The patch below does not apply to the 4.16-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From f9f5dc19509bbef6f5e675346f1a7d7b846bdb12 Mon Sep 17 00:00:00 2001
From: Shanker Donthineni shankerd@codeaurora.org Date: Mon, 5 Mar 2018 11:06:43 -0600 Subject: [PATCH] arm64: KVM: Use SMCCC_ARCH_WORKAROUND_1 for Falkor BP hardening
The function SMCCC_ARCH_WORKAROUND_1 was introduced as part of SMC V1.1 Calling Convention to mitigate CVE-2017-5715. This patch uses the standard call SMCCC_ARCH_WORKAROUND_1 for Falkor chips instead of Silicon provider service ID 0xC2001700.
Cc: stable@vger.kernel.org # 4.14+ Signed-off-by: Shanker Donthineni shankerd@codeaurora.org Signed-off-by: Marc Zyngier marc.zyngier@arm.com
diff --git a/arch/arm64/include/asm/cpucaps.h b/arch/arm64/include/asm/cpucaps.h index d4cc54ed0656..c7dfe68fbcc7 100644 --- a/arch/arm64/include/asm/cpucaps.h +++ b/arch/arm64/include/asm/cpucaps.h @@ -43,7 +43,7 @@ #define ARM64_SVE 22 #define ARM64_UNMAP_KERNEL_AT_EL0 23 #define ARM64_HARDEN_BRANCH_PREDICTOR 24 -#define ARM64_HARDEN_BP_POST_GUEST_EXIT 25 +/* #define ARM64_UNUSED_CAP_TO_BE_REMOVED 25 */ #define ARM64_HAS_RAS_EXTN 26
#define ARM64_NCAPS 27 diff --git a/arch/arm64/include/asm/kvm_asm.h b/arch/arm64/include/asm/kvm_asm.h index d53d40704416..f6648a3e4152 100644 --- a/arch/arm64/include/asm/kvm_asm.h +++ b/arch/arm64/include/asm/kvm_asm.h @@ -71,8 +71,6 @@ extern u32 __kvm_get_mdcr_el2(void);
extern u32 __init_stage2_translation(void);
-extern void __qcom_hyp_sanitize_btac_predictors(void); - #else /* __ASSEMBLY__ */
.macro get_host_ctxt reg, tmp diff --git a/arch/arm64/kernel/bpi.S b/arch/arm64/kernel/bpi.S index bb0b67722e86..9404f6aecda7 100644 --- a/arch/arm64/kernel/bpi.S +++ b/arch/arm64/kernel/bpi.S @@ -74,14 +74,6 @@ ENTRY(__bp_harden_hyp_vecs_end)
.popsection
-ENTRY(__qcom_hyp_sanitize_link_stack_start) - stp x29, x30, [sp, #-16]! - .rept 16 - bl . + 4 - .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)] diff --git a/arch/arm64/kernel/cpu_errata.c b/arch/arm64/kernel/cpu_errata.c index aacdc118c4c9..caa73af7d26e 100644 --- a/arch/arm64/kernel/cpu_errata.c +++ b/arch/arm64/kernel/cpu_errata.c @@ -69,8 +69,6 @@ atomic_t arm64_el2_vector_last_slot = ATOMIC_INIT(-1); DEFINE_PER_CPU_READ_MOSTLY(struct bp_hardening_data, bp_hardening_data);
#ifdef CONFIG_KVM -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[]; @@ -114,8 +112,6 @@ static void __install_bp_hardening_cb(bp_hardening_cb_t fn, spin_unlock(&bp_lock); } #else -#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 @@ -160,12 +156,25 @@ static void call_hvc_arch_workaround_1(void) arm_smccc_1_1_hvc(ARM_SMCCC_ARCH_WORKAROUND_1, NULL); }
+static void qcom_link_stack_sanitization(void) +{ + u64 tmp; + + asm volatile("mov %0, x30 \n" + ".rept 16 \n" + "bl . + 4 \n" + ".endr \n" + "mov x30, %0 \n" + : "=&r" (tmp)); +} + static int enable_smccc_arch_workaround_1(void *data) { const struct arm64_cpu_capabilities *entry = data; bp_hardening_cb_t cb; void *smccc_start, *smccc_end; struct arm_smccc_res res; + u32 midr = read_cpuid_id();
