| /* |
| * linux/arch/sh/kernel/ptrace.c |
| * |
| * Original x86 implementation: |
| * By Ross Biro 1/23/92 |
| * edited by Linus Torvalds |
| * |
| * SuperH version: Copyright (C) 1999, 2000 Kaz Kojima & Niibe Yutaka |
| * |
| */ |
| #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/slab.h> |
| #include <linux/security.h> |
| #include <linux/signal.h> |
| #include <linux/io.h> |
| #include <asm/uaccess.h> |
| #include <asm/pgtable.h> |
| #include <asm/system.h> |
| #include <asm/processor.h> |
| #include <asm/mmu_context.h> |
| |
| /* |
| * does not yet catch signals sent when the child dies. |
| * in exit.c or in signal.c. |
| */ |
| |
| /* |
| * 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; |
| } |
| |
| static void ptrace_disable_singlestep(struct task_struct *child) |
| { |
| clear_tsk_thread_flag(child, TIF_SINGLESTEP); |
| |
| /* |
| * Ensure the UBC is not programmed at the next context switch. |
| * |
| * Normally this is not needed but there are sequences such as |
| * singlestep, signal delivery, and continue that leave the |
| * ubc_pc non-zero leading to spurious SIGTRAPs. |
| */ |
| if (child->thread.ubc_pc != 0) { |
| ubc_usercnt -= 1; |
| child->thread.ubc_pc = 0; |
| } |
| } |
| |
| /* |
| * Called by kernel/ptrace.c when detaching.. |
| * |
| * Make sure single step bits etc are not set. |
| */ |
| void ptrace_disable(struct task_struct *child) |
| { |
| ptrace_disable_singlestep(child); |
| } |
| |
| long arch_ptrace(struct task_struct *child, long request, long addr, long data) |
| { |
| struct user * dummy = NULL; |
| int ret; |
| |
| switch (request) { |
| /* when I and D space are separate, these will need to be fixed. */ |
| case PTRACE_PEEKTEXT: /* read word at location addr. */ |
| case PTRACE_PEEKDATA: |
| ret = generic_ptrace_peekdata(child, addr, data); |
| break; |
| |
| /* 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 >= (long) &dummy->fpu && |
| addr < (long) &dummy->u_fpvalid) { |
| if (!tsk_used_math(child)) { |
| if (addr == (long)&dummy->fpu.fpscr) |
| tmp = FPSCR_INIT; |
| else |
| tmp = 0; |
| } else |
| tmp = ((long *)&child->thread.fpu) |
| [(addr - (long)&dummy->fpu) >> 2]; |
| } else if (addr == (long) &dummy->u_fpvalid) |
| tmp = !!tsk_used_math(child); |
| else |
| tmp = 0; |
| ret = put_user(tmp, (unsigned long __user *)data); |
| break; |
| } |
| |
| /* when I and D space are separate, this will have to be fixed. */ |
| case PTRACE_POKETEXT: /* write the word at location addr. */ |
| case PTRACE_POKEDATA: |
| ret = generic_ptrace_pokedata(child, addr, data); |
| 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 >= (long) &dummy->fpu && |
| addr < (long) &dummy->u_fpvalid) { |
| set_stopped_child_used_math(child); |
| ((long *)&child->thread.fpu) |
| [(addr - (long)&dummy->fpu) >> 2] = data; |
| ret = 0; |
| } else if (addr == (long) &dummy->u_fpvalid) { |
| conditional_stopped_child_used_math(data, child); |
| ret = 0; |
| } |
| break; |
| |
| case PTRACE_SYSCALL: /* continue and stop at next (return from) syscall */ |
| case PTRACE_CONT: { /* restart after signal. */ |
| ret = -EIO; |
| if (!valid_signal(data)) |
| break; |
| if (request == PTRACE_SYSCALL) |
| set_tsk_thread_flag(child, TIF_SYSCALL_TRACE); |
| else |
| clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE); |
| |
| ptrace_disable_singlestep(child); |
| |
| child->exit_code = data; |
| wake_up_process(child); |
| ret = 0; |
| break; |
| } |
| |
| /* |
| * make the child exit. Best I can do is send it a sigkill. |
| * perhaps it should be put in the status that it wants to |
| * exit. |
| */ |
| case PTRACE_KILL: { |
| ret = 0; |
| if (child->exit_state == EXIT_ZOMBIE) /* already dead */ |
| break; |
| ptrace_disable_singlestep(child); |
| child->exit_code = SIGKILL; |
| wake_up_process(child); |
| break; |
| } |
| |
| case PTRACE_SINGLESTEP: { /* set the trap flag. */ |
| long pc; |
| struct pt_regs *regs = NULL; |
| |
| ret = -EIO; |
| if (!valid_signal(data)) |
| break; |
| clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE); |
| if ((child->ptrace & PT_DTRACE) == 0) { |
| /* Spurious delayed TF traps may occur */ |
| child->ptrace |= PT_DTRACE; |
| } |
| |
| pc = get_stack_long(child, (long)®s->pc); |
| |
| /* Next scheduling will set up UBC */ |
| if (child->thread.ubc_pc == 0) |
| ubc_usercnt += 1; |
| child->thread.ubc_pc = pc; |
| |
| set_tsk_thread_flag(child, TIF_SINGLESTEP); |
| child->exit_code = data; |
| /* give it a chance to run. */ |
| wake_up_process(child); |
| ret = 0; |
| break; |
| } |
| |
| case PTRACE_DETACH: /* detach a process that was attached. */ |
| ret = ptrace_detach(child, data); |
| break; |
| |
| #ifdef CONFIG_SH_DSP |
| case PTRACE_GETDSPREGS: { |
| unsigned long dp; |
| |
| ret = -EIO; |
| dp = ((unsigned long) child) + THREAD_SIZE - |
| sizeof(struct pt_dspregs); |
| if (*((int *) (dp - 4)) == SR_FD) { |
| copy_to_user(addr, (void *) dp, |
| sizeof(struct pt_dspregs)); |
| ret = 0; |
| } |
| break; |
| } |
| |
| case PTRACE_SETDSPREGS: { |
| unsigned long dp; |
| |
| ret = -EIO; |
| dp = ((unsigned long) child) + THREAD_SIZE - |
| sizeof(struct pt_dspregs); |
| if (*((int *) (dp - 4)) == SR_FD) { |
| copy_from_user((void *) dp, addr, |
| sizeof(struct pt_dspregs)); |
| ret = 0; |
| } |
| break; |
| } |
| #endif |
| default: |
| ret = ptrace_request(child, request, addr, data); |
| break; |
| } |
| |
| return ret; |
| } |
| |
| asmlinkage void do_syscall_trace(void) |
| { |
| struct task_struct *tsk = current; |
| |
| if (!test_thread_flag(TIF_SYSCALL_TRACE) && |
| !test_thread_flag(TIF_SINGLESTEP)) |
| return; |
| if (!(tsk->ptrace & PT_PTRACED)) |
| return; |
| /* the 0x80 provides a way for the tracing parent to distinguish |
| between a syscall stop and SIGTRAP delivery */ |
| ptrace_notify(SIGTRAP | ((current->ptrace & PT_TRACESYSGOOD) && |
| !test_thread_flag(TIF_SINGLESTEP) ? 0x80 : 0)); |
| |
| /* |
| * this isn't the same as continuing with a signal, but it will do |
| * for normal use. strace only continues with a signal if the |
| * stopping signal is not SIGTRAP. -brl |
| */ |
| if (tsk->exit_code) { |
| send_sig(tsk->exit_code, tsk, 1); |
| tsk->exit_code = 0; |
| } |
| } |