From 6fb9367a15d1a126d222d738b2702c7958594a5f Mon Sep 17 00:00:00 2001 From: Lukas Wunner Date: Wed, 2 Oct 2019 18:58:58 +0200 Subject: [PATCH 1/8] efi/cper: Fix endianness of PCIe class code The CPER parser assumes that the class code is big endian, but at least on this edk2-derived Intel Purley platform it's little endian: efi: EFI v2.50 by EDK II BIOS ID:PLYDCRB1.86B.0119.R05.1701181843 DMI: Intel Corporation PURLEY/PURLEY, BIOS PLYDCRB1.86B.0119.R05.1701181843 01/18/2017 {1}[Hardware Error]: device_id: 0000:5d:00.0 {1}[Hardware Error]: slot: 0 {1}[Hardware Error]: secondary_bus: 0x5e {1}[Hardware Error]: vendor_id: 0x8086, device_id: 0x2030 {1}[Hardware Error]: class_code: 000406 ^^^^^^ (should be 060400) Signed-off-by: Lukas Wunner Signed-off-by: Ard Biesheuvel Cc: Ben Dooks Cc: Dave Young Cc: Jarkko Sakkinen Cc: Jerry Snitselaar Cc: Linus Torvalds Cc: Lyude Paul Cc: Matthew Garrett Cc: Octavian Purdila Cc: Peter Jones Cc: Peter Zijlstra Cc: Scott Talbert Cc: Thomas Gleixner Cc: linux-efi@vger.kernel.org Cc: linux-integrity@vger.kernel.org Link: https://lkml.kernel.org/r/20191002165904.8819-2-ard.biesheuvel@linaro.org Signed-off-by: Ingo Molnar --- drivers/firmware/efi/cper.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/firmware/efi/cper.c b/drivers/firmware/efi/cper.c index addf0749dd8b..b1af0de2e100 100644 --- a/drivers/firmware/efi/cper.c +++ b/drivers/firmware/efi/cper.c @@ -381,7 +381,7 @@ static void cper_print_pcie(const char *pfx, const struct cper_sec_pcie *pcie, printk("%s""vendor_id: 0x%04x, device_id: 0x%04x\n", pfx, pcie->device_id.vendor_id, pcie->device_id.device_id); p = pcie->device_id.class_code; - printk("%s""class_code: %02x%02x%02x\n", pfx, p[0], p[1], p[2]); + printk("%s""class_code: %02x%02x%02x\n", pfx, p[2], p[1], p[0]); } if (pcie->validation_bits & CPER_PCIE_VALID_SERIAL_NUMBER) printk("%s""serial number: 0x%04x, 0x%04x\n", pfx, From c05f8f92b701576b615f30aac31fabdc0648649b Mon Sep 17 00:00:00 2001 From: Ard Biesheuvel Date: Wed, 2 Oct 2019 18:58:59 +0200 Subject: [PATCH 2/8] efivar/ssdt: Don't iterate over EFI vars if no SSDT override was specified The kernel command line option efivar_ssdt= allows the name to be specified of an EFI variable containing an ACPI SSDT table that should be loaded into memory by the OS, and treated as if it was provided by the firmware. Currently, that code will always iterate over the EFI variables and compare each name with the provided name, even if the command line option wasn't set to begin with. So bail early when no variable name was provided. This works around a boot regression on the 2012 Mac Pro, as reported by Scott. Tested-by: Scott Talbert Signed-off-by: Ard Biesheuvel Cc: # v4.9+ Cc: Ben Dooks Cc: Dave Young Cc: Jarkko Sakkinen Cc: Jerry Snitselaar Cc: Linus Torvalds Cc: Lukas Wunner Cc: Lyude Paul Cc: Matthew Garrett Cc: Octavian Purdila Cc: Peter Jones Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: linux-efi@vger.kernel.org Cc: linux-integrity@vger.kernel.org Fixes: 475fb4e8b2f4 ("efi / ACPI: load SSTDs from EFI variables") Link: https://lkml.kernel.org/r/20191002165904.8819-3-ard.biesheuvel@linaro.org Signed-off-by: Ingo Molnar --- drivers/firmware/efi/efi.