leandrof/linux
1
0
Fork 0
forked from Minki/linux
Code Issues Pull Requests Packages Projects Releases Wiki Activity

arm64: Add ARM_SMCCC_ARCH_WORKAROUND_1 BP hardening support

Browse Source 
Add the detection and runtime code for ARM_SMCCC_ARCH_WORKAROUND_1.
It is lovely. Really.

Tested-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
This commit is contained in:
Marc Zyngier 2018-02-06 17:56:20 +00:00 committed by Catalin Marinas
parent f2d3b2e875
commit b092201e00
2 changed files with 87 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

20
arch/arm64/kernel/bpi.S
View File

@ -17,6 +17,7 @@
*/
#include <linux/linkage.h>
#include <linux/arm-smccc.h>
.macro ventry target
.rept 31
@ -85,3 +86,22 @@ ENTRY(__qcom_hyp_sanitize_link_stack_start)
.endr
ldp x29, x30, [sp], #16
ENTRY(__qcom_hyp_sanitize_link_stack_end)
.macro smccc_workaround_1 inst
sub sp, sp, #(8 * 4)
stp x2, x3, [sp, #(8 * 0)]
stp x0, x1, [sp, #(8 * 2)]
mov w0, #ARM_SMCCC_ARCH_WORKAROUND_1
\inst #0
ldp x2, x3, [sp, #(8 * 0)]
ldp x0, x1, [sp, #(8 * 2)]
add sp, sp, #(8 * 4)
.endm
ENTRY(__smccc_workaround_1_smc_start)
smccc_workaround_1 smc
ENTRY(__smccc_workaround_1_smc_end)
ENTRY(__smccc_workaround_1_hvc_start)
smccc_workaround_1 hvc
ENTRY(__smccc_workaround_1_hvc_end)

68
arch/arm64/kernel/cpu_errata.c
View File

@ -70,6 +70,10 @@ DEFINE_PER_CPU_READ_MOSTLY(struct bp_hardening_data, bp_hardening_data);
extern char __psci_hyp_bp_inval_start[], __psci_hyp_bp_inval_end[];
extern char __qcom_hyp_sanitize_link_stack_start[];
extern char __qcom_hyp_sanitize_link_stack_end[];
extern char __smccc_workaround_1_smc_start[];
extern char __smccc_workaround_1_smc_end[];
extern char __smccc_workaround_1_hvc_start[];
extern char __smccc_workaround_1_hvc_end[];
static void __copy_hyp_vect_bpi(int slot, const char *hyp_vecs_start,
const char *hyp_vecs_end)
@ -116,6 +120,10 @@ static void __install_bp_hardening_cb(bp_hardening_cb_t fn,
#define __psci_hyp_bp_inval_end NULL
#define __qcom_hyp_sanitize_link_stack_start NULL
#define __qcom_hyp_sanitize_link_stack_end NULL
#define __smccc_workaround_1_smc_start NULL
#define __smccc_workaround_1_smc_end NULL
#define __smccc_workaround_1_hvc_start NULL
#define __smccc_workaround_1_hvc_end NULL
static void __install_bp_hardening_cb(bp_hardening_cb_t fn,
const char *hyp_vecs_start,
@ -142,17 +150,75 @@ static void install_bp_hardening_cb(const struct arm64_cpu_capabilities *entry,
__install_bp_hardening_cb(fn, hyp_vecs_start, hyp_vecs_end);
}
#include <uapi/linux/psci.h>
#include <linux/arm-smccc.h>
#include <linux/psci.h>
static void call_smc_arch_workaround_1(void)
{
arm_smccc_1_1_smc(ARM_SMCCC_ARCH_WORKAROUND_1, NULL);
}
static void call_hvc_arch_workaround_1(void)
{
arm_smccc_1_1_hvc(ARM_SMCCC_ARCH_WORKAROUND_1, NULL);
}
static bool check_smccc_arch_workaround_1(const struct arm64_cpu_capabilities *entry)
{
bp_hardening_cb_t cb;
void *smccc_start, *smccc_end;
struct arm_smccc_res res;
if (!entry->matches(entry, SCOPE_LOCAL_CPU))
return false;
if (psci_ops.smccc_version == SMCCC_VERSION_1_0)
return false;
switch (psci_ops.conduit) {
case PSCI_CONDUIT_HVC:
arm_smccc_1_1_hvc(ARM_SMCCC_ARCH_FEATURES_FUNC_ID,
ARM_SMCCC_ARCH_WORKAROUND_1, &res);
if (res.a0)
return false;
cb = call_hvc_arch_workaround_1;
smccc_start = __smccc_workaround_1_hvc_start;
smccc_end = __smccc_workaround_1_hvc_end;
break;
case PSCI_CONDUIT_SMC:
arm_smccc_1_1_smc(ARM_SMCCC_ARCH_FEATURES_FUNC_ID,
ARM_SMCCC_ARCH_WORKAROUND_1, &res);
if (res.a0)
return false;
cb = call_smc_arch_workaround_1;
smccc_start = __smccc_workaround_1_smc_start;
smccc_end = __smccc_workaround_1_smc_end;
break;
default:
return false;
}
install_bp_hardening_cb(entry, cb, smccc_start, smccc_end);
return true;
}
static int enable_psci_bp_hardening(void *data)
{
const struct arm64_cpu_capabilities *entry = data;
if (psci_ops.get_version)
if (psci_ops.get_version) {
if (check_smccc_arch_workaround_1(entry))
return 0;
install_bp_hardening_cb(entry,
(bp_hardening_cb_t)psci_ops.get_version,
__psci_hyp_bp_inval_start,
__psci_hyp_bp_inval_end);
}
return 0;
}