diff options
Diffstat (limited to 'arch')
24 files changed, 1297 insertions, 43 deletions
diff --git a/arch/ia64/include/uapi/asm/siginfo.h b/arch/ia64/include/uapi/asm/siginfo.h index 4ea6225196bb..bce9bc1a66c4 100644 --- a/arch/ia64/include/uapi/asm/siginfo.h +++ b/arch/ia64/include/uapi/asm/siginfo.h @@ -63,6 +63,10 @@ typedef struct siginfo { unsigned int _flags; /* see below */ unsigned long _isr; /* isr */ short _addr_lsb; /* lsb of faulting address */ + struct { + void __user *_lower; + void __user *_upper; + } _addr_bnd; } _sigfault; /* SIGPOLL */ @@ -110,9 +114,9 @@ typedef struct siginfo { /* * SIGSEGV si_codes */ -#define __SEGV_PSTKOVF (__SI_FAULT|3) /* paragraph stack overflow */ +#define __SEGV_PSTKOVF (__SI_FAULT|4) /* paragraph stack overflow */ #undef NSIGSEGV -#define NSIGSEGV 3 +#define NSIGSEGV 4 #undef NSIGTRAP #define NSIGTRAP 4 diff --git a/arch/mips/include/uapi/asm/siginfo.h b/arch/mips/include/uapi/asm/siginfo.h index e81174432bab..d08f83f19db5 100644 --- a/arch/mips/include/uapi/asm/siginfo.h +++ b/arch/mips/include/uapi/asm/siginfo.h @@ -92,6 +92,10 @@ typedef struct siginfo { int _trapno; /* TRAP # which caused the signal */ #endif short _addr_lsb; + struct { + void __user *_lower; + void __user *_upper; + } _addr_bnd; } _sigfault; /* SIGPOLL, SIGXFSZ (To do ...) */ diff --git a/arch/s390/include/asm/mmu_context.h b/arch/s390/include/asm/mmu_context.h index 3815bfea1b2d..f49b71954654 100644 --- a/arch/s390/include/asm/mmu_context.h +++ b/arch/s390/include/asm/mmu_context.h @@ -120,4 +120,15 @@ static inline void arch_exit_mmap(struct mm_struct *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_bprm_mm_init(struct mm_struct *mm, + struct vm_area_struct *vma) +{ +} + #endif /* __S390_MMU_CONTEXT_H */ diff --git a/arch/um/include/asm/mmu_context.h b/arch/um/include/asm/mmu_context.h index aa4a743dc4ab..941527e507f7 100644 --- a/arch/um/include/asm/mmu_context.h +++ b/arch/um/include/asm/mmu_context.h @@ -10,7 +10,26 @@ #include <asm/mmu.h> extern void uml_setup_stubs(struct mm_struct *mm); +/* + * Needed since we do not use the asm-generic/mm_hooks.h: + */ +static inline void arch_dup_mmap(struct mm_struct *oldmm, struct mm_struct *mm) +{ + uml_setup_stubs(mm); +} extern void arch_exit_mmap(struct mm_struct *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_bprm_mm_init(struct mm_struct *mm, + struct vm_area_struct *vma) +{ +} +/* + * end asm-generic/mm_hooks.h functions + */ #define deactivate_mm(tsk,mm) do { } while (0) @@ -41,11 +60,6 @@ static inline void switch_mm(struct mm_struct *prev, struct mm_struct *next, } } -static inline void arch_dup_mmap(struct mm_struct *oldmm, struct mm_struct *mm) -{ - uml_setup_stubs(mm); -} - static inline void enter_lazy_tlb(struct mm_struct *mm, struct task_struct *tsk) { diff --git a/arch/unicore32/include/asm/mmu_context.h b/arch/unicore32/include/asm/mmu_context.h index ef470a7a3d0f..1cb5220afaf9 100644 --- a/arch/unicore32/include/asm/mmu_context.h +++ b/arch/unicore32/include/asm/mmu_context.h @@ -86,4 +86,15 @@ static inline void arch_dup_mmap(struct mm_struct *oldmm, { } +static inline void arch_unmap(struct mm_struct *mm, + struct vm_area_struct *vma, + unsigned long start, unsigned