linux-kernel - Re: [PATCH v17 18/23] platform/x86: Intel SGX driver

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 for Android: free password hash cracker in your pocket

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

Message-ID: <20181217182319.GA13288@linux.intel.com>
Date:   Mon, 17 Dec 2018 20:23:19 +0200
From:   Jarkko Sakkinen <jarkko.sakkinen@...ux.intel.com>
To:     Sean Christopherson <sean.j.christopherson@...el.com>
Cc:     "Dr. Greg" <greg@...ellic.com>,
        Andy Lutomirski <luto@...capital.net>,
        Andy Lutomirski <luto@...nel.org>, X86 ML <x86@...nel.org>,
        Platform Driver <platform-driver-x86@...r.kernel.org>,
        linux-sgx@...r.kernel.org, Dave Hansen <dave.hansen@...el.com>,
        nhorman@...hat.com, npmccallum@...hat.com,
        "Ayoun, Serge" <serge.ayoun@...el.com>, shay.katz-zamir@...el.com,
        haitao.huang@...ux.intel.com,
        Andy Shevchenko <andriy.shevchenko@...ux.intel.com>,
        Thomas Gleixner <tglx@...utronix.de>,
        "Svahn, Kai" <kai.svahn@...el.com>, mark.shanahan@...el.com,
        Suresh Siddha <suresh.b.siddha@...el.com>,
        Ingo Molnar <mingo@...hat.com>, Borislav Petkov <bp@...en8.de>,
        "H. Peter Anvin" <hpa@...or.com>,
        Darren Hart <dvhart@...radead.org>,
        Andy Shevchenko <andy@...radead.org>,
        LKML <linux-kernel@...r.kernel.org>, jethro@...tanix.com
Subject: Re: [PATCH v17 18/23] platform/x86: Intel SGX driver

On Mon, Dec 17, 2018 at 10:09:57AM -0800, Sean Christopherson wrote:
> No, EREMOVE should never fail if the enclave is being released, i.e. all
> references to the enclave are gone.  And failure during sgx_encl_release()
> means we leaked an EPC page, which warrants a WARN.

Right that what I was suspecting as swapper should hold a ref to the
enclave while it is working on it. It is a programming error when this
happens.

Maybe change the boolean parameter to flags parameter have a flag to
use sgx_free_page()?

> That makes sense.

What do you think of Dave's proposal?

/Jarkko