From 0d95981438c3bdb53cc99b0fb656d24d7a80e1f3 Mon Sep 17 00:00:00 2001 From: Dominik Brodowski Date: Wed, 6 Nov 2019 08:06:13 +0100 Subject: [PATCH] x86: efi/random: Invoke EFI_RNG_PROTOCOL to seed the UEFI RNG table Invoke the EFI_RNG_PROTOCOL protocol in the context of the x86 EFI stub, same as is done on arm/arm64 since commit 568bc4e87033 ("efi/arm*/libstub: Invoke EFI_RNG_PROTOCOL to seed the UEFI RNG table"). Within the stub, a Linux-specific RNG seed UEFI config table will be seeded. The EFI routines in the core kernel will pick that up later, yet still early during boot, to seed the kernel entropy pool. If CONFIG_RANDOM_TRUST_BOOTLOADER, entropy is credited for this seed. Signed-off-by: Dominik Brodowski Signed-off-by: Ard Biesheuvel --- arch/x86/boot/compressed/eboot.c | 3 +++ drivers/firmware/efi/libstub/Makefile | 5 +++-- drivers/firmware/efi/libstub/efistub.h | 2 -- include/linux/efi.h | 2 ++ 4 files changed, 8 insertions(+), 4 deletions(-) diff --git a/arch/x86/boot/compressed/eboot.c b/arch/x86/boot/compressed/eboot.c index 82bc60c8acb24..68945c5700bf8 100644 --- a/arch/x86/boot/compressed/eboot.c +++ b/arch/x86/boot/compressed/eboot.c @@ -782,6 +782,9 @@ efi_main(struct efi_config *c, struct boot_params *boot_params) /* Ask the firmware to clear memory on unclean shutdown */ efi_enable_reset_attack_mitigation(sys_table); + + efi_random_get_seed(sys_table); + efi_retrieve_tpm2_eventlog(sys_table); setup_graphics(boot_params); diff --git a/drivers/firmware/efi/libstub/Makefile b/drivers/firmware/efi/libstub/Makefile index ee0661ddb25bb..c35f893897e14 100644 --- a/drivers/firmware/efi/libstub/Makefile +++ b/drivers/firmware/efi/libstub/Makefile @@ -38,7 +38,8 @@ OBJECT_FILES_NON_STANDARD := y # Prevents link failures: __sanitizer_cov_trace_pc() is not linked in. KCOV_INSTRUMENT := n -lib-y := efi-stub-helper.o gop.o secureboot.o tpm.o +lib-y := efi-stub-helper.o gop.o secureboot.o tpm.o \ + random.o # include the stub's generic dependencies from lib/ when building for ARM/arm64 arm-deps-y := fdt_rw.c fdt_ro.c fdt_wip.c fdt.c fdt_empty_tree.c fdt_sw.c @@ -47,7 +48,7 @@ arm-deps-$(CONFIG_ARM64) += sort.c $(obj)/lib-%.o: $(srctree)/lib/%.c FORCE $(call if_changed_rule,cc_o_c) -lib-$(CONFIG_EFI_ARMSTUB) += arm-stub.o fdt.o string.o random.o \ +lib-$(CONFIG_EFI_ARMSTUB) += arm-stub.o fdt.o string.o \ $(patsubst %.c,lib-%.o,$(arm-deps-y)) lib-$(CONFIG_ARM) += arm32-stub.o diff --git a/drivers/firmware/efi/libstub/efistub.h b/drivers/firmware/efi/libstub/efistub.h index 7f1556fd867df..05739ae013c82 100644 --- a/drivers/firmware/efi/libstub/efistub.h +++ b/drivers/firmware/efi/libstub/efistub.h @@ -63,8 +63,6 @@ efi_status_t efi_random_alloc(efi_system_table_t *sys_table_arg, efi_status_t check_platform_features(efi_system_table_t *sys_table_arg); -efi_status_t efi_random_get_seed(efi_system_table_t *sys_table_arg); - void *get_efi_config_table(efi_system_table_t *sys_table, efi_guid_t guid); /* Helper macros for the usual case of using simple C variables: */ diff --git a/include/linux/efi.h b/include/linux/efi.h index d87acf62958e2..028efa7a9f3bc 100644 --- a/include/linux/efi.h +++ b/include/linux/efi.h @@ -1645,6 +1645,8 @@ static inline void efi_enable_reset_attack_mitigation(efi_system_table_t *sys_table_arg) { } #endif +efi_status_t efi_random_get_seed(efi_system_table_t *sys_table_arg); + void efi_retrieve_tpm2_eventlog(efi_system_table_t *sys_table); /* -- 2.30.2