linux-kernel - Re: [PATCH v8 12/28] x86/insn-eval: Add utility functions to get segment selector

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]

Date:   Wed, 04 Oct 2017 09:47:50 -0700
From:   Ricardo Neri <ricardo.neri-calderon@...ux.intel.com>
To:     Borislav Petkov <bp@...e.de>
Cc:     Ingo Molnar <mingo@...hat.com>,
        Thomas Gleixner <tglx@...utronix.de>,
        "H. Peter Anvin" <hpa@...or.com>,
        Andy Lutomirski <luto@...nel.org>,
        Peter Zijlstra <peterz@...radead.org>,
        Andrew Morton <akpm@...ux-foundation.org>,
        Brian Gerst <brgerst@...il.com>,
        Chris Metcalf <cmetcalf@...lanox.com>,
        Dave Hansen <dave.hansen@...ux.intel.com>,
        Paolo Bonzini <pbonzini@...hat.com>,
        Masami Hiramatsu <mhiramat@...nel.org>,
        Huang Rui <ray.huang@....com>, Jiri Slaby <jslaby@...e.cz>,
        Jonathan Corbet <corbet@....net>,
        "Michael S. Tsirkin" <mst@...hat.com>,
        Paul Gortmaker <paul.gortmaker@...driver.com>,
        Vlastimil Babka <vbabka@...e.cz>,
        Chen Yucong <slaoub@...il.com>,
        "Ravi V. Shankar" <ravi.v.shankar@...el.com>,
        Shuah Khan <shuah@...nel.org>, linux-kernel@...r.kernel.org,
        x86@...nel.org, Adam Buchbinder <adam.buchbinder@...il.com>,
        Colin Ian King <colin.king@...onical.com>,
        Lorenzo Stoakes <lstoakes@...il.com>,
        Qiaowei Ren <qiaowei.ren@...el.com>,
        Arnaldo Carvalho de Melo <acme@...hat.com>,
        Adrian Hunter <adrian.hunter@...el.com>,
        Kees Cook <keescook@...omium.org>,
        Thomas Garnier <thgarnie@...gle.com>,
        Dmitry Vyukov <dvyukov@...gle.com>
Subject: Re: [PATCH v8 12/28] x86/insn-eval: Add utility functions to get
 segment selector

On Fri, 2017-09-29 at 13:56 +0200, Borislav Petkov wrote:
> On Thu, Sep 28, 2017 at 11:06:42PM -0700, Ricardo Neri wrote:
> > 
> > I agree. In fact, insn_get_seg_base() does not need insn at all. All it
> > needs is
> > a INAT_SEG_REG_* index. This would make things clear. UMIP (and callers that
> > need to copy_from_user code can do insn_get_seg_base(regs, INAT_SEG_REG_CS).
> > No
> > insn needed.
> Yap.
> 
> > 
> > In fact, it is only the insn_get_addr_ref_xx() family of functions that does
> I think you mean get_addr_ref_xx() here.

Yes.

> 
> > 
> > Do you think the pseudocode above addresses your concerns?
> > 
> > *insn_get_seg_base() will take a INAT_SEG_REG_* index
> > *insn_get_ref_xx() receives an initialized insn that can check for NULL
> > value.
> > *a reworked resolve_seg_reg_idx will clearly check if it can use segment
> > override prefixes and obtain them. If not, it will use default values.
> Makes sense, but send me the final version to take a look at it too.

I just sent a v9 with all these changes as they impacted several patches in the
series.

Thanks and BR,
Ricardo