Re: regression: Bug 215601 - gcc segv at startup on ia64

[Kees Cook]

On Mon, Feb 21, 2022 at 10:57:01PM +0100, John Paul Adrian Glaubitz wrote:
> Hi Kees!
> 
> On 2/21/22 21:58, Kees Cook wrote:
> >> I have applied this patch on top of 038101e6b2cd5c55f888f85db42ea2ad3aecb4b6 and it doesn't
> >> fix the problem for me. Reverting 5f501d555653f8968011a1e65ebb121c8b43c144, however, fixes
> >> the problem.
> >>
> >> FWIW, this problem doesn't just affect GCC but systemd keeps segfaulting with this change as well.
> > 
> > Very weird! Can you attached either of those binaries to bugzilla (or a URL I can fetch it from)? I can try to figure out where it is going weird...
> 
> Here's the initrd of that particular machine:
> 
> > https://people.debian.org/~glaubitz/initrd.img-5.17.0-rc5+
> 
> You should be able to extract the binaries from this initrd image and the "mount" command,
> for example, should be one of the affected binaries.

In dmesg, do you see any of these reports?

                pr_info("%d (%s): Uhuuh, elf segment at %px requested but the memory is mapped already\n",
                        task_pid_nr(current), current->comm, (void *)addr);

I don't see anything out of order in the "mount" binary from the above
initrd. What does "readelf -lW" show for the GCC you're seeing failures
on?

-- 
Kees Cook