[GIT PULL] EFI fixes

From: Ingo Molnar
Date: Fri Nov 01 2019 - 13:43:08 EST


Linus,

Please pull the latest efi-urgent-for-linus git tree from:

git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git efi-urgent-for-linus

# HEAD: 359efcc2c910117d2faf704ce154e91fc976d37f efi/efi_test: Lock down /dev/efi_test and require CAP_SYS_ADMIN

Various fixes all over the map: prevent boot crashes on HyperV, classify
UEFI randomness as bootloader randomness, fix EFI boot for the Raspberry
Pi2, fix efi_test permissions, etc.


Thanks,

Ingo

------------------>
Ard Biesheuvel (1):
efi: libstub/arm: Account for firmware reserved memory at the base of RAM

Dominik Brodowski (1):
efi/random: Treat EFI_RNG_PROTOCOL output as bootloader randomness

Javier Martinez Canillas (1):
efi/efi_test: Lock down /dev/efi_test and require CAP_SYS_ADMIN

Jerry Snitselaar (1):
efi/tpm: Return -EINVAL when determining tpm final events log size fails

Kairui Song (1):
x86, efi: Never relocate kernel below lowest acceptable address

Narendra K (1):
efi: Make CONFIG_EFI_RCI2_TABLE selectable on x86 only


arch/x86/boot/compressed/eboot.c | 4 +++-
drivers/firmware/efi/Kconfig | 1 +
drivers/firmware/efi/efi.c | 2 +-
drivers/firmware/efi/libstub/Makefile | 1 +
drivers/firmware/efi/libstub/arm32-stub.c | 16 +++++++++++++---
drivers/firmware/efi/libstub/efi-stub-helper.c | 24 ++++++++++--------------
drivers/firmware/efi/test/efi_test.c | 8 ++++++++
drivers/firmware/efi/tpm.c | 1 +
include/linux/efi.h | 18 ++++++++++++++++--
include/linux/security.h | 1 +
security/lockdown/lockdown.c | 1 +
11 files changed, 56 insertions(+), 21 deletions(-)

diff --git a/arch/x86/boot/compressed/eboot.c b/arch/x86/boot/compressed/eboot.c
index d6662fdef300..82bc60c8acb2 100644
--- a/arch/x86/boot/compressed/eboot.c
+++ b/arch/x86/boot/compressed/eboot.c
@@ -13,6 +13,7 @@
#include <asm/e820/types.h>
#include <asm/setup.h>
#include <asm/desc.h>
+#include <asm/boot.h>

#include "../string.h"
#include "eboot.h"
@@ -813,7 +814,8 @@ efi_main(struct efi_config *c, struct boot_params *boot_params)
status = efi_relocate_kernel(sys_table, &bzimage_addr,
hdr->init_size, hdr->init_size,
hdr->pref_address,
- hdr->kernel_alignment);
+ hdr->kernel_alignment,
+ LOAD_PHYSICAL_ADDR);
if (status != EFI_SUCCESS) {
efi_printk(sys_table, "efi_relocate_kernel() failed!\n");
goto fail;
diff --git a/drivers/firmware/efi/Kconfig b/drivers/firmware/efi/Kconfig
index 178ee8106828..b248870a9806 100644
--- a/drivers/firmware/efi/Kconfig
+++ b/drivers/firmware/efi/Kconfig
@@ -182,6 +182,7 @@ config RESET_ATTACK_MITIGATION

config EFI_RCI2_TABLE
bool "EFI Runtime Configuration Interface Table Version 2 Support"
+ depends on X86 || COMPILE_TEST
help
Displays the content of the Runtime Configuration Interface
Table version 2 on Dell EMC PowerEdge systems as a binary
diff --git a/drivers/firmware/efi/efi.c b/drivers/firmware/efi/efi.c
index 69f00f7453a3..e98bbf8e56d9 100644
--- a/drivers/firmware/efi/efi.c
+++ b/drivers/firmware/efi/efi.c
@@ -554,7 +554,7 @@ int __init efi_config_parse_tables(void *config_tables, int count, int sz,
sizeof(*seed) + size);
if (seed != NULL) {
pr_notice("seeding entropy pool\n");
- add_device_randomness(seed->bits, seed->size);
+ add_bootloader_randomness(seed->bits, seed->size);
early_memunmap(seed, sizeof(*seed) + size);
} else {
pr_err("Could not map UEFI random seed!\n");
diff --git a/drivers/firmware/efi/libstub/Makefile b/drivers/firmware/efi/libstub/Makefile
index 0460c7581220..ee0661ddb25b 100644
--- a/drivers/firmware/efi/libstub/Makefile
+++ b/drivers/firmware/efi/libstub/Makefile
@@ -52,6 +52,7 @@ lib-$(CONFIG_EFI_ARMSTUB) += arm-stub.o fdt.o string.o random.o \

lib-$(CONFIG_ARM) += arm32-stub.o
lib-$(CONFIG_ARM64) += arm64-stub.o
+CFLAGS_arm32-stub.o := -DTEXT_OFFSET=$(TEXT_OFFSET)
CFLAGS_arm64-stub.o := -DTEXT_OFFSET=$(TEXT_OFFSET)

