From 404f6aac9b3ef595735feca99979db084ea48315 Mon Sep 17 00:00:00 2001 From: Kees Cook Date: Mon, 8 Aug 2016 16:29:06 -0700 Subject: [PATCH] x86: Apply more __ro_after_init and const Guided by grsecurity's analogous __read_only markings in arch/x86, this applies several uses of __ro_after_init to structures that are only updated during __init, and const for some structures that are never updated. Additionally extends __init markings to some functions that are only used during __init, and cleans up some missing C99 style static initializers. Signed-off-by: Kees Cook Cc: Andy Lutomirski Cc: Andy Lutomirski Cc: Arnd Bergmann Cc: Borislav Petkov Cc: Brad Spengler Cc: Brian Gerst Cc: David Brown Cc: Denys Vlasenko Cc: Emese Revfy Cc: H. Peter Anvin Cc: Josh Poimboeuf Cc: Linus Torvalds Cc: Mathias Krause Cc: Michael Ellerman Cc: PaX Team Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: kernel-hardening@lists.openwall.com Link: http://lkml.kernel.org/r/20160808232906.GA29731@www.outflux.net Signed-off-by: Ingo Molnar --- arch/x86/include/asm/desc.h | 2 +- arch/x86/include/asm/fpu/xstate.h | 3 ++- arch/x86/kernel/apic/apic_flat_64.c | 6 +++--- arch/x86/kernel/apic/apic_noop.c | 2 +- arch/x86/kernel/apic/bigsmp_32.c | 2 +- arch/x86/kernel/apic/msi.c | 2 +- arch/x86/kernel/apic/probe_32.c | 4 ++-- arch/x86/kernel/apic/x2apic_cluster.c | 2 +- arch/x86/kernel/apic/x2apic_phys.c | 2 +- arch/x86/kernel/apic/x2apic_uv_x.c | 2 +- arch/x86/kernel/cpu/common.c | 11 ++++++++--- arch/x86/kernel/cpu/mtrr/main.c | 4 ++-- arch/x86/kernel/cpu/mtrr/mtrr.h | 2 +- arch/x86/kernel/ksysfs.c | 2 +- arch/x86/kernel/kvmclock.c | 2 +- arch/x86/kernel/paravirt.c | 2 +- arch/x86/kernel/ptrace.c | 6 +++--- arch/x86/kernel/reboot.c | 2 +- arch/x86/kernel/setup.c | 4 ++-- arch/x86/kernel/setup_percpu.c | 2 +- arch/x86/kernel/x86_init.c | 6 +++--- arch/x86/kvm/svm.c | 2 +- arch/x86/kvm/vmx.c | 2 +- arch/x86/pci/pcbios.c | 7 +++++-- 24 files changed, 45 insertions(+), 36 deletions(-) diff --git a/arch/x86/include/asm/desc.h b/arch/x86/include/asm/desc.h index 4e10d73cf018..12080d87da3b 100644 --- a/arch/x86/include/asm/desc.h +++ b/arch/x86/include/asm/desc.h @@ -36,7 +36,7 @@ static inline void fill_ldt(struct desc_struct *desc, const struct user_desc *in extern struct desc_ptr idt_descr; extern gate_desc idt_table[]; -extern struct desc_ptr debug_idt_descr; +extern const struct desc_ptr debug_idt_descr; extern gate_desc debug_idt_table[]; struct gdt_page { diff --git a/arch/x86/include/asm/fpu/xstate.h b/arch/x86/include/asm/fpu/xstate.h index ae55a43e09c0..d4957ac72b48 100644 --- a/arch/x86/include/asm/fpu/xstate.h +++ b/arch/x86/include/asm/fpu/xstate.h @@ -45,7 +45,8 @@ extern u64 xfeatures_mask; extern u64 xstate_fx_sw_bytes[USER_XSTATE_FX_SW_WORDS]; -extern void update_regset_xstate_info(unsigned int size, u64 xstate_mask); +extern void __init update_regset_xstate_info(unsigned int size, + u64 xstate_mask); void fpu__xstate_clear_all_cpu_caps(void); void *get_xsave_addr(struct xregs_state *xsave, int xstate); diff --git a/arch/x86/kernel/apic/apic_flat_64.c b/arch/x86/kernel/apic/apic_flat_64.c index 5b2ae106bd4a..8862da76ef6f 100644 --- a/arch/x86/kernel/apic/apic_flat_64.c +++ b/arch/x86/kernel/apic/apic_flat_64.c @@ -25,7 +25,7 @@ static struct apic apic_physflat; static struct apic apic_flat; -struct apic __read_mostly *apic = &apic_flat; +struct apic *apic __ro_after_init = &apic_flat; EXPORT_SYMBOL_GPL(apic); static int flat_acpi_madt_oem_check(char *oem_id, char *oem_table_id) @@ -154,7 +154,7 @@ static int flat_probe(void) return 1; } -static struct apic apic_flat = { +static struct apic apic_flat __ro_after_init = { .name = "flat", .probe = flat_probe, .acpi_madt_oem_check = flat_acpi_madt_oem_check, @@ -248,7 +248,7 @@ static int physflat_probe(void) return 0; } -static struct apic apic_physflat = { +static struct apic apic_physflat __ro_after_init = { .name = "physical flat", .probe = physflat_probe, diff --git a/arch/x86/kernel/apic/apic_noop.c b/arch/x86/kernel/apic/apic_noop.c index c05688b2deff..b109e4389c92 100644 --- a/arch/x86/kernel/apic/apic_noop.c +++ b/arch/x86/kernel/apic/apic_noop.c @@ -108,7 +108,7 @@ static void noop_apic_write(u32 reg, u32 v) WARN_ON_ONCE(boot_cpu_has(X86_FEATURE_APIC) && !disable_apic); } -struct apic apic_noop = { +struct apic apic_noop __ro_after_init = { .name = "noop", .probe = noop_probe, .acpi_madt_oem_check = NULL, diff --git a/arch/x86/kernel/apic/bigsmp_32.c b/arch/x86/kernel/apic/bigsmp_32.c index 06dbaa458bfe..56012010332c 100644 --- a/arch/x86/kernel/apic/bigsmp_32.c +++ b/arch/x86/kernel/apic/bigsmp_32.c @@ -142,7 +142,7 @@ static int probe_bigsmp(void) return dmi_bigsmp; } -static struct apic apic_bigsmp = { +static struct apic apic_bigsmp __ro_after_init = { .name = "bigsmp", .probe = probe_bigsmp, diff --git a/arch/x86/kernel/apic/msi.c b/arch/x86/kernel/apic/msi.c index ade25320df96..015bbf30e3e3 100644 --- a/arch/x86/kernel/apic/msi.c +++ b/arch/x86/kernel/apic/msi.c @@ -269,7 +269,7 @@ static void hpet_msi_write_msg(struct irq_data *data, struct msi_msg *msg) hpet_msi_write(irq_data_get_irq_handler_data(data), msg); } -static struct irq_chip hpet_msi_controller = { +static struct irq_chip hpet_msi_controller __ro_after_init = { .name = "HPET-MSI", .irq_unmask = hpet_msi_unmask, .irq_mask = hpet_msi_mask, diff --git a/arch/x86/kernel/apic/probe_32.c b/arch/x86/kernel/apic/probe_32.c index 7c43e716c158..e5fb2f086460 100644 --- a/arch/x86/kernel/apic/probe_32.c +++ b/arch/x86/kernel/apic/probe_32.c @@ -72,7 +72,7 @@ static int probe_default(void) return 1; } -static struct apic apic_default = { +static struct apic apic_default __ro_after_init = { .name = "default", .probe = probe_default, @@ -126,7 +126,7 @@ static struct apic apic_default = { apic_driver(apic_default); -struct apic *apic = &apic_default; +struct apic *apic __ro_after_init = &apic_default; EXPORT_SYMBOL_GPL(apic); static int cmdline_apic __initdata; diff --git a/arch/x86/kernel/apic/x2apic_cluster.c b/arch/x86/kernel/apic/x2apic_cluster.c index 6368fa69d2af..766bdef1e1d7 100644 --- a/arch/x86/kernel/apic/x2apic_cluster.c +++ b/arch/x86/kernel/apic/x2apic_cluster.c @@ -222,7 +222,7 @@ static void cluster_vector_allocation_domain(int cpu, struct cpumask *retmask, cpumask_and(retmask, mask, per_cpu(cpus_in_cluster, cpu)); } -static struct apic apic_x2apic_cluster = { +static struct apic apic_x2apic_cluster __ro_after_init = { .name = "cluster x2apic", .probe = x2apic_cluster_probe, diff --git