diff options
Diffstat (limited to 'arch/x86')
| -rw-r--r-- | arch/x86/entry/entry_64.S | 18 | ||||
| -rw-r--r-- | arch/x86/events/intel/core.c | 10 | ||||
| -rw-r--r-- | arch/x86/include/asm/mmu_context.h | 6 | ||||
| -rw-r--r-- | arch/x86/include/asm/mpx.h | 15 | ||||
| -rw-r--r-- | arch/x86/include/asm/pgtable_64.h | 3 | ||||
| -rw-r--r-- | arch/x86/include/asm/text-patching.h | 28 | ||||
| -rw-r--r-- | arch/x86/kernel/ftrace.c | 32 | ||||
| -rw-r--r-- | arch/x86/kvm/hyperv.c | 11 | ||||
| -rw-r--r-- | arch/x86/lib/Makefile | 12 | ||||
| -rw-r--r-- | arch/x86/mm/mpx.c | 10 |
10 files changed, 118 insertions, 27 deletions
diff --git a/arch/x86/entry/entry_64.S b/arch/x86/entry/entry_64.S index 89494965e9f9..4150bd0f5adf 100644 --- a/arch/x86/entry/entry_64.S +++ b/arch/x86/entry/entry_64.S @@ -881,7 +881,7 @@ apicinterrupt IRQ_WORK_VECTOR irq_work_interrupt smp_irq_work_interrupt * @paranoid == 2 is special: the stub will never switch stacks. This is for * #DF: if the thread stack is somehow unusable, we'll still get a useful OOPS. */ -.macro idtentry sym do_sym has_error_code:req paranoid=0 shift_ist=-1 +.macro idtentry sym do_sym has_error_code:req paranoid=0 shift_ist=-1 create_gap=0 ENTRY(\sym) UNWIND_HINT_IRET_REGS offset=\has_error_code*8 @@ -901,6 +901,20 @@ ENTRY(\sym) jnz .Lfrom_usermode_switch_stack_\@ .endif + .if \create_gap == 1 + /* + * If coming from kernel space, create a 6-word gap to allow the + * int3 handler to emulate a call instruction. + */ + testb $3, CS-ORIG_RAX(%rsp) + jnz .Lfrom_usermode_no_gap_\@ + .rept 6 + pushq 5*8(%rsp) + .endr + UNWIND_HINT_IRET_REGS offset=8 +.Lfrom_usermode_no_gap_\@: + .endif + .if \paranoid call paranoid_entry .else @@ -1132,7 +1146,7 @@ apicinterrupt3 HYPERV_STIMER0_VECTOR \ #endif /* CONFIG_HYPERV */ idtentry debug do_debug has_error_code=0 paranoid=1 shift_ist=DEBUG_STACK -idtentry int3 do_int3 has_error_code=0 +idtentry int3 do_int3 has_error_code=0 create_gap=1 idtentry stack_segment do_stack_segment has_error_code=1 #ifdef CONFIG_XEN_PV diff --git a/arch/x86/events/intel/core.c b/arch/x86/events/intel/core.c index 71fb8b7b2954..c87b06ad9f86 100644 --- a/arch/x86/events/intel/core.c +++ b/arch/x86/events/intel/core.c @@ -2090,15 +2090,19 @@ static void intel_pmu_disable_event(struct perf_event *event) cpuc->intel_ctrl_host_mask &= ~(1ull << hwc->idx); cpuc->intel_cp_status &= ~(1ull << hwc->idx); - if (unlikely(event->attr.precise_ip)) - intel_pmu_pebs_disable(event); - if (unlikely(hwc->config_base == MSR_ARCH_PERFMON_FIXED_CTR_CTRL)) { intel_pmu_disable_fixed(hwc); return; } x86_pmu_disable_event(event); + + /* + * Needs to be called after x86_pmu_disable_event, + * so we don't trigger the event without PEBS bit set. + */ + if (unlikely(event->attr.precise_ip)) + intel_pmu_pebs_disable(event); } static void intel_pmu_del_event(struct perf_event *event) diff --git a/arch/x86/include/asm/mmu_context.h b/arch/x86/include/asm/mmu_context.h index 19d18fae6ec6..41019af68adf 100644 --- a/arch/x86/include/asm/mmu_context.h +++ b/arch/x86/include/asm/mmu_context.h @@ -277,8 +277,8 @@ static inline void arch_bprm_mm_init(struct mm_struct *mm, mpx_mm_init(mm); } -static inline void arch_unmap(struct mm_struct *mm, struct vm_area_struct *vma, - unsigned long start, unsigned long end) +static inline void arch_unmap(struct mm_struct *mm, unsigned long start, + unsigned long end) { /* * mpx_notify_unmap() goes and reads a rarely-hot @@ -298,7 +298,7 @@ static inline void arch_unmap(struct mm_struct *mm, struct vm_area_struct *vma, * consistently wrong. */ if (unlikely(cpu_feature_enabled(X86_FEATURE_MPX))) - mpx_notify_unmap(mm, vma, start, end); + mpx_notify_unmap(mm, start, end); } /* diff --git a/arch/x86/include/asm/mpx.h b/arch/x86/include/asm/mpx.h index d0b1434fb0b6..143a5c193ed3 100644 --- a/arch/x86/include/asm/mpx.h +++ b/arch/x86/include/asm/mpx.h @@ -64,12 +64,15 @@ struct