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Re: QPOPPER problem.... ONE crude patch...
From: miquels () CISTRON NL (Miquel van Smoorenburg)
Date: Sun, 28 Jun 1998 00:18:22 +0200


In article <Pine.LNX.3.96.980627181545.1549A-100000 () hobbe tripnet se>,
Daniel Ryde <ryde () TRIPNET SE> wrote:
On Sat, 27 Jun 1998, Tom Brown wrote:

        vsnprintf(mp,sizeof(message)-(mp - message)-3,format,ap);

Dangerous, if the string is truncated it will skip the null termination,
then later the strcat might fail miserably (unless all arcitectures makes
for sure that, when allocated, the string is filled with null, which I
really doubt).

Unlike strncat, snprintf is supposed to add a trailing zero. If it
doesn't then your library implementation is wrong and you probably have
more things to worry about ..

Another note is the next lines of sprintf (architectures
that dont have vsprintf) that will have the same problem as vsprintf.
Change these to snprintf in a similar way, and add a null to the end.

I'll post a revised patch in a minute. For architectures without
vnsprintf() it just makes the buffer 4 times bigger, that's sufficient
(that's not a guess but a fact).

Mike.
--
 Miquel van Smoorenburg | Our vision is to speed up time,
    miquels () cistron nl  |   eventually eliminating it.



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