From 174e5e9da4f5946de3d09c32ee56cbbc9d70505b Mon Sep 17 00:00:00 2001 From: Patrick Rudolph Date: Fri, 21 Feb 2025 09:12:42 +0100 Subject: efi/cper: Fix cper_ia_proc_ctx alignment According to the UEFI Common Platform Error Record appendix, the IA32/X64 Processor Context Information Structure is a variable length structure, but "is padded with zeros if the size is not a multiple of 16 bytes". Currently this isn't honoured, causing all but the first structure to be garbage when printed. Thus align the size to be a multiple of 16. Signed-off-by: Patrick Rudolph Signed-off-by: Ard Biesheuvel --- drivers/firmware/efi/cper-x86.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'drivers/firmware') diff --git a/drivers/firmware/efi/cper-x86.c b/drivers/firmware/efi/cper-x86.c index 438ed9eff6d0..3949d7b5e808 100644 --- a/drivers/firmware/efi/cper-x86.c +++ b/drivers/firmware/efi/cper-x86.c @@ -325,7 +325,7 @@ void cper_print_proc_ia(const char *pfx, const struct cper_sec_proc_ia *proc) ctx_info = (struct cper_ia_proc_ctx *)err_info; for (i = 0; i < VALID_PROC_CXT_INFO_NUM(proc->validation_bits); i++) { - int size = sizeof(*ctx_info) + ctx_info->reg_arr_size; + int size = ALIGN(sizeof(*ctx_info) + ctx_info->reg_arr_size, 16); int groupsize = 4; printk("%sContext Information Structure %d:\n", pfx, i); -- cgit v1.2.3 From d6a2d02aa060531607f4a8411ec384470faa2761 Mon Sep 17 00:00:00 2001 From: Patrick Rudolph Date: Fri, 21 Feb 2025 12:15:16 +0100 Subject: efi/cper: Fix cper_arm_ctx_info alignment According to the UEFI Common Platform Error Record appendix, the processor context information structure is a variable length structure, but "is padded with zeros if the size is not a multiple of 16 bytes". Currently this isn't honoured, causing all but the first structure to be garbage when printed. Thus align the size to be a multiple of 16. Signed-off-by: Patrick Rudolph Signed-off-by: Ard Biesheuvel --- drivers/firmware/efi/cper-arm.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'drivers/firmware') diff --git a/drivers/firmware/efi/cper-arm.c b/drivers/firmware/efi/cper-arm.c index fa9c1c3bf168..f0a63d09d3c4 100644 --- a/drivers/firmware/efi/cper-arm.c +++ b/drivers/firmware/efi/cper-arm.c @@ -311,7 +311,7 @@ void cper_print_proc_arm(const char *pfx, ctx_info = (struct cper_arm_ctx_info *)err_info; max_ctx_type = ARRAY_SIZE(arm_reg_ctx_strs) - 1; for (i = 0; i < proc->context_info_num; i++) { - int size = sizeof(*ctx_info) + ctx_info->size; + int size = ALIGN(sizeof(*ctx_info) + ctx_info->size, 16); printk("%sContext info structure %d:\n", pfx, i); if (len < size) { -- cgit v1.2.3 From 2b90e7ace79774a3540ce569e000388f8d22c9e0 Mon Sep 17 00:00:00 2001 From: Peter Jones Date: Wed, 26 Feb 2025 15:18:39 -0500 Subject: efi: Don't map the entire mokvar table to determine its size Currently, when validating the mokvar table, we (re)map the entire table on each iteration of the loop, adding space as we discover new entries. If the table grows over a certain size, this fails due to limitations of early_memmap(), and we get a failure and traceback: ------------[ cut here ]------------ WARNING: CPU: 0 PID: 0 at mm/early_ioremap.c:139 __early_ioremap+0xef/0x220 ... Call Trace: ? __early_ioremap+0xef/0x220 ? __warn.cold+0x93/0xfa ? __early_ioremap+0xef/0x220 ? report_bug+0xff/0x140 ? early_fixup_exception+0x5d/0xb0 ? early_idt_handler_common+0x2f/0x3a ? __early_ioremap+0xef/0x220 ? efi_mokvar_table_init+0xce/0x1d0 ? setup_arch+0x864/0xc10 ? start_kernel+0x6b/0xa10 ? x86_64_start_reservations+0x24/0x30 ? x86_64_start_kernel+0xed/0xf0 ? common_startup_64+0x13e/0x141 ---[ end trace 0000000000000000 ]--- mokvar: Failed to map EFI MOKvar config table pa=0x7c4c3000, size=265187. Mapping the entire structure isn't actually necessary, as we don't ever need more than one entry header mapped at once. Changes efi_mokvar_table_init() to only map each entry header, not the entire table, when determining the table size. Since we're not mapping any data past the variable name, it also changes the code to enforce that each variable name is NUL terminated, rather than attempting to verify it in place. Cc: Signed-off-by: Peter Jones Signed-off-by: Ard Biesheuvel --- drivers/firmware/efi/mokvar-table.c | 41 ++++++++++++------------------------- 1 file changed, 13 insertions(+), 28 deletions(-) (limited to 'drivers/firmware') diff --git a/drivers/firmware/efi/mokvar-table.c