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/firmware/efi/efi.c b/drivers/firmware/efi/efi.c index 8d3e778e988b..69f00f7453a3 100644 --- a/drivers/firmware/efi/efi.c +++ b/drivers/firmware/efi/efi.c @@ -267,6 +267,9 @@ static __init int efivar_ssdt_load(void) void *data; int ret; + if (!efivar_ssdt[0]) + return 0; + ret = efivar_init(efivar_ssdt_iter, &entries, true, &entries); list_for_each_entry_safe(entry, aux, &entries, list) { From 047d50aee341d940350897c85799e56ae57c3849 Mon Sep 17 00:00:00 2001 From: Peter Jones Date: Wed, 2 Oct 2019 18:59:00 +0200 Subject: [PATCH 3/8] efi/tpm: Don't access event->count when it isn't mapped Some machines generate a lot of event log entries. When we're iterating over them, the code removes the old mapping and adds a new one, so once we cross the page boundary we're unmapping the page with the count on it. Hilarity ensues. This patch keeps the info from the header in local variables so we don't need to access that page again or keep track of if it's mapped. Tested-by: Lyude Paul Signed-off-by: Peter Jones Signed-off-by: Jarkko Sakkinen Signed-off-by: Ard Biesheuvel Reviewed-by: Jarkko Sakkinen Acked-by: Matthew Garrett Acked-by: Ard Biesheuvel Cc: Ben Dooks Cc: Dave Young Cc: Jerry Snitselaar Cc: Linus Torvalds Cc: Lukas Wunner Cc: Octavian Purdila Cc: Peter Zijlstra Cc: Scott Talbert Cc: Thomas Gleixner Cc: linux-efi@vger.kernel.org Cc: linux-integrity@vger.kernel.org Cc: stable@vger.kernel.org Fixes: 44038bc514a2 ("tpm: Abstract crypto agile event size calculations") Link: https://lkml.kernel.org/r/20191002165904.8819-4-ard.biesheuvel@linaro.org [ Minor edits. ] Signed-off-by: Ingo Molnar --- include/linux/tpm_eventlog.h | 14 +++++++++++--- 1 file changed, 11 insertions(+), 3 deletions(-) diff --git a/include/linux/tpm_eventlog.h b/include/linux/tpm_eventlog.h index 63238c84dc0b..b50cc3adca18 100644 --- a/include/linux/tpm_eventlog.h +++ b/include/linux/tpm_eventlog.h @@ -170,6 +170,7 @@ static inline int __calc_tpm2_event_size(struct tcg_pcr_event2_head *event, u16 halg; int i; int j; + u32 count, event_type; marker = event; marker_start = marker; @@ -190,16 +191,22 @@ static inline int __calc_tpm2_event_size(struct tcg_pcr_event2_head *event, } event = (struct tcg_pcr_event2_head *)mapping; + /* + * The loop below will unmap these fields if the log is larger than + * one page, so save them here for reference: + */ + count = READ_ONCE(event->count); + event_type = READ_ONCE(event->event_type); efispecid = (struct tcg_efi_specid_event_head *)event_header->event; /* Check if event is malformed. */ - if (event->count > efispecid->num_algs) { + if (count > efispecid->num_algs) { size = 0; goto out; } - for (i = 0; i < event->count; i++) { + for (i = 0; i < count; i++) { halg_size = sizeof(event->digests[i].alg_id); /* Map the digest's algorithm identifier */ @@ -256,8 +263,9 @@ static inline int __calc_tpm2_event_size(struct tcg_pcr_event2_head *event, + event_field->event_size; size = marker - marker_start; - if ((event->event_type == 0) && (event_field->event_size == 0)) + if (event_type == 0 && event_field->event_size == 0) size = 0; + out: if (do_mapping) TPM_MEMUNMAP(mapping, mapping_size); From 05c8c1ff81ed2eb9bad7c27cf92e55c864c16df8 Mon Sep 17 00:00:00 2001 From: Peter Jones Date: Wed, 2 Oct 2019 18:59:01 +0200 Subject: [PATCH 4/8] efi/tpm: Don't traverse an event log with no events When there are no entries to put into the final event log, some machines will return the template they would have populated anyway. In this case the nr_events field is 0, but the rest of the log is just garbage. This patch stops us from trying to iterate the table with __calc_tpm2_event_size() when the number of events in the table is 0. Tested-by: Lyude Paul Signed-off-by: Peter Jones Signed-off-by: Jarkko Sakkinen Signed-off-by: Ard Biesheuvel Reviewed-by: Jarkko Sakkinen Acked-by: Matthew Garrett Acked-by: Ard Biesheuvel Cc: Ben Dooks Cc: Dave Young Cc: Jerry Snitselaar Cc: Linus Torvalds Cc: Lukas Wunner Cc: Octavian Purdila Cc: Peter Zijlstra Cc: Scott Talbert Cc: Thomas Gleixner Cc: linux-efi@vger.kernel.org Cc: linux-integrity@vger.kernel.org Cc: stable@vger.kernel.org Fixes: c46f3405692d ("tpm: Reserve the TPM final events table") Link: https://lkml.kernel.org/r/20191002165904.8819-5-ard.biesheuvel@linaro.org Signed-off-by: Ingo Molnar --- drivers/firmware/efi/tpm.c | 15 ++++++++++----- 1 file changed, 10 insertions(+), 5 deletions(-) diff --git a/drivers/firmware/efi/tpm.c b/drivers/firmware/efi/tpm.c index 1d3f5ca3eaaf..b9ae5c6f9b9c 100644 --- a/drivers/firmware/efi/tpm.c +++ b/drivers/firmware/efi/tpm.c @@ -75,11 +75,16 @@ int __init efi_tpm_eventlog_init(void) goto out; } - tbl_size = tpm2_calc_event_log_size((void *)efi.tpm_final_log - + sizeof(final_tbl->version) - + sizeof(final_tbl->nr_events), - final_tbl->nr_events, - log_tbl->log); + tbl_size = 0; + if (final_tbl->nr_events != 0) { + void *events = (void *)efi.tpm_final_log + + sizeof(final_tbl->version) + + sizeof(final_tbl->nr_events); + + tbl_size = tpm2_calc_event_log_size(events, + final_tbl->nr_events, + log_tbl->log); + } memblock_reserve((unsigned long)final_tbl, tbl_size + sizeof(*final_tbl)); early_memunmap(final_tbl, sizeof(*final_tbl)); From e658c82be5561412c5e83b5e74e9da4830593f3e Mon Sep 17 00:00:00 2001 From: Jerry Snitselaar Date: Wed, 2 Oct 2019 18:59:02 +0200 Subject: [PATCH 5/8] efi/tpm: Only set 'efi_tpm_final_log_size' after successful event log parsing If __calc_tpm2_event_size() fails to parse an event it will return 0, resulting tpm2_calc_event_log_size() returning -1. Currently there is no check of this return value, and 'efi_tpm_final_log_size' can end up being set to this negative value resulting in a crash like this one: BUG: unable to handle page fault for address: ffffbc8fc00866ad #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page RIP: 0010:memcpy_erms+0x6/0x10 Call Trace: tpm_read_log_efi() tpm_bios_log_setup() tpm_chip_register() tpm_tis_core_init.cold.9+0x28c/0x466 tpm_tis_plat_probe() platform_drv_probe() ... Also __calc_tpm2_event_size() returns a size of 0 when it fails to parse an event, so update function documentation to reflect this. The root cause of the issue that caused the failure of event parsing in this case is resolved by Peter Jone's patchset dealing with