Re: [PATCH] x86/boot: add prototype for __fortify_panic()

From: Borislav Petkov
Date: Fri May 31 2024 - 15:08:49 EST


On Fri, May 31, 2024 at 09:53:28AM -0700, Kees Cook wrote:
> Under CONFIG_FORTIFY_SOURCE, the boot code *does* still uses
> fortify-string.h. It lets us both catch mistakes we can discover at
> compile and will catch egregious runtime mistakes, though the reporting
> is much simpler in the boot code.

>From where I'm standing, we're not catching anything in the
decompressor:

$ objdump -D arch/x86/boot/compressed/vmlinux | grep __fortify_panic
0000000001bec250 <__fortify_panic>:
$

Sure, in vmlinux proper (allmodconfig) we do:

objdump -D vmlinux | grep __fortify_panic | wc -l
1417

but not in the decompressor which is special anyway.

So we can just as well disable CONFIG_FORTIFY_SOURCE in the decompressor
and not do silly prototypes.

--
Regards/Gruss,
Boris.

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