long end) +{ +} + +static inline void arch_bprm_mm_init(struct mm_struct *mm, + struct vm_area_struct *vma) +{ +} + #endif diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index 41a503c15862..666ac6651c17 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -248,6 +248,10 @@ config HAVE_INTEL_TXT def_bool y depends on INTEL_IOMMU && ACPI +config X86_INTEL_MPX + def_bool y + depends on CPU_SUP_INTEL + config X86_32_SMP def_bool y depends on X86_32 && SMP diff --git a/arch/x86/include/asm/disabled-features.h b/arch/x86/include/asm/disabled-features.h index 97534a7d38e3..f226df064660 100644 --- a/arch/x86/include/asm/disabled-features.h +++ b/arch/x86/include/asm/disabled-features.h @@ -10,6 +10,12 @@ * cpu_feature_enabled(). */ +#ifdef CONFIG_X86_INTEL_MPX +# define DISABLE_MPX 0 +#else +# define DISABLE_MPX (1<<(X86_FEATURE_MPX & 31)) +#endif + #ifdef CONFIG_X86_64 # define DISABLE_VME (1<<(X86_FEATURE_VME & 31)) # define DISABLE_K6_MTRR (1<<(X86_FEATURE_K6_MTRR & 31)) @@ -34,6 +40,6 @@ #define DISABLED_MASK6 0 #define DISABLED_MASK7 0 #define DISABLED_MASK8 0 -#define DISABLED_MASK9 0 +#define DISABLED_MASK9 (DISABLE_MPX) #endif /* _ASM_X86_DISABLED_FEATURES_H */ diff --git a/arch/x86/include/asm/insn.h b/arch/x86/include/asm/insn.h index 48eb30a86062..47f29b1d1846 100644 --- a/arch/x86/include/asm/insn.h +++ b/arch/x86/include/asm/insn.h @@ -65,6 +65,7 @@ struct insn { unsigned char x86_64; const insn_byte_t *kaddr; /* kernel address of insn to analyze */ + const insn_byte_t *end_kaddr; /* kernel address of last insn in buffer */ const insn_byte_t *next_byte; }; @@ -96,7 +97,7 @@ struct insn { #define X86_VEX_P(vex) ((vex) & 0x03) /* VEX3 Byte2, VEX2 Byte1 */ #define X86_VEX_M_MAX 0x1f /* VEX3.M Maximum value */ -extern void insn_init(struct insn *insn, const void *kaddr, int x86_64); +extern void insn_init(struct insn *insn, const void *kaddr, int buf_len, int x86_64); extern void insn_get_prefixes(struct insn *insn); extern void insn_get_opcode(struct insn *insn); extern void insn_get_modrm(struct insn *insn); @@ -115,12 +116,13 @@ static inline void insn_get_attribute(struct insn *insn) extern int insn_rip_relative(struct insn *insn); /* Init insn for kernel text */ -static inline void kernel_insn_init(struct insn *insn, const void *kaddr) +static inline void kernel_insn_init(struct insn *insn, + const void *kaddr, int buf_len) { #ifdef CONFIG_X86_64 - insn_init(insn, kaddr, 1); + insn_init(insn, kaddr, buf_len, 1); #else /* CONFIG_X86_32 */ - insn_init(insn, kaddr, 0); + insn_init(insn, kaddr, buf_len, 0); #endif } diff --git a/arch/x86/include/asm/mmu_context.h b/arch/x86/include/asm/mmu_context.h index 166af2a8e865..be91d5736e08 100644 --- a/arch/x86/include/asm/mmu_context.h +++ b/arch/x86/include/asm/mmu_context.h @@ -10,9 +10,8 @@ #include <asm/pgalloc.h> #include <asm/tlbflush.h> #include <asm/paravirt.h> +#include <asm/mpx.h> #ifndef CONFIG_PARAVIRT -#include <asm-generic/mm_hooks.h> - static inline void paravirt_activate_mm(struct mm_struct *prev, struct mm_struct *next) { @@ -102,4 +101,27 @@ do { \ } while (0) #endif +static inline void arch_dup_mmap(struct mm_struct *oldmm, + struct mm_struct *mm) +{ + paravirt_arch_dup_mmap(oldmm, mm); +} + +static