From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751822AbeCLOaK (ORCPT ); Mon, 12 Mar 2018 10:30:10 -0400 Received: from a8-242.smtp-out.amazonses.com ([54.240.8.242]:60790 "EHLO a8-242.smtp-out.amazonses.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751255AbeCLOaH (ORCPT ); Mon, 12 Mar 2018 10:30:07 -0400 Subject: Re: Regression from efi: call get_event_log before ExitBootServices To: Ard Biesheuvel , Thiebaud Weksteen Cc: Hans de Goede , Javier Martinez Canillas , Jarkko Sakkinen , linux-efi@vger.kernel.org, linux-integrity@vger.kernel.org, tpmdd-devel@lists.sourceforge.net, Linux Kernel Mailing List References: <01000161fc0b4755-df0621f4-ab5d-479a-b425-adf98427a308-000000@email.amazonses.com> <0100016206a68850-bd5c96b3-f275-46ea-98b1-1317e02a5d6e-000000@email.amazonses.com> <29c1640a-cf19-ca19-7de9-96f202edfb5a@redhat.com> <010001620bafa06b-41525407-603e-40a9-ba11-6033b2f5dcc7-000000@email.amazonses.com> From: Jeremy Cline Message-ID: <010001621a9e5069-0b1a6328-97e4-4396-9438-b90f5b8c82a4-000000@email.amazonses.com> Date: Mon, 12 Mar 2018 14:30:05 +0000 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.6.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 8bit X-SES-Outgoing: 2018.03.12-54.240.8.242 Feedback-ID: 1.us-east-1.z18Isoc/FaoPOvCyJyi1mnTt8STwoRuibXVNoUcvG6g=:AmazonSES Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 03/12/2018 07:08 AM, Ard Biesheuvel wrote: > On 10 March 2018 at 10:45, Thiebaud Weksteen wrote: >> On Fri, Mar 9, 2018 at 5:54 PM Jeremy Cline wrote: >> >>> On Fri, Mar 09, 2018 at 10:43:50AM +0000, Thiebaud Weksteen wrote: >>>> Thanks a lot for trying out the patch! >>>> >>>> Please don't modify your install at this stage, I think we are hitting a >>>> firmware bug and that would be awesome if we can fix how we are >> handling it. >>>> So, if we reach that stage in the function it could either be that: >>>> * The allocation did not succeed, somehow, but the firmware still >> returned >>>> EFI_SUCCEED. >>>> * The size requested is incorrect (I'm thinking something like a 1G of >>>> log). This would be due to either a miscalculation of log_size >> (possible) >>>> or; the returned values of GetEventLog are not correct. >>>> I'm sending a patch to add checks for these. Could you please apply and >>>> retest? >>>> Again, thanks for helping debugging this. >> >>> No problem, thanks for the help :) >> >>> With the new patch: >> >>> Locating the TCG2Protocol >>> Calling GetEventLog on TCG2Protocol >>> Log returned >>> log_location is not empty >>> log_size != 0 >>> log_size < 1M >>> Allocating memory for storing the logs >>> Returned from memory allocation >>> Copying log to new location >> >>> And then it hangs. I added a couple more print statements: >> >>> diff --git a/drivers/firmware/efi/libstub/tpm.c >> b/drivers/firmware/efi/libstub/tpm.c >>> index ee3fac109078..1ab5638bc50e 100644 >>> --- a/drivers/firmware/efi/libstub/tpm.c >>> +++ b/drivers/firmware/efi/libstub/tpm.c >>> @@ -148,8 +148,11 @@ void >> efi_retrieve_tpm2_eventlog_1_2(efi_system_table_t *sys_table_arg) >>> efi_printk(sys_table_arg, "Copying log to new location\n"); >> >>> memset(log_tbl, 0, sizeof(*log_tbl) + log_size); >>> + efi_printk(sys_table_arg, "Successfully memset log_tbl to 0\n"); >>> log_tbl->size = log_size; >>> + efi_printk(sys_table_arg, "Set log_tbl->size\n"); >>> log_tbl->version = EFI_TCG2_EVENT_LOG_FORMAT_TCG_1_2; >>> + efi_printk(sys_table_arg, "Set log_tbl-version\n"); >>> memcpy(log_tbl->log, (void *) first_entry_addr, log_size); >> >>> efi_printk(sys_table_arg, "Installing the log into the >> configuration table\n"); >> >>> and it's hanging at "memset(log_tbl, 0, sizeof(*log_tbl) + log_size);" >> >> Thanks. Well, it looks like the memory that is supposedly allocated is not >> usable. I'm thinking this is a firmware bug. >> Ard, would you agree on this assumption? Thoughts on how to proceed? >> > > I am rather puzzled why the allocate_pool() should succeed and the > subsequent memset() should fail. This does not look like an issue that > is intimately related to TPM2 support, rather an issue in the firmware > that happens to get tickled after the change. > > Would you mind trying replacing EFI_LOADER_DATA with > EFI_BOOT_SERVICES_DATA in the allocate_pool() call? Replacing EFI_LOADER_DATA with EFI_BOOT_SERVICES_DATA still hangs at the memset() call. Regards, Jeremy