linux-kernel - Re: [PATCH 13/22] x86/srso: Fix vulnerability reporting for missing microcode

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] [day] [month] [year] [list]

Message-ID: <20230825072542.GFZOhXdgXpUidW51lC@fat_crate.local>
Date:   Fri, 25 Aug 2023 09:25:42 +0200
From:   Borislav Petkov <bp@...en8.de>
To:     Josh Poimboeuf <jpoimboe@...nel.org>
Cc:     x86@...nel.org, linux-kernel@...r.kernel.org,
        Peter Zijlstra <peterz@...radead.org>,
        Babu Moger <babu.moger@....com>,
        Paolo Bonzini <pbonzini@...hat.com>,
        Sean Christopherson <seanjc@...gle.com>, David.Kaplan@....com,
        Andrew Cooper <andrew.cooper3@...rix.com>,
        Nikolay Borisov <nik.borisov@...e.com>,
        gregkh@...uxfoundation.org, Thomas Gleixner <tglx@...utronix.de>
Subject: Re: [PATCH 13/22] x86/srso: Fix vulnerability reporting for missing
 microcode

On Sun, Aug 20, 2023 at 06:19:10PM -0700, Josh Poimboeuf wrote:
> + * 'Vulnerable: Safe RET, no microcode':
> +
> +   The "Safe Ret" mitigation (see below) has been applied to protect the

s/Ret/RET/

> @@ -2456,7 +2463,10 @@ static void __init srso_select_mitigation(void)
>  				setup_force_cpu_cap(X86_FEATURE_SRSO);
>  				x86_return_thunk = srso_return_thunk;
>  			}
> -			srso_mitigation = SRSO_MITIGATION_SAFE_RET;
> +			if (has_microcode)
> +				srso_mitigation = SRSO_MITIGATION_SAFE_RET;
> +			else
> +				srso_mitigation = SRSO_MITIGATION_SAFE_RET_UCODE_NEEDED;
>  		} else {
>  			pr_err("WARNING: kernel not compiled with CPU_SRSO.\n");
>  		}

You missed one "no microcode" here at out_print:

[    0.553950] Speculative Return Stack Overflow: Vulnerable: Safe RET, no microcode, no microcode

Thx.

-- 
Regards/Gruss,
    Boris.

https://people.kernel.org/tglx/notes-about-netiquette