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

From: Kees Cook
Date: Mon Feb 28 2022 - 15:41:56 EST


On Mon, Feb 28, 2022 at 11:46:13AM +0100, Magnus Groß wrote:
> > When the kernel tries to map these with a combined allocation, it asks
> > for a giant mmap of the file, but the file is, of course, not at all
> > that large, and the mapping is rejected.
>
> > So... I'm trying to think about how best to deal with this. If I or
> > anyone else can't think of an elegant solution, I'll send a revert for
> > the offending patch next week.
>
> Shouldn't we just be able to patch total_mapping_size() again to instead
> sum up all p_memsz fields, instead of comparing minimum and maximum
> p_vaddr?

I don't think so, and I need to have a "minimal change" to fix this so
it's more obviously correct.

And, apologies, I failed to Cc you on this patch:
https://lore.kernel.org/linux-hardening/20220228194613.1149432-1-keescook@xxxxxxxxxxxx/

--
Kees Cook