From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jeremy Cline Subject: Re: Regression from efi: call get_event_log before ExitBootServices Date: Mon, 12 Mar 2018 18:33:13 +0000 Message-ID: <010001621b7ce5a3-b80c55b8-be68-4b44-ab52-4949e8ddb8d0-000000@email.amazonses.com> 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> <010001621a9e5069-0b1a6328-97e4-4396-9438-b90f5b8c82a4-000000@email.amazonses.com> <010001621b287e42-58955302-cc14-4212-b7b0-e6e358633dab-000000@email.amazonses.com> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: Content-Language: en-US Sender: linux-kernel-owner@vger.kernel.org To: Thiebaud Weksteen Cc: hdegoede@redhat.com, Ard Biesheuvel , Javier Martinez Canillas , Jarkko Sakkinen , linux-efi@vger.kernel.org, linux-integrity@vger.kernel.org, tpmdd-devel@lists.sourceforge.net, linux-kernel@vger.kernel.org List-Id: tpmdd-devel@lists.sourceforge.net On 03/12/2018 02:29 PM, Thiebaud Weksteen wrote: > On Mon, Mar 12, 2018 at 6:30 PM Ard Biesheuvel > wrote: > >> On 12 March 2018 at 17:01, Jeremy Cline wrote: >>> On 03/12/2018 10:56 AM, Ard Biesheuvel wrote: >>>> On 12 March 2018 at 14:30, Jeremy Cline wrote: >>>>> 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. >>>>> >>>> >>>> Could you try the following please? (attached as well in case gmail > mangles it) >>>> >>>> diff --git a/drivers/firmware/efi/libstub/tpm.c >>>> b/drivers/firmware/efi/libstub/tpm.c >>>> index 2298560cea72..30d960a344b7 100644 >>>> --- a/drivers/firmware/efi/libstub/tpm.c >>>> +++ b/drivers/firmware/efi/libstub/tpm.c >>>> @@ -70,6 +70,8 @@ void >>>> efi_retrieve_tpm2_eventlog_1_2(efi_system_table_t *sys_table_arg) >>>> size_t log_size, last_entry_size; >>>> efi_bool_t truncated; >>>> void *tcg2_protocol; >>>> + unsigned long num_pages; >>>> + efi_physical_addr_t log_tbl_alloc; >>>> >>>> status = efi_call_early(locate_protocol, &tcg2_guid, NULL, >>>> &tcg2_protocol); >>>> @@ -104,9 +106,12 @@ void >>>> efi_retrieve_tpm2_eventlog_1_2(efi_system_table_t *sys_table_arg) >>>> } >>>> >>>> /* Allocate space for the logs and copy them. */ >>>> - status = efi_call_early(allocate_pool, EFI_LOADER_DATA, >>>> - sizeof(*log_tbl) + log_size, >>>> - (void **) &log_tbl); >>>> + num_pages = DIV_ROUND_UP(sizeof(*log_tbl) + log_size, > EFI_PAGE_SIZE); >>>> + status = efi_call_early(allocate_pages, >>>> + EFI_ALLOCATE_ANY_PAGES, >>>> + EFI_LOADER_DATA, >>>> + num_pages, >>>> + &log_tbl_alloc); >>>> >>>> if (status != EFI_SUCCESS) { >>>> efi_printk(sys_table_arg, >>>> @@ -114,6 +119,7 @@ void >>>> efi_retrieve_tpm2_eventlog_1_2(efi_system_table_t *sys_table_arg) >>>> return; >>>> } >>>> >>>> + log_tbl = (struct linux_efi_tpm_eventlog *)(unsigned > long)log_tbl_alloc; >>>> memset(log_tbl, 0, sizeof(*log_tbl) + log_size); >>>> log_tbl->size = log_size; >>>> log_tbl->version = EFI_TCG2_EVENT_LOG_FORMAT_TCG_1_2; >>>> @@ -126,7 +132,7 @@ void >>>> efi_retrieve_tpm2_eventlog_1_2(efi_system_table_t *sys_table_arg) >>>> return; >>>> >>>> err_free: >>>> - efi_call_early(free_pool, log_tbl); >>>> + efi_call_early(free_pages, log_tbl_alloc, num_pages); >>>> } >>>> >>>> void efi_retrieve_tpm2_eventlog(efi_system_table_t *sys_table_arg) >>>> >>> >>> Hi Ard, >>> >>> When I apply this, it starts hanging at >>> >>> status = efi_call_proto(efi_tcg2_protocol, get_event_log, tcg2_protocol, >>> EFI_TCG2_EVENT_LOG_FORMAT_TCG_1_2, >>> &log_location, &log_last_entry, &truncated); >>> >>> rather than at the memset() call. >>> > >> That is *very* surprising, given that the change only affects code >> that executes after that. > >> I understand how annoying this is for you, and I think we should try >> to fix this, but reverting the patches outright isn't the solution >> either. > >> Which UEFI vendor and version does your system report? > > You should be able to find this info using the "ver" command in the UEFI > shell. > The UEFI vendor is Insyde (see first message). > Ah, thanks! EFI Specification Revision : 2.40 EFI Vendor : INSYDE Corp. EFI Revision : 21573.83 Regards, Jeremy