Re: 2.6.17-mm5 -- Busted toolchain? -- usr/klibc/exec_l.c:59: undefined reference to `__stack_chk_fail'

Miles Lane
2006-07-02T17:07:28Z

On 7/2/06, Arjan van de Ven <arjan@infradead.org> wrote:
>
> > https://wiki.ubuntu.com/GccSsp
> >
> > It appears that Ubuntu's Edgy Eft (the development tree) now contains
> > "Stack Smashing Protection" enabled by default. I found a web page
> > that states that -fno-stack-protector can be used to disable this
> > functionality. Interestingly, another web page stated that SSP has
> > been enabled in Redhat compilers for a long time and is now also
> > enabled in Debian SID. Perhaps -fno-stack-protector should be added
> > to the kernel build be default?
>
>
> gcc 4.1 and later have this feature yes.
> HOWEVER the gcc people were not stupid, they did not force this on
> people, they require you to put -fstack-protector on the commandline.
> Debian and RH/Fedora do this.
> If Ubuntu patched gcc rather than just putting it in the build
> environment... then you should switch to a less braindead distribution
> really ;)
> or at least ask them to fix this.

Well, from the web page referenced at the top of this message, you
can see that they are already aware of these issues:

Cons:
* It breaks current upstream kernel builds and potentially
other direct usages of gcc. Kernel is by far the most important use
case. Upstream should change the default options to build with
-fno-stack-protector by default.
* It is not conformant to upstream gcc behaviour.

You can reach the key people who are working on this for Ubuntu here:
Matt Zimmerman -- mdz at ubuntu dot com
Martin Pitt -- martin.pitt at ubuntu dot com

Perhaps you can convince them to back out this functional change?

Does this mean that you don't want to see these fno-stack-protector
patches go into Andrew's tree?

Miles