linux-kernel - Re: [PATCH 1/2] x86/boot/compressed/64: Remove .bss/.pgtable from bzImage

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20200405231845.GA3095309@rani.riverdale.lan>
Date:   Sun, 5 Apr 2020 19:18:45 -0400
From:   Arvind Sankar <nivedita@...m.mit.edu>
To:     Sergey Shatunov <me@...k.pw>
Cc:     nivedita@...m.mit.edu, bp@...en8.de, hpa@...or.com,
        linux-kernel@...r.kernel.org, mingo@...hat.com, tglx@...utronix.de,
        x86@...nel.org, linux-efi@...r.kernel.org
Subject: Re: [PATCH 1/2] x86/boot/compressed/64: Remove .bss/.pgtable from
 bzImage

On Sun, Apr 05, 2020 at 10:42:46PM +0700, Sergey Shatunov wrote:
> This patch causes some strange things happens with my laptop.
> 
> Cold boot crashed in some early initilization logic with message 'Failed to execute /esp/.../linux.efi: Buffer Too Small'.
> After couple reboots into firmware setup (bios) or hot reboot from other working kernel (without that commit) helps it to boot.
> During bisecting couple times I saw different message: 'exit_efi() failed; efi_main() failed', but above tricks helps it too.
> So bisect points to that commit and I tried to compile kernel with that commit reverted and it works flawlessly.
> 
> Some notes about my setup:
> Kernel tree I used: Torvalds git (which recently pulls that commit).
> Kernel itself with initrd and cmdline packed into systemd-boot stub (probably here can be issues too, not sure).
> Secure boot enabled with custom keyring.
> 
> I can provide more info or change my setup (for example get rid of systemd-boot stub) if needed for sure.

I'm not familiar with systemd-boot: when you say systemd-boot stub, is
that something different from the kernel's EFI_STUB option? Or is it
just a kernel with EFI_STUB enabled and with builtin initramfs + builtin
cmdline? If it is different, can you point me to the tool that creates
it?

The first error message you mention should be from systemd-boot after
the kernel exits with an EFI_BUFFER_TOO_SMALL error status. The second
one -- is that 'exit_boot() failed' rather than 'exit_efi() failed'? I
can't find the latter string in the tree.

Can you also specify a commit tag that is broken + works with this patch
reverted, just to make sure we're looking at the same code?

Thanks

Cc linux-efi.