diff options
Diffstat (limited to 'drivers/firmware/efi/libstub/x86-stub.c')
| -rw-r--r-- | drivers/firmware/efi/libstub/x86-stub.c | 833 |
1 files changed, 545 insertions, 288 deletions
diff --git a/drivers/firmware/efi/libstub/x86-stub.c b/drivers/firmware/efi/libstub/x86-stub.c index f14c4ff5839f..cef32e2c82d8 100644 --- a/drivers/firmware/efi/libstub/x86-stub.c +++ b/drivers/firmware/efi/libstub/x86-stub.c @@ -15,20 +15,34 @@ #include <asm/setup.h> #include <asm/desc.h> #include <asm/boot.h> +#include <asm/kaslr.h> +#include <asm/sev.h> #include "efistub.h" +#include "x86-stub.h" -/* Maximum physical address for 64-bit kernel with 4-level paging */ -#define MAXMEM_X86_64_4LEVEL (1ull << 46) +extern char _bss[], _ebss[]; const efi_system_table_t *efi_system_table; -extern u32 image_offset; +const efi_dxe_services_table_t *efi_dxe_table; static efi_loaded_image_t *image = NULL; +static efi_memory_attribute_protocol_t *memattr; + +typedef union sev_memory_acceptance_protocol sev_memory_acceptance_protocol_t; +union sev_memory_acceptance_protocol { + struct { + efi_status_t (__efiapi * allow_unaccepted_memory)( + sev_memory_acceptance_protocol_t *); + }; + struct { + u32 allow_unaccepted_memory; + } mixed_mode; +}; static efi_status_t preserve_pci_rom_image(efi_pci_io_protocol_t *pci, struct pci_setup_rom **__rom) { - struct pci_setup_rom *rom = NULL; + struct pci_setup_rom *rom __free(efi_pool) = NULL; efi_status_t status; unsigned long size; uint64_t romsize; @@ -60,15 +74,14 @@ preserve_pci_rom_image(efi_pci_io_protocol_t *pci, struct pci_setup_rom **__rom) rom->data.type = SETUP_PCI; rom->data.len = size - sizeof(struct setup_data); rom->data.next = 0; - rom->pcilen = pci->romsize; - *__rom = rom; + rom->pcilen = romsize; status = efi_call_proto(pci, pci.read, EfiPciIoWidthUint16, PCI_VENDOR_ID, 1, &rom->vendor); if (status != EFI_SUCCESS) { efi_err("Failed to read rom->vendor\n"); - goto free_struct; + return status; } status = efi_call_proto(pci, pci.read, EfiPciIoWidthUint16, @@ -76,21 +89,18 @@ preserve_pci_rom_image(efi_pci_io_protocol_t *pci, struct pci_setup_rom **__rom) if (status != EFI_SUCCESS) { efi_err("Failed to read rom->devid\n"); - goto free_struct; + return status; } status = efi_call_proto(pci, get_location, &rom->segment, &rom->bus, &rom->device, &rom->function); if (status != EFI_SUCCESS) - goto free_struct; + return status; memcpy(rom->romdata, romimage, romsize); - return status; - -free_struct: - efi_bs_call(free_pool, rom); - return status; + *__rom = no_free_ptr(rom); + return EFI_SUCCESS; } /* @@ -105,38 +115,23 @@ free_struct: static void setup_efi_pci(struct boot_params *params) { efi_status_t status; - void **pci_handle = NULL; + efi_handle_t *pci_handle __free(efi_pool) = NULL; efi_guid_t pci_proto = EFI_PCI_IO_PROTOCOL_GUID; - unsigned long size = 0; struct setup_data *data; + unsigned long num; efi_handle_t h; - int i; - - status = efi_bs_call(locate_handle, EFI_LOCATE_BY_PROTOCOL, - &pci_proto, NULL, &size, pci_handle); - - if (status == EFI_BUFFER_TOO_SMALL) { - status = efi_bs_call(allocate_pool, EFI_LOADER_DATA, size, - (void **)&pci_handle); - - if (status != EFI_SUCCESS) { - efi_err("Failed to allocate memory for 'pci_handle'\n"); - return; - } - - status = efi_bs_call(locate_handle, EFI_LOCATE_BY_PROTOCOL, - &pci_proto, NULL, &size, pci_handle); - } + status = efi_bs_call(locate_handle_buffer, EFI_LOCATE_BY_PROTOCOL, + &pci_proto, NULL, &num, &pci_handle); if (status != EFI_SUCCESS) - goto free_handle; + return; data = (struct setup_data *)(unsigned long)params->hdr.setup_data; while (data && data->next) data = (struct setup_data *)(unsigned long)data->next; - for_each_efi_handle(h, pci_handle, size, i) { + for_each_efi_handle(h, pci_handle, num) { efi_pci_io_protocol_t *pci = NULL; struct pci_setup_rom *rom; @@ -156,9 +151,6 @@ static void setup_efi_pci(struct boot_params *params) data = (struct setup_data *)rom; } - -free_handle: - efi_bs_call(free_pool, pci_handle); } static void retrieve_apple_device_properties(struct boot_params *boot_params) @@ -211,128 +203,294 @@ static void retrieve_apple_device_properties(struct boot_params *boot_params) } } -static const efi_char16_t apple[] = L"Apple"; +struct smbios_entry_point { + u8 anchor[4]; + u8 ep_checksum; + u8 ep_length; + u8 major_version; + u8 minor_version; + u16 max_size_entry; + u8 ep_rev; + u8 reserved[5]; + + struct __packed { + u8 anchor[5]; + u8 checksum; + u16 st_length; + u32 st_address; + u16 number_of_entries; + u8 bcd_rev; + } intm; +}; -static void setup_quirks(struct boot_params *boot_params) +static bool verify_ep_checksum(const void *ptr, int length) { - efi_char16_t *fw_vendor = (efi_char16_t *)(unsigned long) - efi_table_attr(efi_system_table, fw_vendor); + u8 sum = 0; - if (!memcmp(fw_vendor, apple, sizeof(apple))) { - if (IS_ENABLED(CONFIG_APPLE_PROPERTIES)) - retrieve_apple_device_properties(boot_params); + for (int i = 0; i < length; i++) + sum += ((u8 *)ptr)[i]; + + return sum == 0; +} + +static bool verify_ep_integrity(const struct smbios_entry_point *ep) +{ + if (memcmp(ep->anchor, "_SM_", sizeof(ep->anchor)) != 0) + return false; + + if (memcmp(ep->intm.anchor, "_DMI_", sizeof(ep->intm.anchor)) != 0) + return false; + + if (!verify_ep_checksum(ep, ep->ep_length) || + !verify_ep_checksum(&ep->intm, sizeof(ep->intm))) + return false; + + return true; +} + +static const struct efi_smbios_record *search_record(void *table, u32 length, + u8 type) +{ + const u8 *p, *end; + + p = (u8 *)table; + end = p + length; + + while (p + sizeof(struct efi_smbios_record) < end) { + const struct efi_smbios_record *hdr = + (struct efi_smbios_record *)p; + const u8 *next; + + if (hdr->type == type) + return hdr; + + /* Type 127 = End-of-Table */ + if (hdr->type == 0x7F) + return NULL; + + /* Jumping to the unformed section */ + next = p + hdr->length; + + /* Unformed section ends with 0000h */ + while ((next[0] != 0 || next[1] != 0) && next + 1 < end) + next++; + + next += 2; + p = next; } + + return NULL; } -/* - * See if we have Universal Graphics Adapter (UGA) protocol - */ -static efi_status_t -setup_uga(struct screen_info *si, efi_guid_t *uga_proto, unsigned long size) +static const struct efi_smbios_record *get_table_record(u8 type) { + const struct smbios_entry_point *ep; + + /* + * Locate the legacy 32-bit SMBIOS entrypoint in memory, and parse it + * directly. Needed by some Macs that do not implement the EFI protocol. + */ + ep = get_efi_config_table(SMBIOS_TABLE_GUID); + if (!ep) + return NULL; + + if (!verify_ep_integrity(ep)) + return NULL; + + return search_record((void *)(unsigned long)ep->intm.st_address, + ep->intm.st_length, type); +} + +static bool apple_match_product_name(void) +{ + static const char type1_product_matches[][15] = { + "MacBookPro11,3", + "MacBookPro11,5", + "MacBookPro13,3", + "MacBookPro14,3", + "MacBookPro15,1", + "MacBookPro15,3", + "MacBookPro16,1", + "MacBookPro16,4", + }; + const struct efi_smbios_type1_record *record; + const u8 *product; + + record = (struct efi_smbios_type1_record *) + (efi_get_smbios_record(1) ?: get_table_record(1)); + if (!record) + return false; + + product = efi_get_smbios_string(record, product_name); + if (!product) + return false; + + for (int i = 0; i < ARRAY_SIZE(type1_product_matches); i++) { + if (!strcmp(product, type1_product_matches[i])) + return true; + } + + return false; +} + +static void apple_set_os(void) +{ + struct { + unsigned long version; + efi_status_t (__efiapi *set_os_version)(const char *); + efi_status_t (__efiapi *set_os_vendor)(const char *); + } *set_os; efi_status_t status; - u32 width, height; - void **uga_handle = NULL; - efi_uga_draw_protocol_t *uga = NULL, *first_uga; - efi_handle_t handle; - int i; - status = efi_bs_call(allocate_pool, EFI_LOADER_DATA, size, - (void **)&uga_handle); - if (status != EFI_SUCCESS) - return status; + if (!efi_is_64bit() || !apple_match_product_name()) + return; - status = efi_bs_call(locate_handle, EFI_LOCATE_BY_PROTOCOL, - uga_proto, NULL, &size, uga_handle); + status = efi_bs_call(locate_protocol, &APPLE_SET_OS_PROTOCOL_GUID, NULL, + (void **)&set_os); if (status != EFI_SUCCESS) - goto free_handle; + return; + + if (set_os->version >= 2) { + status = set_os->set_os_vendor("Apple Inc."); + if (status != EFI_SUCCESS) + efi_err("Failed to set OS vendor via apple_set_os\n"); + } - height = 0; - width = 0; + if (set_os->version > 0) { + /* The version being set doesn't seem to matter */ + status = set_os->set_os_version("Mac OS X 10.9"); + if (status != EFI_SUCCESS) + efi_err("Failed to set OS version via apple_set_os\n"); + } +} - first_uga = NULL; - for_each_efi_handle(handle, uga_handle, size, i) { - efi_guid_t pciio_proto = EFI_PCI_IO_PROTOCOL_GUID; - u32 w, h, depth, refresh; - void *pciio; +efi_status_t efi_adjust_memory_range_protection(unsigned long start, + unsigned long size) +{ + efi_status_t status; + efi_gcd_memory_space_desc_t desc; + unsigned long end, next; + unsigned long rounded_start, rounded_end; + unsigned long unprotect_start, unprotect_size; + + rounded_start = rounddown(start, EFI_PAGE_SIZE); + rounded_end = roundup(start + size, EFI_PAGE_SIZE); + + if (memattr != NULL) { + status = efi_call_proto(memattr, set_memory_attributes, + rounded_start, + rounded_end - rounded_start, + EFI_MEMORY_RO); + if (status != EFI_SUCCESS) { + efi_warn("Failed to set EFI_MEMORY_RO attribute\n"); + return status; + } - status = efi_bs_call(handle_protocol, handle, uga_proto, - (void **)&uga); + status = efi_call_proto(memattr, clear_memory_attributes, + rounded_start, + rounded_end - rounded_start, + EFI_MEMORY_XP); if (status != EFI_SUCCESS) - continue; + efi_warn("Failed to clear EFI_MEMORY_XP attribute\n"); + return status; + } - pciio = NULL; - efi_bs_call(handle_protocol, handle, &pciio_proto, &pciio); + if (efi_dxe_table == NULL) + return EFI_SUCCESS; + + /* + * Don't modify memory region attributes, if they are + * already suitable, to lower the possibility to + * encounter firmware bugs. + */ - status = efi_call_proto(uga, get_mode, &w, &h, &depth, &refresh); - if (status == EFI_SUCCESS && (!first_uga || pciio)) { - width = w; - height = h; + for (end = start + size; start < end; start = next) { - /* - * Once we've found a UGA supporting PCIIO, - * don't bother looking any further. - */ - if (pciio) - break; + status = efi_dxe_call(get_memory_space_descriptor, start, &desc); - first_uga = uga; - } - } + if (status != EFI_SUCCESS) + break; - if (!width && !height) - goto free_handle; + next = desc.base_address + desc.length; - /* EFI framebuffer */ - si->orig_video_isVGA = VIDEO_TYPE_EFI; + /* + * Only system memory and more reliable memory are suitable for + * trampoline/kernel image placement. So only those memory types + * may need to have attributes modified. + */ - si->lfb_depth = 32; - si->lfb_width = width; - si->lfb_height = height; + if ((desc.gcd_memory_type != EfiGcdMemoryTypeSystemMemory && + desc.gcd_memory_type != EfiGcdMemoryTypeMoreReliable) || + (desc.attributes & (EFI_MEMORY_RO | EFI_MEMORY_XP)) == 0) + continue; - si->red_size = 8; - si->red_pos = 16; - si->green_size = 8; - si->green_pos = 8; - si->blue_size = 8; - si->blue_pos = 0; - si->rsvd_size = 8; - si->rsvd_pos = 24; + unprotect_start = max(rounded_start, (unsigned long)desc.base_address); + unprotect_size = min(rounded_end, next) - unprotect_start; -free_handle: - efi_bs_call(free_pool, uga_handle); + status = efi_dxe_call(set_memory_space_attributes, + unprotect_start, unprotect_size, + EFI_MEMORY_WB); - return status; + if (status != EFI_SUCCESS) { + efi_warn("Unable to unprotect memory range [%08lx,%08lx]: %lx\n", + unprotect_start, + unprotect_start + unprotect_size, + status); + break; + } + } + return EFI_SUCCESS; } -static void setup_graphics(struct boot_params *boot_params) +static void