inline void arch_exit_mmap(struct mm_struct *mm) +{ + paravirt_arch_exit_mmap(mm); +} + +static inline void arch_bprm_mm_init(struct mm_struct *mm, + struct vm_area_struct *vma) +{ + mpx_mm_init(mm); +} + +static inline void arch_unmap(struct mm_struct *mm, struct vm_area_struct *vma, + unsigned long start, unsigned long end) +{ + mpx_notify_unmap(mm, vma, start, end); +} + #endif /* _ASM_X86_MMU_CONTEXT_H */ diff --git a/arch/x86/include/asm/mpx.h b/arch/x86/include/asm/mpx.h new file mode 100644 index 000000000000..a952a13d59a7 --- /dev/null +++ b/arch/x86/include/asm/mpx.h @@ -0,0 +1,103 @@ +#ifndef _ASM_X86_MPX_H +#define _ASM_X86_MPX_H + +#include <linux/types.h> +#include <asm/ptrace.h> +#include <asm/insn.h> + +/* + * NULL is theoretically a valid place to put the bounds + * directory, so point this at an invalid address. + */ +#define MPX_INVALID_BOUNDS_DIR ((void __user *)-1) +#define MPX_BNDCFG_ENABLE_FLAG 0x1 +#define MPX_BD_ENTRY_VALID_FLAG 0x1 + +#ifdef CONFIG_X86_64 + +/* upper 28 bits [47:20] of the virtual address in 64-bit used to + * index into bounds directory (BD). + */ +#define MPX_BD_ENTRY_OFFSET 28 +#define MPX_BD_ENTRY_SHIFT 3 +/* bits [19:3] of the virtual address in 64-bit used to index into + * bounds table (BT). + */ +#define MPX_BT_ENTRY_OFFSET 17 +#define MPX_BT_ENTRY_SHIFT 5 +#define MPX_IGN_BITS 3 +#define MPX_BD_ENTRY_TAIL 3 + +#else + +#define MPX_BD_ENTRY_OFFSET 20 +#define MPX_BD_ENTRY_SHIFT 2 +#define MPX_BT_ENTRY_OFFSET 10 +#define MPX_BT_ENTRY_SHIFT 4 +#define MPX_IGN_BITS 2 +#define MPX_BD_ENTRY_TAIL 2 + +#endif + +#define MPX_BD_SIZE_BYTES (1UL<<(MPX_BD_ENTRY_OFFSET+MPX_BD_ENTRY_SHIFT)) +#define MPX_BT_SIZE_BYTES (1UL<<(MPX_BT_ENTRY_OFFSET+MPX_BT_ENTRY_SHIFT)) + +#define MPX_BNDSTA_TAIL 2 +#define MPX_BNDCFG_TAIL 12 +#define MPX_BNDSTA_ADDR_MASK (~((1UL<<MPX_BNDSTA_TAIL)-1)) +#define MPX_BNDCFG_ADDR_MASK (~((1UL<<MPX_BNDCFG_TAIL)-1)) +#define MPX_BT_ADDR_MASK (~((1UL<<MPX_BD_ENTRY_TAIL)-1)) + +#define MPX_BNDCFG_ADDR_MASK (~((1UL<<MPX_BNDCFG_TAIL)-1)) +#define MPX_BNDSTA_ERROR_CODE 0x3 + +#define MPX_BD_ENTRY_MASK ((1<<MPX_BD_ENTRY_OFFSET)-1) +#define MPX_BT_ENTRY_MASK ((1<<MPX_BT_ENTRY_OFFSET)-1) +#define MPX_GET_BD_ENTRY_OFFSET(addr) ((((addr)>>(MPX_BT_ENTRY_OFFSET+ \ + MPX_IGN_BITS)) & MPX_BD_ENTRY_MASK) << MPX_BD_ENTRY_SHIFT) +#define MPX_GET_BT_ENTRY_OFFSET(addr) ((((addr)>>MPX_IGN_BITS) & \ + MPX_BT_ENTRY_MASK) << MPX_BT_ENTRY_SHIFT) + +#ifdef CONFIG_X86_INTEL_MPX +siginfo_t *mpx_generate_siginfo(struct pt_regs *regs, + struct xsave_struct *xsave_buf); +int mpx_handle_bd_fault(struct xsave_struct *xsave_buf); +static inline int kernel_managing_mpx_tables(struct mm_struct *mm) +{ + return (mm->bd_addr != MPX_INVALID_BOUNDS_DIR); +} +static inline void mpx_mm_init(struct mm_struct *mm) +{ + /* + * NULL is theoretically a valid place to put the bounds + * directory, so point this at an invalid address. + */ + mm->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); +#else +static inline siginfo_t *mpx_generate_siginfo(struct pt_regs *regs, + struct xsave_struct *xsave_buf) +{ + return NULL; +} +static inline int mpx_handle_bd_fault(struct xsave_struct *xsave_buf) +{ + return -EINVAL; +} +static inline int