Hi,
On Fri, Nov 15, 2024 at 08:41:34AM +0000, Ulrich Teichert wrote:
>
> Hi,
>
> I ran a lengthy git bisect yesterday and it's this commit on the stable
> kernel git
> which causes the issue:
>
> b0cde867b80a5e81fcbc0383e138f5845f2005ee is the first bad commit
> commit b0cde867b80a5e81fcbc0383e138f5845f2005ee
> Author: Kees Cook <keesc...@chromium.org>
> Date: Fri Feb 16 22:25:43 2024 -0800
> x86: Increase brk randomness entropy for 64-bit systems
> [ Upstream commit 44c76825d6eefee9eb7ce06c38e1a6632ac7eb7d ]
> In commit c1d171a00294 ("x86: randomize brk"), arch_randomize_brk() was
> defined to use a 32MB range (13 bits of entropy), but was never increased
> when moving to 64-bit. The default arch_randomize_brk() uses 32MB for
> 32-bit tasks, and 1GB (18 bits of entropy) for 64-bit tasks.
> Update x86_64 to match the entropy used by arm64 and other 64-bit
> architectures.
> Reported-by: y0un9n...@gmail.com
> Signed-off-by: Kees Cook <keesc...@chromium.org>
> Signed-off-by: Thomas Gleixner <t...@linutronix.de>
> Acked-by: Jiri Kosina <jkos...@suse.com>
> Closes:
> https://lore.kernel.org/linux-hardening/CA+2EKTVLvc8hDZc+2Yhwmus=dzoug5e4gv7aycbu0mpjtzz...@mail.gmail.com/
> Link:
> https://lore.kernel.org/r/20240217062545.1631668-1-keesc...@chromium.org
> Signed-off-by: Sasha Levin <sas...@kernel.org>
>
> When I revert it, I can run pbuilder for ARM64 builds all day and it never
> crashes.
Thanks for bisecting it, I think it makes now sense to bring this to
upstream as I see there is not commit in mainline with fixes tag on
the commit.
Can you report it upstream? Make sure to include as well the
regressions list. At least the above people touching the commit should
as well be included.
Regards,
Salvatore
