Bugtraq: Re: patch for qpopper remote exploit bug

[mouse () RODENTS MONTREAL QC CA (der Mouse)]

> Today, snprintf and vsnprintf are required.  Without them, there's
> some code in the libraries which cannot be written safely.
> ie:
> gen/syslog.c:   prlen = vsnprintf(p, tbuf_left, fmt_cpy, ap);
Actually, stuff like this can be done just fine with what NetBSD (and
OpenBSD, presumably) calls funopen() - you don't actually {,v}snprintf.
Indeed, funopen() is a bit of a sledgehammer; all the rest of stdio
could be removed without losing any power (just convenience).

I actually prefer funopen() in most respects.  In particular, it allows
things like printing into mallocked storage without having to impose a
length limit (which naive use of snprintf and strdup does).

stdio has desperately needed something like funopen() for a long time.
It was so egregiously missing that I hacked it into the 4.3 stdio back
when I was working with 4.3...I called it fopenfxn() and the interface
was a bit different, but it was basically the same idea.

                                        der Mouse

                               mouse () rodents montreal qc ca
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