#
diff --git a/drivers/firmware/efi/libstub/arm32-stub.c b/drivers/firmware/efi/libstub/arm32-stub.c
index e8f7aefb6813..41213bf5fcf5 100644
--- a/drivers/firmware/efi/libstub/arm32-stub.c
+++ b/drivers/firmware/efi/libstub/arm32-stub.c
@@ -195,6 +195,7 @@ efi_status_t handle_kernel_image(efi_system_table_t *sys_table,
unsigned long dram_base,
efi_loaded_image_t *image)
{
+ unsigned long kernel_base;
efi_status_t status;

/*
@@ -204,9 +205,18 @@ efi_status_t handle_kernel_image(efi_system_table_t *sys_table,
* loaded. These assumptions are made by the decompressor,
* before any memory map is available.
*/
- dram_base = round_up(dram_base, SZ_128M);
+ kernel_base = round_up(dram_base, SZ_128M);

- status = reserve_kernel_base(sys_table, dram_base, reserve_addr,
+ /*
+ * Note that some platforms (notably, the Raspberry Pi 2) put
+ * spin-tables and other pieces of firmware at the base of RAM,
+ * abusing the fact that the window of TEXT_OFFSET bytes at the
+ * base of the kernel image is only partially used at the moment.
+ * (Up to 5 pages are used for the swapper page tables)
+ */
+ kernel_base += TEXT_OFFSET - 5 * PAGE_SIZE;
+
+ status = reserve_kernel_base(sys_table, kernel_base, reserve_addr,
reserve_size);
if (status != EFI_SUCCESS) {
pr_efi_err(sys_table, "Unable to allocate memory for uncompressed kernel.\n");
@@ -220,7 +230,7 @@ efi_status_t handle_kernel_image(efi_system_table_t *sys_table,
*image_size = image->image_size;
status = efi_relocate_kernel(sys_table, image_addr, *image_size,
*image_size,
- dram_base + MAX_UNCOMP_KERNEL_SIZE, 0);
+ kernel_base + MAX_UNCOMP_KERNEL_SIZE, 0, 0);
if (status != EFI_SUCCESS) {
pr_efi_err(sys_table, "Failed to relocate kernel.\n");
efi_free(sys_table, *reserve_size, *reserve_addr);
diff --git a/drivers/firmware/efi/libstub/efi-stub-helper.c b/drivers/firmware/efi/libstub/efi-stub-helper.c
index 3caae7f2cf56..35dbc2791c97 100644
--- a/drivers/firmware/efi/libstub/efi-stub-helper.c
+++ b/drivers/firmware/efi/libstub/efi-stub-helper.c
@@ -260,11 +260,11 @@ efi_status_t efi_high_alloc(efi_system_table_t *sys_table_arg,
}

/*
- * Allocate at the lowest possible address.
+ * Allocate at the lowest possible address that is not below 'min'.
*/
-efi_status_t efi_low_alloc(efi_system_table_t *sys_table_arg,
- unsigned long size, unsigned long align,
- unsigned long *addr)
+efi_status_t efi_low_alloc_above(efi_system_table_t *sys_table_arg,
+ unsigned long size, unsigned long align,
+ unsigned long *addr, unsigned long min)
{
unsigned long map_size, desc_size, buff_size;
efi_memory_desc_t *map;
@@ -311,13 +311,8 @@ efi_status_t efi_low_alloc(efi_system_table_t *sys_table_arg,
start = desc->phys_addr;
end = start + desc->num_pages * EFI_PAGE_SIZE;

- /*
- * Don't allocate at 0x0. It will confuse code that
- * checks pointers against NULL. Skip the first 8
- * bytes so we start at a nice even number.
- */
- if (start == 0x0)
- start += 8;
+ if (start < min)
+ start = min;

start = round_up(start, align);
if ((start + size) > end)
@@ -698,7 +693,8 @@ efi_status_t efi_relocate_kernel(efi_system_table_t *sys_table_arg,
unsigned long image_size,
unsigned long alloc_size,
unsigned long preferred_addr,
- unsigned long alignment)
+ unsigned long alignment,
+ unsigned long min_addr)
{
unsigned long cur_image_addr;
unsigned long new_addr = 0;
@@ -731,8 +727,8 @@ efi_status_t efi_relocate_kernel(efi_system_table_t *sys_table_arg,
* possible.
*/
if (status != EFI_SUCCESS) {
- status = efi_low_alloc(sys_table_arg, alloc_size, alignment,
- &new_addr);
+ status = efi_low_alloc_above(sys_table_arg, alloc_size,
+ alignment, &new_addr, min_addr);
}
if (status != EFI_SUCCESS) {
pr_efi_err(sys_table_arg, "Failed to allocate usable memory for kernel.\n");
diff --git a/drivers/firmware/efi/test/efi_test.c b/drivers/firmware/efi/test/efi_test.c
index 877745c3aaf2..7baf48c01e72 100644
--- a/drivers/firmware/efi/test/efi_test.c
+++ b/drivers/firmware/efi/test/efi_test.c
@@ -14,6 +14,7 @@
#include <linux/init.h>
#include <linux/proc_fs.h>
#include <linux/efi.h>
+#include <linux/security.h>
#include <linux/slab.h>
#include <linux/uaccess.h>