if (!entry->matches(entry, SCOPE_LOCAL_CPU)) return 0; @@ -198,33 +207,15 @@ static int enable_smccc_arch_workaround_1(void *data) return 0; }
+ if (((midr & MIDR_CPU_MODEL_MASK) == MIDR_QCOM_FALKOR) || + ((midr & MIDR_CPU_MODEL_MASK) == MIDR_QCOM_FALKOR_V1)) + cb = qcom_link_stack_sanitization; + install_bp_hardening_cb(entry, cb, smccc_start, smccc_end);
return 0; }
-static void qcom_link_stack_sanitization(void) -{ - u64 tmp; - - asm volatile("mov %0, x30 \n" - ".rept 16 \n" - "bl . + 4 \n" - ".endr \n" - "mov x30, %0 \n" - : "=&r" (tmp)); -} - -static int qcom_enable_link_stack_sanitization(void *data) -{ - const struct arm64_cpu_capabilities *entry = data; - - install_bp_hardening_cb(entry, qcom_link_stack_sanitization, - __qcom_hyp_sanitize_link_stack_start, - __qcom_hyp_sanitize_link_stack_end); - - return 0; -} #endif /* CONFIG_HARDEN_BRANCH_PREDICTOR */
#define MIDR_RANGE(model, min, max) \ @@ -399,20 +390,12 @@ const struct arm64_cpu_capabilities arm64_errata[] = { { .capability = ARM64_HARDEN_BRANCH_PREDICTOR, MIDR_ALL_VERSIONS(MIDR_QCOM_FALKOR_V1), - .enable = qcom_enable_link_stack_sanitization, - }, - { - .capability = ARM64_HARDEN_BP_POST_GUEST_EXIT, - MIDR_ALL_VERSIONS(MIDR_QCOM_FALKOR_V1), + .enable = enable_smccc_arch_workaround_1, }, { .capability = ARM64_HARDEN_BRANCH_PREDICTOR, MIDR_ALL_VERSIONS(MIDR_QCOM_FALKOR), - .enable = qcom_enable_link_stack_sanitization, - }, - { - .capability = ARM64_HARDEN_BP_POST_GUEST_EXIT, - MIDR_ALL_VERSIONS(MIDR_QCOM_FALKOR), + .enable = enable_smccc_arch_workaround_1, }, { .capability = ARM64_HARDEN_BRANCH_PREDICTOR, diff --git a/arch/arm64/kvm/hyp/entry.S b/arch/arm64/kvm/hyp/entry.S index 1f458f7c3b44..e41a161d313a 100644 --- a/arch/arm64/kvm/hyp/entry.S +++ b/arch/arm64/kvm/hyp/entry.S @@ -209,15 +209,3 @@ alternative_endif
eret ENDPROC(__fpsimd_guest_restore) - -ENTRY(__qcom_hyp_sanitize_btac_predictors) - /** - * Call SMC64 with Silicon provider serviceID 23<<8 (0xc2001700) - * 0xC2000000-0xC200FFFF: assigned to SiP Service Calls - * b15-b0: contains SiP functionID - */ - movz x0, #0x1700 - movk x0, #0xc200, lsl #16 - smc #0 - ret -ENDPROC(__qcom_hyp_sanitize_btac_predictors) diff --git a/arch/arm64/kvm/hyp/switch.c b/arch/arm64/kvm/hyp/switch.c index 07b572173265..d9645236e474 100644 --- a/arch/arm64/kvm/hyp/switch.c +++ b/arch/arm64/kvm/hyp/switch.c @@ -472,16 +472,6 @@ int __hyp_text __kvm_vcpu_run_nvhe(struct kvm_vcpu *vcpu) /* And we're baaack! */ } while (fixup_guest_exit(vcpu, &exit_code));
- if (cpus_have_const_cap(ARM64_HARDEN_BP_POST_GUEST_EXIT)) { - u32 midr = read_cpuid_id(); - - /* Apply BTAC predictors mitigation to all Falkor chips */ - if (((midr & MIDR_CPU_MODEL_MASK) == MIDR_QCOM_FALKOR) || - ((midr & MIDR_CPU_MODEL_MASK) == MIDR_QCOM_FALKOR_V1)) { - __qcom_hyp_sanitize_btac_predictors(); - } - } - fp_enabled = __fpsimd_enabled_nvhe();
__sysreg_save_state_nvhe(guest_ctxt);