This is a note to let you know that I've just added the patch titled efi: libstub: use EFI_LOADER_CODE region when moving the kernel in memory to the 6.1-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: efi-libstub-use-efi_loader_code-region-when-moving-the-kernel-in-memory.patch and it can be found in the queue-6.1 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From 9cf42bca30e98a1c6c9e8abf876940a551eaa3d1 Mon Sep 17 00:00:00 2001 From: Ard Biesheuvel <ardb@xxxxxxxxxx> Date: Tue, 2 Aug 2022 11:00:16 +0200 Subject: efi: libstub: use EFI_LOADER_CODE region when moving the kernel in memory From: Ard Biesheuvel <ardb@xxxxxxxxxx> commit 9cf42bca30e98a1c6c9e8abf876940a551eaa3d1 upstream. The EFI spec is not very clear about which permissions are being given when allocating pages of a certain type. However, it is quite obvious that EFI_LOADER_CODE is more likely to permit execution than EFI_LOADER_DATA, which becomes relevant once we permit booting the kernel proper with the firmware's 1:1 mapping still active. Ostensibly, recent systems such as the Surface Pro X grant executable permissions to EFI_LOADER_CODE regions but not EFI_LOADER_DATA regions. Signed-off-by: Ard Biesheuvel <ardb@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/firmware/efi/libstub/alignedmem.c | 5 +++-- drivers/firmware/efi/libstub/arm64-stub.c | 6 ++++-- drivers/firmware/efi/libstub/efistub.h | 6 ++++-- drivers/firmware/efi/libstub/mem.c | 3 ++- drivers/firmware/efi/libstub/randomalloc.c | 5 +++-- 5 files changed, 16 insertions(+), 9 deletions(-) --- a/drivers/firmware/efi/libstub/alignedmem.c +++ b/drivers/firmware/efi/libstub/alignedmem.c @@ -22,7 +22,8 @@ * Return: status code */ efi_status_t efi_allocate_pages_aligned(unsigned long size, unsigned long *addr, - unsigned long max, unsigned long align) + unsigned long max, unsigned long align, + int memory_type) { efi_physical_addr_t alloc_addr; efi_status_t status; @@ -36,7 +37,7 @@ efi_status_t efi_allocate_pages_aligned( slack = align / EFI_PAGE_SIZE - 1; status = efi_bs_call(allocate_pages, EFI_ALLOCATE_MAX_ADDRESS, - EFI_LOADER_DATA, size / EFI_PAGE_SIZE + slack, + memory_type, size / EFI_PAGE_SIZE + slack, &alloc_addr); if (status != EFI_SUCCESS) return status; --- a/drivers/firmware/efi/libstub/arm64-stub.c +++ b/drivers/firmware/efi/libstub/arm64-stub.c @@ -180,7 +180,8 @@ efi_status_t handle_kernel_image(unsigne * locate the kernel at a randomized offset in physical memory. */ status = efi_random_alloc(*reserve_size, min_kimg_align, - reserve_addr, phys_seed); + reserve_addr, phys_seed, + EFI_LOADER_CODE); if (status != EFI_SUCCESS) efi_warn("efi_random_alloc() failed: 0x%lx\n", status); } else { @@ -201,7 +202,8 @@ efi_status_t handle_kernel_image(unsigne } status = efi_allocate_pages_aligned(*reserve_size, reserve_addr, - ULONG_MAX, min_kimg_align); + ULONG_MAX, min_kimg_align, + EFI_LOADER_CODE); if (status != EFI_SUCCESS) { efi_err("Failed to relocate kernel\n"); --- a/drivers/firmware/efi/libstub/efistub.h +++ b/drivers/firmware/efi/libstub/efistub.h @@ -880,7 +880,8 @@ void efi_get_virtmap(efi_memory_desc_t * efi_status_t efi_get_random_bytes(unsigned long size, u8 *out); efi_status_t efi_random_alloc(unsigned long size, unsigned long align, - unsigned long *addr, unsigned long random_seed); + unsigned long *addr, unsigned long random_seed, + int memory_type); efi_status_t efi_random_get_seed(void); @@ -907,7 +908,8 @@ efi_status_t efi_allocate_pages(unsigned unsigned long max); efi_status_t efi_allocate_pages_aligned(unsigned long size, unsigned long *addr, - unsigned long max, unsigned long align); + unsigned long max, unsigned long align, + int memory_type); efi_status_t efi_low_alloc_above(unsigned long size, unsigned long align, unsigned long *addr, unsigned long