kernel_managing_mpx_tables(struct mm_struct *mm) +{ + return 0; +} +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) +{ +} +#endif /* CONFIG_X86_INTEL_MPX */ + +#endif /* _ASM_X86_MPX_H */ diff --git a/arch/x86/include/asm/paravirt.h b/arch/x86/include/asm/paravirt.h index cd6e1610e29e..32444ae939ca 100644 --- a/arch/x86/include/asm/paravirt.h +++ b/arch/x86/include/asm/paravirt.h @@ -330,13 +330,13 @@ static inline void paravirt_activate_mm(struct mm_struct *prev, PVOP_VCALL2(pv_mmu_ops.activate_mm, prev, next); } -static inline void arch_dup_mmap(struct mm_struct *oldmm, - struct mm_struct *mm) +static inline void paravirt_arch_dup_mmap(struct mm_struct *oldmm, + struct mm_struct *mm) { PVOP_VCALL2(pv_mmu_ops.dup_mmap, oldmm, mm); } -static inline void arch_exit_mmap(struct mm_struct *mm) +static inline void paravirt_arch_exit_mmap(struct mm_struct *mm) { PVOP_VCALL1(pv_mmu_ops.exit_mmap, mm); } @@ -986,5 +986,15 @@ extern void default_banner(void); #endif /* __ASSEMBLY__ */ #else /* CONFIG_PARAVIRT */ # define default_banner x86_init_noop +#ifndef __ASSEMBLY__ +static inline void paravirt_arch_dup_mmap(struct mm_struct *oldmm, + struct mm_struct *mm) +{ +} + +static inline void paravirt_arch_exit_mmap(struct mm_struct *mm) +{ +} +#endif /* __ASSEMBLY__ */ #endif /* !CONFIG_PARAVIRT */ #endif /* _ASM_X86_PARAVIRT_H */ diff --git a/arch/x86/include/asm/processor.h b/arch/x86/include/asm/processor.h index eb71ec794732..9617a1716813 100644 --- a/arch/x86/include/asm/processor.h +++ b/arch/x86/include/asm/processor.h @@ -374,13 +374,14 @@ struct lwp_struct { u8 reserved[128]; }; -struct bndregs_struct { - u64 bndregs[8]; +struct bndreg { + u64 lower_bound; + u64 upper_bound; } __packed; -struct bndcsr_struct { - u64 cfg_reg_u; - u64 status_reg; +struct bndcsr { + u64 bndcfgu; + u64 bndstatus; } __packed; struct xsave_hdr_struct { @@ -394,8 +395,8 @@ struct xsave_struct { struct xsave_hdr_struct xsave_hdr; struct ymmh_struct ymmh; struct lwp_struct lwp; - struct bndregs_struct bndregs; - struct bndcsr_struct bndcsr; + struct bndreg bndreg[4]; + struct bndcsr bndcsr; /* new processor state extensions will go here */ } __attribute__ ((packed, aligned (64))); @@ -953,6 +954,24 @@ extern void start_thread(struct pt_regs *regs, unsigned long new_ip, extern int get_tsc_mode(unsigned long adr); extern int set_tsc_mode(unsigned int val); +/* Register/unregister a process' MPX related resource */ +#define MPX_ENABLE_MANAGEMENT(tsk) mpx_enable_management((tsk)) +#define MPX_DISABLE_MANAGEMENT(tsk) mpx_disable_management((tsk)) + +#ifdef CONFIG_X86_INTEL_MPX +extern int mpx_enable_management(struct task_struct *tsk); +extern int mpx_disable_management(struct task_struct *tsk); +#else +static inline int mpx_enable_management(struct task_struct *tsk) +{ + return -EINVAL; +} +static inline int mpx_disable_management(struct task_struct *tsk) +{ + return -EINVAL; +} +#endif /* CONFIG_X86_INTEL_MPX */ + extern u16 amd_get_nb_id(int cpu); static inline uint32_t hypervisor_cpuid_base(const char *sig, uint32_t leaves) diff --git a/arch/x86/kernel/cpu/perf_event_intel_ds.c b/arch/x86/kernel/cpu/perf_event_intel_ds.c index 495ae9793628..3c895d480cd7 100644 --- a/arch/x86/kernel/cpu/perf_event_intel_ds.c +++ b/arch/x86/kernel/cpu/perf_event_intel_ds.c @@ -724,6 +724,7 @@ static int intel_pmu_pebs_fixup_ip(struct pt_regs *regs) unsigned long ip = regs->ip; int is_64bit = 0; void *kaddr; + int size; /* * We don't need to fixup if the PEBS assist is fault like @@ -758,11 +759,12 @@ static int intel_pmu_pebs_fixup_ip(struct pt_regs *regs) return 1; } + size = ip - to; if (!kernel_ip(ip)) { - int size, bytes; + int bytes; u8 *buf = this_cpu_read(insn_buffer); - size = ip - to; /* Must fit our buffer, see above */ + /* 'size' must fit our buffer, see above */ bytes = copy_from_user_nmi(buf, (void __user *)to, size); if (bytes != 0) return 0; @@ -780,11 +782,20 @@ static int intel_pmu_pebs_fixup_ip(struct pt_regs *regs) #ifdef CONFIG_X86_64 is_64bit = kernel_ip(to) || !test_thread_flag(TIF_IA32); #endif - insn_init(&insn, kaddr, is_64bit); + insn_init(&insn, kaddr, size, is_64bit); insn_get_length(&insn); + /* + * Make sure there was not a problem decoding the + * instruction and getting the length. This is + * doubly important because we have an infinite + * loop if insn.length=0. + */ + if (!insn.length) + break; to += insn.length; kaddr += insn.length; + size -= insn.length; } while (to < ip); if (to == ip) { diff --git a/arch/x86/kernel/cpu/perf_event_intel_lbr.c b/arch/x86/kernel/cpu/perf_event_intel_lbr.c index 45fa730a5283..58f1a94beaf0 100644 --- a/arch/x86/kernel/cpu/perf_event_intel_lbr.c +++ b/arch/x86/kernel/cpu/perf_event_intel_lbr.c @@ -465,7 +465,7 @@ static int branch_type(unsigned long from, unsigned long to, int abort) { struct insn insn; void *addr; - int bytes, size = MAX_INSN_SIZE; + int bytes_read, bytes_left; int ret = X86_BR_NONE; int ext, to_plm, from_plm; u8 buf[MAX_INSN_SIZE]; @@ -493,8 +493,10 @@ static int branch_type(unsigned long from, unsigned long to, int abort) return X86_BR_NONE; /* may fail if text not present */ - bytes = copy_from_user_nmi(buf, (void __user *)from, size); - if (bytes != 0) + bytes_left = copy_from_user_nmi(buf, (void __user *)from, + MAX_INSN_SIZE); + bytes_read = MAX_INSN_SIZE - bytes_left; + if (!bytes_read) return X86_BR_NONE; addr = buf; @@ -505,10 +507,19 @@ static int branch_type(unsigned long from, unsigned long to, int abort) * Ensure we don't blindy read any address by validating it is * a known text address. */ - if (kernel_text_address(from)) + if (kernel_text_address(from)) { addr = (void *)from; - else + /* + * Assume we can get the maximum possible size + * when grabbing kernel data. This is not + * _strictly_ true since we could possibly be + * executing up next to a memory hole, but + * it is very unlikely to be a problem. + */ + bytes_read = MAX_INSN_SIZE; + } else { return X86_BR_NONE; + } } /* @@ -518,8 +529,10 @@ static int branch_type(unsigned long from, unsigned long to, int abort) #ifdef CONFIG_X86_64 is64 = kernel_ip((unsigned long)addr) || !test_thread_flag(TIF_IA32); #endif - insn_init(&insn, addr, is64); + insn_init(&insn, addr, bytes_read, is64); insn_get_opcode(&insn); + if (!insn.opcode.got) + return X86_BR_ABORT; switch (insn.opcode.bytes[0]) { case 0xf: diff --git a/arch/x86/kernel/kprobes/core.c b/arch/x86/kernel/kprobes/core.c index 67e6d19ef1be..f7e3cd50ece0 