mpx_fault_info { }; #ifdef CONFIG_X86_INTEL_MPX -int mpx_fault_info(struct mpx_fault_info *info, struct pt_regs *regs); -int mpx_handle_bd_fault(void); + +extern int mpx_fault_info(struct mpx_fault_info *info, struct pt_regs *regs); +extern int mpx_handle_bd_fault(void); + static inline int kernel_managing_mpx_tables(struct mm_struct *mm) { return (mm->context.bd_addr != MPX_INVALID_BOUNDS_DIR); } + static inline void mpx_mm_init(struct mm_struct *mm) { /* @@ -78,11 +81,10 @@ static inline void mpx_mm_init(struct mm_struct *mm) */ mm->context.bd_addr = MPX_INVALID_BOUNDS_DIR; } -void mpx_notify_unmap(struct mm_struct *mm, struct vm_area_struct *vma, - unsigned long start, unsigned long end); -unsigned long mpx_unmapped_area_check(unsigned long addr, unsigned long len, - unsigned long flags); +extern void mpx_notify_unmap(struct mm_struct *mm, unsigned long start, unsigned long end); +extern unsigned long mpx_unmapped_area_check(unsigned long addr, unsigned long len, unsigned long flags); + #else static inline int mpx_fault_info(struct mpx_fault_info *info, struct pt_regs *regs) { @@ -100,7 +102,6 @@ static inline void mpx_mm_init(struct mm_struct *mm) { } static inline void mpx_notify_unmap(struct mm_struct *mm, - struct vm_area_struct *vma, unsigned long start, unsigned long end) { } diff --git a/arch/x86/include/asm/pgtable_64.h b/arch/x86/include/asm/pgtable_64.h index 9c85b54bf03c..0bb566315621 100644 --- a/arch/x86/include/asm/pgtable_64.h +++ b/arch/x86/include/asm/pgtable_64.h @@ -259,8 +259,7 @@ extern void init_extra_mapping_uc(unsigned long phys, unsigned long size); extern void init_extra_mapping_wb(unsigned long phys, unsigned long size); #define gup_fast_permitted gup_fast_permitted -static inline bool gup_fast_permitted(unsigned long start, int nr_pages, - int write) +static inline bool gup_fast_permitted(unsigned long start, int nr_pages) { unsigned long len, end; diff --git a/arch/x86/include/asm/text-patching.h b/arch/x86/include/asm/text-patching.h index e85ff65c43c3..05861cc08787 100644 --- a/arch/x86/include/asm/text-patching.h +++ b/arch/x86/include/asm/text-patching.h @@ -39,4 +39,32 @@ extern int poke_int3_handler(struct pt_regs *regs); extern void *text_poke_bp(void *addr, const void *opcode, size_t len, void *handler); extern int after_bootmem; +static inline void int3_emulate_jmp(struct pt_regs *regs, unsigned long ip) +{ + regs->ip = ip; +} + +#define INT3_INSN_SIZE 1 +#define CALL_INSN_SIZE 5 + +#ifdef CONFIG_X86_64 +static inline void int3_emulate_push(struct pt_regs *regs, unsigned long val) +{ + /* + * The int3 handler in entry_64.S adds a gap between the + * stack where the break point happened, and the saving of + * pt_regs. We can extend the original stack because of + * this gap. See the idtentry macro's create_gap option. + */ + regs->sp -= sizeof(unsigned long); + *(unsigned long *)regs->sp = val; +} + +static inline void int3_emulate_call(struct pt_regs *regs, unsigned long func) +{ + int3_emulate_push(regs, regs->ip - INT3_INSN_SIZE + CALL_INSN_SIZE); + int3_emulate_jmp(regs, func); +} +#endif + #endif /* _ASM_X86_TEXT_PATCHING_H */ diff --git a/arch/x86/kernel/ftrace.c b/arch/x86/kernel/ftrace.c index 763d4264d16a..2ee4b12a70e8 100644 --- a/arch/x86/kernel/ftrace.c +++ b/arch/x86/kernel/ftrace.c @@ -29,6 +29,7 @@ #include <asm/kprobes.h> #include <asm/ftrace.h> #include <asm/nops.h> +#include <asm/text-patching.h> #ifdef CONFIG_DYNAMIC_FTRACE @@ -231,6 +232,7 @@ int ftrace_modify_call(struct dyn_ftrace *rec, unsigned long old_addr, } static unsigned long ftrace_update_func; +static unsigned long ftrace_update_func_call; static int update_ftrace_func(unsigned long ip, void *new) { @@ -259,6 +261,8 @@ int ftrace_update_ftrace_func(ftrace_func_t func) unsigned char *new; int ret; + ftrace_update_func_call = (unsigned long)func; + new = ftrace_call_replace(ip, (unsigned long)func); ret = update_ftrace_func(ip, new); @@ -294,13 +298,28 @@ int ftrace_int3_handler(struct pt_regs *regs) if (WARN_ON_ONCE(!regs)) return 0; - ip = regs->ip - 1; - if (!ftrace_location(ip) && !is_ftrace_caller(ip)) - return 0; + ip = regs->ip - INT3_INSN_SIZE; - regs->ip += MCOUNT_INSN_SIZE - 1; +#ifdef CONFIG_X86_64 + if (ftrace_location(ip)) { + int3_emulate_call(regs, (unsigned long)ftrace_regs_caller); + return 1; + } else if (is_ftrace_caller(ip)) { + if (!ftrace_update_func_call) { + int3_emulate_jmp(regs, ip + CALL_INSN_SIZE); + return 1; + } + int3_emulate_call(regs, ftrace_update_func_call); + return 1; + } +#else + if (ftrace_location(ip) || is_ftrace_caller(ip)) { + int3_emulate_jmp(regs, ip + CALL_INSN_SIZE); + return 1; + } +#endif - return 1; + return 0; } static int ftrace_write(unsigned long ip, const char *val, int size) @@ -858,6 +877,8 @@ void arch_ftrace_update_trampoline(struct ftrace_ops *ops) func = ftrace_ops_get_func(ops); + ftrace_update_func_call = (unsigned long)func; + /* Do a safe modify in case the trampoline is executing */ new = ftrace_call_replace(ip, (unsigned long)func); ret = update_ftrace_func(ip, new); @@ -959,6 +980,7 @@ static int ftrace_mod_jmp(unsigned long ip, void *func) { unsigned char *new; + ftrace_update_func_call = 0UL; new = ftrace_jmp_replace(ip, (unsigned long)func); return update_ftrace_func(ip, new); diff --git a/arch/x86/kvm/hyperv.c b/arch/x86/kvm/hyperv.c index 371c669696d7..610c0f1fbdd7 100644 --- a/arch/x86/kvm/hyperv.c +++ b/arch/x86/kvm/hyperv.c @@ -1371,7 +1371,16 @@ static u64 kvm_hv_flush_tlb(struct kvm_vcpu *current_vcpu, u64 ingpa, valid_bank_mask = BIT_ULL(0); sparse_banks[0] = flush.processor_mask; - all_cpus = flush.flags & HV_FLUSH_ALL_PROCESSORS; + + /* + * Work around possible WS2012 bug: it sends hypercalls + * with processor_mask = 0x0 and HV_FLUSH_ALL_PROCESSORS clear, + * while also expecting us to flush something and crashing if + * we don't. Let's treat processor_mask == 0 same as + * HV_FLUSH_ALL_PROCESSORS. + */ + all_cpus = (flush.flags & HV_FLUSH_ALL_PROCESSORS) || + flush.processor_mask == 0; } else { if (unlikely(kvm_read_guest(kvm, ingpa, &flush_ex, sizeof(flush_ex)))) diff --git a/arch/x86/lib/Makefile b/arch/x86/lib/Makefile index 140e61843a07..3cb3af51ec89 100644 --- a/arch/x86/lib/Makefile +++ b/arch/x86/lib/Makefile @@ -6,6 +6,18 @@ # Produces uninteresting flaky coverage. KCOV_INSTRUMENT_delay.o := n +# Early boot use of cmdline; don't instrument it +ifdef CONFIG_AMD_MEM_ENCRYPT +KCOV_INSTRUMENT_cmdline.o := n +KASAN_SANITIZE_cmdline.o := n + +ifdef CONFIG_FUNCTION_TRACER +CFLAGS_REMOVE_cmdline.o = -pg +endif + +CFLAGS_cmdline.o := $(call cc-option, -fno-stack-protector) +endif + inat_tables_script = $(srctree)/arch/x86/tools/gen-insn-attr-x86.awk inat_tables_maps = $(srctree)/arch/x86/lib/x86-opcode-map.txt quiet_cmd_inat_tables = GEN $@ diff --git a/arch/x86/mm/mpx.c b/arch/x86/mm/mpx.c index de1851d15699..ea17ff6c8588 100644 --- a/arch/x86/mm/mpx.c +++ b/arch/x86/mm/mpx.c @@ -881,9 +881,10 @@ static int mpx_unmap_tables(struct mm_struct *mm, * the virtual address region start...end have already been split if * necessary, and the 'vma' is the first vma in this range (start -> end). */ -void mpx_notify_unmap(struct mm_struct *mm, struct vm_area_struct *vma, - unsigned long start, unsigned long end) +void mpx_notify_unmap(struct mm_struct *mm, unsigned long start, + unsigned long end) { + struct vm_area_struct *vma; int ret; /* @@ -902,11 +903,12 @@ void mpx_notify_unmap(struct mm_struct *mm, struct vm_area_struct *vma, * which should not occur normally. Being strict about it here * helps ensure that we do not have an exploitable stack overflow. */ - do { + vma = find_vma(mm, start); + while (vma && vma->vm_start < end) { if (vma->vm_flags & VM_MPX) return; vma = vma->vm_next; - } while (vma && vma->vm_start < end); + } ret = mpx_unmap_tables(mm, start, end); if (ret) |