linux-kernel - Re: [PATCH] tpm: vtpm_proxy: Do not run tpm2

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: <20170525155059.GA5151@obsidianresearch.com>
Date:   Thu, 25 May 2017 09:50:59 -0600
From:   Jason Gunthorpe <jgunthorpe@...idianresearch.com>
To:     Stefan Berger <stefanb@...ux.vnet.ibm.com>
Cc:     jarkko.sakkinen@...ux.intel.com, tpmdd-devel@...ts.sourceforge.net,
        linux-security-module@...r.kernel.org, linux-kernel@...r.kernel.org
Subject: Re: [PATCH] tpm: vtpm_proxy: Do not run tpm2_shutdown

On Thu, May 25, 2017 at 09:12:36AM -0400, Stefan Berger wrote:
> The tpm2_shutdown does not work with the VTPM proxy driver since the
> function only gets called when the backend file descriptor is already
> closed and at this point no data can be sent anymore. A proper shutdown
> would have to be initated by a user space application, such as a container
> management stack, that sends the command via the character device before
> terminating the TPM emulator.
> 
> To avoid the tpm2_shutdown we introduce a TPM_CHIP_FLAG_NO_SHUTDOWN flag
> that only the VTPM proxy driver sets. This also avoids misleading kernel
> log messages.

This seems strange to me..

Why isn't ops null if the fd has gone away?

What is the call flow that hits this?

Jason