Automatic backtrace [Was: Re: NetAPP/Samba 3.0/plugs]

[Mike Gerdts]

On Wed, 2002-03-13 at 03:56, Andrew Bartlett wrote:
> Scott Gifford wrote:

> > Perhaps I'm missing something obvious, but why not just let Samba dump
> > core?...It's straightforward to provide a backtrace from a core file.
> 
> Where?  Under what uid?  Following what symlinks?  
> 
> Dumping core just has 'bad idea' written all over it.  Plus the people
> who know how to use gdb on a core file would already have a magic 'panic
> action' already setup.

Most systems will not dump core if real, effective, and saved (if it
exists) do not match.

Solaris 7 with the right patches and later allows you to get core dumps
in a defined location, even for setuid programs.  See coreadm(1) or
http://lists.samba.org/pipermail/samba-technical/2001-October/032047.html for details.  I have used this quit successfully with a variety of programs (including samba) to cause core dumps to be put in /var/cores, which I create as owned by root and mode 700.

I have seen mention of a similar patch for Linux mentioned.  I first saw
it mentioned at http://lwn.net/2002/0228/kernel.php3 , the kernel
mailing list message is http://lwn.net/2002/0228/a/coredump-name.php3 .

Mike