Merge tag 'kvmarm-fixes-6.18-2' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD

KVM/arm654 fixes for 6.18, take #2

* Core fixes

  - Fix trapping regression when no in-kernel irqchip is present
    ([email protected])

  - Check host-provided, untrusted ranges and offsets in pKVM
    ([email protected])
    ([email protected])

  - Fix regression restoring the ID_PFR1_EL1 register
    ([email protected]

  - Fix vgic ITS locking issues when LPIs are not directly injected
    ([email protected])

* Test fixes

  - Correct target CPU programming in vgic_lpi_stress selftest
    ([email protected])

  - Fix exposure of SCTLR2_EL2 and ZCR_EL2 in get-reg-list selftest
    (20251023-b4-kvm-arm64-get-reg-list-sctlr-el2-v1-1-088f88ff992a@kernel.org)
    (20251024-kvm-arm64-get-reg-list-zcr-el2-v1-1-0cd0ff75e22f@kernel.org)

* Misc

  - Update Oliver's email address
    ([email protected])

Author: bonzini

.mailmap

@@ -605,7 +605,8 @@ Oleksij Rempel <[email protected]>
 Oleksij Rempel <[email protected]> <[email protected]>
 Oliver Hartkopp <[email protected]> <[email protected]>
 Oliver Hartkopp <[email protected]> <[email protected]>
-Oliver Upton <[email protected]> <[email protected]>
+Oliver Upton <[email protected]> <[email protected]>
+Oliver Upton <[email protected]> <[email protected]>
 Ondřej Jirman <[email protected]> <[email protected]>
 Oza Pawandeep <[email protected]> <[email protected]>
 Pali Rohár <[email protected]> <[email protected]>

MAINTAINERS

@@ -13656,7 +13656,7 @@ F:	virt/kvm/*
 
 KERNEL VIRTUAL MACHINE FOR ARM64 (KVM/arm64)
 M:	Marc Zyngier <[email protected]>
-M:	Oliver Upton <[email protected]>
+M:	Oliver Upton <[email protected]>
 R:	Joey Gouly <[email protected]>
 R:	Suzuki K Poulose <[email protected]>
 R:	Zenghui Yu <[email protected]>

arch/arm64/kvm/hyp/nvhe/ffa.c

@@ -479,7 +479,7 @@ static void __do_ffa_mem_xfer(const u64 func_id,
 	struct ffa_mem_region_attributes *ep_mem_access;
 	struct ffa_composite_mem_region *reg;
 	struct ffa_mem_region *buf;
-	u32 offset, nr_ranges;
+	u32 offset, nr_ranges, checked_offset;
 	int ret = 0;
 
 	if (addr_mbz || npages_mbz || fraglen > len ||
@@ -516,7 +516,12 @@ static void __do_ffa_mem_xfer(const u64 func_id,
 		goto out_unlock;
 	}
 
-	if (fraglen < offset + sizeof(struct ffa_composite_mem_region)) {
+	if (check_add_overflow(offset, sizeof(struct ffa_composite_mem_region), &checked_offset)) {
+		ret = FFA_RET_INVALID_PARAMETERS;
+		goto out_unlock;
+	}
+
+	if (fraglen < checked_offset) {
 		ret = FFA_RET_INVALID_PARAMETERS;
 		goto out_unlock;
 	}

arch/arm64/kvm/hyp/nvhe/mem_protect.c

@@ -367,6 +367,19 @@ static int host_stage2_unmap_dev_all(void)
 	return kvm_pgtable_stage2_unmap(pgt, addr, BIT(pgt->ia_bits) - addr);
 }
 
+/*
+ * Ensure the PFN range is contained within PA-range.
+ *
+ * This check is also robust to overflows and is therefore a requirement before
+ * using a pfn/nr_pages pair from an untrusted source.
+ */
+static bool pfn_range_is_valid(u64 pfn, u64 nr_pages)
+{
+	u64 limit = BIT(kvm_phys_shift(&host_mmu.arch.mmu) - PAGE_SHIFT);
+
+	return pfn < limit && ((limit - pfn) >= nr_pages);
+}
+
 struct kvm_mem_range {
 	u64 start;
 	u64 end;
@@ -776,6 +789,9 @@ int __pkvm_host_donate_hyp(u64 pfn, u64 nr_pages)
 	void *virt = __hyp_va(phys);
 	int ret;
 
