diff options
75 files changed, 760 insertions, 113 deletions
diff --git a/Makefile b/Makefile index 70bfa5067c87..f03888cdba4e 100644 --- a/Makefile +++ b/Makefile @@ -924,6 +924,23 @@ KBUILD_AFLAGS += -fno-lto export CC_FLAGS_LTO endif +ifdef CONFIG_CFI_CLANG +CC_FLAGS_CFI := -fsanitize=cfi \ + -fsanitize-cfi-cross-dso \ + -fno-sanitize-cfi-canonical-jump-tables \ + -fno-sanitize-trap=cfi \ + -fno-sanitize-blacklist + +ifdef CONFIG_CFI_PERMISSIVE +CC_FLAGS_CFI += -fsanitize-recover=cfi +endif + +# If LTO flags are filtered out, we must also filter out CFI. +CC_FLAGS_LTO += $(CC_FLAGS_CFI) +KBUILD_CFLAGS += $(CC_FLAGS_CFI) +export CC_FLAGS_CFI +endif + ifdef CONFIG_DEBUG_FORCE_FUNCTION_ALIGN_32B KBUILD_CFLAGS += -falign-functions=32 endif diff --git a/arch/Kconfig b/arch/Kconfig index 6b11c825fc36..5bc98d28a6e0 100644 --- a/arch/Kconfig +++ b/arch/Kconfig @@ -692,6 +692,51 @@ config LTO_CLANG_THIN If unsure, say Y. endchoice +config ARCH_SUPPORTS_CFI_CLANG + bool + help + An architecture should select this option if it can support Clang's + Control-Flow Integrity (CFI) checking. + +config CFI_CLANG + bool "Use Clang's Control Flow Integrity (CFI)" + depends on LTO_CLANG && ARCH_SUPPORTS_CFI_CLANG + # Clang >= 12: + # - https://bugs.llvm.org/show_bug.cgi?id=46258 + # - https://bugs.llvm.org/show_bug.cgi?id=47479 + depends on CLANG_VERSION >= 120000 + select KALLSYMS + help + This option enables Clang’s forward-edge Control Flow Integrity + (CFI) checking, where the compiler injects a runtime check to each + indirect function call to ensure the target is a valid function with + the correct static type. This restricts possible call targets and + makes it more difficult for an attacker to exploit bugs that allow + the modification of stored function pointers. More information can be + found from Clang's documentation: + + https://clang.llvm.org/docs/ControlFlowIntegrity.html + +config CFI_CLANG_SHADOW + bool "Use CFI shadow to speed up cross-module checks" + default y + depends on CFI_CLANG && MODULES + help + If you select this option, the kernel builds a fast look-up table of + CFI check functions in loaded modules to reduce performance overhead. + + If unsure, say Y. + +config CFI_PERMISSIVE + bool "Use CFI in permissive mode" + depends on CFI_CLANG + help + When selected, Control Flow Integrity (CFI) violations result in a + warning instead of a kernel panic. This option should only be used + for finding indirect call type mismatches during development. + + If unsure, say N. + config HAVE_ARCH_WITHIN_STACK_FRAMES bool help diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index 406b42c05ee1..ef5c7ffa7f55 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -75,6 +75,7 @@ config ARM64 select ARCH_SUPPORTS_SHADOW_CALL_STACK if CC_HAVE_SHADOW_CALL_STACK select ARCH_SUPPORTS_LTO_CLANG if CPU_LITTLE_ENDIAN select ARCH_SUPPORTS_LTO_CLANG_THIN + select ARCH_SUPPORTS_CFI_CLANG select ARCH_SUPPORTS_ATOMIC_RMW select ARCH_SUPPORTS_INT128 if CC_HAS_INT128 && (GCC_VERSION >= 50000 || CC_IS_CLANG) select ARCH_SUPPORTS_NUMA_BALANCING diff --git a/arch/arm64/include/asm/memory.h b/arch/arm64/include/asm/memory.h index b943879c1c24..e6c7417bfb92 100644 --- a/arch/arm64/include/asm/memory.h +++ b/arch/arm64/include/asm/memory.h @@ -323,6 +323,22 @@ static inline void *phys_to_virt(phys_addr_t x) #define virt_to_pfn(x) __phys_to_pfn(__virt_to_phys((unsigned long)(x))) #define sym_to_pfn(x) __phys_to_pfn(__pa_symbol(x)) +#ifdef CONFIG_CFI_CLANG +/* + * With CONFIG_CFI_CLANG, the compiler replaces function address + * references with the address of the function's CFI jump table + * entry. The function_nocfi macro always returns the address of the + * actual function instead. + */ +#define function_nocfi(x) ({ \ + void *addr; \ + asm("adrp %0, " __stringify(x) "\n\t" \ + "add %0, %0, :lo12:" __stringify(x) \ + : "=r" (addr)); \ + addr; \ +}) +#endif + /* * virt_to_page(x) convert a _valid_ virtual address to struct page * * virt_addr_valid(x) indicates whether a virtual address is valid diff --git a/arch/arm64/include/asm/mmu_context.h b/arch/arm64/include/asm/mmu_context.h index bd02e99b1a4c..d3cef9133539 100644 --- a/arch/arm64/include/asm/mmu_context.h +++ b/arch/arm64/include/asm/mmu_context.h @@ -119,7 +119,7 @@ static inline void cpu_install_idmap(void) * Atomically replaces the active TTBR1_EL1 PGD with a new VA-compatible PGD, * avoiding the possibility of conflicting TLB entries being allocated. */ -static inline void cpu_replace_ttbr1(pgd_t *pgdp) +static inline void __nocfi cpu_replace_ttbr1(pgd_t *pgdp) { typedef void (ttbr_replace_func)(phys_addr_t); extern ttbr_replace_func idmap_cpu_replace_ttbr1; @@ -140,7 +140,7 @@ static inline void cpu_replace_ttbr1(pgd_t *pgdp) ttbr1 |= TTBR_CNP_BIT; } - replace_phys = (void *)__pa_symbol(idmap_cpu_replace_ttbr1); + replace_phys = (void *)__pa_symbol(function_nocfi(idmap_cpu_replace_ttbr1)); cpu_install_idmap(); replace_phys(ttbr1); diff --git a/arch/arm64/kernel/acpi_parking_protocol.c b/arch/arm64/kernel/acpi_parking_protocol.c index e7c941d8340d..bfeeb5319abf 100644 --- a/arch/arm64/kernel/acpi_parking_protocol.c +++ b/arch/arm64/kernel/acpi_parking_protocol.c @@ -99,7 +99,8 @@ static int acpi_parking_protocol_cpu_boot(unsigned int cpu) * that read this address need to convert this address to the * Boot-Loader's endianness before jumping. */ - writeq_relaxed(__pa_symbol(secondary_entry), &mailbox->entry_point); + writeq_relaxed(__pa_symbol(function_nocfi(secondary_entry)), + &mailbox->entry_point); writel_relaxed(cpu_entry->gic_cpu_id, &mailbox->cpu_id); arch_send_wakeup_ipi_mask(cpumask_of(cpu)); diff --git a/arch/arm64/kernel/alternative.c b/arch/arm64/kernel/alternative.c index 1184c44ea2c7..abc84636af07 100644 --- a/arch/arm64/kernel/alternative.c +++ b/arch/arm64/kernel/alternative.c @@ -133,8 +133,8 @@ static void clean_dcache_range_nopatch(u64 start, u64 end) } while (cur += d_size, cur < end); } -static void __apply_alternatives(void *alt_region, bool is_module, - unsigned long *feature_mask) +static void __nocfi __apply_alternatives(void *alt_region, bool is_module, + unsigned long *feature_mask) { struct alt_instr *alt; struct alt_region *region = alt_region; diff --git a/arch/arm64/kernel/cpu-reset.h b/arch/arm64/kernel/cpu-reset.h index ed50e9587ad8..9a7b1262ef17 100644 --- a/arch/arm64/kernel/cpu-reset.h +++ b/arch/arm64/kernel/cpu-reset.h @@ -13,16 +13,16 @@ void __cpu_soft_restart(unsigned long el2_switch, unsigned long entry, unsigned long arg0, unsigned long arg1, unsigned long arg2); -static inline void __noreturn cpu_soft_restart(unsigned long entry, - unsigned long arg0, - unsigned long arg1, - unsigned long arg2) +static inline void __noreturn __nocfi cpu_soft_restart(unsigned long entry, + unsigned long arg0, + unsigned long arg1, + unsigned long arg2) { typeof(__cpu_soft_restart) *restart; unsigned long el2_switch = !is_kernel_in_hyp_mode() && is_hyp_mode_available(); - restart = (void *)__pa_symbol(__cpu_soft_restart); + restart = (void *)__pa_symbol(function_nocfi(__cpu_soft_restart)); cpu_install_idmap(); restart(el2_switch, entry, arg0, arg1, arg2); diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c index 76c60b3cda53..30c82d38c189 100644 --- a/arch/arm64/kernel/cpufeature.c +++ b/arch/arm64/kernel/cpufeature.c @@ -1451,7 +1451,7 @@ static bool unmap_kernel_at_el0(const struct arm64_cpu_capabilities *entry, } #ifdef CONFIG_UNMAP_KERNEL_AT_EL0 -static void +static void __nocfi kpti_install_ng_mappings(const struct arm64_cpu_capabilities *__unused) { typedef void (kpti_remap_fn)(int, int, phys_addr_t); @@ -1468,7 +1468,7 @@ kpti_install_ng_mappings(const struct arm64_cpu_capabilities *__unused) if (arm64_use_ng_mappings) return; - remap_fn = (void *)__pa_symbol(idmap_kpti_install_ng_mappings); + remap_fn = (void *)__pa_symbol(function_nocfi(idmap_kpti_install_ng_mappings)); cpu_install_idmap(); remap_fn(cpu, num_online_cpus(), __pa_symbol(swapper_pg_dir)); diff --git a/arch/arm64/kernel/ftrace.c b/arch/arm64/kernel/ftrace.c index 86a5cf9bc19a..b5d3ddaf69d9 100644 --- a/arch/arm64/kernel/ftrace.c +++ b/arch/arm64/kernel/ftrace.c @@ -55,7 +55,7 @@ int ftrace_update_ftrace_func(ftrace_func_t func) unsigned long pc; u32 new; - pc = (unsigned long)&ftrace_call; + pc = (unsigned long)function_nocfi(ftrace_call); new = aarch64_insn_gen_branch_imm(pc, (unsigned long)func, AARCH64_INSN_BRANCH_LINK); diff --git a/arch/arm64/kernel/psci.c b/arch/arm64/kernel/psci.c index 62d2bda7adb8..ab7f4c476104 100644 --- a/arch/arm64/kernel/psci.c +++ b/arch/arm64/kernel/psci.c @@ -38,7 +38,8 @@ static int __init cpu_psci_cpu_prepare(unsigned int cpu) static int cpu_psci_cpu_boot(unsigned int cpu) { - int err = psci_ops.cpu_on(cpu_logical_map(cpu), __pa_symbol(secondary_entry)); + phys_addr_t pa_secondary_entry = __pa_symbol(function_nocfi(secondary_entry)); + int err = psci_ops.cpu_on(cpu_logical_map(cpu), pa_secondary_entry); if (err) pr_err("failed to boot CPU%d (%d)\n", cpu, err); diff --git a/arch/arm64/kernel/smp_spin_table.c b/arch/arm64/kernel/smp_spin_table.c index 056772c26098..c45a83512805 100644 --- a/arch/arm64/kernel/smp_spin_table.c +++ b/arch/arm64/kernel/smp_spin_table.c @@ -66,6 +66,7 @@ static int smp_spin_table_cpu_init(unsigned int cpu) static int smp_spin_table_cpu_prepare(unsigned int cpu) { __le64 __iomem *release_addr; + phys_addr_t pa_holding_pen = __pa_symbol(function_nocfi(secondary_holding_pen)); if (!cpu_release_addr[cpu]) return -ENODEV; @@ -88,7 +89,7 @@ static int smp_spin_table_cpu_prepare(unsigned int cpu) * boot-loader's endianness before jumping. This is mandated by * the boot protocol. */ - writeq_relaxed(__pa_symbol(secondary_holding_pen), release_addr); + writeq_relaxed(pa_holding_pen, release_addr); __flush_dcache_area((__force void *)release_addr, sizeof(*release_addr)); diff --git a/arch/arm64/kvm/hyp/nvhe/Makefile b/arch/arm64/kvm/hyp/nvhe/Makefile index a6707df4f6c0..fb24a0f022ad 100644 --- a/arch/arm64/kvm/hyp/nvhe/Makefile +++ b/arch/arm64/kvm/hyp/nvhe/Makefile @@ -75,9 +75,9 @@ quiet_cmd_hyprel = HYPREL $@ quiet_cmd_hypcopy = HYPCOPY $@ cmd_hypcopy = $(OBJCOPY) --prefix-symbols=__kvm_nvhe_ $< $@ -# Remove ftrace and Shadow Call Stack CFLAGS. -# This is equivalent to the 'notrace' and '__noscs' annotations. -KBUILD_CFLAGS := $(filter-out $(CC_FLAGS_FTRACE) $(CC_FLAGS_SCS), $(KBUILD_CFLAGS)) +# Remove ftrace, Shadow Call Stack, and CFI CFLAGS. +# This is equivalent to the 'notrace', '__noscs', and '__nocfi' annotations. +KBUILD_CFLAGS := $(filter-out $(CC_FLAGS_FTRACE) $(CC_FLAGS_SCS) $(CC_FLAGS_CFI), $(KBUILD_CFLAGS)) # KVM nVHE code is run at a different exception code with a different map, so # compiler instrumentation that inserts callbacks or checks into the code may diff --git a/arch/arm64/kvm/vgic/vgic-its.c b/arch/arm64/kvm/vgic/vgic-its.c index 40cbaca81333..b9518f94bd43 100644 --- a/arch/arm64/kvm/vgic/vgic-its.c +++ b/arch/arm64/kvm/vgic/vgic-its.c @@ -2190,8 +2190,8 @@ static int vgic_its_restore_ite(struct vgic_its *its, u32 event_id, return offset; } -static int vgic_its_ite_cmp(void *priv, struct list_head *a, - struct list_head *b) +static int vgic_its_ite_cmp(void *priv, const struct list_head *a, + const struct list_head *b) { struct its_ite *itea = container_of(a, struct its_ite, ite_list); struct its_ite *iteb = container_of(b, struct its_ite, ite_list); @@ -2329,8 +2329,8 @@ static int vgic_its_restore_dte(struct vgic_its *its, u32 id, return offset; } -static int vgic_its_device_cmp(void *priv, struct list_head *a, - struct list_head *b) +static int vgic_its_device_cmp(void *priv, const struct list_head *a, + const struct list_head *b) { struct its_device *deva = container_of(a, struct its_device, dev_list); struct its_device *devb = container_of(b, struct its_device, dev_list); diff --git a/arch/arm64/kvm/vgic/vgic.c b/arch/arm64/kvm/vgic/vgic.c index 1c597c9885fa..15b666200f0b 100644 --- a/arch/arm64/kvm/vgic/vgic.c +++ b/arch/arm64/kvm/vgic/vgic.c @@ -255,7 +255,8 @@ static struct kvm_vcpu *vgic_target_oracle(struct vgic_irq *irq) * Return negative if "a" sorts before "b", 0 to preserve order, and positive * to sort "b" before "a". */ -static int vgic_irq_cmp(void *priv, struct list_head *a, struct list_head *b) +static int vgic_irq_cmp(void *priv, const struct list_head *a, + const struct list_head *b) { struct vgic_irq *irqa = container_of(a, struct vgic_irq, ap_list); struct vgic_irq *irqb = container_of(b, struct vgic_irq, ap_list); diff --git a/block/blk-mq-sched.c b/block/blk-mq-sched.c index e1e997af89a0..3ebd6f10f728 100644 --- a/block/blk-mq-sched.c +++ b/block/blk-mq-sched.c @@ -75,7 +75,8 @@ void blk_mq_sched_restart(struct blk_mq_hw_ctx *hctx) blk_mq_run_hw_queue(hctx, true); } -static int sched_rq_cmp(void *priv, struct list_head *a, struct list_head *b) +static int sched_rq_cmp(void *priv, const struct list_head *a, + const struct list_head *b) { struct request *rqa = container_of(a, struct request, queuelist); struct request *rqb = container_of(b, struct request, queuelist); diff --git a/block/blk-mq.c b/block/blk-mq.c index d4d7c1caa439..4e3a70ab5be1 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -1895,7 +1895,8 @@ void blk_mq_insert_requests(struct blk_mq_hw_ctx *hctx, struct blk_mq_ctx *ctx, spin_unlock(&ctx->lock); } -static int plug_rq_cmp(void *priv, struct list_head *a, struct list_head *b) +static int plug_rq_cmp(void *priv, const struct list_head *a, + const struct list_head *b) { struct request *rqa = container_of(a, struct request, queuelist); struct request *rqb = container_of(b, struct request, queuelist); diff --git a/drivers/acpi/nfit/core.c b/drivers/acpi/nfit/core.c index 09b05f720b25..958aaac869e8 100644 --- a/drivers/acpi/nfit/core.c +++ b/drivers/acpi/nfit/core.c @@ -1195,7 +1195,8 @@ static int __nfit_mem_init(struct acpi_nfit_desc *acpi_desc, return 0; } -static int nfit_mem_cmp(void *priv, struct list_head *_a, struct list_head *_b) +static int nfit_mem_cmp(void *priv, const struct list_head *_a, + const struct list_head *_b) { struct nfit_mem *a = container_of(_a, typeof(*a), list); struct nfit_mem *b = container_of(_b, typeof(*b), list); diff --git a/drivers/acpi/numa/hmat.c b/drivers/acpi/numa/hmat.c index a84d85d8333c..c3d783aca196 100644 --- a/drivers/acpi/numa/hmat.c +++ b/drivers/acpi/numa/hmat.c @@ -558,7 +558,8 @@ static bool hmat_update_best(u8 type, u32 value, u32 *best) return updated; } -static int initiator_cmp(void *priv, struct list_head *a, struct list_head *b) +static int initiator_cmp(void *priv, const struct list_head *a, + const struct list_head *b) { struct memory_initiator *ia; struct memory_initiator *ib; diff --git a/drivers/clk/keystone/sci-clk.c b/drivers/clk/keystone/sci-clk.c index aaf31abe1c8f..7e1b136e71ae 100644 --- a/drivers/clk/keystone/sci-clk.c +++ b/drivers/clk/keystone/sci-clk.c @@ -503,8 +503,8 @@ static int ti_sci_scan_clocks_from_fw(struct sci_clk_provider *provider) #else -static int _cmp_sci_clk_list(void *priv, struct list_head *a, - struct list_head *b) +static int _cmp_sci_clk_list(void *priv, const struct list_head *a, + const struct list_head *b) { struct sci_clk *ca = container_of(a, struct sci_clk, node); struct sci_clk *cb = container_of(b, struct sci_clk, node); diff --git a/drivers/firmware/psci/psci.c b/drivers/firmware/psci/psci.c index f5fc429cae3f..64344e84bd63 100644 --- a/drivers/firmware/psci/psci.c +++ b/drivers/firmware/psci/psci.c @@ -325,8 +325,9 @@ static int __init psci_features(u32 psci_func_id) static int