large event logs where crossing over a page boundary causes the page with the event count to be unmapped. Signed-off-by: Jerry Snitselaar Signed-off-by: Ard Biesheuvel Cc: Ben Dooks Cc: Dave Young Cc: Jarkko Sakkinen Cc: Linus Torvalds Cc: Lukas Wunner Cc: Lyude Paul Cc: Matthew Garrett Cc: Octavian Purdila Cc: Peter Jones Cc: Peter Zijlstra Cc: Scott Talbert Cc: Thomas Gleixner Cc: linux-efi@vger.kernel.org Cc: linux-integrity@vger.kernel.org Cc: stable@vger.kernel.org Fixes: c46f3405692de ("tpm: Reserve the TPM final events table") Link: https://lkml.kernel.org/r/20191002165904.8819-6-ard.biesheuvel@linaro.org Signed-off-by: Ingo Molnar --- drivers/firmware/efi/tpm.c | 9 ++++++++- include/linux/tpm_eventlog.h | 2 +- 2 files changed, 9 insertions(+), 2 deletions(-) diff --git a/drivers/firmware/efi/tpm.c b/drivers/firmware/efi/tpm.c index b9ae5c6f9b9c..703469c1ab8e 100644 --- a/drivers/firmware/efi/tpm.c +++ b/drivers/firmware/efi/tpm.c @@ -85,11 +85,18 @@ int __init efi_tpm_eventlog_init(void) final_tbl->nr_events, log_tbl->log); } + + if (tbl_size < 0) { + pr_err(FW_BUG "Failed to parse event in TPM Final Events Log\n"); + goto out_calc; + } + memblock_reserve((unsigned long)final_tbl, tbl_size + sizeof(*final_tbl)); - early_memunmap(final_tbl, sizeof(*final_tbl)); efi_tpm_final_log_size = tbl_size; +out_calc: + early_memunmap(final_tbl, sizeof(*final_tbl)); out: early_memunmap(log_tbl, sizeof(*log_tbl)); return ret; diff --git a/include/linux/tpm_eventlog.h b/include/linux/tpm_eventlog.h index b50cc3adca18..131ea1bad458 100644 --- a/include/linux/tpm_eventlog.h +++ b/include/linux/tpm_eventlog.h @@ -152,7 +152,7 @@ struct tcg_algorithm_info { * total. Once we've done this we know the offset of the data length field, * and can calculate the total size of the event. * - * Return: size of the event on success, <0 on failure + * Return: size of the event on success, 0 on failure */ static inline int __calc_tpm2_event_size(struct tcg_pcr_event2_head *event, From 1ed121e61630fbf23fc0df1b8aa76debede5032b Mon Sep 17 00:00:00 2001 From: Ben Dooks Date: Wed, 2 Oct 2019 18:59:03 +0200 Subject: [PATCH 6/8] efi: Make unexported efi_rci2_sysfs_init() static The efi_rci2_sysfs_init() is not used outside of rci2-table.c so make it static to silence the following Sparse warning: drivers/firmware/efi/rci2-table.c:79:12: warning: symbol 'efi_rci2_sysfs_init' was not declared. Should it be static? Signed-off-by: Ben Dooks Signed-off-by: Ard Biesheuvel Cc: Dave Young Cc: Jarkko Sakkinen Cc: Jerry Snitselaar Cc: Linus Torvalds Cc: Lukas Wunner Cc: Lyude Paul Cc: Matthew Garrett Cc: Octavian Purdila Cc: Peter Jones Cc: Peter Zijlstra Cc: Scott Talbert Cc: Thomas Gleixner Cc: linux-efi@vger.kernel.org Cc: linux-integrity@vger.kernel.org Link: https://lkml.kernel.org/r/20191002165904.8819-7-ard.biesheuvel@linaro.org Signed-off-by: Ingo Molnar --- drivers/firmware/efi/rci2-table.