On Fri, Nov 13, 2015 at 10:30:32PM +0100, Joerg Jung wrote:
> Hi,
> 
> please find attached a port for the new suckless presentation tool sent.
> 
> OK to import?

hmm this code is of low quality for a tool released in 2015.

http://marc.infœ?t=144772469400002&r=1&w=2

As part of the xorg security team I looked at this to see of libXft is
responsible. I found that

sent /etc/passwd

will crash because 71 lines (on my machine) don't fit in a single
slide and the code that looks for a small enough font is buggy. It
uses an unsigned 'j' variable in a loop that says (getfontsize()
sent.c:321) :

     for (j = NUMFONTSCALES - 1; j >= 0; j--) {

so this will happily lead to huge j values, later used as indexes in
an array...

Even with that fixed, the same getfontsize() function won't be able to
handle the lack of an appropriate font and reference font[-1] with joy
and fireworks.

Later in the oss-sec thread someone noticed that 'sent empty' with
empty beeing a 0-length file will also produce a memory access
error. Indeed with malloc.conf -> J it happily dereferences a
0xd0d0d0d0d0d0d0 pointer since there is not such input as line[0] if
the file is empty.

I looked at this to check if there are bugs in Xft, not as as
potential user of misc/sent. So I won't bother trying to fix it,
sorry.

> 
> Regards,
> Joerg
> 
> 
> $ cat pkg/DESCR
> 
> Simple plaintext presentation tool.
> 
> sent does not need latex, libreoffice or any other fancy file format, it uses
> plaintext files and png images. Currently every paragraph represents a slide 
> in
> the presentation. Especially for presentations using the Takahashi method this
> is very nice and allows you to write down the presentation for a quick 
> lightning
> talk within a few minutes.
> 
> The presentation is displayed in a simple X11 window colored black on white 
> for
> maximum contrast even if the sun shines directly onto the projected image. The
> content of each slide is automatically scaled to fit the window so you don't
> have to worry about alignment. Instead you can really concentrate on the
> content.



-- 
Matthieu Herrb

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