diff options
| author | Ard Biesheuvel <ardb@kernel.org> | 2022-03-19 19:00:20 +0100 |
|---|---|---|
| committer | Ard Biesheuvel <ardb@kernel.org> | 2022-05-03 15:31:29 +0200 |
| commit | 07768c55f9c2ad64ccae3ed82447a87d8af8a687 (patch) | |
| tree | 4677361def98960c003906ecb45ec84947e757b0 /drivers/firmware | |
| parent | 416a9f84a77cf826fed1bf9a1908b2d066c17430 (diff) | |
efi/arm64: libstub: run image in place if randomized by the loader
If the loader has already placed the EFI kernel image randomly in
physical memory, and indicates having done so by installing the 'fixed
placement' protocol onto the image handle, don't bother randomizing the
placement again in the EFI stub.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Diffstat (limited to 'drivers/firmware')
| -rw-r--r-- | drivers/firmware/efi/libstub/arm64-stub.c | 12 |
1 files changed, 9 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"); } } |