|  | /* | 
|  | * SuperH process tracing | 
|  | * | 
|  | * Copyright (C) 1999, 2000  Kaz Kojima & Niibe Yutaka | 
|  | * Copyright (C) 2002 - 2009  Paul Mundt | 
|  | * | 
|  | * Audit support by Yuichi Nakamura <ynakam@hitachisoft.jp> | 
|  | * | 
|  | * This file is subject to the terms and conditions of the GNU General Public | 
|  | * License.  See the file "COPYING" in the main directory of this archive | 
|  | * for more details. | 
|  | */ | 
|  | #include <linux/kernel.h> | 
|  | #include <linux/sched.h> | 
|  | #include <linux/mm.h> | 
|  | #include <linux/smp.h> | 
|  | #include <linux/errno.h> | 
|  | #include <linux/ptrace.h> | 
|  | #include <linux/user.h> | 
|  | #include <linux/security.h> | 
|  | #include <linux/signal.h> | 
|  | #include <linux/io.h> | 
|  | #include <linux/audit.h> | 
|  | #include <linux/seccomp.h> | 
|  | #include <linux/tracehook.h> | 
|  | #include <linux/elf.h> | 
|  | #include <linux/regset.h> | 
|  | #include <linux/hw_breakpoint.h> | 
|  | #include <asm/uaccess.h> | 
|  | #include <asm/pgtable.h> | 
|  | #include <asm/system.h> | 
|  | #include <asm/processor.h> | 
|  | #include <asm/mmu_context.h> | 
|  | #include <asm/syscalls.h> | 
|  | #include <asm/fpu.h> | 
|  |  | 
|  | #define CREATE_TRACE_POINTS | 
|  | #include <trace/events/syscalls.h> | 
|  |  | 
|  | /* | 
|  | * This routine will get a word off of the process kernel stack. | 
|  | */ | 
|  | static inline int get_stack_long(struct task_struct *task, int offset) | 
|  | { | 
|  | unsigned char *stack; | 
|  |  | 
|  | stack = (unsigned char *)task_pt_regs(task); | 
|  | stack += offset; | 
|  | return (*((int *)stack)); | 
|  | } | 
|  |  | 
|  | /* | 
|  | * This routine will put a word on the process kernel stack. | 
|  | */ | 
|  | static inline int put_stack_long(struct task_struct *task, int offset, | 
|  | unsigned long data) | 
|  | { | 
|  | unsigned char *stack; | 
|  |  | 
|  | stack = (unsigned char *)task_pt_regs(task); | 
|  | stack += offset; | 
|  | *(unsigned long *) stack = data; | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | void ptrace_triggered(struct perf_event *bp, int nmi, | 
|  | struct perf_sample_data *data, struct pt_regs *regs) | 
|  | { | 
|  | struct perf_event_attr attr; | 
|  |  | 
|  | /* | 
|  | * Disable the breakpoint request here since ptrace has defined a | 
|  | * one-shot behaviour for breakpoint exceptions. | 
|  | */ | 
|  | attr = bp->attr; | 
|  | attr.disabled = true; | 
|  | modify_user_hw_breakpoint(bp, &attr); | 
|  | } | 
|  |  | 
|  | static int set_single_step(struct task_struct *tsk, unsigned long addr) | 
|  | { | 
|  | struct thread_struct *thread = &tsk->thread; | 
|  | struct perf_event *bp; | 
|  | struct perf_event_attr attr; | 
|  |  | 
|  | bp = thread->ptrace_bps[0]; | 
|  | if (!bp) { | 
|  | ptrace_breakpoint_init(&attr); | 
|  |  | 
|  | attr.bp_addr = addr; | 
|  | attr.bp_len = HW_BREAKPOINT_LEN_2; | 
|  | attr.bp_type = HW_BREAKPOINT_R; | 
|  |  | 
|  | bp = register_user_hw_breakpoint(&attr, ptrace_triggered, tsk); | 
|  | if (IS_ERR(bp)) | 
|  | return PTR_ERR(bp); | 
|  |  | 
|  | thread->ptrace_bps[0] = bp; | 
|  | } else { | 
|  | int err; | 
|  |  | 
|  | attr = bp->attr; | 
|  | attr.bp_addr = addr; | 
|  | /* reenable breakpoint */ | 
|  | attr.disabled = false; | 
