linux-kernel - Re: [PATCHv12 4/9] x86/boot/compressed: Handle unaccepted memory

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]

Date:   Fri, 19 May 2023 13:16:41 +0300
From:   "Kirill A. Shutemov" <kirill@...temov.name>
To:     "Kirill A. Shutemov" <kirill.shutemov@...ux.intel.com>
Cc:     Borislav Petkov <bp@...en8.de>, Andy Lutomirski <luto@...nel.org>,
        Dave Hansen <dave.hansen@...el.com>,
        Sean Christopherson <seanjc@...gle.com>,
        Andrew Morton <akpm@...ux-foundation.org>,
        Joerg Roedel <jroedel@...e.de>,
        Ard Biesheuvel <ardb@...nel.org>,
        Andi Kleen <ak@...ux.intel.com>,
        Kuppuswamy Sathyanarayanan 
        <sathyanarayanan.kuppuswamy@...ux.intel.com>,
        David Rientjes <rientjes@...gle.com>,
        Vlastimil Babka <vbabka@...e.cz>,
        Tom Lendacky <thomas.lendacky@....com>,
        Thomas Gleixner <tglx@...utronix.de>,
        Peter Zijlstra <peterz@...radead.org>,
        Paolo Bonzini <pbonzini@...hat.com>,
        Ingo Molnar <mingo@...hat.com>,
        Dario Faggioli <dfaggioli@...e.com>,
        Mike Rapoport <rppt@...nel.org>,
        David Hildenbrand <david@...hat.com>,
        Mel Gorman <mgorman@...hsingularity.net>,
        marcelo.cerri@...onical.com, tim.gardner@...onical.com,
        khalid.elmously@...onical.com, philip.cox@...onical.com,
        aarcange@...hat.com, peterx@...hat.com, x86@...nel.org,
        linux-mm@...ck.org, linux-coco@...ts.linux.dev,
        linux-efi@...r.kernel.org, linux-kernel@...r.kernel.org,
        Liam Merwick <liam.merwick@...cle.com>
Subject: Re: [PATCHv12 4/9] x86/boot/compressed: Handle unaccepted memory

On Fri, May 19, 2023 at 02:14:29AM +0300, Kirill A. Shutemov wrote:
> diff --git a/arch/x86/boot/compressed/mem.c b/arch/x86/boot/compressed/mem.c
> index 67594fcb11d9..87372b96d613 100644
> --- a/arch/x86/boot/compressed/mem.c
> +++ b/arch/x86/boot/compressed/mem.c
> @@ -1,9 +1,32 @@
>  // SPDX-License-Identifier: GPL-2.0-only
>  
>  #include "error.h"
> +#include "misc.h"
>  
>  void arch_accept_memory(phys_addr_t start, phys_addr_t end)
>  {
>  	/* Platform-specific memory-acceptance call goes here */
>  	error("Cannot accept memory");
>  }
> +
> +void init_unaccepted_memory(void)
> +{
> +	guid_t guid =  LINUX_EFI_UNACCEPTED_MEM_TABLE_GUID;
> +	struct efi_unaccepted_memory *unaccepted_table;
> +	unsigned long cfg_table_pa;
> +	unsigned int cfg_table_len;
> +	int ret;
> +
> +	ret = efi_get_conf_table(boot_params, &cfg_table_pa, &cfg_table_len);
> +	if (ret)
> +		error("EFI config table not found.");
> +
> +	unaccepted_table = (void *)efi_find_vendor_table(boot_params,
> +							 cfg_table_pa,
> +							 cfg_table_len,
> +							 guid);
> +	if (unaccepted_table->version != 1)
> +		error("Unknown version of unaccepted memory table\n");
> +
> +	set_unaccepted_table(unaccepted_table);
> +}

0-day reported boot failure outdise TDX guest with CONFIG_INTEL_TDX_GUEST=y.

The fixup:

diff --git a/arch/x86/boot/compressed/mem.c b/arch/x86/boot/compressed/mem.c
index 0108c97399a5..8df3d988ae69 100644
--- a/arch/x86/boot/compressed/mem.c
+++ b/arch/x86/boot/compressed/mem.c
@@ -56,6 +56,9 @@ void init_unaccepted_memory(void)
 							 cfg_table_pa,
 							 cfg_table_len,
 							 guid);
+	if (!unaccepted_table)
+		return;
+
 	if (unaccepted_table->version != 1)
 		error("Unknown version of unaccepted memory table\n");
 
-- 
  Kiryl Shutsemau / Kirill A. Shutemov