+	if (!pfn_range_is_valid(pfn, nr_pages))
+		return -EINVAL;
+
 	host_lock_component();
 	hyp_lock_component();
 
@@ -804,6 +820,9 @@ int __pkvm_hyp_donate_host(u64 pfn, u64 nr_pages)
 	u64 virt = (u64)__hyp_va(phys);
 	int ret;
 
+	if (!pfn_range_is_valid(pfn, nr_pages))
+		return -EINVAL;
+
 	host_lock_component();
 	hyp_lock_component();
 
@@ -887,6 +906,9 @@ int __pkvm_host_share_ffa(u64 pfn, u64 nr_pages)
 	u64 size = PAGE_SIZE * nr_pages;
 	int ret;
 
+	if (!pfn_range_is_valid(pfn, nr_pages))
+		return -EINVAL;
+
 	host_lock_component();
 	ret = __host_check_page_state_range(phys, size, PKVM_PAGE_OWNED);
 	if (!ret)
@@ -902,6 +924,9 @@ int __pkvm_host_unshare_ffa(u64 pfn, u64 nr_pages)
 	u64 size = PAGE_SIZE * nr_pages;
 	int ret;
 
+	if (!pfn_range_is_valid(pfn, nr_pages))
+		return -EINVAL;
+
 	host_lock_component();
 	ret = __host_check_page_state_range(phys, size, PKVM_PAGE_SHARED_OWNED);
 	if (!ret)
@@ -945,6 +970,9 @@ int __pkvm_host_share_guest(u64 pfn, u64 gfn, u64 nr_pages, struct pkvm_hyp_vcpu
 	if (prot & ~KVM_PGTABLE_PROT_RWX)
 		return -EINVAL;
 
+	if (!pfn_range_is_valid(pfn, nr_pages))
+		return -EINVAL;
+
 	ret = __guest_check_transition_size(phys, ipa, nr_pages, &size);
 	if (ret)
 		return ret;

arch/arm64/kvm/sys_regs.c

@@ -2595,19 +2595,23 @@ static bool bad_redir_trap(struct kvm_vcpu *vcpu,
 	.val = 0,				\
 }
 
-/* sys_reg_desc initialiser for known cpufeature ID registers */
-#define AA32_ID_SANITISED(name) {		\
-	ID_DESC(name),				\
-	.visibility = aa32_id_visibility,	\
-	.val = 0,				\
-}
-
 /* sys_reg_desc initialiser for writable ID registers */
 #define ID_WRITABLE(name, mask) {		\
 	ID_DESC(name),				\
 	.val = mask,				\
 }
 
+/*
+ * 32bit ID regs are fully writable when the guest is 32bit
+ * capable. Nothing in the KVM code should rely on 32bit features
+ * anyway, only 64bit, so let the VMM do its worse.
+ */
+#define AA32_ID_WRITABLE(name) {		\
+	ID_DESC(name),				\
+	.visibility = aa32_id_visibility,	\
+	.val = GENMASK(31, 0),			\
+}
+
 /* sys_reg_desc initialiser for cpufeature ID registers that need filtering */
 #define ID_FILTERED(sysreg, name, mask) {	\
 	ID_DESC(sysreg),				\
@@ -3128,40 +3132,39 @@ static const struct sys_reg_desc sys_reg_descs[] = {
 