100644 --- a/arch/x86/kernel/kprobes/core.c +++ b/arch/x86/kernel/kprobes/core.c @@ -285,7 +285,7 @@ static int can_probe(unsigned long paddr) * normally used, we just go through if there is no kprobe. */ __addr = recover_probed_instruction(buf, addr); - kernel_insn_init(&insn, (void *)__addr); + kernel_insn_init(&insn, (void *)__addr, MAX_INSN_SIZE); insn_get_length(&insn); /* @@ -330,8 +330,10 @@ int __copy_instruction(u8 *dest, u8 *src) { struct insn insn; kprobe_opcode_t buf[MAX_INSN_SIZE]; + unsigned long recovered_insn = + recover_probed_instruction(buf, (unsigned long)src); - kernel_insn_init(&insn, (void *)recover_probed_instruction(buf, (unsigned long)src)); + kernel_insn_init(&insn, (void *)recovered_insn, MAX_INSN_SIZE); insn_get_length(&insn); /* Another subsystem puts a breakpoint, failed to recover */ if (insn.opcode.bytes[0] == BREAKPOINT_INSTRUCTION) @@ -342,7 +344,7 @@ int __copy_instruction(u8 *dest, u8 *src) if (insn_rip_relative(&insn)) { s64 newdisp; u8 *disp; - kernel_insn_init(&insn, dest); + kernel_insn_init(&insn, dest, insn.length); insn_get_displacement(&insn); /* * The copied instruction uses the %rip-relative addressing diff --git a/arch/x86/kernel/kprobes/opt.c b/arch/x86/kernel/kprobes/opt.c index f1314d0bcf0a..7c523bbf3dc8 100644 --- a/arch/x86/kernel/kprobes/opt.c +++ b/arch/x86/kernel/kprobes/opt.c @@ -251,13 +251,15 @@ static int can_optimize(unsigned long paddr) /* Decode instructions */ addr = paddr - offset; while (addr < paddr - offset + size) { /* Decode until function end */ + unsigned long recovered_insn; if (search_exception_tables(addr)) /* * Since some fixup code will jumps into this function, * we can't optimize kprobe in this function. */ return 0; - kernel_insn_init(&insn, (void *)recover_probed_instruction(buf, addr)); + recovered_insn = recover_probed_instruction(buf, addr); + kernel_insn_init(&insn, (void *)recovered_insn, MAX_INSN_SIZE); insn_get_length(&insn); /* Another subsystem puts a breakpoint */ if (insn.opcode.bytes[0] == BREAKPOINT_INSTRUCTION) diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c index ab08aa2276fb..214245d6b996 100644 --- a/arch/x86/kernel/setup.c +++ b/arch/x86/kernel/setup.c @@ -960,6 +960,8 @@ void __init setup_arch(char **cmdline_p) init_mm.end_data = (unsigned long) _edata; init_mm.brk = _brk_end; + mpx_mm_init(&init_mm); + code_resource.start = __pa_symbol(_text); code_resource.end = __pa_symbol(_etext)-1; data_resource.start = __pa_symbol(_etext); diff --git a/arch/x86/kernel/traps.c b/arch/x86/kernel/traps.c index 07ab8e9733c5..a9ae20579895 100644 --- a/arch/x86/kernel/traps.c +++ b/arch/x86/kernel/traps.c @@ -60,6 +60,7 @@ #include <asm/fixmap.h> #include <asm/mach_traps.h> #include <asm/alternative.h> +#include <asm/mpx.h> #ifdef CONFIG_X86_64 #include <asm/x86_init.h> @@ -228,7 +229,6 @@ dotraplinkage void do_##name(struct pt_regs *regs, long error_code) \ DO_ERROR(X86_TRAP_DE, SIGFPE, "divide error", divide_error) DO_ERROR(X86_TRAP_OF, SIGSEGV, "overflow", overflow) -DO_ERROR(X86_TRAP_BR, SIGSEGV, "bounds", bounds) DO_ERROR(X86_TRAP_UD, SIGILL, "invalid opcode", invalid_op) DO_ERROR(X86_TRAP_OLD_MF, SIGFPE, "coprocessor segment