min); --- a/drivers/firmware/efi/libstub/mem.c +++ b/drivers/firmware/efi/libstub/mem.c @@ -91,7 +91,8 @@ efi_status_t efi_allocate_pages(unsigned if (EFI_ALLOC_ALIGN > EFI_PAGE_SIZE) return efi_allocate_pages_aligned(size, addr, max, - EFI_ALLOC_ALIGN); + EFI_ALLOC_ALIGN, + EFI_LOADER_DATA); alloc_addr = ALIGN_DOWN(max + 1, EFI_ALLOC_ALIGN) - 1; status = efi_bs_call(allocate_pages, EFI_ALLOCATE_MAX_ADDRESS, --- a/drivers/firmware/efi/libstub/randomalloc.c +++ b/drivers/firmware/efi/libstub/randomalloc.c @@ -53,7 +53,8 @@ static unsigned long get_entry_num_slots efi_status_t efi_random_alloc(unsigned long size, unsigned long align, unsigned long *addr, - unsigned long random_seed) + unsigned long random_seed, + int memory_type) { unsigned long total_slots = 0, target_slot; unsigned long total_mirrored_slots = 0; @@ -118,7 +119,7 @@ efi_status_t efi_random_alloc(unsigned l pages = size / EFI_PAGE_SIZE; status = efi_bs_call(allocate_pages, EFI_ALLOCATE_ADDRESS, - EFI_LOADER_DATA, pages, &target); + memory_type, pages, &target); if (status == EFI_SUCCESS) *addr = target; break; Patches currently in stable-queue which might be from ardb@xxxxxxxxxx are queue-6.1/x86-boot-compressed-avoid-touching-ecx-in-startup32_set_idt_entry.patch queue-6.1/x86-boot-compressed-only-build-mem_encrypt.s-if-amd_mem_encrypt-y.patch queue-6.1/efi-capsule-loader-fix-incorrect-allocation-size.patch queue-6.1/x86-decompressor-move-global-symbol-references-to-c-code.patch queue-6.1/x86-boot-compressed-move-startup32_load_idt-into-.text-section.patch queue-6.1/x86-decompressor-only-call-the-trampoline-when-changing-paging-levels.patch queue-6.1/x86-boot-compressed-rename-efi_thunk_64.s-to-efi-mixed.s.patch queue-6.1/x86-decompressor-merge-trampoline-cleanup-with-switching-code.patch queue-6.1/x86-boot-compressed-move-efi32_pe_entry-out-of-head_64.s.patch queue-6.1/efi-verify-that-variable-services-are-supported.patch queue-6.1/x86-decompressor-call-trampoline-directly-from-c-code.patch queue-6.1/x86-boot-compressed-pull-global-variable-reference-into-startup32_load_idt.patch queue-6.1/x86-boot-compressed-simplify-idt-gdt-preserve-restore-in-the-efi-thunk.patch queue-6.1/x86-decompressor-assign-paging-related-global-variables-earlier.patch queue-6.1/x86-boot-compressed-move-32-bit-entrypoint-code-into-.text-section.patch queue-6.1/x86-boot-compressed-move-efi32_pe_entry-into-.text-section.patch queue-6.1/x86-decompressor-avoid-the-need-for-a-stack-in-the-32-bit-trampoline.patch queue-6.1/x86-boot-compressed-move-startup32_check_sev_cbit-out-of-head_64.s.patch queue-6.1/x86-boot-compressed-efi-merge-multiple-definitions-of-image_offset-into-one.patch queue-6.1/x86-boot-compressed-move-startup32_load_idt-out-of-head_64.s.patch queue-6.1/decompress-use-8-byte-alignment.patch queue-6.1/x86-boot-compressed-move-efi32_entry-out-of-head_64.s.patch queue-6.1/efi-libstub-use-efi_loader_code-region-when-moving-the-kernel-in-memory.patch queue-6.1/crypto-arm64-neonbs-fix-out-of-bounds-access-on-short-input.patch queue-6.1/x86-boot-compressed-move-bootargs-parsing-out-of-32-bit-startup-code.patch queue-6.1/efivarfs-request-at-most-512-bytes-for-variable-names.patch queue-6.1/x86-boot-compressed-adhere-to-calling-convention-in-get_sev_encryption_bit.patch queue-6.1/x86-boot-compressed-move-startup32_check_sev_cbit-into-.text.patch queue-6.1/x86-decompressor-store-boot_params-pointer-in-callee-save-register.patch queue-6.1/x86-efistub-branch-straight-to-kernel-entry-point-from-c-code.patch queue-6.1/x86-decompressor-call-trampoline-as-a-normal-function.patch queue-6.1/x86-decompressor-pass-pgtable-address-to-trampoline-directly.patch queue-6.1/x86-decompressor-use-standard-calling-convention-for-trampoline.patch queue-6.1/x86-efi-make-the-deprecated-efi-handover-protocol-optional.patch