psci_suspend_finisher(unsigned long state) { u32 power_state = state; + phys_addr_t pa_cpu_resume = __pa_symbol(function_nocfi(cpu_resume)); - return psci_ops.cpu_suspend(power_state, __pa_symbol(cpu_resume)); + return psci_ops.cpu_suspend(power_state, pa_cpu_resume); } int psci_cpu_suspend_enter(u32 state) @@ -344,8 +345,10 @@ int psci_cpu_suspend_enter(u32 state) static int psci_system_suspend(unsigned long unused) { + phys_addr_t pa_cpu_resume = __pa_symbol(function_nocfi(cpu_resume)); + return invoke_psci_fn(PSCI_FN_NATIVE(1_0, SYSTEM_SUSPEND), - __pa_symbol(cpu_resume), 0, 0); + pa_cpu_resume, 0, 0); } static int psci_system_suspend_enter(suspend_state_t state) diff --git a/drivers/gpu/drm/drm_modes.c b/drivers/gpu/drm/drm_modes.c index 1ac67d4505e0..6662d0457ad6 100644 --- a/drivers/gpu/drm/drm_modes.c +++ b/drivers/gpu/drm/drm_modes.c @@ -1290,7 +1290,8 @@ EXPORT_SYMBOL(drm_mode_prune_invalid); * Negative if @lh_a is better than @lh_b, zero if they're equivalent, or * positive if @lh_b is better than @lh_a. */ -static int drm_mode_compare(void *priv, struct list_head *lh_a, struct list_head *lh_b) +static int drm_mode_compare(void *priv, const struct list_head *lh_a, + const struct list_head *lh_b) { struct drm_display_mode *a = list_entry(lh_a, struct drm_display_mode, head); struct drm_display_mode *b = list_entry(lh_b, struct drm_display_mode, head); diff --git a/drivers/gpu/drm/i915/gt/intel_engine_user.c b/drivers/gpu/drm/i915/gt/intel_engine_user.c index 34e6096f196e..da21d2a10cc9 100644 --- a/drivers/gpu/drm/i915/gt/intel_engine_user.c +++ b/drivers/gpu/drm/i915/gt/intel_engine_user.c @@ -49,7 +49,8 @@ static const u8 uabi_classes[] = { [VIDEO_ENHANCEMENT_CLASS] = I915_ENGINE_CLASS_VIDEO_ENHANCE, }; -static int engine_cmp(void *priv, struct list_head *A, struct list_head *B) +static int engine_cmp(void *priv, const struct list_head *A, + const struct list_head *B) { const struct intel_engine_cs *a = container_of((struct rb_node *)A, typeof(*a), uabi_node); diff --git a/drivers/gpu/drm/i915/gvt/debugfs.c b/drivers/gpu/drm/i915/gvt/debugfs.c index 62e6a14ad58e..9f1c209d9251 100644 --- a/drivers/gpu/drm/i915/gvt/debugfs.c +++ b/drivers/gpu/drm/i915/gvt/debugfs.c @@ -41,7 +41,7 @@ struct diff_mmio { /* Compare two diff_mmio items. */ static int mmio_offset_compare(void *priv, - struct list_head *a, struct list_head *b) + const struct list_head *a, const struct list_head *b) { struct diff_mmio *ma; struct diff_mmio *mb; diff --git a/drivers/gpu/drm/i915/selftests/i915_gem_gtt.c b/drivers/gpu/drm/i915/selftests/i915_gem_gtt.c index c1adea8765a9..52b9c39e0155 100644 --- a/drivers/gpu/drm/i915/selftests/i915_gem_gtt.c +++ b/drivers/gpu/drm/i915/selftests/i915_gem_gtt.c @@ -1076,7 +1076,8 @@ static int igt_ppgtt_shrink_boom(void *arg) return exercise_ppgtt(arg, shrink_boom); } -static int sort_holes(void *priv, struct list_head *A, struct list_head *B) +static int sort_holes(void *priv, const struct list_head *A, + const struct list_head *B) { struct drm_mm_node *a = list_entry(A, typeof(*a), hole_stack); struct drm_mm_node *b = list_entry(B, typeof(*b), hole_stack); diff --git a/drivers/gpu/drm/radeon/radeon_cs.c b/drivers/gpu/drm/radeon/radeon_cs.c index 35e937d39b51..1a5c3db1d53b 100644 --- a/drivers/gpu/drm/radeon/radeon_cs.c +++ b/drivers/gpu/drm/radeon/radeon_cs.c @@ -393,8 +393,8 @@ int radeon_cs_parser_init(struct radeon_cs_parser *p, void *data) return 0; } -static int cmp_size_smaller_first(void *priv, struct list_head *a, - struct list_head *b) +static int cmp_size_smaller_first(void *priv, const struct list_head *a, + const struct list_head *b) { struct radeon_bo_list *la = list_entry(a, struct radeon_bo_list, tv.head); struct radeon_bo_list *lb = list_entry(b, struct radeon_bo_list, tv.head); diff --git a/drivers/infiniband/hw/usnic/usnic_uiom_interval_tree.c b/drivers/infiniband/hw/usnic/usnic_uiom_interval_tree.c index d399523206c7..29d71267af78 100644 --- a/drivers/infiniband/hw/usnic/usnic_uiom_interval_tree.c +++ b/drivers/infiniband/hw/usnic/usnic_uiom_interval_tree.c @@ -83,7 +83,8 @@ usnic_uiom_interval_node_alloc(long int start, long int last, int ref_cnt, return interval; } -static int interval_cmp(void *priv, struct list_head *a, struct list_head *b) +static int interval_cmp(void *priv, const struct list_head *a, + const struct list_head *b) { struct usnic_uiom_interval_node *node_a, *node_b; diff --git a/drivers/interconnect/qcom/bcm-voter.c b/drivers/interconnect/qcom/bcm-voter.c index 1cc565bce2f4..d1591a28b743 100644 --- a/drivers/interconnect/qcom/bcm-voter.c +++ b/drivers/interconnect/qcom/bcm-voter.c @@ -39,7 +39,7 @@ struct bcm_voter { u32 tcs_wait; }; -static int cmp_vcd(void *priv, struct list_head *a, struct list_head *b) +static int cmp_vcd(void *priv, const struct list_head *a, const struct list_head *b) { const struct qcom_icc_bcm *bcm_a = list_entry(a, struct qcom_icc_bcm, list); const struct qcom_icc_bcm *bcm_b = list_entry(b, struct qcom_icc_bcm, list); diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c index 5d57a5bd171f..841e1c1aa5e6 100644 --- a/drivers/md/raid5.c +++ b/drivers/md/raid5.c @@ -953,7 +953,8 @@ static void dispatch_bio_list(struct bio_list *tmp) submit_bio_noacct(bio); } -static int cmp_stripe(void *priv, struct list_head *a, struct list_head *b) +static int cmp_stripe(void *priv, const struct list_head *a, + const struct list_head *b) { const struct r5pending_data *da = list_entry(a, struct r5pending_data, sibling); diff --git a/drivers/misc/lkdtm/usercopy.c b/drivers/misc/lkdtm/usercopy.c index 109e8d4302c1..15d220ef35a5 100644 --- a/drivers/misc/lkdtm/usercopy.c +++ b/drivers/misc/lkdtm/usercopy.c @@ -314,7 +314,7 @@ void lkdtm_USERCOPY_KERNEL(void) pr_info("attempting bad copy_to_user from kernel text: %px\n", vm_mmap); - if (copy_to_user((void __user *)user_addr, vm_mmap, + if (copy_to_user((void __user *)user_addr, function_nocfi(vm_mmap), unconst + PAGE_SIZE)) { pr_warn("copy_to_user failed, but lacked Oops\n"); goto free_user; diff --git a/drivers/misc/sram.c b/drivers/misc/sram.c index 6c1a23cb3e8c..202bf951e909 100644 --- a/drivers/misc/sram.c +++ b/drivers/misc/sram.c @@ -144,8 +144,8 @@ static void sram_free_partitions(struct sram_dev *sram) } } -static int sram_reserve_cmp(void *priv, struct list_head *a, - struct list_head *b) +static int sram_reserve_cmp(void *priv, const struct list_head *a, + const struct list_head *b) { struct sram_reserve *ra = list_entry(a, struct sram_reserve, list); struct sram_reserve *rb = list_entry(b, struct sram_reserve, list); diff --git a/drivers/nvme/host/core.c b/drivers/nvme/host/core.c index 0896e21642be..5eaaa51a5e30 100644 --- a/drivers/nvme/host/core.c +++ b/drivers/nvme/host/core.c @@ -3855,7 +3855,8 @@ out_unlock: return ret; } -static int ns_cmp(void *priv, struct list_head *a, struct list_head *b) +static int ns_cmp(void *priv, const struct list_head *a, + const struct list_head *b) { struct nvme_ns *nsa = container_of(a, struct nvme_ns, list); struct nvme_ns *nsb = container_of(b, struct nvme_ns, list); diff --git a/drivers/pci/controller/cadence/pcie-cadence-host.c b/drivers/pci/controller/cadence/pcie-cadence-host.c index 73dcf8cf98fb..ae1c55503513 100644 --- a/drivers/pci/controller/cadence/pcie-cadence-host.c +++ b/drivers/pci/controller/cadence/pcie-cadence-host.c @@ -345,7 +345,8 @@ static int cdns_pcie_host_bar_config(struct cdns_pcie_rc *rc, return 0; } -static int cdns_pcie_host_dma_ranges_cmp(void *priv, struct list_head *a, struct list_head *b) +static int cdns_pcie_host_dma_ranges_cmp(void *priv, const struct list_head *a, + const struct list_head *b) { struct resource_entry *entry1, *entry2; diff --git a/drivers/spi/spi-loopback-test.c b/drivers/spi/spi-loopback-test.c index df981e55c24c..f1cf2232f0b5 