[Xastir] Fwd: Canadian Call Sign lookup on Xastir-Ubuntu 10.04 Live CD

[James Cameron]

On Tue, Jul 20, 2010 at 12:20:44AM -0500, Jeremy Utley wrote:
> I don't think curl is the problem.  That's showing up in the memory
> map part of the output, meaning the curl library is loaded into
> memory, which you would expect.  The backtrace:
> 
> ======= Backtrace: =========
> /lib/tls/i686/cmov/libc.so.6(__fortify_fail+0x50)[0xfa3390]
> /lib/tls/i686/cmov/libc.so.6(+0xe12ca)[0xfa22ca]
> /lib/tls/i686/cmov/libc.so.6(__fgets_chk+0x129)[0xfa25e9]
> xastir[0x8153328]
> xastir[0x80bfddd]
> /usr/lib/libXt.so.6(XtCallCallbackList+0xb1)[0xbee4e1]

This looks like xastir is calling fgets and libc doesn't like the
parameters, or the stack got smashed.

> leads me to believe the problem is actually something in Xastir or the
> Motif libraries trigger up in the glibc code - most likely having to
> do with buffer overflow fortification.

Agreed.

> Unfortunately, since all the
> system libraries have no debug symbols in them, it's probably going to
> be hard to trace out where in the code the problem is.

You should be able to reinstall certain system libraries ... like
libc6-dbg.  May give you more symbolic detail, but on the other hand
this stack traceback looks like it is program generated ... any chance
of running xastir in gdb to get more detail?

But if it is a smashed stack, it is rare to find the cause merely by
adding symbols.  By the time the trace you showed us happened, the stack
was already damaged.  Running within valgrind may help though, since
valgrind will catch the point the damage was made.

> Looks like even the Xastir binary has been stripped of debugging
> symbols - Curt - does Xastir's make install strip the binary by
> default? 

Curt's reply triggered my re-read of your post.  Check the binary
carefully.  If it's a binary from a distro, or built using distro
techniques, then yes, it's likely to have been stripped.  When that
happens, and I need more data on a problem, I recompile without
stripping.

-- 
James Cameron
http://quozl.linux.org.au/