setup_unaccepted_memory(void) { - efi_guid_t graphics_proto = EFI_GRAPHICS_OUTPUT_PROTOCOL_GUID; - struct screen_info *si; - efi_guid_t uga_proto = EFI_UGA_PROTOCOL_GUID; + efi_guid_t mem_acceptance_proto = OVMF_SEV_MEMORY_ACCEPTANCE_PROTOCOL_GUID; + sev_memory_acceptance_protocol_t *proto; efi_status_t status; - unsigned long size; - void **gop_handle = NULL; - void **uga_handle = NULL; - si = &boot_params->screen_info; - memset(si, 0, sizeof(*si)); + if (!IS_ENABLED(CONFIG_UNACCEPTED_MEMORY)) + return; - size = 0; - status = efi_bs_call(locate_handle, EFI_LOCATE_BY_PROTOCOL, - &graphics_proto, NULL, &size, gop_handle); - if (status == EFI_BUFFER_TOO_SMALL) - status = efi_setup_gop(si, &graphics_proto, size); + /* + * Enable unaccepted memory before calling exit boot services in order + * for the UEFI to not accept all memory on EBS. + */ + status = efi_bs_call(locate_protocol, &mem_acceptance_proto, NULL, + (void **)&proto); + if (status != EFI_SUCCESS) + return; - if (status != EFI_SUCCESS) { - size = 0; - status = efi_bs_call(locate_handle, EFI_LOCATE_BY_PROTOCOL, - &uga_proto, NULL, &size, uga_handle); - if (status == EFI_BUFFER_TOO_SMALL) - setup_uga(si, &uga_proto, size); + status = efi_call_proto(proto, allow_unaccepted_memory); + if (status != EFI_SUCCESS) + efi_err("Memory acceptance protocol failed\n"); +} + +static efi_char16_t *efistub_fw_vendor(void) +{ + unsigned long vendor = efi_table_attr(efi_system_table, fw_vendor); + + return (efi_char16_t *)vendor; +} + +static const efi_char16_t apple[] = L"Apple"; + +static void setup_quirks(struct boot_params *boot_params) +{ + if (!memcmp(efistub_fw_vendor(), apple, sizeof(apple))) { + if (IS_ENABLED(CONFIG_APPLE_PROPERTIES)) + retrieve_apple_device_properties(boot_params); + + apple_set_os(); } } +static void setup_graphics(struct boot_params *boot_params) +{ + struct screen_info *si = memset(&boot_params->screen_info, 0, sizeof(*si)); + struct edid_info *edid = memset(&boot_params->edid_info, 0, sizeof(*edid)); + + efi_setup_graphics(si, edid); +} static void __noreturn efi_exit(efi_handle_t handle, efi_status_t status) { @@ -341,86 +499,53 @@ static void __noreturn efi_exit(efi_handle_t handle, efi_status_t status) asm("hlt"); } -void startup_32(struct boot_params *boot_params); - -void __noreturn efi_stub_entry(efi_handle_t handle, - efi_system_table_t *sys_table_arg, - struct boot_params *boot_params); - /* * Because the x86 boot code expects to be passed a boot_params we * need to create one ourselves (usually the bootloader would create * one for us). */ -efi_status_t __efiapi efi_pe_entry(efi_handle_t handle, - efi_system_table_t *sys_table_arg) +static efi_status_t efi_allocate_bootparams(efi_handle_t handle, + struct boot_params **bp) { + efi_guid_t proto = LOADED_IMAGE_PROTOCOL_GUID; struct boot_params *boot_params; struct setup_header *hdr; - void *image_base; - efi_guid_t proto = LOADED_IMAGE_PROTOCOL_GUID; - int options_size = 0; efi_status_t status; + unsigned long alloc; char *cmdline_ptr; - efi_system_table = sys_table_arg; - - /* Check if we were booted by the EFI firmware */ - if (efi_system_table->hdr.signature != EFI_SYSTEM_TABLE_SIGNATURE) - efi_exit(handle, EFI_INVALID_PARAMETER); - status = efi_bs_call(handle_protocol, handle, &proto, (void **)&image); if (status != EFI_SUCCESS) { efi_err("Failed to get handle for LOADED_IMAGE_PROTOCOL\n"); - efi_exit(handle, status); - } - - image_base = efi_table_attr(image, image_base); - image_offset = (void *)startup_32 - image_base; - - status = efi_allocate_pages(sizeof(struct boot_params), - (unsigned long *)&boot_params, ULONG_MAX); - if (status != EFI_SUCCESS) { - efi_err("Failed to allocate lowmem for boot params\n"); - efi_exit(handle, status); + return status; } - memset(boot_params, 0x0, sizeof(struct boot_params)); - - hdr = &boot_params->hdr; + status = efi_allocate_pages(PARAM_SIZE, &alloc, ULONG_MAX); + if (status != EFI_SUCCESS) + return status; - /* Copy the setup