From: Jens Gustedt <jens.gustedt@inria.fr>
To: musl@lists.openwall.com
Subject: Re: New static analysis results
Date: Fri, 05 Sep 2014 22:50:52 +0200 [thread overview]
Message-ID: <1409950252.4856.83.camel@eris.loria.fr> (raw)
In-Reply-To: <20140905185338.GR23797@brightrain.aerifal.cx>
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Am Freitag, den 05.09.2014, 14:53 -0400 schrieb Rich Felker:
> See also asctime: it's even worse, specified to be UB, via potential
> buffer overflow, if the values are outside of the expected range.
>
> These functions really just should not be used for anything. Short of
> rolling your own, strftime is the only correct way to format time as a
> string.
the corresponding xxx_s functions from Annex K are a bit better, here.
> At some point it would be nice to make a big list of standard C
> functions that are utterly unusable due to UB on errors. Unusable due
> to lack of thread safety is another big area, too.
Annex K can basically be read as such a list (for C itself, not POSIX)
and gives replacements for them, I think.
Implementing these functions, using them with a constraint handler
that is set to ignore_handler_s, and checking for the return values of
the functions is a realistic alternative to all this UB stuff.
Jens
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next prev parent reply other threads:[~2014-09-05 20:50 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-09-04 16:45 Alexander Monakov
2014-09-04 17:13 ` Rich Felker
2014-09-05 18:02 ` Rich Felker
2014-09-05 18:39 ` Alexander Monakov
2014-09-05 18:53 ` Rich Felker
2014-09-05 20:50 ` Jens Gustedt [this message]
2014-09-05 21:23 ` Rich Felker
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