a/arch/x86/kernel/apic/x2apic_phys.c b/arch/x86/kernel/apic/x2apic_phys.c index 4f13f54f1b1f..ff111f05a314 100644 --- a/arch/x86/kernel/apic/x2apic_phys.c +++ b/arch/x86/kernel/apic/x2apic_phys.c @@ -98,7 +98,7 @@ static int x2apic_phys_probe(void) return apic == &apic_x2apic_phys; } -static struct apic apic_x2apic_phys = { +static struct apic apic_x2apic_phys __ro_after_init = { .name = "physical x2apic", .probe = x2apic_phys_probe, diff --git a/arch/x86/kernel/apic/x2apic_uv_x.c b/arch/x86/kernel/apic/x2apic_uv_x.c index 09b59adaea3f..ed887dedd35e 100644 --- a/arch/x86/kernel/apic/x2apic_uv_x.c +++ b/arch/x86/kernel/apic/x2apic_uv_x.c @@ -554,7 +554,7 @@ static int uv_probe(void) return apic == &apic_x2apic_uv_x; } -static struct apic __refdata apic_x2apic_uv_x = { +static struct apic apic_x2apic_uv_x __ro_after_init = { .name = "UV large system", .probe = uv_probe, diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c index 809eda03c527..d3b91be4873b 100644 --- a/arch/x86/kernel/cpu/common.c +++ b/arch/x86/kernel/cpu/common.c @@ -1265,9 +1265,14 @@ static __init int setup_disablecpuid(char *arg) __setup("clearcpuid=", setup_disablecpuid); #ifdef CONFIG_X86_64 -struct desc_ptr idt_descr = { NR_VECTORS * 16 - 1, (unsigned long) idt_table }; -struct desc_ptr debug_idt_descr = { NR_VECTORS * 16 - 1, - (unsigned long) debug_idt_table }; +struct desc_ptr idt_descr __ro_after_init = { + .size = NR_VECTORS * 16 - 1, + .address = (unsigned long) idt_table, +}; +const struct desc_ptr debug_idt_descr = { + .size = NR_VECTORS * 16 - 1, + .address = (unsigned long) debug_idt_table, +}; DEFINE_PER_CPU_FIRST(union irq_stack_union, irq_stack_union) __aligned(PAGE_SIZE) __visible; diff --git a/arch/x86/kernel/cpu/mtrr/main.c b/arch/x86/kernel/cpu/mtrr/main.c index 28f1b54b7fad..24e87e74990d 100644 --- a/arch/x86/kernel/cpu/mtrr/main.c +++ b/arch/x86/kernel/cpu/mtrr/main.c @@ -72,14 +72,14 @@ static DEFINE_MUTEX(mtrr_mutex); u64 size_or_mask, size_and_mask; static bool mtrr_aps_delayed_init; -static const struct mtrr_ops *mtrr_ops[X86_VENDOR_NUM]; +static const struct mtrr_ops *mtrr_ops[X86_VENDOR_NUM] __ro_after_init; const struct mtrr_ops *mtrr_if; static void set_mtrr(unsigned int reg, unsigned long base, unsigned long size, mtrr_type type); -void set_mtrr_ops(const struct mtrr_ops *ops) +void __init set_mtrr_ops(const struct mtrr_ops *ops) { if (ops->vendor && ops->vendor < X86_VENDOR_NUM) mtrr_ops[ops->vendor] = ops; diff --git a/arch/x86/kernel/cpu/mtrr/mtrr.h b/arch/x86/kernel/cpu/mtrr/mtrr.h index 6c7ced07d16d..ad8bd763efa5 100644 --- a/arch/x86/kernel/cpu/mtrr/mtrr.h +++ b/arch/x86/kernel/cpu/mtrr/mtrr.h @@ -54,7 +54,7 @@ void fill_mtrr_var_range(unsigned int index, bool get_mtrr_state(void); void mtrr_bp_pat_init(void); -extern void set_mtrr_ops(const struct mtrr_ops *ops); +extern void __init set_mtrr_ops(const struct mtrr_ops *ops); extern u64 size_or_mask, size_and_mask; extern const struct mtrr_ops *mtrr_if; diff --git a/arch/x86/kernel/ksysfs.c b/arch/x86/kernel/ksysfs.c index c2bedaea11f7..4afc67f5facc 100644 --- a/arch/x86/kernel/ksysfs.c +++ b/arch/x86/kernel/ksysfs.c @@ -184,7 +184,7 @@ static ssize_t setup_data_data_read(struct file *fp, static struct kobj_attribute type_attr = __ATTR_RO(type); -static