header from the second sector to boot_params */ - memcpy(&hdr->jump, image_base + 512, - sizeof(struct setup_header) - offsetof(struct setup_header, jump)); + boot_params = memset((void *)alloc, 0x0, PARAM_SIZE); + hdr = &boot_params->hdr; - /* - * Fill out some of the header fields ourselves because the - * EFI firmware loader doesn't load the first sector. - */ + /* Assign the setup_header fields that the kernel actually cares about */ hdr->root_flags = 1; hdr->vid_mode = 0xffff; - hdr->boot_flag = 0xAA55; hdr->type_of_loader = 0x21; + hdr->initrd_addr_max = INT_MAX; /* Convert unicode cmdline to ascii */ - cmdline_ptr = efi_convert_cmdline(image, &options_size); - if (!cmdline_ptr) - goto fail; - - efi_set_u64_split((unsigned long)cmdline_ptr, - &hdr->cmd_line_ptr, &boot_params->ext_cmd_line_ptr); - - hdr->ramdisk_image = 0; - hdr->ramdisk_size = 0; - - efi_stub_entry(handle, sys_table_arg, boot_params); - /* not reached */ + cmdline_ptr = efi_convert_cmdline(image); + if (!cmdline_ptr) { + efi_free(PARAM_SIZE, alloc); + return EFI_OUT_OF_RESOURCES; + } -fail: - efi_free(sizeof(struct boot_params), (unsigned long)boot_params); + efi_set_u64_split((unsigned long)cmdline_ptr, &hdr->cmd_line_ptr, + &boot_params->ext_cmd_line_ptr); - efi_exit(handle, status); + *bp = boot_params; + return EFI_SUCCESS; } static void add_e820ext(struct boot_params *params, @@ -465,7 +590,7 @@ setup_e820(struct boot_params *params, struct setup_data *e820ext, u32 e820ext_s m |= (u64)efi->efi_memmap_hi << 32; #endif - d = efi_early_memdesc_ptr(m, efi->efi_memdesc_size, i); + d = efi_memdesc_ptr(m, efi->efi_memdesc_size, i); switch (d->type) { case EFI_RESERVED_TYPE: case EFI_RUNTIME_SERVICES_CODE: @@ -504,6 +629,13 @@ setup_e820(struct boot_params *params, struct setup_data *e820ext, u32 e820ext_s e820_type = E820_TYPE_PMEM; break; + case EFI_UNACCEPTED_MEMORY: + if (!IS_ENABLED(CONFIG_UNACCEPTED_MEMORY)) + continue; + e820_type = E820_TYPE_RAM; + process_unaccepted_memory(d->phys_addr, + d->phys_addr + PAGE_SIZE * d->num_pages); + break; default: continue; } @@ -572,27 +704,27 @@ static efi_status_t allocate_e820(struct boot_params *params, struct setup_data **e820ext, u32 *e820ext_size) { - unsigned long map_size, desc_size, map_key; + struct efi_boot_memmap *map __free(efi_pool) = NULL; efi_status_t status; - __u32 nr_desc, desc_version; + __u32 nr_desc; - /* Only need the size of the mem map and size of each mem descriptor */ - map_size = 0; - status = efi_bs_call(get_memory_map, &map_size, NULL, &map_key, - &desc_size, &desc_version); - if (status != EFI_BUFFER_TOO_SMALL) - return (status != EFI_SUCCESS) ? status : EFI_UNSUPPORTED; - - nr_desc = map_size / desc_size + EFI_MMAP_NR_SLACK_SLOTS; + status = efi_get_memory_map(&map, false); + if (status != EFI_SUCCESS) + return status; - if (nr_desc > ARRAY_SIZE(params->e820_table)) { - u32 nr_e820ext = nr_desc - ARRAY_SIZE(params->e820_table); + nr_desc = map->map_size / map->desc_size; + if (nr_desc > ARRAY_SIZE(params->e820_table) - EFI_MMAP_NR_SLACK_SLOTS) { + u32 nr_e820ext = nr_desc - ARRAY_SIZE(params->e820_table) + + EFI_MMAP_NR_SLACK_SLOTS; status = alloc_e820ext(nr_e820ext, e820ext, e820ext_size); if (status != EFI_SUCCESS) return status; } + if (IS_ENABLED(CONFIG_UNACCEPTED_MEMORY)) + return allocate_unaccepted_bitmap(nr_desc, map); + return EFI_SUCCESS; } @@ -613,32 +745,22 @@ static efi_status_t exit_boot_func(struct efi_boot_memmap *map, efi_set_u64_split((unsigned long)efi_system_table, &p->efi->efi_systab, &p->efi->efi_systab_hi); - p->efi->efi_memdesc_size = *map->desc_size; - p->efi->efi_memdesc_version = *map->desc_ver; - efi_set_u64_split((unsigned long)*map->map, + p->efi->efi_memdesc_size = map->desc_size; + p->efi->efi_memdesc_version = map->desc_ver; + efi_set_u64_split((unsigned long)map->map, &p->efi->efi_memmap, &p->efi->efi_memmap_hi); - p->efi->efi_memmap_size = *map->map_size; + p->efi->efi_memmap_size = map->map_size; return