| /* |
| * Copyright (C) 2000 Jeff Dike (jdike@karaya.com) |
| * Licensed under the GPL |
| */ |
| |
| #include "linux/sched.h" |
| #include "linux/mm.h" |
| #include "linux/errno.h" |
| #include "linux/smp_lock.h" |
| #include "linux/security.h" |
| #include "linux/ptrace.h" |
| #include "linux/audit.h" |
| #ifdef CONFIG_PROC_MM |
| #include "linux/proc_mm.h" |
| #endif |
| #include "asm/ptrace.h" |
| #include "asm/uaccess.h" |
| #include "kern_util.h" |
| #include "skas_ptrace.h" |
| #include "sysdep/ptrace.h" |
| |
| static inline void set_singlestepping(struct task_struct *child, int on) |
| { |
| if (on) |
| child->ptrace |= PT_DTRACE; |
| else |
| child->ptrace &= ~PT_DTRACE; |
| child->thread.singlestep_syscall = 0; |
| |
| #ifdef SUBARCH_SET_SINGLESTEPPING |
| SUBARCH_SET_SINGLESTEPPING(child, on) |
| #endif |
| } |
| |
| /* |
| * Called by kernel/ptrace.c when detaching.. |
| */ |
| void ptrace_disable(struct task_struct *child) |
| { |
| set_singlestepping(child,0); |
| } |
| |
| extern int peek_user(struct task_struct * child, long addr, long data); |
| extern int poke_user(struct task_struct * child, long addr, long data); |
| |
| long sys_ptrace(long request, long pid, long addr, long data) |
| { |
| struct task_struct *child; |
| int i, ret; |
| |
| lock_kernel(); |
| ret = -EPERM; |
| if (request == PTRACE_TRACEME) { |
| /* are we already being traced? */ |
| if (current->ptrace & PT_PTRACED) |
| goto out; |
| |
| ret = security_ptrace(current->parent, current); |
| if (ret) |
| goto out; |
| |
| /* set the ptrace bit in the process flags. */ |
| current->ptrace |= PT_PTRACED; |
| ret = 0; |
| goto out; |
| } |
| ret = -ESRCH; |
| read_lock(&tasklist_lock); |
| child = find_task_by_pid(pid); |
| if (child) |
| get_task_struct(child); |
| read_unlock(&tasklist_lock); |
| if (!child) |
| goto out; |
| |
| ret = -EPERM; |
| if (pid == 1) /* you may not mess with init */ |
| goto out_tsk; |
| |
| if (request == PTRACE_ATTACH) { |
| ret = ptrace_attach(child); |
| goto out_tsk; |
| } |
| |
| #ifdef SUBACH_PTRACE_SPECIAL |
| SUBARCH_PTRACE_SPECIAL(child,request,addr,data) |
| #endif |
| |
| ret = ptrace_check_attach(child, request == PTRACE_KILL); |
| if (ret < 0) |
| goto out_tsk; |
| |
| 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: { |
| unsigned long tmp; |
| int copied; |
| |
| ret = -EIO; |
| copied = access_process_vm(child, addr, &tmp, sizeof(tmp), 0); |
| if (copied != sizeof(tmp)) |
| break; |
| ret = put_user(tmp, (unsigned long __user *) data); |
| break; |
| } |
| |
| /* read the word at location addr in the USER area. */ |
| case PTRACE_PEEKUSR: |
| ret = peek_user(child, addr, 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 = -EIO; |
| if (access_process_vm(child, addr, &data, sizeof(data), |
| 1) != sizeof(data)) |
| break; |
| ret = 0; |
| break; |
| |
| case PTRACE_POKEUSR: /* write the word at location addr in the USER area */ |
| ret = poke_user(child, addr, data); |
| 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; |
| |
| set_singlestepping(child, 0); |
| if (request == PTRACE_SYSCALL) { |
| set_tsk_thread_flag(child, TIF_SYSCALL_TRACE); |
| } |
| else { |
| clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE); |
| } |
| 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; |
| |
| set_singlestepping(child, 0); |
| child->exit_code = SIGKILL; |
| wake_up_process(child); |
| break; |
| } |
| |
| case PTRACE_SINGLESTEP: { /* set the trap flag. */ |
| ret = -EIO; |
| if (!valid_signal(data)) |
| break; |
| clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE); |
| set_singlestepping(child, 1); |
| 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 PTRACE_GETREGS |
| case PTRACE_GETREGS: { /* Get all gp regs from the child. */ |
| if (!access_ok(VERIFY_WRITE, (unsigned long *)data, |
| MAX_REG_OFFSET)) { |
| ret = -EIO; |
| break; |
| } |
| for ( i = 0; i < MAX_REG_OFFSET; i += sizeof(long) ) { |
| __put_user(getreg(child, i), |
| (unsigned long __user *) data); |
| data += sizeof(long); |
| } |
| ret = 0; |
| break; |
| } |
| #endif |
| #ifdef PTRACE_SETREGS |
| case PTRACE_SETREGS: { /* Set all gp regs in the child. */ |
| unsigned long tmp = 0; |
| if (!access_ok(VERIFY_READ, (unsigned *)data, |
| MAX_REG_OFFSET)) { |
