lists.openwall.net   lists  /  announce  owl-users  owl-dev  john-users  john-dev  passwdqc-users  yescrypt  popa3d-users  /  oss-security  kernel-hardening  musl  sabotage  tlsify  passwords  /  crypt-dev  xvendor  /  Bugtraq  Full-Disclosure  linux-kernel  linux-netdev  linux-ext4  linux-hardening  linux-cve-announce  PHC 
Open Source and information security mailing list archives
 
Hash Suite: Windows password security audit tool. GUI, reports in PDF.
[<prev] [next>] [<thread-prev] [day] [month] [year] [list]
Message-ID: <alpine.LFD.0.999.0709201946130.17093@enigma.security.iitk.ac.in>
Date:	Thu, 20 Sep 2007 19:54:31 +0530 (IST)
From:	Satyam Sharma <satyam@...radead.org>
To:	"Maciej W. Rozycki" <macro@...ux-mips.org>
cc:	Andrew Morton <akpm@...ux-foundation.org>,
	Antonino Daplas <adaplas@....net>,
	linux-fbdev-devel@...ts.sourceforge.net, linux-mips@...ux-mips.org,
	linux-kernel@...r.kernel.org
Subject: Re: [PATCH] drivers/video/pmag-ba-fb.c: Improve diagnostics



On Thu, 20 Sep 2007, Maciej W. Rozycki wrote:
> 
>  Perhaps preinitialising to an error value such as -EINVAL would be of
> more sense.  This way any error paths lacking initialisation are still
> reported as errors, even though the classification might be wrong.

Eeee ... at least I wouldn't prefer that. Why not simply use the
"int x = x;" trick (which is what uninitialized_var() does) -- it shuts
up the warning, and does *nothing* else. The bug will not be hidden, if
there's bad misbehaviour happening due to the bug, it will continue to
happen that way -- thus bringing our attention to it. Pre-initializing
to -EINVAL (or whatever) has the problem that when the bug actually
triggers, something unrelated might happen higher up the callchain, and
we'd be scratching our heads in a "why are we getting a -EINVAL here?"
kind of way ... worse still, we might think that this was _really_ an
EINVAL and go about debugging it ...

Plus, pre-initializing to -EINVAL (or even 0) will waste some bytes in
kernel text size, but no such overhead with uninitialized_var() :-)


Satyam
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Powered by blists - more mailing lists

Powered by Openwall GNU/*/Linux Powered by OpenVZ