|  | err = modify_user_hw_breakpoint(bp, &attr); | 
|  | if (unlikely(err)) | 
|  | return err; | 
|  | } | 
|  |  | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | void user_enable_single_step(struct task_struct *child) | 
|  | { | 
|  | unsigned long pc = get_stack_long(child, offsetof(struct pt_regs, pc)); | 
|  |  | 
|  | set_tsk_thread_flag(child, TIF_SINGLESTEP); | 
|  |  | 
|  | set_single_step(child, pc); | 
|  | } | 
|  |  | 
|  | void user_disable_single_step(struct task_struct *child) | 
|  | { | 
|  | clear_tsk_thread_flag(child, TIF_SINGLESTEP); | 
|  | } | 
|  |  | 
|  | /* | 
|  | * Called by kernel/ptrace.c when detaching.. | 
|  | * | 
|  | * Make sure single step bits etc are not set. | 
|  | */ | 
|  | void ptrace_disable(struct task_struct *child) | 
|  | { | 
|  | user_disable_single_step(child); | 
|  | } | 
|  |  | 
|  | static int genregs_get(struct task_struct *target, | 
|  | const struct user_regset *regset, | 
|  | unsigned int pos, unsigned int count, | 
|  | void *kbuf, void __user *ubuf) | 
|  | { | 
|  | const struct pt_regs *regs = task_pt_regs(target); | 
|  | int ret; | 
|  |  | 
|  | ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf, | 
|  | regs->regs, | 
|  | 0, 16 * sizeof(unsigned long)); | 
|  | if (!ret) | 
|  | /* PC, PR, SR, GBR, MACH, MACL, TRA */ | 
|  | ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf, | 
|  | ®s->pc, | 
|  | offsetof(struct pt_regs, pc), | 
|  | sizeof(struct pt_regs)); | 
|  | if (!ret) | 
|  | ret = user_regset_copyout_zero(&pos, &count, &kbuf, &ubuf, | 
|  | sizeof(struct pt_regs), -1); | 
|  |  | 
|  | return ret; | 
|  | } | 
|  |  | 
|  | static int genregs_set(struct task_struct *target, | 
|  | const struct user_regset *regset, | 
|  | unsigned int pos, unsigned int count, | 
|  | const void *kbuf, const void __user *ubuf) | 
|  | { | 
|  | struct pt_regs *regs = task_pt_regs(target); | 
|  | int ret; | 
|  |  | 
|  | ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, | 
|  | regs->regs, | 
|  | 0, 16 * sizeof(unsigned long)); | 
|  | if (!ret && count > 0) | 
|  | ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, | 
|  | ®s->pc, | 
|  | offsetof(struct pt_regs, pc), | 
|  | sizeof(struct pt_regs)); | 
|  | if (!ret) | 
|  | ret = user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf, | 
|  | sizeof(struct pt_regs), -1); | 
|  |  | 
|  | return ret; | 
|  | } | 
|  |  | 
|  | #ifdef CONFIG_SH_FPU | 
|  | int fpregs_get(struct task_struct *target, | 
|  | const struct user_regset *regset, | 
|  | unsigned int pos, unsigned int count, | 
|  | void *kbuf, void __user *ubuf) | 
|  | { | 
|  | int ret; | 
|  |  | 
|  | ret = init_fpu(target); | 
|  | if (ret) | 
|  | return ret; | 
|  |  | 
|  | if ((boot_cpu_data.flags & CPU_HAS_FPU)) | 
|  | return user_regset_copyout(&pos, &count, &kbuf, &ubuf, | 
|  | &target->thread.xstate->hardfpu, 0, -1); | 
|  |  | 
|  | return user_regset_copyout(&pos, &count, &kbuf, &ubuf, | 
|  | &target->thread.xstate->softfpu, 0, -1); | 
|  | } | 
|  |  | 
|  | static int fpregs_set(struct task_struct *target, | 
|  | const struct user_regset *regset, | 
|  | unsigned int pos, unsigned int count, | 
|  | const void *kbuf, const void __user *ubuf) | 
|  | { | 
|  | int ret; | 
|  |  | 
|  | ret = init_fpu(target); | 
