From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:38070 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751348AbdGRPtt (ORCPT ); Tue, 18 Jul 2017 11:49:49 -0400 Date: Tue, 18 Jul 2017 17:49:42 +0200 From: Greg KH To: Josh Zimmerman Cc: Jarkko Sakkinen , Jason Gunthorpe , tpmdd-devel@lists.sourceforge.net, stable@vger.kernel.org Subject: Re: [PATCH v1 4/4] tpm: Issue a TPM2_Shutdown for TPM2 devices. Message-ID: <20170718154942.GD30882@kroah.com> References: <20170714195803.7035-1-joshz@google.com> <20170714195803.7035-5-joshz@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20170714195803.7035-5-joshz@google.com> Sender: stable-owner@vger.kernel.org List-ID: On Fri, Jul 14, 2017 at 12:58:03PM -0700, Josh Zimmerman wrote: > Backport of d1bd4a792d3961a04e6154118816b00167aad91a upstream. > > If a TPM2 loses power without a TPM2_Shutdown command being issued (a > "disorderly reboot"), it may lose some state that has yet to be > persisted to NVRam, and will increment the DA counter. After the DA > counter gets sufficiently large, the TPM will lock the user out. > > NOTE: This only changes behavior on TPM2 devices. Since TPM1 uses sysfs, > and sysfs relies on implicit locking on chip->ops, it is not safe to > allow this code to run in TPM1, or to add sysfs support to TPM2, until > that locking is made explicit. > --- > drivers/char/tpm/tpm-chip.c | 36 ++++++++++++++++++++++++++++++++++++ > drivers/char/tpm/tpm-sysfs.c | 7 +++++++ > 2 files changed, 43 insertions(+) > Again no signed-off-by :(