linux-kernel - Re: [PATCH 3.16 56/76] x86/syscall: Sanitize syscall table de-references under speculation

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: <2a1d3a0f-6227-39c6-0ed9-a07c22424d67@suse.cz>
Date:   Mon, 12 Mar 2018 08:32:12 +0100
From:   Jiri Slaby <jslaby@...e.cz>
To:     Ben Hutchings <ben@...adent.org.uk>, linux-kernel@...r.kernel.org,
        stable@...r.kernel.org
Cc:     akpm@...ux-foundation.org,
        Jinpu Wang <jinpu.wang@...fitbricks.com>,
        kernel-hardening@...ts.openwall.com,
        Andy Lutomirski <luto@...nel.org>,
        Linus Torvalds <torvalds@...ux-foundation.org>,
        Jan Beulich <JBeulich@...e.com>, alan@...ux.intel.com,
        Thomas Gleixner <tglx@...utronix.de>,
        Dan Williams <dan.j.williams@...el.com>,
        gregkh@...uxfoundation.org, linux-arch@...r.kernel.org
Subject: Re: [PATCH 3.16 56/76] x86/syscall: Sanitize syscall table
 de-references under speculation

On 03/12/2018, 04:06 AM, Ben Hutchings wrote:
> In 3.16 the x86_32 syscall table lookup is also written in assembly.
> So I've taken Jiri's version and added similar masking in entry_32.S,
> using edx as the temporary.  edx is clobbered by SAVE_REGS and seems
> to be free at this point.

I don't know the state in 3.16, but in 3.12, I had to fix the 32bit
entry on 64bit in arch/x86/ia32/ia32entry.S (ia32_sysenter_target &
others) too.

thanks,
-- 
js
suse labs