Re: [PATCH v2 5/5] x86/head/64: Disable stack protection for head$(BITS).o

From: Arvind Sankar
Date: Fri Oct 16 2020 - 10:16:31 EST


On Fri, Oct 16, 2020 at 03:15:45PM +0200, Borislav Petkov wrote:
> On Fri, Oct 16, 2020 at 08:43:01AM -0400, Arvind Sankar wrote:
> > You need STACKPROTECTOR_STRONG -- I was testing with defconfig and the
> > option is enabled by default.
>
> And you need to write those things in the commit messages.
>
> Please, for the future, always make sure that all required ingredients
> for triggering a bug are documented in the commit message, before
> sending a fix. Jörg and I were both scratching heads on how you're
> reproducing this.
>
> Thx.
>

Sorry about that. This config option I didn't notice before since I
hadn't explicitly enabled the option, but I should have been more clear
about how I reproduced. I actually came across this from the other end,
was looking at the disassembly, saw the stack check call, and then spent
a while debugging why it did _not_ just always crash.

Thanks.