100644 --- a/drivers/spi/spi-loopback-test.c +++ b/drivers/spi/spi-loopback-test.c @@ -454,7 +454,8 @@ struct rx_ranges { u8 *end; }; -static int rx_ranges_cmp(void *priv, struct list_head *a, struct list_head *b) +static int rx_ranges_cmp(void *priv, const struct list_head *a, + const struct list_head *b) { struct rx_ranges *rx_a = list_entry(a, struct rx_ranges, list); struct rx_ranges *rx_b = list_entry(b, struct rx_ranges, list); diff --git a/fs/btrfs/raid56.c b/fs/btrfs/raid56.c index bb768c309bc3..244d499ebc72 100644 --- a/fs/btrfs/raid56.c +++ b/fs/btrfs/raid56.c @@ -1633,7 +1633,8 @@ struct btrfs_plug_cb { /* * rbios on the plug list are sorted for easier merging. */ -static int plug_cmp(void *priv, struct list_head *a, struct list_head *b) +static int plug_cmp(void *priv, const struct list_head *a, + const struct list_head *b) { struct btrfs_raid_bio *ra = container_of(a, struct btrfs_raid_bio, plug_list); diff --git a/fs/btrfs/tree-log.c b/fs/btrfs/tree-log.c index c1353b84ae54..f67721d82e5d 100644 --- a/fs/btrfs/tree-log.c +++ b/fs/btrfs/tree-log.c @@ -4138,7 +4138,8 @@ static noinline int copy_items(struct btrfs_trans_handle *trans, return ret; } -static int extent_cmp(void *priv, struct list_head *a, struct list_head *b) +static int extent_cmp(void *priv, const struct list_head *a, + const struct list_head *b) { struct extent_map *em1, *em2; diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c index 77cdb75acc15..9a1ead0c4a31 100644 --- a/fs/btrfs/volumes.c +++ b/fs/btrfs/volumes.c @@ -1224,7 +1224,8 @@ static int open_fs_devices(struct btrfs_fs_devices *fs_devices, return 0; } -static int devid_cmp(void *priv, struct list_head *a, struct list_head *b) +static int devid_cmp(void *priv, const struct list_head *a, + const struct list_head *b) { struct btrfs_device *dev1, *dev2; diff --git a/fs/ext4/fsmap.c b/fs/ext4/fsmap.c index 4c2a9fe30067..4493ef0c715e 100644 --- a/fs/ext4/fsmap.c +++ b/fs/ext4/fsmap.c @@ -354,8 +354,8 @@ static unsigned int ext4_getfsmap_find_sb(struct super_block *sb, /* Compare two fsmap items. */ static int ext4_getfsmap_compare(void *priv, - struct list_head *a, - struct list_head *b) + const struct list_head *a, + const struct list_head *b) { struct ext4_fsmap *fa; struct ext4_fsmap *fb; diff --git a/fs/gfs2/glock.c b/fs/gfs2/glock.c index 9567520d79f7..c06a6cdf05de 100644 --- a/fs/gfs2/glock.c +++ b/fs/gfs2/glock.c @@ -1732,7 +1732,8 @@ void gfs2_glock_complete(struct gfs2_glock *gl, int ret) spin_unlock(&gl->gl_lockref.lock); } -static int glock_cmp(void *priv, struct list_head *a, struct list_head *b) +static int glock_cmp(void *priv, const struct list_head *a, + const struct list_head *b) { struct gfs2_glock *gla, *glb; diff --git a/fs/gfs2/log.c b/fs/gfs2/log.c index 6410281546f9..88649b43fcff 100644 --- a/fs/gfs2/log.c +++ b/fs/gfs2/log.c @@ -695,7 +695,7 @@ void log_flush_wait(struct gfs2_sbd *sdp) } } -static int ip_cmp(void *priv, struct list_head *a, struct list_head *b) +static int ip_cmp(void *priv, const struct list_head *a, const struct list_head *b) { struct gfs2_inode *ipa, *ipb; diff --git a/fs/gfs2/lops.c b/fs/gfs2/lops.c index a82f4747aa8d..b4809967efc6 100644 --- a/fs/gfs2/lops.c +++ b/fs/gfs2/lops.c @@ -634,7 +634,8 @@ static void gfs2_check_magic(struct buffer_head *bh) kunmap_atomic(kaddr); } -static int blocknr_cmp(void *priv, struct list_head *a, struct list_head *b) +static int blocknr_cmp(void *priv, const struct list_head *a, + const struct list_head *b) { struct gfs2_bufdata *bda, *bdb; diff --git a/fs/iomap/buffered-io.c b/fs/iomap/buffered-io.c index 414769a6ad11..0129e6bab985 100644 --- a/fs/iomap/buffered-io.c +++ b/fs/iomap/buffered-io.c @@ -1155,7 +1155,8 @@ iomap_ioend_try_merge(struct iomap_ioend *ioend, struct list_head *more_ioends, EXPORT_SYMBOL_GPL(iomap_ioend_try_merge); static int -iomap_ioend_compare(void *priv, struct list_head *a, struct list_head *b) +iomap_ioend_compare(void *priv, const struct list_head *a, + const struct list_head *b) { struct iomap_ioend *ia = container_of(a, struct iomap_ioend, io_list); struct iomap_ioend *ib = container_of(b, struct iomap_ioend, io_list); diff --git a/fs/ubifs/gc.c b/fs/ubifs/gc.c index a4aaeea63893..dc3e26e9ed7b 100644 --- a/fs/ubifs/gc.c +++ b/fs/ubifs/gc.c @@ -102,7 +102,8 @@ static int switch_gc_head(struct ubifs_info *c) * This function compares data nodes @a and @b. Returns %1 if @a has greater * inode or block number, and %-1 otherwise. */ -static int data_nodes_cmp(void *priv, struct list_head *a, struct list_head *b) +static int data_nodes_cmp(void *priv, const struct list_head *a, + const struct list_head *b) { ino_t inuma, inumb; struct ubifs_info *c = priv; @@ -145,8 +146,8 @@ static int data_nodes_cmp(void *priv, struct list_head *a, struct list_head *b) * first and sorted by length in descending order. Directory entry nodes go * after inode nodes and are sorted in ascending hash valuer order. */ -static int nondata_nodes_cmp(void *priv, struct list_head *a, - struct list_head *b) +static int nondata_nodes_cmp(void *priv, const struct list_head *a, + const struct list_head *b) { ino_t inuma, inumb; struct ubifs_info *c = priv; diff --git a/fs/ubifs/replay.c b/fs/ubifs/replay.c index 0f8a6a16421b..4d17e5382b74 100644 --- a/fs/ubifs/replay.c +++ b/fs/ubifs/replay.c @@ -298,8 +298,8 @@ static int apply_replay_entry(struct ubifs_info *c, struct replay_entry *r) * entries @a and @b by comparing their sequence numer. Returns %1 if @a has * greater sequence number and %-1 otherwise. */ -static int replay_entries_cmp(void *priv, struct list_head *a, - struct list_head *b) +static int replay_entries_cmp(void *priv, const struct list_head *a, + const struct list_head *b) { struct ubifs_info *c = priv; struct replay_entry *ra, *rb; diff --git a/fs/xfs/scrub/bitmap.c b/fs/xfs/scrub/bitmap.c index f88694f22d05..813b5f219113 100644 --- a/fs/xfs/scrub/bitmap.c +++ b/fs/xfs/scrub/bitmap.c @@ -63,8 +63,8 @@ xbitmap_init( static int xbitmap_range_cmp( void *priv, - struct list_head *a, - struct list_head *b) + const struct list_head *a, + const struct list_head *b) { struct xbitmap_range *ap; struct xbitmap_range *bp; diff --git a/fs/xfs/xfs_bmap_item.c b/fs/xfs/xfs_bmap_item.c index 2344757ede63..e3a691937e92 100644 --- a/fs/xfs/xfs_bmap_item.c +++ b/fs/xfs/xfs_bmap_item.c @@ -265,8 +265,8 @@ xfs_trans_log_finish_bmap_update( static int xfs_bmap_update_diff_items( void *priv, - struct list_head *a, - struct list_head *b) + const struct list_head *a, + const struct list_head *b) { struct xfs_bmap_intent *ba; struct xfs_bmap_intent *bb; diff --git a/fs/xfs/xfs_buf.c b/fs/xfs/xfs_buf.c index 37a1d12762d8..592800c8852f 100644 --- a/fs/xfs/xfs_buf.c +++ b/fs/xfs/xfs_buf.c @@ -2124,9 +2124,9 @@ xfs_buf_delwri_queue( */ static int xfs_buf_cmp( - void *priv, - struct list_head *a, - struct list_head *b) + void *priv, + const struct list_head *a, + const struct list_head *b) { struct xfs_buf *ap = container_of(a, struct xfs_buf, b_list); struct xfs_buf *bp = container_of(b, struct xfs_buf, b_list); diff --git a/fs/xfs/xfs_extent_busy.c b/fs/xfs/xfs_extent_busy.c index ef17c1f6db32..a4075685d9eb 100644 --- a/fs/xfs/xfs_extent_busy.c +++ b/fs/xfs/xfs_extent_busy.c @@ -629,8 +629,8 @@ xfs_extent_busy_wait_all( int xfs_extent_busy_ag_cmp( void *priv, - struct list_head *l1, - struct list_head *l2) + const struct list_head *l1, + const struct list_head *l2) { struct xfs_extent_busy *b1 = container_of(l1, struct xfs_extent_busy, list); diff --git a/fs/xfs/xfs_extent_busy.h b/fs/xfs/xfs_extent_busy.h index 990ab3891971..8aea07100092 100644 --- a/fs/xfs/xfs_extent_busy.h +++ b/fs/xfs/xfs_extent_busy.h @@ -58,7 +58,8 @@ void xfs_extent_busy_wait_all(struct xfs_mount *mp); int -xfs_extent_busy_ag_cmp(void *priv, struct