| ret = -EIO; |
| break; |
| } |
| for ( i = 0; i < MAX_REG_OFFSET; i += sizeof(long) ) { |
| __get_user(tmp, (unsigned long __user *) data); |
| putreg(child, i, tmp); |
| data += sizeof(long); |
| } |
| ret = 0; |
| break; |
| } |
| #endif |
| #ifdef PTRACE_GETFPREGS |
| case PTRACE_GETFPREGS: /* Get the child FPU state. */ |
| ret = get_fpregs(data, child); |
| break; |
| #endif |
| #ifdef PTRACE_SETFPREGS |
| case PTRACE_SETFPREGS: /* Set the child FPU state. */ |
| ret = set_fpregs(data, child); |
| break; |
| #endif |
| #ifdef PTRACE_GETFPXREGS |
| case PTRACE_GETFPXREGS: /* Get the child FPU state. */ |
| ret = get_fpxregs(data, child); |
| break; |
| #endif |
| #ifdef PTRACE_SETFPXREGS |
| case PTRACE_SETFPXREGS: /* Set the child FPU state. */ |
| ret = set_fpxregs(data, child); |
| break; |
| #endif |
| case PTRACE_FAULTINFO: { |
| /* Take the info from thread->arch->faultinfo, |
| * but transfer max. sizeof(struct ptrace_faultinfo). |
| * On i386, ptrace_faultinfo is smaller! |
| */ |
| ret = copy_to_user((unsigned long __user *) data, |
| &child->thread.arch.faultinfo, |
| sizeof(struct ptrace_faultinfo)); |
| if(ret) |
| break; |
| break; |
| } |
| |
| #ifdef PTRACE_LDT |
| case PTRACE_LDT: { |
| struct ptrace_ldt ldt; |
| |
| if(copy_from_user(&ldt, (unsigned long __user *) data, |
| sizeof(ldt))){ |
| ret = -EIO; |
| break; |
| } |
| |
| /* This one is confusing, so just punt and return -EIO for |
| * now |
| */ |
| ret = -EIO; |
| break; |
| } |
| #endif |
| #ifdef CONFIG_PROC_MM |
| case PTRACE_SWITCH_MM: { |
| struct mm_struct *old = child->mm; |
| struct mm_struct *new = proc_mm_get_mm(data); |
| |
| if(IS_ERR(new)){ |
| ret = PTR_ERR(new); |
| break; |
| } |
| |
| atomic_inc(&new->mm_users); |
| child->mm = new; |
| child->active_mm = new; |
| mmput(old); |
| ret = 0; |
| break; |
| } |
| #endif |
| default: |
| ret = ptrace_request(child, request, addr, data); |
| break; |
| } |
| out_tsk: |
| put_task_struct(child); |
| out: |
| unlock_kernel(); |
| return ret; |
| } |
| |
| void send_sigtrap(struct task_struct *tsk, union uml_pt_regs *regs, |
| int error_code) |
| { |
| struct siginfo info; |
| |
| memset(&info, 0, sizeof(info)); |
| info.si_signo = SIGTRAP; |
| info.si_code = TRAP_BRKPT; |
| |
| /* User-mode eip? */ |
| info.si_addr = UPT_IS_USER(regs) ? (void __user *) UPT_IP(regs) : NULL; |
| |
| /* Send us the fakey SIGTRAP */ |
| force_sig_info(SIGTRAP, &info, tsk); |
| } |
| |
| /* XXX Check PT_DTRACE vs TIF_SINGLESTEP for singlestepping check and |
| * PT_PTRACED vs TIF_SYSCALL_TRACE for syscall tracing check |
| */ |
| void syscall_trace(union uml_pt_regs *regs, int entryexit) |
| { |
| int is_singlestep = (current->ptrace & PT_DTRACE) && entryexit; |
| int tracesysgood; |
| |
| if (unlikely(current->audit_context)) { |
| if (!entryexit) |
| audit_syscall_entry(current, |
| HOST_AUDIT_ARCH, |
| UPT_SYSCALL_NR(regs), |
| UPT_SYSCALL_ARG1(regs), |
| UPT_SYSCALL_ARG2(regs), |
| UPT_SYSCALL_ARG3(regs), |
| UPT_SYSCALL_ARG4(regs)); |
| else { |
| int res = UPT_SYSCALL_RET(regs); |
| audit_syscall_exit(current, AUDITSC_RESULT(res), |
| res); |
| } |
| } |
| |
| /* Fake a debug trap */ |
| if (is_singlestep) |
| send_sigtrap(current, regs, 0); |
| |
| if (!test_thread_flag(TIF_SYSCALL_TRACE)) |
| return; |
| |
| if (!(current->ptrace & PT_PTRACED)) |
| return; |
| |
| /* the 0x80 provides a way for the tracing parent to distinguish |
| between a syscall stop and SIGTRAP delivery */ |
| tracesysgood = (current->ptrace & PT_TRACESYSGOOD); |
| ptrace_notify(SIGTRAP | (tracesysgood ? 0x80 : 0)); |
| |
| if (entryexit) /* force do_signal() --> is_syscall() */ |
| set_thread_flag(TIF_SIGPENDING); |
| |
| /* 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 (current->exit_code) { |
| send_sig(current->exit_code, current, 1); |
| current->exit_code = 0; |
| } |
| } |
| |
| /* |
| * Overrides for Emacs so that we follow Linus's tabbing style. |
| * Emacs will notice this stuff at the end of the file and automatically |
| * adjust the settings for this buffer only. This must remain at the end |
| * of the file. |
| * --------------------------------------------------------------------------- |
| * Local variables: |
| * c-file-style: "linux" |
| * End: |
| */ |