EFI_SUCCESS; } static efi_status_t exit_boot(struct boot_params *boot_params, void *handle) { - unsigned long map_sz, key, desc_size, buff_size; - efi_memory_desc_t *mem_map; struct setup_data *e820ext = NULL; __u32 e820ext_size = 0; efi_status_t status; - __u32 desc_version; - struct efi_boot_memmap map; struct exit_boot_struct priv; - map.map = &mem_map; - map.map_size = &map_sz; - map.desc_size = &desc_size; - map.desc_ver = &desc_version; - map.key_ptr = &key; - map.buff_size = &buff_size; priv.boot_params = boot_params; priv.efi = &boot_params->efi_info; @@ -647,7 +769,7 @@ static efi_status_t exit_boot(struct boot_params *boot_params, void *handle) return status; /* Might as well exit boot services now */ - status = efi_exit_boot_services(handle, &map, &priv, exit_boot_func); + status = efi_exit_boot_services(handle, &priv, exit_boot_func); if (status != EFI_SUCCESS) return status; @@ -661,82 +783,179 @@ static efi_status_t exit_boot(struct boot_params *boot_params, void *handle) return EFI_SUCCESS; } +static bool have_unsupported_snp_features(void) +{ + u64 unsupported; + + unsupported = snp_get_unsupported_features(sev_get_status()); + if (unsupported) { + efi_err("Unsupported SEV-SNP features detected: 0x%llx\n", + unsupported); + return true; + } + return false; +} + +static void efi_get_seed(void *seed, int size) +{ + efi_get_random_bytes(size, seed); + + /* + * This only updates seed[0] when running on 32-bit, but in that case, + * seed[1] is not used anyway, as there is no virtual KASLR on 32-bit. + */ + *(unsigned long *)seed ^= kaslr_get_random_long("EFI"); +} + +static void error(char *str) +{ + efi_warn("Decompression failed: %s\n", str); +} + +static const char *cmdline_memmap_override; + +static efi_status_t parse_options(const char *cmdline) +{ + static const char opts[][14] = { + "mem=", "memmap=", "hugepages=" + }; + + for (int i = 0; i < ARRAY_SIZE(opts); i++) { + const char *p = strstr(cmdline, opts[i]); + + if (p == cmdline || (p > cmdline && isspace(p[-1]))) { + cmdline_memmap_override = opts[i]; + break; + } + } + + return efi_parse_options(cmdline); +} + +static efi_status_t efi_decompress_kernel(unsigned long *kernel_entry, + struct boot_params *boot_params) +{ + unsigned long virt_addr = LOAD_PHYSICAL_ADDR; + unsigned long addr, alloc_size, entry; + efi_status_t status; + u32 seed[2] = {}; + + boot_params_ptr = boot_params; + + /* determine the required size of the allocation */ + alloc_size = ALIGN(max_t(unsigned long, output_len, kernel_total_size), + MIN_KERNEL_ALIGN); + + if (IS_ENABLED(CONFIG_RANDOMIZE_BASE) && !efi_nokaslr) { + u64 range = KERNEL_IMAGE_SIZE - LOAD_PHYSICAL_ADDR - kernel_total_size; + static const efi_char16_t ami[] = L"American Megatrends"; + + efi_get_seed(seed, sizeof(seed)); + + virt_addr += (range * seed[1]) >> 32; + virt_addr &= ~(CONFIG_PHYSICAL_ALIGN - 1); + + /* + * Older Dell systems with AMI UEFI firmware v2.0 may hang + * while decompressing the kernel if physical address + * randomization is enabled. + * + * https://bugzilla.kernel.org/show_bug.cgi?id=218173 + */ + if (efi_system_table->hdr.revision <= EFI_2_00_SYSTEM_TABLE_REVISION && + !memcmp(efistub_fw_vendor(), ami, sizeof(ami))) { + efi_debug("AMI firmware v2.0 or older detected - disabling physical KASLR\n"); + seed[0] = 0; + } else if (cmdline_memmap_override) { + efi_info("%s detected on the kernel command line - disabling physical KASLR\n", + cmdline_memmap_override); + seed[0] = 0; + } + + boot_params->hdr.loadflags |= KASLR_FLAG; + } + + status = efi_random_alloc(alloc_size, CONFIG_PHYSICAL_ALIGN, &addr, + seed[0], EFI_LOADER_CODE, + LOAD_PHYSICAL_ADDR, + EFI_X86_KERNEL_ALLOC_LIMIT); + if (status != EFI_SUCCESS) + return status; + + entry = decompress_kernel((void *)addr, virt_addr, error); + if (entry == ULONG_MAX) { + efi_free(alloc_size, addr); + return EFI_LOAD_ERROR; + } + + *kernel_entry = addr + entry; + + return