diff options
| -rw-r--r-- | drivers/firmware/efi/libstub/arm64-stub.c | 12 | ||||
| -rw-r--r-- | include/linux/efi.h | 11 |
2 files changed, 20 insertions, 3 deletions
diff --git a/drivers/firmware/efi/libstub/arm64-stub.c b/drivers/firmware/efi/libstub/arm64-stub.c index 00c91a3807ea..577173ee1f83 100644 --- a/drivers/firmware/efi/libstub/arm64-stub.c +++ b/drivers/firmware/efi/libstub/arm64-stub.c @@ -101,7 +101,15 @@ efi_status_t handle_kernel_image(unsigned long *image_addr, u64 min_kimg_align = efi_nokaslr ? MIN_KIMG_ALIGN : EFI_KIMG_ALIGN; if (IS_ENABLED(CONFIG_RANDOMIZE_BASE)) { - if (!efi_nokaslr) { + efi_guid_t li_fixed_proto = LINUX_EFI_LOADED_IMAGE_FIXED_GUID; + void *p; + + if (efi_nokaslr) { + efi_info("KASLR disabled on kernel command line\n"); + } else if (efi_bs_call(handle_protocol, image_handle, + &li_fixed_proto, &p) == EFI_SUCCESS) { + efi_info("Image placement fixed by loader\n"); + } else { status = efi_get_random_bytes(sizeof(phys_seed), (u8 *)&phys_seed); if (status == EFI_NOT_FOUND) { @@ -112,8 +120,6 @@ efi_status_t handle_kernel_image(unsigned long *image_addr, status); efi_nokaslr = true; } - } else { - efi_info("KASLR disabled on kernel command line\n"); } } diff --git a/include/linux/efi.h b/include/linux/efi.h index b1f7c6a3e5bf..580ce607d6f5 100644 --- a/include/linux/efi.h +++ b/include/linux/efi.h @@ -410,6 +410,17 @@ void efi_native_runtime_setup(void); #define LINUX_EFI_MOK_VARIABLE_TABLE_GUID EFI_GUID(0xc451ed2b, 0x9694, 0x45d3, 0xba, 0xba, 0xed, 0x9f, 0x89, 0x88, 0xa3, 0x89) #define LINUX_EFI_COCO_SECRET_AREA_GUID EFI_GUID(0xadf956ad, 0xe98c, 0x484c, 0xae, 0x11, 0xb5, 0x1c, 0x7d, 0x33, 0x64, 0x47) +/* + * This GUID may be installed onto the kernel image's handle as a NULL protocol + * to signal to the stub that the placement of the image should be respected, + * and moving the image in physical memory is undesirable. To ensure + * compatibility with 64k pages kernels with virtually mapped stacks, and to + * avoid defeating physical randomization, this protocol should only be + * installed if the image was placed at a randomized 128k aligned address in + * memory. + */ +#define LINUX_EFI_LOADED_IMAGE_FIXED_GUID EFI_GUID(0xf5a37b6d, 0x3344, 0x42a5, 0xb6, 0xbb, 0x97, 0x86, 0x48, 0xc1, 0x89, 0x0a) + /* OEM GUIDs */ #define DELLEMC_EFI_RCI2_TABLE_GUID EFI_GUID(0x2d9f28a2, 0xa886, 0x456a, 0x97, 0xa8, 0xf1, 0x1e, 0xf2, 0x4f, 0xf4, 0x55) #define AMD_SEV_MEM_ENCRYPT_GUID EFI_GUID(0x0cf29b71, 0x9e51, 0x433a, 0xa3, 0xb7, 0x81, 0xf3, 0xab, 0x16, 0xb8, 0x75) |