|  | if (ret) | 
|  | return ret; | 
|  |  | 
|  | set_stopped_child_used_math(target); | 
|  |  | 
|  | if ((boot_cpu_data.flags & CPU_HAS_FPU)) | 
|  | return user_regset_copyin(&pos, &count, &kbuf, &ubuf, | 
|  | &target->thread.xstate->hardfpu, 0, -1); | 
|  |  | 
|  | return user_regset_copyin(&pos, &count, &kbuf, &ubuf, | 
|  | &target->thread.xstate->softfpu, 0, -1); | 
|  | } | 
|  |  | 
|  | static int fpregs_active(struct task_struct *target, | 
|  | const struct user_regset *regset) | 
|  | { | 
|  | return tsk_used_math(target) ? regset->n : 0; | 
|  | } | 
|  | #endif | 
|  |  | 
|  | #ifdef CONFIG_SH_DSP | 
|  | static int dspregs_get(struct task_struct *target, | 
|  | const struct user_regset *regset, | 
|  | unsigned int pos, unsigned int count, | 
|  | void *kbuf, void __user *ubuf) | 
|  | { | 
|  | const struct pt_dspregs *regs = | 
|  | (struct pt_dspregs *)&target->thread.dsp_status.dsp_regs; | 
|  | int ret; | 
|  |  | 
|  | ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf, regs, | 
|  | 0, sizeof(struct pt_dspregs)); | 
|  | if (!ret) | 
|  | ret = user_regset_copyout_zero(&pos, &count, &kbuf, &ubuf, | 
|  | sizeof(struct pt_dspregs), -1); | 
|  |  | 
|  | return ret; | 
|  | } | 
|  |  | 
|  | static int dspregs_set(struct task_struct *target, | 
|  | const struct user_regset *regset, | 
|  | unsigned int pos, unsigned int count, | 
|  | const void *kbuf, const void __user *ubuf) | 
|  | { | 
|  | struct pt_dspregs *regs = | 
|  | (struct pt_dspregs *)&target->thread.dsp_status.dsp_regs; | 
|  | int ret; | 
|  |  | 
|  | ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, regs, | 
|  | 0, sizeof(struct pt_dspregs)); | 
|  | if (!ret) | 
|  | ret = user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf, | 
|  | sizeof(struct pt_dspregs), -1); | 
|  |  | 
|  | return ret; | 
|  | } | 
|  |  | 
|  | static int dspregs_active(struct task_struct *target, | 
|  | const struct user_regset *regset) | 
|  | { | 
|  | struct pt_regs *regs = task_pt_regs(target); | 
|  |  | 
|  | return regs->sr & SR_DSP ? regset->n : 0; | 
|  | } | 
|  | #endif | 
|  |  | 
|  | const struct pt_regs_offset regoffset_table[] = { | 
|  | REGS_OFFSET_NAME(0), | 
|  | REGS_OFFSET_NAME(1), | 
|  | REGS_OFFSET_NAME(2), | 
|  | REGS_OFFSET_NAME(3), | 
|  | REGS_OFFSET_NAME(4), | 
|  | REGS_OFFSET_NAME(5), | 
|  | REGS_OFFSET_NAME(6), | 
|  | REGS_OFFSET_NAME(7), | 
|  | REGS_OFFSET_NAME(8), | 
|  | REGS_OFFSET_NAME(9), | 
|  | REGS_OFFSET_NAME(10), | 
|  | REGS_OFFSET_NAME(11), | 
|  | REGS_OFFSET_NAME(12), | 
|  | REGS_OFFSET_NAME(13), | 
|  | REGS_OFFSET_NAME(14), | 
|  | REGS_OFFSET_NAME(15), | 
|  | REG_OFFSET_NAME(pc), | 
|  | REG_OFFSET_NAME(pr), | 
|  | REG_OFFSET_NAME(sr), | 
|  | REG_OFFSET_NAME(gbr), | 
|  | REG_OFFSET_NAME(mach), | 
|  | REG_OFFSET_NAME(macl), | 
|  | REG_OFFSET_NAME(tra), | 
|  | REG_OFFSET_END, | 
|  | }; | 
|  |  | 
|  | /* | 
|  | * These are our native regset flavours. | 
|  | */ | 
|  | enum sh_regset { | 
|  | REGSET_GENERAL, | 
|  | #ifdef CONFIG_SH_FPU | 
|  | REGSET_FPU, | 
|  | #endif | 
|  | #ifdef CONFIG_SH_DSP | 
|  | REGSET_DSP, | 
|  | #endif | 
|  | }; | 
|  |  | 
|  | static const struct user_regset sh_regsets[] = { | 
|  | /* | 
|  | * Format is: | 
|  | *	R0 --> R15 | 
|  | *	PC, PR, SR, GBR, MACH, MACL, TRA | 
