wctomb crashes for negative WC for glibc shipped with RH7.1

[Vlad Harchev]

 Hi, 

 Sorry, I can't provide you with exact version number of glibc (I'm writing
from other place, not from where I got a bug) - but it's about glibc shipped
with non-upgraded (vanilla) RedHat 7.1 on x86.

 Bugreport itself:

 wctomb crashes when it's argument is negative (a lot of lame code don't
convert (char) to (unsigned char) before casting it to wchar_t).

 Backtrace of the crash (sorry for extrac quoting - it's from my other
letter):
> > (no debugging symbols found)...0x40864519 in __wait4 ()
> >    from /lib/i686/libc.so.6
> > #0  0x40864519 in __wait4 () from /lib/i686/libc.so.6
> > #1  0x408d49e4 in __DTOR_END__ () from /lib/i686/libc.so.6
> > #2  0x404a3262 in gnome_segv_handle (signum=11) at gnome-init.c:659
> > #3  <signal handler called>
> > #4  0x40956f73 in gconv () from /usr/lib/gconv/KOI8-R.so
> > #5  0x4083688a in __wcrtomb (s=0xbffff590 "\210\002", wc=-15,
> > ps=0x408d8aa0)
> >     at wcrtomb.c:85
> > #6  0x407da8cf in wctomb (s=0xbffff590 "\210\002", wchar=-15) at
> > wctomb.c:53

 Locale: ru_RU.KOI8-R

 I think it will crash under any locale.

 Thanks for developing glibc!

 Best regards,
  -Vlad