810, 
 > bp->b_bufsize is not initialised and thus ZERO!!!! quite a violation.
 
 the b_bufsize is for the caching usage of struct buf,
 not the I/O descriptor usage.  device drivers should not look at it
 (and neither should file systems for that matter).
 
 
 > bread buffers
 > -------------
 > vop_strategy buffers are passed from bread() in sys/kern/vfs_bio.c's 
 > bio_doread() at line 597's VOP_STRATEGY().
 > 
 > These buffers are claimed/looked up just before in line 577's getblk(). 
 > When passed to UDF's vop_strategy() bp->b_resid is undefined though mostly 
 > ZERO. Also not according to the struct buf's specs wich would suggest the 
 > number of bytes to be read/written in/from the buffer to be bp->b_resid.
 
 b_resid is a return value, it is initialized by the device driver
 before it calls biodone().
 
 
 > Other filingsystems
 > ----------
 > Filingsystems seem to cope with it by passing the buffers directly to the 
 > device layer that aparently ignores most of the buf contents and only 
 > reacts to bp->b_count.
 > 
 > Filingsystems that do care about the buffer contents are also only looking 
 > at bp->b_count.
 
 right, this is by design.
 
 
 as other people have also said, none of the behaviours you've described
 are bugs.
 
 -Chuck