 	/* AArch64 mappings of the AArch32 ID registers */
 	/* CRm=1 */
-	AA32_ID_SANITISED(ID_PFR0_EL1),
-	AA32_ID_SANITISED(ID_PFR1_EL1),
+	AA32_ID_WRITABLE(ID_PFR0_EL1),
+	AA32_ID_WRITABLE(ID_PFR1_EL1),
 	{ SYS_DESC(SYS_ID_DFR0_EL1),
 	  .access = access_id_reg,
 	  .get_user = get_id_reg,
 	  .set_user = set_id_dfr0_el1,
 	  .visibility = aa32_id_visibility,
 	  .reset = read_sanitised_id_dfr0_el1,
-	  .val = ID_DFR0_EL1_PerfMon_MASK |
-		 ID_DFR0_EL1_CopDbg_MASK, },
+	  .val = GENMASK(31, 0) },
 	ID_HIDDEN(ID_AFR0_EL1),
-	AA32_ID_SANITISED(ID_MMFR0_EL1),
-	AA32_ID_SANITISED(ID_MMFR1_EL1),
-	AA32_ID_SANITISED(ID_MMFR2_EL1),
-	AA32_ID_SANITISED(ID_MMFR3_EL1),
+	AA32_ID_WRITABLE(ID_MMFR0_EL1),
+	AA32_ID_WRITABLE(ID_MMFR1_EL1),
+	AA32_ID_WRITABLE(ID_MMFR2_EL1),
+	AA32_ID_WRITABLE(ID_MMFR3_EL1),
 
 	/* CRm=2 */
-	AA32_ID_SANITISED(ID_ISAR0_EL1),
-	AA32_ID_SANITISED(ID_ISAR1_EL1),
-	AA32_ID_SANITISED(ID_ISAR2_EL1),
-	AA32_ID_SANITISED(ID_ISAR3_EL1),
-	AA32_ID_SANITISED(ID_ISAR4_EL1),
-	AA32_ID_SANITISED(ID_ISAR5_EL1),
-	AA32_ID_SANITISED(ID_MMFR4_EL1),
-	AA32_ID_SANITISED(ID_ISAR6_EL1),
+	AA32_ID_WRITABLE(ID_ISAR0_EL1),
+	AA32_ID_WRITABLE(ID_ISAR1_EL1),
+	AA32_ID_WRITABLE(ID_ISAR2_EL1),
+	AA32_ID_WRITABLE(ID_ISAR3_EL1),
+	AA32_ID_WRITABLE(ID_ISAR4_EL1),
+	AA32_ID_WRITABLE(ID_ISAR5_EL1),
+	AA32_ID_WRITABLE(ID_MMFR4_EL1),
+	AA32_ID_WRITABLE(ID_ISAR6_EL1),
 
 	/* CRm=3 */
-	AA32_ID_SANITISED(MVFR0_EL1),
-	AA32_ID_SANITISED(MVFR1_EL1),
-	AA32_ID_SANITISED(MVFR2_EL1),
+	AA32_ID_WRITABLE(MVFR0_EL1),
+	AA32_ID_WRITABLE(MVFR1_EL1),
+	AA32_ID_WRITABLE(MVFR2_EL1),
 	ID_UNALLOCATED(3,3),
-	AA32_ID_SANITISED(ID_PFR2_EL1),
+	AA32_ID_WRITABLE(ID_PFR2_EL1),
 	ID_HIDDEN(ID_DFR1_EL1),
-	AA32_ID_SANITISED(ID_MMFR5_EL1),
+	AA32_ID_WRITABLE(ID_MMFR5_EL1),
 	ID_UNALLOCATED(3,7),
 
 	/* AArch64 ID registers */
@@ -5606,11 +5609,13 @@ int kvm_finalize_sys_regs(struct kvm_vcpu *vcpu)
 
 	guard(mutex)(&kvm->arch.config_lock);
 
-	if (!(static_branch_unlikely(&kvm_vgic_global_state.gicv3_cpuif) &&
-	      irqchip_in_kernel(kvm) &&
-	      kvm->arch.vgic.vgic_model == KVM_DEV_TYPE_ARM_VGIC_V3)) {
-		kvm->arch.id_regs[IDREG_IDX(SYS_ID_AA64PFR0_EL1)] &= ~ID_AA64PFR0_EL1_GIC_MASK;
-		kvm->arch.id_regs[IDREG_IDX(SYS_ID_PFR1_EL1)] &= ~ID_PFR1_EL1_GIC_MASK;
+	if (!irqchip_in_kernel(kvm)) {
+		u64 val;
+
+		val = kvm_read_vm_id_reg(kvm, SYS_ID_AA64PFR0_EL1) & ~ID_AA64PFR0_EL1_GIC;
+		kvm_set_vm_id_reg(kvm, SYS_ID_AA64PFR0_EL1, val);
+		val = kvm_read_vm_id_reg(kvm, SYS_ID_PFR1_EL1) & ~ID_PFR1_EL1_GIC;
+		kvm_set_vm_id_reg(kvm, SYS_ID_PFR1_EL1, val);
 	}
 