efi_adjust_memory_range_protection(addr, kernel_text_size) ?: + efi_adjust_memory_range_protection(addr + kernel_inittext_offset, + kernel_inittext_size); +} + +static void __noreturn enter_kernel(unsigned long kernel_addr, + struct boot_params *boot_params) +{ + /* enter decompressed kernel with boot_params pointer in RSI/ESI */ + asm("jmp *%0"::"r"(kernel_addr), "S"(boot_params)); + + unreachable(); +} + /* - * On success, we return the address of startup_32, which has potentially been - * relocated by efi_relocate_kernel. - * On failure, we exit to the firmware via efi_exit instead of returning. + * On success, this routine will jump to the relocated image directly and never + * return. On failure, it will exit to the firmware via efi_exit() instead of + * returning. */ -unsigned long efi_main(efi_handle_t handle, - efi_system_table_t *sys_table_arg, - struct boot_params *boot_params) +void __noreturn efi_stub_entry(efi_handle_t handle, + efi_system_table_t *sys_table_arg, + struct boot_params *boot_params) + { - unsigned long bzimage_addr = (unsigned long)startup_32; - unsigned long buffer_start, buffer_end; - struct setup_header *hdr = &boot_params->hdr; + efi_guid_t guid = EFI_MEMORY_ATTRIBUTE_PROTOCOL_GUID; + const struct linux_efi_initrd *initrd = NULL; + unsigned long kernel_entry; + struct setup_header *hdr; efi_status_t status; efi_system_table = sys_table_arg; - /* Check if we were booted by the EFI firmware */ if (efi_system_table->hdr.signature != EFI_SYSTEM_TABLE_SIGNATURE) efi_exit(handle, EFI_INVALID_PARAMETER); - /* - * If the kernel isn't already loaded at a suitable address, - * relocate it. - * - * It must be loaded above LOAD_PHYSICAL_ADDR. - * - * The maximum address for 64-bit is 1 << 46 for 4-level paging. This - * is defined as the macro MAXMEM, but unfortunately that is not a - * compile-time constant if 5-level paging is configured, so we instead - * define our own macro for use here. - * - * For 32-bit, the maximum address is complicated to figure out, for - * now use KERNEL_IMAGE_SIZE, which will be 512MiB, the same as what - * KASLR uses. - * - * Also relocate it if image_offset is zero, i.e. the kernel wasn't - * loaded by LoadImage, but rather by a bootloader that called the - * handover entry. The reason we must always relocate in this case is - * to handle the case of systemd-boot booting a unified kernel image, - * which is a PE executable that contains the bzImage and an initrd as - * COFF sections. The initrd section is placed after the bzImage - * without ensuring that there are at least init_size bytes available - * for the bzImage, and thus the compressed kernel's startup code may - * overwrite the initrd unless it is moved out of the way. - */ + if (!IS_ENABLED(CONFIG_EFI_HANDOVER_PROTOCOL) || !boot_params) { + status = efi_allocate_bootparams(handle, &boot_params); + if (status != EFI_SUCCESS) + efi_exit(handle, status); + } - buffer_start = ALIGN(bzimage_addr - image_offset, - hdr->kernel_alignment); - buffer_end = buffer_start + hdr->init_size; - - if ((buffer_start < LOAD_PHYSICAL_ADDR) || - (IS_ENABLED(CONFIG_X86_32) && buffer_end > KERNEL_IMAGE_SIZE) || - (IS_ENABLED(CONFIG_X86_64) && buffer_end > MAXMEM_X86_64_4LEVEL) || - (image_offset == 0)) { - extern char _bss[]; - - status = efi_relocate_kernel(&bzimage_addr, - (unsigned long)_bss - bzimage_addr, - hdr->init_size, - hdr->pref_address, - hdr->kernel_alignment, - LOAD_PHYSICAL_ADDR); - if (status != EFI_SUCCESS) { - efi_err("efi_relocate_kernel() failed!\n"); - goto fail; + hdr = &boot_params->hdr; + + if (have_unsupported_snp_features()) + efi_exit(handle, EFI_UNSUPPORTED); + + if (IS_ENABLED(CONFIG_EFI_DXE_MEM_ATTRIBUTES)) { + efi_dxe_table = get_efi_config_table(EFI_DXE_SERVICES_TABLE_GUID); + if (efi_dxe_table && + efi_dxe_table->hdr.signature != EFI_DXE_SERVICES_TABLE_SIGNATURE) { + efi_warn("Ignoring DXE services table: invalid signature\n"); + efi_dxe_table = NULL; } - /* - * Now that we've copied the kernel elsewhere, we no longer - * have a set up block before startup_32(), so reset image_offset - * to zero in case it was set earlier. - */ - image_offset = 0; + } + + /* grab the memory attributes protocol if it exists */ + efi_bs_call(locate_protocol, &guid, NULL, (void **)&memattr); + + status = efi_setup_5level_paging(); + if (status != EFI_SUCCESS) { + efi_err("efi_setup_5level_paging() failed!