@@ -717,6 +718,13 @@ static long efi_test_ioctl(struct file *file, unsigned int cmd,

static int efi_test_open(struct inode *inode, struct file *file)
{
+ int ret = security_locked_down(LOCKDOWN_EFI_TEST);
+
+ if (ret)
+ return ret;
+
+ if (!capable(CAP_SYS_ADMIN))
+ return -EACCES;
/*
* nothing special to do here
* We do accept multiple open files at the same time as we
diff --git a/drivers/firmware/efi/tpm.c b/drivers/firmware/efi/tpm.c
index ebd7977653a8..31f9f0e369b9 100644
--- a/drivers/firmware/efi/tpm.c
+++ b/drivers/firmware/efi/tpm.c
@@ -88,6 +88,7 @@ int __init efi_tpm_eventlog_init(void)

if (tbl_size < 0) {
pr_err(FW_BUG "Failed to parse event in TPM Final Events Log\n");
+ ret = -EINVAL;
goto out_calc;
}

diff --git a/include/linux/efi.h b/include/linux/efi.h
index bd3837022307..d87acf62958e 100644
--- a/include/linux/efi.h
+++ b/include/linux/efi.h
@@ -1579,9 +1579,22 @@ char *efi_convert_cmdline(efi_system_table_t *sys_table_arg,
efi_status_t efi_get_memory_map(efi_system_table_t *sys_table_arg,
struct efi_boot_memmap *map);

+efi_status_t efi_low_alloc_above(efi_system_table_t *sys_table_arg,
+ unsigned long size, unsigned long align,
+ unsigned long *addr, unsigned long min);
+
+static inline
efi_status_t efi_low_alloc(efi_system_table_t *sys_table_arg,
unsigned long size, unsigned long align,
- unsigned long *addr);
+ unsigned long *addr)
+{
+ /*
+ * Don't allocate at 0x0. It will confuse code that
+ * checks pointers against NULL. Skip the first 8
+ * bytes so we start at a nice even number.
+ */
+ return efi_low_alloc_above(sys_table_arg, size, align, addr, 0x8);
+}

efi_status_t efi_high_alloc(efi_system_table_t *sys_table_arg,
unsigned long size, unsigned long align,
@@ -1592,7 +1605,8 @@ efi_status_t efi_relocate_kernel(efi_system_table_t *sys_table_arg,
unsigned long image_size,
unsigned long alloc_size,
unsigned long preferred_addr,
- unsigned long alignment);
+ unsigned long alignment,
+ unsigned long min_addr);

efi_status_t handle_cmdline_files(efi_system_table_t *sys_table_arg,
efi_loaded_image_t *image,
diff --git a/include/linux/security.h b/include/linux/security.h
index a8d59d612d27..9df7547afc0c 100644
--- a/include/linux/security.h
+++ b/include/linux/security.h
@@ -105,6 +105,7 @@ enum lockdown_reason {
LOCKDOWN_NONE,
LOCKDOWN_MODULE_SIGNATURE,
LOCKDOWN_DEV_MEM,
+ LOCKDOWN_EFI_TEST,
LOCKDOWN_KEXEC,
LOCKDOWN_HIBERNATION,
LOCKDOWN_PCI_ACCESS,
diff --git a/security/lockdown/lockdown.c b/security/lockdown/lockdown.c
index 8a10b43daf74..40b790536def 100644
--- a/security/lockdown/lockdown.c
+++ b/security/lockdown/lockdown.c
@@ -20,6 +20,7 @@ static const char *const lockdown_reasons[LOCKDOWN_CONFIDENTIALITY_MAX+1] = {
[LOCKDOWN_NONE] = "none",
[LOCKDOWN_MODULE_SIGNATURE] = "unsigned module loading",
[LOCKDOWN_DEV_MEM] = "/dev/mem,kmem,port",
+ [LOCKDOWN_EFI_TEST] = "/dev/efi_test access",
[LOCKDOWN_KEXEC] = "kexec of unsigned images",
[LOCKDOWN_HIBERNATION] = "hibernation",
[LOCKDOWN_PCI_ACCESS] = "direct PCI access",