overrun",coprocessor_segment_overrun) DO_ERROR(X86_TRAP_TS, SIGSEGV, "invalid TSS", invalid_TSS) @@ -286,6 +286,89 @@ dotraplinkage void do_double_fault(struct pt_regs *regs, long error_code) } #endif +dotraplinkage void do_bounds(struct pt_regs *regs, long error_code) +{ + struct task_struct *tsk = current; + struct xsave_struct *xsave_buf; + enum ctx_state prev_state; + struct bndcsr *bndcsr; + siginfo_t *info; + + prev_state = exception_enter(); + if (notify_die(DIE_TRAP, "bounds", regs, error_code, + X86_TRAP_BR, SIGSEGV) == NOTIFY_STOP) + goto exit; + conditional_sti(regs); + + if (!user_mode(regs)) + die("bounds", regs, error_code); + + if (!cpu_feature_enabled(X86_FEATURE_MPX)) { + /* The exception is not from Intel MPX */ + goto exit_trap; + } + + /* + * We need to look at BNDSTATUS to resolve this exception. + * It is not directly accessible, though, so we need to + * do an xsave and then pull it out of the xsave buffer. + */ + fpu_save_init(&tsk->thread.fpu); + xsave_buf = &(tsk->thread.fpu.state->xsave); + bndcsr = get_xsave_addr(xsave_buf, XSTATE_BNDCSR); + if (!bndcsr) + goto exit_trap; + + /* + * The error code field of the BNDSTATUS register communicates status + * information of a bound range exception #BR or operation involving + * bound directory. + */ + switch (bndcsr->bndstatus & MPX_BNDSTA_ERROR_CODE) { + case 2: /* Bound directory has invalid entry. */ + if (mpx_handle_bd_fault(xsave_buf)) + goto exit_trap; + break; /* Success, it was handled */ + case 1: /* Bound violation. */ + info = mpx_generate_siginfo(regs, xsave_buf); + if (PTR_ERR(info)) { + /* + * We failed to decode the MPX instruction. Act as if + * the exception was not caused by MPX. + */ + goto exit_trap; + } + /* + * Success, we decoded the instruction and retrieved + * an 'info' containing the address being accessed + * which caused the exception. This information + * allows and application to possibly handle the + * #BR exception itself. + */ + do_trap(X86_TRAP_BR, SIGSEGV, "bounds", regs, error_code, info); + kfree(info); + break; + case 0: /* No exception caused by Intel MPX operations. */ + goto exit_trap; + default: + die("bounds", regs, error_code); + } + +exit: + exception_exit(prev_state); + return; +exit_trap: + /* + * This path out is for all the cases where we could not + * handle the exception in some way (like allocating a + * table or telling userspace about it. We will also end + * up here if the kernel has MPX turned off at compile + * time.. + */ + do_trap(X86_TRAP_BR, SIGSEGV, "bounds", regs, error_code, NULL); + exception_exit(prev_state); +} + dotraplinkage void do_general_protection(struct pt_regs *regs, long error_code) { diff --git a/arch/x86/kernel/uprobes.c b/arch/x86/kernel/uprobes.c index 5d1cbfe4ae58..8b96a947021f 100644 --- a/arch/x86/kernel/uprobes.c +++ b/arch/x86/kernel/uprobes.c @@ -219,7 +219,7 @@ static int uprobe_init_insn(struct arch_uprobe *auprobe, struct insn *insn, bool { u32 volatile *good_insns; - insn_init(insn, auprobe->insn, x86_64); + insn_init(insn, auprobe->insn, sizeof(auprobe->insn), x86_64); /* has the side-effect of processing the entire instruction */ insn_get_length(insn); if (WARN_ON_ONCE(!insn_complete(insn))) diff --git a/arch/x86/lib/insn.c b/arch/x86/lib/insn.c