struct bin_attribute data_attr = { +static struct bin_attribute data_attr __ro_after_init = { .attr = { .name = "data", .mode = S_IRUGO, diff --git a/arch/x86/kernel/kvmclock.c b/arch/x86/kernel/kvmclock.c index 1d39bfbd26bb..0964399ef942 100644 --- a/arch/x86/kernel/kvmclock.c +++ b/arch/x86/kernel/kvmclock.c @@ -29,7 +29,7 @@ #include #include -static int kvmclock = 1; +static int kvmclock __ro_after_init = 1; static int msr_kvm_system_time = MSR_KVM_SYSTEM_TIME; static int msr_kvm_wall_clock = MSR_KVM_WALL_CLOCK; static cycle_t kvm_sched_clock_offset; diff --git a/arch/x86/kernel/paravirt.c b/arch/x86/kernel/paravirt.c index ad5bc9578a73..b8e4680a2e0b 100644 --- a/arch/x86/kernel/paravirt.c +++ b/arch/x86/kernel/paravirt.c @@ -389,7 +389,7 @@ NOKPROBE_SYMBOL(native_load_idt); #define PTE_IDENT __PV_IS_CALLEE_SAVE(_paravirt_ident_64) #endif -struct pv_mmu_ops pv_mmu_ops = { +struct pv_mmu_ops pv_mmu_ops __ro_after_init = { .read_cr2 = native_read_cr2, .write_cr2 = native_write_cr2, diff --git a/arch/x86/kernel/ptrace.c b/arch/x86/kernel/ptrace.c index f79576a541ff..2537cfba4d89 100644 --- a/arch/x86/kernel/ptrace.c +++ b/arch/x86/kernel/ptrace.c @@ -1250,7 +1250,7 @@ long compat_arch_ptrace(struct task_struct *child, compat_long_t request, #ifdef CONFIG_X86_64 -static struct user_regset x86_64_regsets[] __read_mostly = { +static struct user_regset x86_64_regsets[] __ro_after_init = { [REGSET_GENERAL] = { .core_note_type = NT_PRSTATUS, .n = sizeof(struct user_regs_struct) / sizeof(long), @@ -1291,7 +1291,7 @@ static const struct user_regset_view user_x86_64_view = { #endif /* CONFIG_X86_64 */ #if defined CONFIG_X86_32 || defined CONFIG_IA32_EMULATION -static struct user_regset x86_32_regsets[] __read_mostly = { +static struct user_regset x86_32_regsets[] __ro_after_init = { [REGSET_GENERAL] = { .core_note_type = NT_PRSTATUS, .n = sizeof(struct user_regs_struct32) / sizeof(u32), @@ -1344,7 +1344,7 @@ static const struct user_regset_view user_x86_32_view = { */ u64 xstate_fx_sw_bytes[USER_XSTATE_FX_SW_WORDS]; -void update_regset_xstate_info(unsigned int size, u64 xstate_mask) +void __init update_regset_xstate_info(unsigned int size, u64 xstate_mask) { #ifdef CONFIG_X86_64 x86_64_regsets[REGSET_XSTATE].n = size / sizeof(u64); diff --git a/arch/x86/kernel/reboot.c b/arch/x86/kernel/reboot.c index 63bf27d972b7..e244c19a2451 100644 --- a/arch/x86/kernel/reboot.c +++ b/arch/x86/kernel/reboot.c @@ -705,7 +705,7 @@ static void native_machine_power_off(void) tboot_shutdown(TB_SHUTDOWN_HALT); } -struct machine_ops machine_ops = { +struct machine_ops machine_ops __ro_after_init = { .power_off = native_machine_power_off, .shutdown = native_machine_shutdown, .emergency_restart = native_machine_emergency_restart, diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c index 95cf31c9f4ec..2d98798d395e 100644 --- a/arch/x86/kernel/setup.c +++ b/arch/x86/kernel/setup.c @@ -210,9 +210,9 @@ EXPORT_SYMBOL(boot_cpu_data); #if !defined(CONFIG_X86_PAE) || defined(CONFIG_X86_64) -__visible unsigned long mmu_cr4_features; +__visible unsigned long mmu_cr4_features __ro_after_init; #else -__visible unsigned long mmu_cr4_features = X86_CR4_PAE; +__visible unsigned long mmu_cr4_features __ro_after_init = X86_CR4_PAE; #endif /* Boot loader ID and version as integers, for the benefit of proc_dointvec */ diff --git a/arch/x86/kernel/setup_percpu.c b/arch/x86/kernel/setup_percpu.c index 7a40e068302d..1d5c79473639 100644 --- a/arch/x86/kernel/setup_percpu.c +++ b/arch/x86/kernel/setup_percpu.c @@ -33,7 +33,7 @@ EXPORT_PER_CPU_SYMBOL(cpu_number); DEFINE_PER_CPU_READ_MOSTLY(unsigned long, this_cpu_off) = BOOT_PERCPU_OFFSET; EXPORT_PER_CPU_SYMBOL(this_cpu_off); -unsigned long __per_cpu_offset[NR_CPUS] __read_mostly = { +unsigned long __per_cpu_offset[NR_CPUS] __ro_after_init = { [0 ... NR_CPUS-1] = BOOT_PERCPU_OFFSET, }; EXPORT_SYMBOL(__per_cpu_offset); diff --git a/arch/x86/kernel/x86_init.c b/arch/x86/kernel/x86_init.c index 76c5e52436c4..0bd9f1287f39 100644 --- a/arch/x86/kernel/x86_init.c +++ b/arch/x86/kernel/x86_init.c @@ -91,7 +91,7 @@ struct x86_cpuinit_ops x86_cpuinit = { static void default_nmi_init(void) { }; static int default_i8042_detect(void) { return 1; }; -struct x86_platform_ops x86_platform = { +struct x86_platform_ops x86_platform __ro_after_init = { .calibrate_cpu = native_calibrate_cpu, .calibrate_tsc = native_calibrate_tsc, .get_wallclock = mach_get_cmos_time, @@ -108,7 +108,7 @@ struct x86_platform_ops x86_platform = { EXPORT_SYMBOL_GPL(x86_platform); #if defined(CONFIG_PCI_MSI) -struct x86_msi_ops x86_msi = { +struct x86_msi_ops x86_msi __ro_after_init = { .setup_msi_irqs = native_setup_msi_irqs, .teardown_msi_irq = native_teardown_msi_irq, .teardown_msi_irqs = default_teardown_msi_irqs, @@ -137,7 +137,7 @@ void arch_restore_msi_irqs(struct pci_dev *dev) } #endif -struct x86_io_apic_ops x86_io_apic_ops = { +struct x86_io_apic_ops x86_io_apic_ops __ro_after_init = { .read = native_io_apic_read, .disable = native_disable_io_apic, }; diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c index af523d84d102..1e6b84b96ea6 100644 --- a/arch/x86/kvm/svm.c +++ b/arch/x86/kvm/svm.c @@ -4961,7 +4961,7 @@ static inline void avic_post_state_restore(struct kvm_vcpu *vcpu) avic_handle_ldr_update(vcpu); } -static struct kvm_x86_ops svm_x86_ops = { +static struct kvm_x86_ops svm_x86_ops __ro_after_init = { .cpu_has_kvm_support = has_svm, .disabled_by_bios = is_disabled, .hardware_setup = svm_hardware_setup, diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c index a45d8580f91e..87eaa6bfc26a 100644 --- a/arch/x86/kvm/vmx.c +++ b/arch/x86/kvm/vmx.c @@ -11175,7 +11175,7 @@ static void vmx_setup_mce(struct kvm_vcpu *vcpu) ~FEATURE_CONTROL_LMCE; } -static struct kvm_x86_ops vmx_x86_ops = { +static struct kvm_x86_ops vmx_x86_ops __ro_after_init = { .cpu_has_kvm_support = cpu_has_kvm_support, .disabled_by_bios = vmx_disabled_by_bios, .hardware_setup = hardware_setup, diff --git a/arch/x86/pci/pcbios.c b/arch/x86/pci/pcbios.c index 9770e55e768f..1d97cea3b3a4 100644 --- a/arch/x86/pci/pcbios.c +++ b/arch/x86/pci/pcbios.c @@ -120,9 +120,12 @@ static unsigned long __init bios32_service(unsigned long service) static struct { unsigned long address; unsigned short segment; -} pci_indirect = { 0, __KERNEL_CS }; +} pci_indirect __ro_after_init = { + .address = 0, + .segment = __KERNEL_CS, +}; -static int pci_bios_present; +static int pci_bios_present __ro_after_init; static int __init check_pcibios(void) { -- GitLab