 	if (vcpu_has_nv(vcpu)) {

arch/arm64/kvm/vgic/vgic-debug.c

@@ -64,29 +64,37 @@ static void iter_next(struct kvm *kvm, struct vgic_state_iter *iter)
 static int iter_mark_lpis(struct kvm *kvm)
 {
 	struct vgic_dist *dist = &kvm->arch.vgic;
+	unsigned long intid, flags;
 	struct vgic_irq *irq;
-	unsigned long intid;
 	int nr_lpis = 0;
 
+	xa_lock_irqsave(&dist->lpi_xa, flags);
+
 	xa_for_each(&dist->lpi_xa, intid, irq) {
 		if (!vgic_try_get_irq_ref(irq))
 			continue;
 
-		xa_set_mark(&dist->lpi_xa, intid, LPI_XA_MARK_DEBUG_ITER);
+		__xa_set_mark(&dist->lpi_xa, intid, LPI_XA_MARK_DEBUG_ITER);
 		nr_lpis++;
 	}
 
+	xa_unlock_irqrestore(&dist->lpi_xa, flags);
+
 	return nr_lpis;
 }
 
 static void iter_unmark_lpis(struct kvm *kvm)
 {
 	struct vgic_dist *dist = &kvm->arch.vgic;
+	unsigned long intid, flags;
 	struct vgic_irq *irq;
-	unsigned long intid;
 
 	xa_for_each_marked(&dist->lpi_xa, intid, irq, LPI_XA_MARK_DEBUG_ITER) {
-		xa_clear_mark(&dist->lpi_xa, intid, LPI_XA_MARK_DEBUG_ITER);
+		xa_lock_irqsave(&dist->lpi_xa, flags);
+		__xa_clear_mark(&dist->lpi_xa, intid, LPI_XA_MARK_DEBUG_ITER);
+		xa_unlock_irqrestore(&dist->lpi_xa, flags);
+
+		/* vgic_put_irq() expects to be called outside of the xa_lock */
 		vgic_put_irq(kvm, irq);
 	}
 }

arch/arm64/kvm/vgic/vgic-init.c

@@ -53,7 +53,7 @@ void kvm_vgic_early_init(struct kvm *kvm)
 {
 	struct vgic_dist *dist = &kvm->arch.vgic;
 
-	xa_init(&dist->lpi_xa);
+	xa_init_flags(&dist->lpi_xa, XA_FLAGS_LOCK_IRQ);
 }
 
 /* CREATION */
@@ -71,6 +71,7 @@ static int vgic_allocate_private_irqs_locked(struct kvm_vcpu *vcpu, u32 type);
 int kvm_vgic_create(struct kvm *kvm, u32 type)
 {
 	struct kvm_vcpu *vcpu;
+	u64 aa64pfr0, pfr1;
 	unsigned long i;
 	int ret;
 
@@ -161,10 +162,19 @@ int kvm_vgic_create(struct kvm *kvm, u32 type)
 
 	kvm->arch.vgic.vgic_dist_base = VGIC_ADDR_UNDEF;
 