b/drivers/firmware/efi/mokvar-table.c index 5ed0602c2f75..d865cb1dbaad 100644 --- a/drivers/firmware/efi/mokvar-table.c +++ b/drivers/firmware/efi/mokvar-table.c @@ -103,7 +103,6 @@ void __init efi_mokvar_table_init(void) void *va = NULL; unsigned long cur_offset = 0; unsigned long offset_limit; - unsigned long map_size = 0; unsigned long map_size_needed = 0; unsigned long size; struct efi_mokvar_table_entry *mokvar_entry; @@ -134,48 +133,34 @@ void __init efi_mokvar_table_init(void) */ err = -EINVAL; while (cur_offset + sizeof(*mokvar_entry) <= offset_limit) { - mokvar_entry = va + cur_offset; - map_size_needed = cur_offset + sizeof(*mokvar_entry); - if (map_size_needed > map_size) { - if (va) - early_memunmap(va, map_size); - /* - * Map a little more than the fixed size entry - * header, anticipating some data. It's safe to - * do so as long as we stay within current memory - * descriptor. - */ - map_size = min(map_size_needed + 2*EFI_PAGE_SIZE, - offset_limit); - va = early_memremap(efi.mokvar_table, map_size); - if (!va) { - pr_err("Failed to map EFI MOKvar config table pa=0x%lx, size=%lu.\n", - efi.mokvar_table, map_size); - return; - } - mokvar_entry = va + cur_offset; + if (va) + early_memunmap(va, sizeof(*mokvar_entry)); + va = early_memremap(efi.mokvar_table + cur_offset, sizeof(*mokvar_entry)); + if (!va) { + pr_err("Failed to map EFI MOKvar config table pa=0x%lx, size=%zu.\n", + efi.mokvar_table + cur_offset, sizeof(*mokvar_entry)); + return; } + mokvar_entry = va; /* Check for last sentinel entry */ if (mokvar_entry->name[0] == '\0') { if (mokvar_entry->data_size != 0) break; err = 0; + map_size_needed = cur_offset + sizeof(*mokvar_entry); break; } - /* Sanity check that the name is null terminated */ - size = strnlen(mokvar_entry->name, - sizeof(mokvar_entry->name)); - if (size >= sizeof(mokvar_entry->name)) - break; + /* Enforce that the name is NUL terminated */ + mokvar_entry->name[sizeof(mokvar_entry->name) - 1] = '\0'; /* Advance to the next entry */ - cur_offset = map_size_needed + mokvar_entry->data_size; + cur_offset += sizeof(*mokvar_entry) + mokvar_entry->data_size; } if (va) - early_memunmap(va, map_size); + early_memunmap(va, sizeof(*mokvar_entry)); if (err) { pr_err("EFI MOKvar config table is not valid\n"); return; -- cgit v1.2.3 From e3cf2d91d0583cae70aeb512da87e3ade25ea912 Mon Sep 17 00:00:00 2001 From: Ard Biesheuvel Date: Thu, 27 Feb 2025 14:30:22 +0100 Subject: efi/mokvar-table: Avoid repeated map/unmap of the same page Tweak the logic that traverses the MOKVAR UEFI configuration table to only unmap the entry header and map the next one if they don't live in the same physical page. Link: https://lore.kernel.org/all/8f085931-3e9d-4386-9209-1d6c95616327@uncooperative.org/ Tested-By: Peter Jones Signed-off-by: Ard Biesheuvel --- drivers/firmware/efi/mokvar-table.c | 18 +++++++++++++++--- 1 file changed, 15 insertions(+), 3 deletions(-) (limited to 'drivers/firmware') diff --git a/drivers/firmware/efi/mokvar-table.c b/drivers/firmware/efi/mokvar-table.c index d865cb1dbaad..208db29613c6 100644 --- a/drivers/firmware/efi/mokvar-table.c +++ b/drivers/firmware/efi/mokvar-table.c @@ -99,13 +99,13 @@ static struct kobject *mokvar_kobj; */ void __init efi_mokvar_table_init(void) { + struct efi_mokvar_table_entry __aligned(1) *mokvar_entry, *next_entry; efi_memory_desc_t md; void *va = NULL; unsigned long cur_offset = 0; unsigned long offset_limit; unsigned long map_size_needed = 0; unsigned long size; - struct efi_mokvar_table_entry *mokvar_entry; int err; if (!efi_enabled(EFI_MEMMAP)) @@ -142,7 +142,7 @@ void __init efi_mokvar_table_init(void) return; } mokvar_entry = va; - +next: /* Check for last sentinel entry */ if (mokvar_entry->name[0] == '\0') { if (mokvar_entry->data_size != 0) @@ -156,7 +156,19 @@ void __init efi_mokvar_table_init(void) mokvar_entry->name[sizeof(mokvar_entry->name) - 1] = '\0'; /* Advance to the next entry */ - cur_offset += sizeof(*mokvar_entry) + mokvar_entry->data_size; + size = sizeof(*mokvar_entry) + mokvar_entry->data_size; + cur_offset += size; + + /* + * Don't bother remapping if the current entry header and the + * next one end on the same page. + */ + next_entry = (void *)((unsigned long)mokvar_entry + size); + if (((((unsigned long)(mokvar_entry + 1) - 1) ^ + ((unsigned long)(next_entry + 1) - 1)) & PAGE_MASK) == 0) { + mokvar_entry = next_entry; + goto next; + } } if (va) -- cgit v1.2.3