Re: [PATCH] bugfix for an underflow condition in usb storage & isd200.c

[Matthew Dharm <mdharm-scsi@one-eyed-alien.net>]

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On Mon, Feb 04, 2008 at 03:05:58PM -0500, Alan Stern wrote:
> On Sun, 3 Feb 2008, Matthew Dharm wrote:
> 
> I think the correct approach is to modify those routines so that they 
> will never overrun the s-g buffer (like Boaz has done), and _document_ 
> this behavior.  Then the callers can feel free to try and transfer as 
> much as they want, knowing that an overrun can't occur.  There won't 
> be any need for a WARN_ON or anything else.

Six of one and a half-dozen of the other.  All we're arguing over is the
definition of "correct behavior" here.  You want to change the API so that
overrun is acceptable and handled; I prefer calling it a Bad Thing(tm).

We both agree that the code shouldn't run off the end of the s-g list.

Since you've already committed to updating the patch, then we can do it
your way.  Just make sure it's very very clear in the comments.

Matt

-- 
Matthew Dharm                              Home: mdharm-usb@one-eyed-alien.net 
Maintainer, Linux USB Mass Storage Driver

E:  You run this ship with Windows?!  YOU IDIOT!
L:  Give me a break, it came bundled with the computer!
					-- ESR and Lan Solaris
User Friendly, 12/8/1998

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