\n"); + goto fail; } #ifdef CONFIG_CMDLINE_BOOL - status = efi_parse_options(CONFIG_CMDLINE); + status = parse_options(CONFIG_CMDLINE); if (status != EFI_SUCCESS) { efi_err("Failed to parse options\n"); goto fail; @@ -745,13 +964,22 @@ unsigned long efi_main(efi_handle_t handle, if (!IS_ENABLED(CONFIG_CMDLINE_OVERRIDE)) { unsigned long cmdline_paddr = ((u64)hdr->cmd_line_ptr | ((u64)boot_params->ext_cmd_line_ptr << 32)); - status = efi_parse_options((char *)cmdline_paddr); + status = parse_options((char *)cmdline_paddr); if (status != EFI_SUCCESS) { efi_err("Failed to parse options\n"); goto fail; } } + if (efi_mem_encrypt > 0) + hdr->xloadflags |= XLF_MEM_ENCRYPTION; + + status = efi_decompress_kernel(&kernel_entry, boot_params); + if (status != EFI_SUCCESS) { + efi_err("Failed to decompress kernel\n"); + goto fail; + } + /* * At this point, an initrd may already have been loaded by the * bootloader and passed via bootparams. We permit an initrd loaded @@ -761,24 +989,18 @@ unsigned long efi_main(efi_handle_t handle, * arguments will be processed only if image is not NULL, which will be * the case only if we were loaded via the PE entry point. */ - if (!efi_noinitrd) { - unsigned long addr, size; - - status = efi_load_initrd(image, &addr, &size, - hdr->initrd_addr_max, ULONG_MAX); - - if (status != EFI_SUCCESS) { - efi_err("Failed to load initrd!\n"); - goto fail; - } - if (size > 0) { - efi_set_u64_split(addr, &hdr->ramdisk_image, - &boot_params->ext_ramdisk_image); - efi_set_u64_split(size, &hdr->ramdisk_size, - &boot_params->ext_ramdisk_size); - } + status = efi_load_initrd(image, hdr->initrd_addr_max, ULONG_MAX, + &initrd); + if (status != EFI_SUCCESS) + goto fail; + if (initrd && initrd->size > 0) { + efi_set_u64_split(initrd->base, &hdr->ramdisk_image, + &boot_params->ext_ramdisk_image); + efi_set_u64_split(initrd->size, &hdr->ramdisk_size, + &boot_params->ext_ramdisk_size); } + /* * If the boot loader gave us a value for secure_boot then we use that, * otherwise we ask the BIOS. @@ -791,7 +1013,7 @@ unsigned long efi_main(efi_handle_t handle, efi_random_get_seed(); - efi_retrieve_tpm2_eventlog(); + efi_retrieve_eventlog(); setup_graphics(boot_params); @@ -799,15 +1021,50 @@ unsigned long efi_main(efi_handle_t handle, setup_quirks(boot_params); + setup_unaccepted_memory(); + status = exit_boot(boot_params, handle); if (status != EFI_SUCCESS) { efi_err("exit_boot() failed!\n"); goto fail; } - return bzimage_addr; + /* + * Call the SEV init code while still running with the firmware's + * GDT/IDT, so #VC exceptions will be handled by EFI. + */ + sev_enable(boot_params); + + efi_5level_switch(); + + enter_kernel(kernel_entry, boot_params); fail: - efi_err("efi_main() failed!\n"); + efi_err("efi_stub_entry() failed!\n"); efi_exit(handle, status); } + +efi_status_t __efiapi efi_pe_entry(efi_handle_t handle, + efi_system_table_t *sys_table_arg) +{ + efi_stub_entry(handle, sys_table_arg, NULL); +} + +#ifdef CONFIG_EFI_HANDOVER_PROTOCOL +void efi_handover_entry(efi_handle_t handle, efi_system_table_t *sys_table_arg, + struct boot_params *boot_params) +{ + memset(_bss, 0, _ebss - _bss); + efi_stub_entry(handle, sys_table_arg, boot_params); +} + +#ifndef CONFIG_EFI_MIXED +extern __alias(efi_handover_entry) +void efi32_stub_entry(efi_handle_t handle, efi_system_table_t *sys_table_arg, + struct boot_params *boot_params); + +extern __alias(efi_handover_entry) +void efi64_stub_entry(efi_handle_t handle, efi_system_table_t *sys_table_arg, + struct boot_params *boot_params); +#endif +#endif |