list_head *a, struct list_head *b); +xfs_extent_busy_ag_cmp(void *priv, const struct list_head *a, + const struct list_head *b); static inline void xfs_extent_busy_sort(struct list_head *list) { diff --git a/fs/xfs/xfs_extfree_item.c b/fs/xfs/xfs_extfree_item.c index 93223ebb3372..2424230ca2c3 100644 --- a/fs/xfs/xfs_extfree_item.c +++ b/fs/xfs/xfs_extfree_item.c @@ -397,8 +397,8 @@ xfs_trans_free_extent( static int xfs_extent_free_diff_items( void *priv, - struct list_head *a, - struct list_head *b) + const struct list_head *a, + const struct list_head *b) { struct xfs_mount *mp = priv; struct xfs_extent_free_item *ra; diff --git a/fs/xfs/xfs_refcount_item.c b/fs/xfs/xfs_refcount_item.c index 07ebccbbf4df..746f4eda724c 100644 --- a/fs/xfs/xfs_refcount_item.c +++ b/fs/xfs/xfs_refcount_item.c @@ -269,8 +269,8 @@ xfs_trans_log_finish_refcount_update( static int xfs_refcount_update_diff_items( void *priv, - struct list_head *a, - struct list_head *b) + const struct list_head *a, + const struct list_head *b) { struct xfs_mount *mp = priv; struct xfs_refcount_intent *ra; diff --git a/fs/xfs/xfs_rmap_item.c b/fs/xfs/xfs_rmap_item.c index 49cebd68b672..dc4f0c9f0897 100644 --- a/fs/xfs/xfs_rmap_item.c +++ b/fs/xfs/xfs_rmap_item.c @@ -337,8 +337,8 @@ xfs_trans_log_finish_rmap_update( static int xfs_rmap_update_diff_items( void *priv, - struct list_head *a, - struct list_head *b) + const struct list_head *a, + const struct list_head *b) { struct xfs_mount *mp = priv; struct xfs_rmap_intent *ra; diff --git a/include/asm-generic/bug.h b/include/asm-generic/bug.h index 76a10e0dca9f..b402494883b6 100644 --- a/include/asm-generic/bug.h +++ b/include/asm-generic/bug.h @@ -241,6 +241,22 @@ void __warn(const char *file, int line, void *caller, unsigned taint, # define WARN_ON_SMP(x) ({0;}) #endif +/* + * WARN_ON_FUNCTION_MISMATCH() warns if a value doesn't match a + * function address, and can be useful for catching issues with + * callback functions, for example. + * + * With CONFIG_CFI_CLANG, the warning is disabled because the + * compiler replaces function addresses taken in C code with + * local jump table addresses, which breaks cross-module function + * address equality. + */ +#if defined(CONFIG_CFI_CLANG) && defined(CONFIG_MODULES) +# define WARN_ON_FUNCTION_MISMATCH(x, fn) ({ 0; }) +#else +# define WARN_ON_FUNCTION_MISMATCH(x, fn) WARN_ON_ONCE((x) != (fn)) +#endif + #endif /* __ASSEMBLY__ */ #endif diff --git a/include/asm-generic/vmlinux.lds.h b/include/asm-generic/vmlinux.lds.h index 0331d5d49551..40a9c101565e 100644 --- a/include/asm-generic/vmlinux.lds.h +++ b/include/asm-generic/vmlinux.lds.h @@ -544,6 +544,22 @@ . = ALIGN((align)); \ __end_rodata = .; + +/* + * .text..L.cfi.jumptable.* contain Control-Flow Integrity (CFI) + * jump table entries. + */ +#ifdef CONFIG_CFI_CLANG +#define TEXT_CFI_JT \ + . = ALIGN(PMD_SIZE); \ + __cfi_jt_start = .; \ + *(.text..L.cfi.jumptable .text..L.cfi.jumptable.*) \ + . = ALIGN(PMD_SIZE); \ + __cfi_jt_end = .; +#else +#define TEXT_CFI_JT +#endif + /* * Non-instrumentable text section */ @@ -570,6 +586,7 @@ NOINSTR_TEXT \ *(.text..refcount) \ *(.ref.text) \ + TEXT_CFI_JT \ MEM_KEEP(init.text*) \ MEM_KEEP(exit.text*) \ @@ -974,7 +991,8 @@ * keep any .init_array.* sections. * https://bugs.llvm.org/show_bug.cgi?id=46478 */ -#if defined(CONFIG_GCOV_KERNEL) || defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KCSAN) +#if defined(CONFIG_GCOV_KERNEL) || defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KCSAN) || \ + defined(CONFIG_CFI_CLANG) # ifdef CONFIG_CONSTRUCTORS # define SANITIZER_DISCARDS \ *(.eh_frame) diff --git a/include/linux/bpf.h b/include/linux/bpf.h index fdac0534ce79..00597b0c719c 100644 --- a/include/linux/bpf.h +++ b/include/linux/bpf.h @@ -652,7 +652,7 @@ struct bpf_dispatcher { struct bpf_ksym ksym; }; -static __always_inline unsigned int bpf_dispatcher_nop_func( +static __always_inline __nocfi unsigned int bpf_dispatcher_nop_func( const void *ctx, const struct bpf_insn *insnsi, unsigned int (*bpf_func)(const void *, @@ -680,7 +680,7 @@ void bpf_trampoline_put(struct bpf_trampoline *tr); } #define DEFINE_BPF_DISPATCHER(name) \ - noinline unsigned int bpf_dispatcher_##name##_func( \ + noinline __nocfi unsigned int bpf_dispatcher_##name##_func( \ const void *ctx, \ const struct bpf_insn *insnsi, \ unsigned int (*bpf_func)(const void *, \ diff --git a/include/linux/cfi.h b/include/linux/cfi.h new file mode 100644 index 000000000000..879744aaa6e0 --- /dev/null +++ b/include/linux/cfi.h @@ -0,0 +1,41 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Clang Control Flow Integrity (CFI) support. + * + * Copyright (C) 2021 Google LLC + */ +#ifndef _LINUX_CFI_H +#define _LINUX_CFI_H + +#ifdef CONFIG_CFI_CLANG +typedef void (*cfi_check_fn)(uint64_t id, void *ptr, void *diag); + +/* Compiler-generated function in each module, and the kernel */ +extern void __cfi_check(uint64_t id, void *ptr, void *diag); + +/* + * Force the compiler to generate a CFI jump table entry for a function + * and store the jump table address to __cfi_jt_<function>. + */ +#define __CFI_ADDRESSABLE(fn, __attr) \ + const void *__cfi_jt_ ## fn __visible __attr = (void *)&fn + +#ifdef CONFIG_CFI_CLANG_SHADOW + +extern void cfi_module_add(struct module *mod, unsigned long base_addr); +extern void cfi_module_remove(struct module *mod, unsigned long base_addr); + +#else + +static inline void cfi_module_add(struct module *mod, unsigned long base_addr) {} +static inline void cfi_module_remove(struct module *mod, unsigned long base_addr) {} + +#endif /* CONFIG_CFI_CLANG_SHADOW */ + +#else /* !CONFIG_CFI_CLANG */ + +#define __CFI_ADDRESSABLE(fn, __attr) + +#endif /* CONFIG_CFI_CLANG */ + +#endif /* _LINUX_CFI_H */ diff --git a/include/linux/compiler-clang.h b/include/linux/compiler-clang.h index d217c382b02d..adbe76b203e2 100644 --- a/include/linux/compiler-clang.h +++ b/include/linux/compiler-clang.h @@ -61,3 +61,6 @@ #if __has_feature(shadow_call_stack) # define __noscs __attribute__((__no_sanitize__("shadow-call-stack"))) #endif + +#define __nocfi __attribute__((__no_sanitize__("cfi"))) +#define __cficanonical __attribute__((__cfi_canonical_jump_table__)) diff --git a/include/linux/compiler_types.h b/include/linux/compiler_types.h index e5dd5a4ae946..d29bda7f6ebd 100644 --- a/include/linux/compiler_types.h +++ b/include/linux/compiler_types.h @@ -242,6 +242,14 @@ struct ftrace_likely_data { # define __noscs #endif +#ifndef __nocfi +# define __nocfi +#endif + +#ifndef __cficanonical +# define __cficanonical +#endif + #ifndef asm_volatile_goto #define asm_volatile_goto(x...) asm goto(x) #endif diff --git a/include/linux/init.h b/include/linux/init.h index 31f54de58429..045ad1650ed1 100644 --- a/include/linux/init.h +++ b/include/linux/init.h @@ -47,7 +47,7 @@ /* These are for everybody (although not all archs will actually discard it in modules) */ -#define __init __section(".init.text") __cold __latent_entropy __noinitretpoline +#define __init __section(".init.text") __cold __latent_entropy __noinitretpoline __nocfi #define __initdata __section(".init.data") #define __initconst __section(".init.rodata") #define __exitdata __section(".exit.data") @@ -220,8 +220,8 @@ extern bool initcall_debug; __initcall_name(initstub, __iid, id) #define __define_initcall_stub(__stub, fn) \ - int __init __stub(void); \ - int __init __stub(void) \ + int __init __cficanonical __stub(void); \ + int __init __cficanonical __stub(void) \ { \ return fn(); \ } \ diff --git a/include/linux/list_sort.h b/include/linux/list_sort.h index 20f178c24e9d..453105f74e05 100644 --- a/include/linux/list_sort.h +++ b/include/linux/list_sort.h @@ -6,8 +6,9 @@ struct list_head; +typedef int __attribute__((nonnull(2,3))) (*list_cmp_func_t)(void *, + const