|  | */ | 
|  | [REGSET_GENERAL] = { | 
|  | .core_note_type	= NT_PRSTATUS, | 
|  | .n		= ELF_NGREG, | 
|  | .size		= sizeof(long), | 
|  | .align		= sizeof(long), | 
|  | .get		= genregs_get, | 
|  | .set		= genregs_set, | 
|  | }, | 
|  |  | 
|  | #ifdef CONFIG_SH_FPU | 
|  | [REGSET_FPU] = { | 
|  | .core_note_type	= NT_PRFPREG, | 
|  | .n		= sizeof(struct user_fpu_struct) / sizeof(long), | 
|  | .size		= sizeof(long), | 
|  | .align		= sizeof(long), | 
|  | .get		= fpregs_get, | 
|  | .set		= fpregs_set, | 
|  | .active		= fpregs_active, | 
|  | }, | 
|  | #endif | 
|  |  | 
|  | #ifdef CONFIG_SH_DSP | 
|  | [REGSET_DSP] = { | 
|  | .n		= sizeof(struct pt_dspregs) / sizeof(long), | 
|  | .size		= sizeof(long), | 
|  | .align		= sizeof(long), | 
|  | .get		= dspregs_get, | 
|  | .set		= dspregs_set, | 
|  | .active		= dspregs_active, | 
|  | }, | 
|  | #endif | 
|  | }; | 
|  |  | 
|  | static const struct user_regset_view user_sh_native_view = { | 
|  | .name		= "sh", | 
|  | .e_machine	= EM_SH, | 
|  | .regsets	= sh_regsets, | 
|  | .n		= ARRAY_SIZE(sh_regsets), | 
|  | }; | 
|  |  | 
|  | const struct user_regset_view *task_user_regset_view(struct task_struct *task) | 
|  | { | 
|  | return &user_sh_native_view; | 
|  | } | 
|  |  | 
|  | long arch_ptrace(struct task_struct *child, long request, | 
|  | unsigned long addr, unsigned long data) | 
|  | { | 
|  | unsigned long __user *datap = (unsigned long __user *)data; | 
|  | int ret; | 
|  |  | 
|  | switch (request) { | 
|  | /* read the word at location addr in the USER area. */ | 
|  | case PTRACE_PEEKUSR: { | 
|  | unsigned long tmp; | 
|  |  | 
|  | ret = -EIO; | 
|  | if ((addr & 3) || addr < 0 || | 
|  | addr > sizeof(struct user) - 3) | 
|  | break; | 
|  |  | 
|  | if (addr < sizeof(struct pt_regs)) | 
|  | tmp = get_stack_long(child, addr); | 
|  | else if (addr >= offsetof(struct user, fpu) && | 
|  | addr < offsetof(struct user, u_fpvalid)) { | 
|  | if (!tsk_used_math(child)) { | 
|  | if (addr == offsetof(struct user, fpu.fpscr)) | 
|  | tmp = FPSCR_INIT; | 
|  | else | 
|  | tmp = 0; | 
|  | } else { | 
|  | unsigned long index; | 
|  | ret = init_fpu(child); | 
|  | if (ret) | 
|  | break; | 
|  | index = addr - offsetof(struct user, fpu); | 
|  | tmp = ((unsigned long *)child->thread.xstate) | 
|  | [index >> 2]; | 
|  | } | 
|  | } else if (addr == offsetof(struct user, u_fpvalid)) | 
|  | tmp = !!tsk_used_math(child); | 
|  | else if (addr == PT_TEXT_ADDR) | 
|  | tmp = child->mm->start_code; | 
|  | else if (addr == PT_DATA_ADDR) | 
|  | tmp = child->mm->start_data; | 
|  | else if (addr == PT_TEXT_END_ADDR) | 
|  | tmp = child->mm->end_code; | 
|  | else if (addr == PT_TEXT_LEN) | 
|  | tmp = child->mm->end_code - child->mm->start_code; | 
|  | else | 
|  | tmp = 0; | 
|  | ret = put_user(tmp, datap); | 
|  | break; | 
|  | } | 
|  |  | 
|  | case PTRACE_POKEUSR: /* write the word at location addr in the USER area */ | 
|  | ret = -EIO; | 
|  | if ((addr & 3) || addr < 0 || | 
|  | addr > sizeof(struct user) - 3) | 
|  | break; | 
|  |  | 
|  | if (addr < sizeof(struct pt_regs)) | 
|  | ret = put_stack_long(child, addr, data); | 
|  | else if (addr >= offsetof(struct user, fpu) && | 
|  | addr < offsetof(struct user, u_fpvalid)) { | 
|  | unsigned long index; | 