-	if (type == KVM_DEV_TYPE_ARM_VGIC_V2)
+	aa64pfr0 = kvm_read_vm_id_reg(kvm, SYS_ID_AA64PFR0_EL1) & ~ID_AA64PFR0_EL1_GIC;
+	pfr1 = kvm_read_vm_id_reg(kvm, SYS_ID_PFR1_EL1) & ~ID_PFR1_EL1_GIC;
+
+	if (type == KVM_DEV_TYPE_ARM_VGIC_V2) {
 		kvm->arch.vgic.vgic_cpu_base = VGIC_ADDR_UNDEF;
-	else
+	} else {
 		INIT_LIST_HEAD(&kvm->arch.vgic.rd_regions);
+		aa64pfr0 |= SYS_FIELD_PREP_ENUM(ID_AA64PFR0_EL1, GIC, IMP);
+		pfr1 |= SYS_FIELD_PREP_ENUM(ID_PFR1_EL1, GIC, GICv3);
+	}
+
+	kvm_set_vm_id_reg(kvm, SYS_ID_AA64PFR0_EL1, aa64pfr0);
+	kvm_set_vm_id_reg(kvm, SYS_ID_PFR1_EL1, pfr1);
 
 	if (type == KVM_DEV_TYPE_ARM_VGIC_V3)
 		kvm->arch.vgic.nassgicap = system_supports_direct_sgis();

arch/arm64/kvm/vgic/vgic-its.c

@@ -78,6 +78,7 @@ static struct vgic_irq *vgic_add_lpi(struct kvm *kvm, u32 intid,
 {
 	struct vgic_dist *dist = &kvm->arch.vgic;
 	struct vgic_irq *irq = vgic_get_irq(kvm, intid), *oldirq;
+	unsigned long flags;
 	int ret;
 
 	/* In this case there is no put, since we keep the reference. */
@@ -88,7 +89,7 @@ static struct vgic_irq *vgic_add_lpi(struct kvm *kvm, u32 intid,
 	if (!irq)
 		return ERR_PTR(-ENOMEM);
 
-	ret = xa_reserve(&dist->lpi_xa, intid, GFP_KERNEL_ACCOUNT);
+	ret = xa_reserve_irq(&dist->lpi_xa, intid, GFP_KERNEL_ACCOUNT);
 	if (ret) {
 		kfree(irq);
 		return ERR_PTR(ret);
@@ -103,7 +104,7 @@ static struct vgic_irq *vgic_add_lpi(struct kvm *kvm, u32 intid,
 	irq->target_vcpu = vcpu;
 	irq->group = 1;
 
-	xa_lock(&dist->lpi_xa);
+	xa_lock_irqsave(&dist->lpi_xa, flags);
 
 	/*
 	 * There could be a race with another vgic_add_lpi(), so we need to
@@ -114,21 +115,18 @@ static struct vgic_irq *vgic_add_lpi(struct kvm *kvm, u32 intid,
 		/* Someone was faster with adding this LPI, lets use that. */
 		kfree(irq);
 		irq = oldirq;
-
-		goto out_unlock;
+	} else {
+		ret = xa_err(__xa_store(&dist->lpi_xa, intid, irq, 0));
 	}
 
-	ret = xa_err(__xa_store(&dist->lpi_xa, intid, irq, 0));
+	xa_unlock_irqrestore(&dist->lpi_xa, flags);
+
 	if (ret) {
 		xa_release(&dist->lpi_xa, intid);
 		kfree(irq);
-	}
-
-out_unlock:
-	xa_unlock(&dist->lpi_xa);
 
-	if (ret)
 		return ERR_PTR(ret);
+	}
 
 	/*
 	 * We "cache" the configuration table entries in our struct vgic_irq's.

arch/arm64/kvm/vgic/vgic-v3.c

@@ -301,7 +301,8 @@ void vcpu_set_ich_hcr(struct kvm_vcpu *vcpu)
 		return;
 
 	/* Hide GICv3 sysreg if necessary */
-	if (vcpu->kvm->arch.vgic.vgic_model == KVM_DEV_TYPE_ARM_VGIC_V2) {
+	if (vcpu->kvm->arch.vgic.vgic_model == KVM_DEV_TYPE_ARM_VGIC_V2 ||
+	    !irqchip_in_kernel(vcpu->kvm)) {
 		vgic_v3->vgic_hcr |= (ICH_HCR_EL2_TALL0 | ICH_HCR_EL2_TALL1 |
 				      ICH_HCR_EL2_TC);
 		return;