struct list_head *, const struct list_head *); + __attribute__((nonnull(2,3))) -void list_sort(void *priv, struct list_head *head, - int (*cmp)(void *priv, struct list_head *a, - struct list_head *b)); +void list_sort(void *priv, struct list_head *head, list_cmp_func_t cmp); #endif diff --git a/include/linux/mm.h b/include/linux/mm.h index 616dcaf08d99..06094627f1c1 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -125,6 +125,16 @@ extern int mmap_rnd_compat_bits __read_mostly; #endif /* + * With CONFIG_CFI_CLANG, the compiler replaces function addresses in + * instrumented C code with jump table addresses. Architectures that + * support CFI can define this macro to return the actual function address + * when needed. + */ +#ifndef function_nocfi +#define function_nocfi(x) (x) +#endif + +/* * To prevent common memory management code establishing * a zero page mapping on a read fault. * This macro should be defined within <asm/pgtable.h>. diff --git a/include/linux/module.h b/include/linux/module.h index da4b6fbe8ebe..8100bb477d86 100644 --- a/include/linux/module.h +++ b/include/linux/module.h @@ -26,6 +26,7 @@ #include <linux/tracepoint-defs.h> #include <linux/srcu.h> #include <linux/static_call_types.h> +#include <linux/cfi.h> #include <linux/percpu.h> #include <asm/module.h> @@ -128,13 +129,17 @@ extern void cleanup_module(void); #define module_init(initfn) \ static inline initcall_t __maybe_unused __inittest(void) \ { return initfn; } \ - int init_module(void) __copy(initfn) __attribute__((alias(#initfn))); + int init_module(void) __copy(initfn) \ + __attribute__((alias(#initfn))); \ + __CFI_ADDRESSABLE(init_module, __initdata); /* This is only required if you want to be unloadable. */ #define module_exit(exitfn) \ static inline exitcall_t __maybe_unused __exittest(void) \ { return exitfn; } \ - void cleanup_module(void) __copy(exitfn) __attribute__((alias(#exitfn))); + void cleanup_module(void) __copy(exitfn) \ + __attribute__((alias(#exitfn))); \ + __CFI_ADDRESSABLE(cleanup_module, __exitdata); #endif @@ -376,6 +381,10 @@ struct module { const s32 *crcs; unsigned int num_syms; +#ifdef CONFIG_CFI_CLANG + cfi_check_fn cfi_check; +#endif + /* Kernel parameters. */ #ifdef CONFIG_SYSFS struct mutex param_lock; diff --git a/include/linux/pci.h b/include/linux/pci.h index 86c799c97b77..39684b72db91 100644 --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -1944,8 +1944,8 @@ enum pci_fixup_pass { #ifdef CONFIG_LTO_CLANG #define __DECLARE_PCI_FIXUP_SECTION(sec, name, vendor, device, class, \ class_shift, hook, stub) \ - void stub(struct pci_dev *dev); \ - void stub(struct pci_dev *dev) \ + void __cficanonical stub(struct pci_dev *dev); \ + void __cficanonical stub(struct pci_dev *dev) \ { \ hook(dev); \ } \ diff --git a/init/Kconfig b/init/Kconfig index 5f5c776ef192..5babea38e346 100644 --- a/init/Kconfig +++ b/init/Kconfig @@ -2296,7 +2296,7 @@ endif # MODULES config MODULES_TREE_LOOKUP def_bool y - depends on PERF_EVENTS || TRACING + depends on PERF_EVENTS || TRACING || CFI_CLANG config INIT_ALL_POSSIBLE bool diff --git a/kernel/Makefile b/kernel/Makefile index 320f1f3941b7..e8a6715f38dc 100644 --- a/kernel/Makefile +++ b/kernel/Makefile @@ -41,6 +41,9 @@ KCSAN_SANITIZE_kcov.o := n UBSAN_SANITIZE_kcov.o := n CFLAGS_kcov.o := $(call cc-option, -fno-conserve-stack) -fno-stack-protector +# Don't instrument error handlers +CFLAGS_REMOVE_cfi.o := $(CC_FLAGS_CFI) + obj-y += sched/ obj-y += locking/ obj-y += power/ @@ -111,6 +114,7 @@ obj-$(CONFIG_BPF) += bpf/ obj-$(CONFIG_KCSAN) += kcsan/ obj-$(CONFIG_SHADOW_CALL_STACK) += scs.o obj-$(CONFIG_HAVE_STATIC_CALL_INLINE) += static_call.o +obj-$(CONFIG_CFI_CLANG) += cfi.o obj-$(CONFIG_PERF_EVENTS) += events/ diff --git a/kernel/cfi.c b/kernel/cfi.c new file mode 100644 index 000000000000..e17a56639766 --- /dev/null +++ b/kernel/cfi.c @@ -0,0 +1,329 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Clang Control Flow Integrity (CFI) error and slowpath handling. + * + * Copyright (C) 2021 Google LLC + */ + +#include <linux/hardirq.h> +#include <linux/kallsyms.h> +#include <linux/module.h> +#include <linux/mutex.h> +#include <linux/printk.h> +#include <linux/ratelimit.h> +#include <linux/rcupdate.h> +#include <linux/vmalloc.h> +#include <asm/cacheflush.h> +#include <asm/set_memory.h> + +/* Compiler-defined handler names */ +#ifdef CONFIG_CFI_PERMISSIVE +#define cfi_failure_handler __ubsan_handle_cfi_check_fail +#else +#define cfi_failure_handler __ubsan_handle_cfi_check_fail_abort +#endif + +static inline void handle_cfi_failure(void *ptr) +{ + if (IS_ENABLED(CONFIG_CFI_PERMISSIVE)) + WARN_RATELIMIT(1, "CFI failure (target: %pS):\n", ptr); + else + panic("CFI failure (target: %pS)\n", ptr); +} + +#ifdef CONFIG_MODULES +#ifdef CONFIG_CFI_CLANG_SHADOW +/* + * Index type. A 16-bit index can address at most (2^16)-2 pages (taking + * into account SHADOW_INVALID), i.e. ~256M with 4k pages. + */ +typedef u16 shadow_t; +#define SHADOW_INVALID ((shadow_t)~0UL) + +struct cfi_shadow { + /* Page index for the beginning of the shadow */ + unsigned long base; + /* An array of __cfi_check locations (as indices to the shadow) */ + shadow_t shadow[1]; +} __packed; + +/* + * The shadow covers ~128M from the beginning of the module region. If + * the region is larger, we fall back to __module_address for the rest. + */ +#define __SHADOW_RANGE (_UL(SZ_128M) >> PAGE_SHIFT) + +/* The in-memory size of struct cfi_shadow, always at least one page */ +#define __SHADOW_PAGES ((__SHADOW_RANGE * sizeof(shadow_t)) >> PAGE_SHIFT) +#define SHADOW_PAGES max(1UL, __SHADOW_PAGES) +#define SHADOW_SIZE (SHADOW_PAGES << PAGE_SHIFT) + +/* The actual size of the shadow array, minus metadata */ +#define SHADOW_ARR_SIZE (SHADOW_SIZE - offsetof(struct cfi_shadow, shadow)) +#define SHADOW_ARR_SLOTS (SHADOW_ARR_SIZE / sizeof(shadow_t)) + +static DEFINE_MUTEX(shadow_update_lock); +static struct cfi_shadow __rcu *cfi_shadow __read_mostly; + +/* Returns the index in the shadow for the given address */ +static inline int ptr_to_shadow(const struct cfi_shadow *s, unsigned long ptr) +{ + unsigned long index; + unsigned long page = ptr >> PAGE_SHIFT; + + if (unlikely(page < s->base)) + return -1; /* Outside of module area */ + + index = page - s->base; + + if (index >= SHADOW_ARR_SLOTS) + return -1; /* Cannot be addressed with shadow */ + + return (int)index; +} + +/* Returns the page address for an index in the shadow */ +static inline unsigned long shadow_to_ptr(const struct cfi_shadow *s, + int index) +{ + if (unlikely(index < 0 || index >= SHADOW_ARR_SLOTS)) + return 0; + + return (s->base + index) << PAGE_SHIFT; +} + +/* Returns the __cfi_check function address for the given shadow location */ +static inline unsigned long shadow_to_check_fn(const struct cfi_shadow *s, + int index) +{ + if (unlikely(index < 0 || index >= SHADOW_ARR_SLOTS)) + return 0; + + if (unlikely(s->shadow[index] == SHADOW_INVALID)) + return 0; + + /* __cfi_check is always page aligned */ + return (s->base + s->shadow[index]) << PAGE_SHIFT; +} + +static void prepare_next_shadow(const struct cfi_shadow __rcu *prev, + struct cfi_shadow *next) +{ + int i, index, check; + + /* Mark everything invalid */ + memset(next->shadow, 0xFF, SHADOW_ARR_SIZE); + + if (!prev) + return; /* No previous shadow */ + + /* If the base address didn't change, an update is not needed */ + if (prev->base == next->base) { + memcpy(next->shadow, prev->shadow, SHADOW_ARR_SIZE); + return; + } + + /* Convert the previous shadow to the new address range */ + for (i = 0; i < SHADOW_ARR_SLOTS; ++i) { + if (prev->shadow[i] == SHADOW_INVALID) + continue; + + index = ptr_to_shadow(next, shadow_to_ptr(prev, i)); + if (index < 0) + continue; + + check = ptr_to_shadow(next, + shadow_to_check_fn(prev, prev->shadow[i])); + if (check < 0) + continue; + + next->shadow[index] = (shadow_t)check; + } +} + +static void add_module_to_shadow(struct cfi_shadow *s, struct module *mod, + unsigned long min_addr, unsigned long max_addr) +{ + int check_index; + unsigned long check = (unsigned long)mod->cfi_check; + unsigned long ptr; + + if (unlikely(!PAGE_ALIGNED(check))) { + pr_warn("cfi: not using shadow for module %s\n", mod->name); + return; + } + + check_index = ptr_to_shadow(s, check); + if (check_index < 0) + return; /* Module not addressable with shadow */ + + /* For each page, store the check function index in the shadow */ + for (ptr = min_addr; ptr <= max_addr; ptr += PAGE_SIZE) { + int index = ptr_to_shadow(s, ptr); + + if (index >= 0) { + /* Each page must only contain one module */ + WARN_ON_ONCE(s->shadow[index] != SHADOW_INVALID); + s->shadow[index] = (shadow_t)check_index; + } + } +} + +static void remove_module_from_shadow(struct cfi_shadow *s, struct module *mod, + unsigned long min_addr, unsigned long max_addr) +{ + unsigned long ptr; + + for (ptr = min_addr; ptr <= max_addr; ptr += PAGE_SIZE) { + int index = ptr_to_shadow(s, ptr); + + if (index >= 0) + s->shadow[index] = SHADOW_INVALID; + } +} + +typedef void (*update_shadow_fn)(struct cfi_shadow *, struct module *, + unsigned long min_addr, unsigned long max_addr); + +static void update_shadow(struct module *mod, unsigned long base_addr, + update_shadow_fn fn) +{ + struct cfi_shadow *prev; + struct cfi_shadow *next; + unsigned long min_addr, max_addr; + + next = vmalloc(SHADOW_SIZE); + + mutex_lock(&shadow_update_lock); + prev = rcu_dereference_protected(cfi_shadow, + mutex_is_locked(&shadow_update_lock)); + + if (next) { + next->base = base_addr >> PAGE_SHIFT; + prepare_next_shadow(prev, next); + + min_addr = (unsigned long)mod->core_layout.base; + max_addr = min_addr + mod->core_layout.text_size; + fn(next, mod, min_addr & PAGE_MASK, max_addr & PAGE_MASK); + + set_memory_ro((unsigned long)next, SHADOW_PAGES); + } + + rcu_assign_pointer(cfi_shadow, next); + mutex_unlock(&shadow_update_lock); + synchronize_rcu(); + + if (prev) { + set_memory_rw((unsigned long)prev, SHADOW_PAGES); + vfree(prev); + } +} + +void cfi_module_add(struct module *mod, unsigned long base_addr) +{ + update_shadow(mod, base_addr, add_module_to_shadow); +} + +void cfi_module_remove(struct module *mod, unsigned long base_addr) +{ + update_shadow(mod, base_addr, remove_module_from_shadow); +} + +static inline cfi_check_fn ptr_to_check_fn(const struct cfi_shadow __rcu *s, + unsigned long ptr) +{ + int index; + + if (unlikely(!s)) + return NULL; /* No shadow available */ + + index = ptr_to_shadow(s, ptr); + if (index < 0) + return NULL; /* Cannot be addressed with shadow */ + + return (cfi_check_fn)shadow_to_check_fn(s, index); +} + +static inline cfi_check_fn find_shadow_check_fn(unsigned long ptr) +{ + cfi_check_fn fn; + + rcu_read_lock_sched(); + fn = ptr_to_check_fn(rcu_dereference_sched(cfi_shadow), ptr); + rcu_read_unlock_sched(); + + return fn; +} + +#else /* !CONFIG_CFI_CLANG_SHADOW */ + +static inline cfi_check_fn find_shadow_check_fn(unsigned long ptr) +{ + return NULL; +} + +#endif /* CONFIG_CFI_CLANG_SHADOW */ + +static inline cfi_check_fn find_module_check_fn(unsigned long ptr) +{ + cfi_check_fn fn = NULL; + struct module *mod; + + rcu_read_lock_sched(); + mod = __module_address(ptr); + if (mod) + fn = mod->cfi_check; + rcu_read_unlock_sched(); + + return fn; +} + +static inline cfi_check_fn find_check_fn(unsigned long ptr) +{ + cfi_check_fn fn = NULL; + + if (is_kernel_text(ptr)) + return __cfi_check; + + /* + * Indirect call checks can happen when RCU is not watching. Both + * the shadow and __module_address use RCU, so we need to wake it + * up if necessary. + */ + RCU_NONIDLE({ + if (IS_ENABLED(CONFIG_CFI_CLANG_SHADOW)) + fn = find_shadow_check_fn(ptr); + + if (!fn) + fn = find_module_check_fn(ptr); + }); + + return fn; +} + +void __cfi_slowpath_diag(uint64_t id, void *ptr, void *diag) +{ + cfi_check_fn fn = find_check_fn((unsigned long)ptr); + + if (likely(fn)) + fn(id, ptr, diag); + else /* Don't allow unchecked modules */ + handle_cfi_failure(ptr); +} +EXPORT_SYMBOL(__cfi_slowpath_diag); + +#else /* !CONFIG_MODULES */ + +void __cfi_slowpath_diag(uint64_t id, void *ptr, void *diag) +{ + handle_cfi_failure(ptr); /* No modules */ +} +EXPORT_SYMBOL(__cfi_slowpath_diag); + +#endif /* CONFIG_MODULES */ + +void cfi_failure_handler(void *data, void *ptr, void *vtable) +{ + handle_cfi_failure(ptr); +} +EXPORT_SYMBOL(cfi_failure_handler); diff --git a/kernel/kallsyms.c b/kernel/kallsyms.c index 8043a90aa50e..c851ca0ed357 100644 --- a/kernel/kallsyms.c +++ b/kernel/kallsyms.c @@ -161,6 +161,27 @@ static unsigned long kallsyms_sym_address(int idx) return kallsyms_relative_base - 1 - kallsyms_offsets[idx]; } +#if defined(CONFIG_CFI_CLANG) && defined(CONFIG_LTO_CLANG_THIN) +/* + * LLVM appends a hash to static function names when ThinLTO and CFI are + * both enabled, i.e. foo() becomes foo$707af9a22804d33c81801f27dcfe489b. + * This causes confusion and potentially breaks user space tools, so we + * strip the suffix from expanded symbol names. + */ +static inline bool cleanup_symbol_name(char *s) +{ + char *res; + + res = strrchr(s, '$'); + if (res) + *res = '\0'; + + return res != NULL; +} +#else +static inline bool cleanup_symbol_name(char *s) { return false; } +#endif + /* Lookup the address for this symbol. Returns 0 if not found. */ unsigned long kallsyms_lookup_name(const char *name) { @@ -173,6 +194,9 @@ unsigned long kallsyms_lookup_name(const char *name) if (strcmp(namebuf, name) == 0) return kallsyms_sym_address(i); + + if (cleanup_symbol_name(namebuf) && strcmp(namebuf, name) == 0) + return kallsyms_sym_address(i); } return module_kallsyms_lookup_name(name); } @@ -303,7 +327,9 @@ const char *kallsyms_lookup(unsigned long addr, namebuf, KSYM_NAME_LEN); if (modname) *modname = NULL; - return namebuf; + + ret = namebuf; + goto found; } /* See if it's in a module or a BPF JITed image. */ @@ -316,11 +342,16 @@ const char *kallsyms_lookup(unsigned long addr, if (!ret) ret = ftrace_mod_address_lookup(addr, symbolsize, offset, modname, namebuf); + +found: + cleanup_symbol_name(namebuf); return ret; } int lookup_symbol_name(unsigned long addr, char *symname) { + int res; + symname[0] = '\0'; symname[KSYM_NAME_LEN - 1] = '\0'; @@ -331,15 +362,23 @@ int lookup_symbol_name(unsigned long addr, char *symname) /* Grab name */ kallsyms_expand_symbol(get_symbol_offset(pos), symname, KSYM_NAME_LEN); - return 0; + goto found; } /* See if it's in a module. */ - return lookup_module_symbol_name(addr, symname); + res = lookup_module_symbol_name(addr, symname); + if (res) + return res; + +found: + cleanup_symbol_name(symname); + return 0; } int lookup_symbol_attrs(unsigned long addr, unsigned long *size, unsigned long *offset, char *modname, char *name) { + int res; + name[0] = '\0'; name[KSYM_NAME_LEN - 1] = '\0'; @@ -351,10 +390,16 @@ int lookup_symbol_attrs(unsigned long addr, unsigned long *size, kallsyms_expand_symbol(get_symbol_offset(pos), name, KSYM_NAME_LEN); modname[0] = '\0'; - return 0; + goto found; } /* See if it's in a module. */ - return lookup_module_symbol_attrs(addr, size, offset, modname, name); + res = lookup_module_symbol_attrs(addr, size, offset, modname, name); + if (res) + return res; + +found: + cleanup_symbol_name(name); + return 0; } /* Look up a kernel symbol and return it in a text buffer. */ diff --git a/kernel/kthread.c b/kernel/kthread.c index 1578973c5740..a1972eba2917 100644 --- a/kernel/kthread.c +++ b/kernel/kthread.c @@ -963,7 +963,8 @@ static void __kthread_queue_delayed_work(struct kthread_worker *worker, struct timer_list *timer = &dwork->timer; struct