|  | ret = init_fpu(child); | 
|  | if (ret) | 
|  | break; | 
|  | index = addr - offsetof(struct user, fpu); | 
|  | set_stopped_child_used_math(child); | 
|  | ((unsigned long *)child->thread.xstate) | 
|  | [index >> 2] = data; | 
|  | ret = 0; | 
|  | } else if (addr == offsetof(struct user, u_fpvalid)) { | 
|  | conditional_stopped_child_used_math(data, child); | 
|  | ret = 0; | 
|  | } | 
|  | break; | 
|  |  | 
|  | case PTRACE_GETREGS: | 
|  | return copy_regset_to_user(child, &user_sh_native_view, | 
|  | REGSET_GENERAL, | 
|  | 0, sizeof(struct pt_regs), | 
|  | datap); | 
|  | case PTRACE_SETREGS: | 
|  | return copy_regset_from_user(child, &user_sh_native_view, | 
|  | REGSET_GENERAL, | 
|  | 0, sizeof(struct pt_regs), | 
|  | datap); | 
|  | #ifdef CONFIG_SH_FPU | 
|  | case PTRACE_GETFPREGS: | 
|  | return copy_regset_to_user(child, &user_sh_native_view, | 
|  | REGSET_FPU, | 
|  | 0, sizeof(struct user_fpu_struct), | 
|  | datap); | 
|  | case PTRACE_SETFPREGS: | 
|  | return copy_regset_from_user(child, &user_sh_native_view, | 
|  | REGSET_FPU, | 
|  | 0, sizeof(struct user_fpu_struct), | 
|  | datap); | 
|  | #endif | 
|  | #ifdef CONFIG_SH_DSP | 
|  | case PTRACE_GETDSPREGS: | 
|  | return copy_regset_to_user(child, &user_sh_native_view, | 
|  | REGSET_DSP, | 
|  | 0, sizeof(struct pt_dspregs), | 
|  | datap); | 
|  | case PTRACE_SETDSPREGS: | 
|  | return copy_regset_from_user(child, &user_sh_native_view, | 
|  | REGSET_DSP, | 
|  | 0, sizeof(struct pt_dspregs), | 
|  | datap); | 
|  | #endif | 
|  | default: | 
|  | ret = ptrace_request(child, request, addr, data); | 
|  | break; | 
|  | } | 
|  |  | 
|  | return ret; | 
|  | } | 
|  |  | 
|  | static inline int audit_arch(void) | 
|  | { | 
|  | int arch = EM_SH; | 
|  |  | 
|  | #ifdef CONFIG_CPU_LITTLE_ENDIAN | 
|  | arch |= __AUDIT_ARCH_LE; | 
|  | #endif | 
|  |  | 
|  | return arch; | 
|  | } | 
|  |  | 
|  | asmlinkage long do_syscall_trace_enter(struct pt_regs *regs) | 
|  | { | 
|  | long ret = 0; | 
|  |  | 
|  | secure_computing(regs->regs[0]); | 
|  |  | 
|  | if (test_thread_flag(TIF_SYSCALL_TRACE) && | 
|  | tracehook_report_syscall_entry(regs)) | 
|  | /* | 
|  | * Tracing decided this syscall should not happen. | 
|  | * We'll return a bogus call number to get an ENOSYS | 
|  | * error, but leave the original number in regs->regs[0]. | 
|  | */ | 
|  | ret = -1L; | 
|  |  | 
|  | if (unlikely(test_thread_flag(TIF_SYSCALL_TRACEPOINT))) | 
|  | trace_sys_enter(regs, regs->regs[0]); | 
|  |  | 
|  | if (unlikely(current->audit_context)) | 
|  | audit_syscall_entry(audit_arch(), regs->regs[3], | 
|  | regs->regs[4], regs->regs[5], | 
|  | regs->regs[6], regs->regs[7]); | 
|  |  | 
|  | return ret ?: regs->regs[0]; | 
|  | } | 
|  |  | 
|  | asmlinkage void do_syscall_trace_leave(struct pt_regs *regs) | 
|  | { | 
|  | int step; | 
|  |  | 
|  | if (unlikely(current->audit_context)) | 
|  | audit_syscall_exit(AUDITSC_RESULT(regs->regs[0]), | 
|  | regs->regs[0]); | 
|  |  | 
|  | if (unlikely(test_thread_flag(TIF_SYSCALL_TRACEPOINT))) | 
|  | trace_sys_exit(regs, regs->regs[0]); | 
|  |  | 
|  | step = test_thread_flag(TIF_SINGLESTEP); | 
|  | if (step || test_thread_flag(TIF_SYSCALL_TRACE)) | 
|  | tracehook_report_syscall_exit(regs, step); | 
|  | } |