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/firmware/efi/rci2-table.c b/drivers/firmware/efi/rci2-table.c index 3e290f96620a..76b0c354a027 100644 --- a/drivers/firmware/efi/rci2-table.c +++ b/drivers/firmware/efi/rci2-table.c @@ -76,7 +76,7 @@ static u16 checksum(void) return chksum; } -int __init efi_rci2_sysfs_init(void) +static int __init efi_rci2_sysfs_init(void) { struct kobject *tables_kobj; int ret = -ENOMEM; From 2ecb7402cfc7f22764e7bbc80790e66eadb20560 Mon Sep 17 00:00:00 2001 From: Dave Young Date: Wed, 2 Oct 2019 18:59:04 +0200 Subject: [PATCH 7/8] efi/x86: Do not clean dummy variable in kexec path kexec reboot fails randomly in UEFI based KVM guest. The firmware just resets while calling efi_delete_dummy_variable(); Unfortunately I don't know how to debug the firmware, it is also possible a potential problem on real hardware as well although nobody reproduced it. The intention of the efi_delete_dummy_variable is to trigger garbage collection when entering virtual mode. But SetVirtualAddressMap can only run once for each physical reboot, thus kexec_enter_virtual_mode() is not necessarily a good place to clean a dummy object. Drop the efi_delete_dummy_variable so that kexec reboot can work. Signed-off-by: Dave Young Signed-off-by: Ard Biesheuvel Acked-by: Matthew Garrett Cc: Ben Dooks Cc: Jarkko Sakkinen Cc: Jerry Snitselaar Cc: Linus Torvalds Cc: Lukas Wunner Cc: Lyude Paul Cc: Octavian Purdila Cc: Peter Jones Cc: Peter Zijlstra Cc: Scott Talbert Cc: Thomas Gleixner Cc: linux-efi@vger.kernel.org Cc: linux-integrity@vger.kernel.org Link: https://lkml.kernel.org/r/20191002165904.8819-8-ard.biesheuvel@linaro.org Signed-off-by: Ingo Molnar --- arch/x86/platform/efi/efi.c | 3 --- 1 file changed, 3 deletions(-) diff --git a/arch/x86/platform/efi/efi.c b/arch/x86/platform/efi/efi.c index c202e1b07e29..425e025341db 100644 --- a/arch/x86/platform/efi/efi.c +++ b/arch/x86/platform/efi/efi.c @@ -917,9 +917,6 @@ static void __init kexec_enter_virtual_mode(void) if (efi_enabled(EFI_OLD_MEMMAP) && (__supported_pte_mask & _PAGE_NX)) runtime_code_page_mkexec(); - - /* clean DUMMY object */ - efi_delete_dummy_variable(); #endif } From be59d57f98065af0b8472f66a0a969207b168680 Mon Sep 17 00:00:00 2001 From: Colin Ian King Date: Tue, 8 Oct 2019 11:01:53 +0100 Subject: [PATCH 8/8] efi/tpm: Fix sanity check of unsigned tbl_size being less than zero Currently the check for tbl_size being less than zero is always false because tbl_size is unsigned. Fix this by making it a signed int. Addresses-Coverity: ("Unsigned compared against 0") Signed-off-by: Colin Ian King Cc: Ard Biesheuvel Cc: Jerry Snitselaar Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: kernel-janitors@vger.kernel.org Cc: linux-efi@vger.kernel.org Fixes: e658c82be556 ("efi/tpm: Only set 'efi_tpm_final_log_size' after successful event log parsing") Link: https://lkml.kernel.org/r/20191008100153.8499-1-colin.king@canonical.com Signed-off-by: Ingo Molnar --- drivers/firmware/efi/tpm.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/firmware/efi/tpm.c b/drivers/firmware/efi/tpm.c index 703469c1ab8e..ebd7977653a8 100644 --- a/drivers/firmware/efi/tpm.c +++ b/drivers/firmware/efi/tpm.c @@ -40,7 +40,7 @@ int __init efi_tpm_eventlog_init(void) { struct linux_efi_tpm_eventlog *log_tbl; struct efi_tcg2_final_events_table *final_tbl; - unsigned int tbl_size; + int tbl_size; int ret = 0; if (efi.tpm_log == EFI_INVALID_TABLE_ADDR) {