index 54fcffed28ed..2480978b31cc 100644 --- a/arch/x86/lib/insn.c +++ b/arch/x86/lib/insn.c @@ -28,7 +28,7 @@ /* Verify next sizeof(t) bytes can be on the same instruction */ #define validate_next(t, insn, n) \ - ((insn)->next_byte + sizeof(t) + n - (insn)->kaddr <= MAX_INSN_SIZE) + ((insn)->next_byte + sizeof(t) + n < (insn)->end_kaddr) #define __get_next(t, insn) \ ({ t r = *(t*)insn->next_byte; insn->next_byte += sizeof(t); r; }) @@ -50,10 +50,11 @@ * @kaddr: address (in kernel memory) of instruction (or copy thereof) * @x86_64: !0 for 64-bit kernel or 64-bit app */ -void insn_init(struct insn *insn, const void *kaddr, int x86_64) +void insn_init(struct insn *insn, const void *kaddr, int buf_len, int x86_64) { memset(insn, 0, sizeof(*insn)); insn->kaddr = kaddr; + insn->end_kaddr = kaddr + buf_len; insn->next_byte = kaddr; insn->x86_64 = x86_64 ? 1 : 0; insn->opnd_bytes = 4; diff --git a/arch/x86/mm/Makefile b/arch/x86/mm/Makefile index 6a19ad9f370d..ecfdc46a024a 100644 --- a/arch/x86/mm/Makefile +++ b/arch/x86/mm/Makefile @@ -30,3 +30,5 @@ obj-$(CONFIG_ACPI_NUMA) += srat.o obj-$(CONFIG_NUMA_EMU) += numa_emulation.o obj-$(CONFIG_MEMTEST) += memtest.o + +obj-$(CONFIG_X86_INTEL_MPX) += mpx.o diff --git a/arch/x86/mm/mpx.c b/arch/x86/mm/mpx.c new file mode 100644 index 000000000000..67ebf5751222 --- /dev/null +++ b/arch/x86/mm/mpx.c @@ -0,0 +1,928 @@ +/* + * mpx.c - Memory Protection eXtensions + * + * Copyright (c) 2014, Intel Corporation. + * Qiaowei Ren <qiaowei.ren@intel.com> + * Dave Hansen <dave.hansen@intel.com> + */ +#include <linux/kernel.h> +#include <linux/slab.h> +#include <linux/syscalls.h> +#include <linux/sched/sysctl.h> + +#include <asm/i387.h> +#include <asm/insn.h> +#include <asm/mman.h> +#include <asm/mmu_context.h> +#include <asm/mpx.h> +#include <asm/processor.h> +#include <asm/fpu-internal.h> + +static const char *mpx_mapping_name(struct vm_area_struct *vma) +{ + return "[mpx]"; +} + +static struct vm_operations_struct mpx_vma_ops = { + .name = mpx_mapping_name, +}; + +static int is_mpx_vma(struct vm_area_struct *vma) +{ + return (vma->vm_ops == &mpx_vma_ops); +} + +/* + * This is really a simplified "vm_mmap". it only handles MPX + * bounds tables (the bounds directory is user-allocated). + * + * Later on, we use the vma->vm_ops to uniquely identify these + * VMAs. + */ +static unsigned long mpx_mmap(unsigned long len) +{ + unsigned long ret; + unsigned long addr, pgoff; + struct mm_struct *mm = current->mm; + vm_flags_t vm_flags; + struct vm_area_struct *vma; + + /* Only bounds table and bounds directory can be allocated here */ + if (len != MPX_BD_SIZE_BYTES && len != MPX_BT_SIZE_BYTES) + return -EINVAL; + + down_write(&mm->mmap_sem); + + /* Too many mappings? */ + if (mm->map_count > sysctl_max_map_count) { + ret = -ENOMEM; + goto out; + } + + /* Obtain the address to map to. we verify (or select) it and ensure + * that it represents a valid section of the address space. + */ + addr = get_unmapped_area(NULL, 0, len, 0, MAP_ANONYMOUS | MAP_PRIVATE); + if (addr & ~PAGE_MASK) { + ret = addr; + goto out; + } + + vm_flags = VM_READ | VM_WRITE | VM_MPX | + mm->def_flags | VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC; + + |