kthread_work *work = &dwork->work; - WARN_ON_ONCE(timer->function != kthread_delayed_work_timer_fn); + WARN_ON_FUNCTION_MISMATCH(timer->function, + kthread_delayed_work_timer_fn); /* * If @delay is 0, queue @dwork->work immediately. This is for diff --git a/kernel/module.c b/kernel/module.c index 30479355ab85..20fb004e7d8d 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -2146,6 +2146,8 @@ void __weak module_arch_freeing_init(struct module *mod) { } +static void cfi_cleanup(struct module *mod); + /* Free a module, remove from lists, etc. */ static void free_module(struct module *mod) { @@ -2187,6 +2189,9 @@ static void free_module(struct module *mod) synchronize_rcu(); mutex_unlock(&module_mutex); + /* Clean up CFI for the module. */ + cfi_cleanup(mod); + /* This may be empty, but that's OK */ module_arch_freeing_init(mod); module_memfree(mod->init_layout.base); @@ -3866,6 +3871,8 @@ static int unknown_module_param_cb(char *param, char *val, const char *modname, return 0; } +static void cfi_init(struct module *mod); + /* * Allocate and load the module: note that size of section 0 is always * zero, and we rely on this for optional sections. @@ -3997,6 +4004,9 @@ static int load_module(struct load_info *info, const char __user *uargs, flush_module_icache(mod); + /* Setup CFI for the module. */ + cfi_init(mod); + /* Now copy in args */ mod->args = strndup_user(uargs, ~0UL >> 1); if (IS_ERR(mod->args)) { @@ -4070,6 +4080,7 @@ static int load_module(struct load_info *info, const char __user *uargs, synchronize_rcu(); kfree(mod->args); free_arch_cleanup: + cfi_cleanup(mod); module_arch_cleanup(mod); free_modinfo: free_modinfo(mod); @@ -4415,6 +4426,38 @@ int module_kallsyms_on_each_symbol(int (*fn)(void *, const char *, #endif /* CONFIG_LIVEPATCH */ #endif /* CONFIG_KALLSYMS */ +static void cfi_init(struct module *mod) +{ +#ifdef CONFIG_CFI_CLANG + initcall_t *init; + exitcall_t *exit; + + rcu_read_lock_sched(); + mod->cfi_check = (cfi_check_fn) + find_kallsyms_symbol_value(mod, "__cfi_check"); + init = (initcall_t *) + find_kallsyms_symbol_value(mod, "__cfi_jt_init_module"); + exit = (exitcall_t *) + find_kallsyms_symbol_value(mod, "__cfi_jt_cleanup_module"); + rcu_read_unlock_sched(); + + /* Fix init/exit functions to point to the CFI jump table */ + if (init) + mod->init = *init; + if (exit) + mod->exit = *exit; + + cfi_module_add(mod, module_addr_min); +#endif +} + +static void cfi_cleanup(struct module *mod) +{ +#ifdef CONFIG_CFI_CLANG + cfi_module_remove(mod, module_addr_min); +#endif +} + /* Maximum number of characters written by module_flags() */ #define MODULE_FLAGS_BUF_SIZE (TAINT_FLAGS_COUNT + 4) diff --git a/kernel/workqueue.c b/kernel/workqueue.c index 79f2319543ce..b19d759e55a5 100644 --- a/kernel/workqueue.c +++ b/kernel/workqueue.c @@ -1630,7 +1630,7 @@ static void __queue_delayed_work(int cpu, struct workqueue_struct *wq, struct work_struct *work = &dwork->work; WARN_ON_ONCE(!wq); - WARN_ON_ONCE(timer->function != delayed_work_timer_fn); + WARN_ON_FUNCTION_MISMATCH(timer->function, delayed_work_timer_fn); WARN_ON_ONCE(timer_pending(timer)); WARN_ON_ONCE(!list_empty(&work->entry)); diff --git a/lib/list_sort.c b/lib/list_sort.c index 52f0c258c895..a926d96ffd44 100644 --- a/lib/list_sort.c +++ b/lib/list_sort.c @@ -7,16 +7,13 @@ #include <linux/list_sort.h> #include <linux/list.h> -typedef int __attribute__((nonnull(2,3))) (*cmp_func)(void *, - struct list_head const *, struct list_head const *); - /* * Returns a list organized in an intermediate format suited * to chaining of merge() calls: null-terminated, no reserved or * sentinel head node, "prev" links not maintained. */ __attribute__((nonnull(2,3,4))) -static struct list_head *merge(void *priv, cmp_func cmp, +static struct list_head *merge(void *priv, list_cmp_func_t cmp, struct list_head *a, struct list_head *b) { struct list_head *head, **tail = &head; @@ -52,7 +49,7 @@ static struct list_head *merge(void *priv, cmp_func cmp, * throughout. */ __attribute__((nonnull(2,3,4,5))) -static void merge_final(void *priv, cmp_func cmp, struct list_head *head, +static void merge_final(void *priv, list_cmp_func_t cmp, struct list_head *head, struct list_head *a, struct list_head *b) { struct list_head *tail = head; @@ -185,9 +182,7 @@ static void merge_final(void *priv, cmp_func cmp, struct list_head *head, * 2^(k+1) - 1 (second merge of case 5 when x == 2^(k-1) - 1). */ __attribute__((nonnull(2,3))) -void list_sort(void *priv, struct list_head *head, - int (*cmp)(void *priv, struct list_head *a, - struct list_head *b)) +void list_sort(void *priv, struct list_head *head, list_cmp_func_t cmp) { struct list_head *list = head->next, *pending = NULL; size_t count = 0; /* Count of pending */ @@ -227,7 +222,7 @@ void list_sort(void *priv, struct list_head *head, if (likely(bits)) { struct list_head *a = *tail, *b = a->prev; - a = merge(priv, (cmp_func)cmp, b, a); + a = merge(priv, cmp, b, a); /* Install the merged result in place of the inputs */ a->prev = b->prev; *tail = a; @@ -249,10 +244,10 @@ void list_sort(void *priv, struct list_head *head, if (!next) break; - list = merge(priv, (cmp_func)cmp, pending, list); + list = merge(priv, cmp, pending, list); pending = next; } /* The final merge, rebuilding prev links */ - merge_final(priv, (cmp_func)cmp, head, pending, list); + merge_final(priv, cmp, head, pending, list); } EXPORT_SYMBOL(list_sort); diff --git a/lib/test_list_sort.c b/lib/test_list_sort.c index 1f017d3b610e..00daaf23316f 100644 --- a/lib/test_list_sort.c +++ b/lib/test_list_sort.c @@ -56,7 +56,8 @@ static int __init check(struct debug_el *ela, struct debug_el *elb) return 0; } -static int __init cmp(void *priv, struct list_head *a, struct list_head *b) +static int __init cmp(void *priv, const struct list_head *a, + const struct list_head *b) { struct debug_el *ela, *elb; diff --git a/net/tipc/name_table.c b/net/tipc/name_table.c index ee5ac40ea2b6..f8141443f2e2 100644 --- a/net/tipc/name_table.c +++ b/net/tipc/name_table.c @@ -397,8 +397,8 @@ static struct publication *tipc_service_remove_publ(struct service_range *sr, * Code reused: time_after32() for the same purpose */ #define publication_after(pa, pb) time_after32((pa)->id, (pb)->id) -static int tipc_publ_sort(void *priv, struct list_head *a, - struct list_head *b) +static int tipc_publ_sort(void *priv, const struct list_head *a, + const struct list_head *b) { struct publication *pa, *pb; diff --git a/scripts/Makefile.modfinal b/scripts/Makefile.modfinal index 735e11e9041b..dd87cea9fba7 100644 --- a/scripts/Makefile.modfinal +++ b/scripts/Makefile.modfinal @@ -23,7 +23,7 @@ modname = $(notdir $(@:.mod.o=)) part-of-module = y quiet_cmd_cc_o_c = CC [M] $@ - cmd_cc_o_c = $(CC) $(c_flags) -c -o $@ $< + cmd_cc_o_c = $(CC) $(filter-out $(CC_FLAGS_CFI), $(c_flags)) -c -o $@ $< %.mod.o: %.mod.c FORCE $(call if_changed_dep,cc_o_c) diff --git a/scripts/module.lds.S b/scripts/module.lds.S index 2c52535f9b56..04c5685c25cf 100644 --- a/scripts/module.lds.S +++ b/scripts/module.lds.S @@ -3,10 +3,20 @@ * Archs are free to supply their own linker scripts. ld will * combine them automatically. */ +#ifdef CONFIG_CFI_CLANG +# include <asm/page.h> +# define ALIGN_CFI ALIGN(PAGE_SIZE) +# define SANITIZER_DISCARDS *(.eh_frame) +#else +# define ALIGN_CFI +# define SANITIZER_DISCARDS +#endif + SECTIONS { /DISCARD/ : { *(.discard) *(.discard.*) + SANITIZER_DISCARDS } __ksymtab 0 : { *(SORT(___ksymtab+*)) } @@ -41,7 +51,14 @@ SECTIONS { *(.rodata..L*) } - .text : { *(.text .text.[0-9a-zA-Z_]*) } + /* + * With CONFIG_CFI_CLANG, we assume __cfi_check is at the beginning + * of the .text section, and is aligned to PAGE_SIZE. + */ + .text : ALIGN_CFI { + *(.text.__cfi_check) + *(.text .text.[0-9a-zA-Z_]* .text..L.cfi*) + } #endif } |