kernel/drivers/firmware/efi/libstub/tpm.c, branch linux-6.18.y

libstub,tpm: do not ignore failure case when reading final event log

2024-10-15T18:27:30Z

Current code fails to check for an error case when reading events from final event log to calculate offsets. Check the error case, and break early because all subsequent calls will also fail. Signed-off-by: Gregory Price Signed-off-by: Ard Biesheuvel

tpm: fix unsigned/signed mismatch errors related to __calc_tpm2_event_size

2024-10-15T18:27:29Z

__calc_tpm2_event_size returns 0 or a positive length, but return values are often interpreted as ints. Convert everything over to u32 to avoid signed/unsigned logic errors. Signed-off-by: Gregory Price Signed-off-by: Ard Biesheuvel

efistub/tpm: Use ACPI reclaim memory for event log to avoid corruption

2024-09-13T06:53:03Z

The TPM event log table is a Linux specific construct, where the data produced by the GetEventLog() boot service is cached in memory, and passed on to the OS using an EFI configuration table. The use of EFI_LOADER_DATA here results in the region being left unreserved in the E820 memory map constructed by the EFI stub, and this is the memory description that is passed on to the incoming kernel by kexec, which is therefore unaware that the region should be reserved. Even though the utility of the TPM2 event log after a kexec is questionable, any corruption might send the parsing code off into the weeds and crash the kernel. So let's use EFI_ACPI_RECLAIM_MEMORY instead, which is always treated as reserved by the E820 conversion logic. Cc: Reported-by: Breno Leitao Tested-by: Usama Arif Reviewed-by: Ilias Apalodimas Signed-off-by: Ard Biesheuvel

efi/libstub: Add get_event_log() support for CC platforms

2024-03-09T10:37:17Z

To allow event log info access after boot, EFI boot stub extracts the event log information and installs it in an EFI configuration table. Currently, EFI boot stub only supports installation of event log only for TPM 1.2 and TPM 2.0 protocols. Extend the same support for CC protocol. Since CC platform also uses TCG2 format, reuse TPM2 support code as much as possible. Link: https://uefi.org/specs/UEFI/2.10/38_Confidential_Computing.html#efi-cc-measurement-protocol [1] Signed-off-by: Kuppuswamy Sathyanarayanan Link: https://lkml.kernel.org/r/0229a87e-fb19-4dad-99fc-4afd7ed4099a%40collabora.com [ardb: Split out final events table handling to avoid version confusion] Signed-off-by: Ard Biesheuvel

efi/tpm: Use symbolic GUID name from spec for final events table

2024-03-09T10:36:56Z

The LINUX_EFI_ GUID identifiers are only intended to be used to refer to GUIDs that are part of the Linux implementation, and are not considered external ABI. (Famous last words). GUIDs that already have a symbolic name in the spec should use that name, to avoid confusion between firmware components. So use the official name EFI_TCG2_FINAL_EVENTS_TABLE_GUID for the TCG2 'final events' configuration table. Reviewed-by: Kuppuswamy Sathyanarayanan Reviewed-by: Ilias Apalodimas Signed-off-by: Ard Biesheuvel

Merge tag 'efi-changes-for-v5.8' of git://git.kernel.org/pub/scm/linux/kernel/git/efi/efi into efi/core

2020-05-25T13:11:14Z

More EFI changes for v5.8: - Rename pr_efi/pr_efi_err to efi_info/efi_err, and use them consistently - Simplify and unify initrd loading - Parse the builtin command line on x86 (if provided) - Implement printk() support, including support for wide character strings - Some fixes for issues introduced by the first batch of v5.8 changes - Fix a missing prototypes warning - Simplify GDT handling in early mixed mode thunking code - Some other minor fixes and cleanups Conflicts: drivers/firmware/efi/libstub/efistub.h Signed-off-by: Ingo Molnar

tpm: check event log version before reading final events

2020-05-17T09:46:50Z

This fixes the boot issues since 5.3 on several Dell models when the TPM is enabled. Depending on the exact grub binary, booting the kernel would freeze early, or just report an error parsing the final events log. We get an event log in the SHA-1 format, which doesn't have a tcg_efi_specid_event_head in the first event, and there is a final events table which doesn't match the crypto agile format. __calc_tpm2_event_size reads bad "count" and "efispecid->num_algs", and either fails, or loops long enough for the machine to be appear frozen. So we now only parse the final events table, which is per the spec always supposed to be in the crypto agile format, when we got a event log in this format. Fixes: c46f3405692de ("tpm: Reserve the TPM final events table") Fixes: 166a2809d65b2 ("tpm: Don't duplicate events from the final event log in the TCG2 log") Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=1779611 Signed-off-by: Loïc Yhuel Link: https://lore.kernel.org/r/20200512040113.277768-1-loic.yhuel@gmail.com Reviewed-by: Javier Martinez Canillas Reviewed-by: Jerry Snitselaar Reviewed-by: Matthew Garrett [ardb: warn when final events table is missing or in the wrong format] Signed-off-by: Ard Biesheuvel

efi/tpm: Use efi_err for error messages

2020-05-01T07:40:02Z

Use efi_err instead of bare efi_printk for error messages. Signed-off-by: Arvind Sankar Link: https://lore.kernel.org/r/20200430182843.2510180-7-nivedita@alum.mit.edu Signed-off-by: Ard Biesheuvel

efi/libstub: Rename efi_call_early/_runtime macros to be more intuitive

2019-12-25T09:49:25Z

The macros efi_call_early and efi_call_runtime are used to call EFI boot services and runtime services, respectively. However, the naming is confusing, given that the early vs runtime distinction may suggest that these are used for calling the same set of services either early or late (== at runtime), while in reality, the sets of services they can be used with are completely disjoint, and efi_call_runtime is also only usable in 'early' code. So do a global sweep to replace all occurrences with efi_bs_call or efi_rt_call, respectively, where BS and RT match the idiom used by the UEFI spec to refer to boot time or runtime services. While at it, use 'func' as the macro parameter name for the function pointers, which is less likely to collide and cause weird build errors. Signed-off-by: Ard Biesheuvel Cc: Arvind Sankar Cc: Borislav Petkov Cc: James Morse Cc: Matt Fleming Cc: Thomas Gleixner Cc: linux-efi@vger.kernel.org Link: https://lkml.kernel.org/r/20191224151025.32482-24-ardb@kernel.org Signed-off-by: Ingo Molnar

efi/libstub: Drop protocol argument from efi_call_proto() macro

2019-12-25T09:49:24Z

After refactoring the mixed mode support code, efi_call_proto() no longer uses its protocol argument in any of its implementation, so let's remove it altogether. Signed-off-by: Ard Biesheuvel Cc: Arvind Sankar Cc: Borislav Petkov Cc: James Morse Cc: Matt Fleming Cc: Thomas Gleixner Cc: linux-efi@vger.kernel.org Link: https://lkml.kernel.org/r/20191224151025.32482-22-ardb@kernel.org Signed-off-by: Ingo Molnar