2 * Copyright (C) 2000 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
3 * Licensed under the GPL
6 #include "linux/audit.h"
7 #include "linux/ptrace.h"
8 #include "linux/sched.h"
9 #include "asm/uaccess.h"
10 #include "skas_ptrace.h"
14 void user_enable_single_step(struct task_struct *child)
16 child->ptrace |= PT_DTRACE;
17 child->thread.singlestep_syscall = 0;
19 #ifdef SUBARCH_SET_SINGLESTEPPING
20 SUBARCH_SET_SINGLESTEPPING(child, 1);
24 void user_disable_single_step(struct task_struct *child)
26 child->ptrace &= ~PT_DTRACE;
27 child->thread.singlestep_syscall = 0;
29 #ifdef SUBARCH_SET_SINGLESTEPPING
30 SUBARCH_SET_SINGLESTEPPING(child, 0);
35 * Called by kernel/ptrace.c when detaching..
37 void ptrace_disable(struct task_struct *child)
39 user_disable_single_step(child);
42 extern int peek_user(struct task_struct * child, long addr, long data);
43 extern int poke_user(struct task_struct * child, long addr, long data);
45 long arch_ptrace(struct task_struct *child, long request, long addr, long data)
48 unsigned long __user *p = (void __user *)(unsigned long)data;
51 /* read word at location addr. */
54 ret = generic_ptrace_peekdata(child, addr, data);
57 /* read the word at location addr in the USER area. */
59 ret = peek_user(child, addr, data);
62 /* write the word at location addr. */
65 ret = generic_ptrace_pokedata(child, addr, data);
68 /* write the word at location addr in the USER area */
70 ret = poke_user(child, addr, data);
74 case PTRACE_SYSEMU_SINGLESTEP:
79 case PTRACE_GETREGS: { /* Get all gp regs from the child. */
80 if (!access_ok(VERIFY_WRITE, p, MAX_REG_OFFSET)) {
84 for ( i = 0; i < MAX_REG_OFFSET; i += sizeof(long) ) {
85 __put_user(getreg(child, i), p);
93 case PTRACE_SETREGS: { /* Set all gp regs in the child. */
94 unsigned long tmp = 0;
95 if (!access_ok(VERIFY_READ, p, MAX_REG_OFFSET)) {
99 for ( i = 0; i < MAX_REG_OFFSET; i += sizeof(long) ) {
101 putreg(child, i, tmp);
108 #ifdef PTRACE_GETFPREGS
109 case PTRACE_GETFPREGS: /* Get the child FPU state. */
110 ret = get_fpregs((struct user_i387_struct __user *) data,
114 #ifdef PTRACE_SETFPREGS
115 case PTRACE_SETFPREGS: /* Set the child FPU state. */
116 ret = set_fpregs((struct user_i387_struct __user *) data,
120 case PTRACE_GET_THREAD_AREA:
121 ret = ptrace_get_thread_area(child, addr,
122 (struct user_desc __user *) data);
125 case PTRACE_SET_THREAD_AREA:
126 ret = ptrace_set_thread_area(child, addr,
127 (struct user_desc __user *) data);
130 case PTRACE_FAULTINFO: {
132 * Take the info from thread->arch->faultinfo,
133 * but transfer max. sizeof(struct ptrace_faultinfo).
134 * On i386, ptrace_faultinfo is smaller!
136 ret = copy_to_user(p, &child->thread.arch.faultinfo,
137 sizeof(struct ptrace_faultinfo));
143 struct ptrace_ldt ldt;
145 if (copy_from_user(&ldt, p, sizeof(ldt))) {
151 * This one is confusing, so just punt and return -EIO for
158 #ifdef PTRACE_ARCH_PRCTL
159 case PTRACE_ARCH_PRCTL:
160 /* XXX Calls ptrace on the host - needs some SMP thinking */
161 ret = arch_prctl(child, data, (void *) addr);
165 ret = ptrace_request(child, request, addr, data);
167 ret = subarch_ptrace(child, request, addr, data);
174 static void send_sigtrap(struct task_struct *tsk, struct uml_pt_regs *regs,
179 memset(&info, 0, sizeof(info));
180 info.si_signo = SIGTRAP;
181 info.si_code = TRAP_BRKPT;
184 info.si_addr = UPT_IS_USER(regs) ? (void __user *) UPT_IP(regs) : NULL;
186 /* Send us the fake SIGTRAP */
187 force_sig_info(SIGTRAP, &info, tsk);
191 * XXX Check PT_DTRACE vs TIF_SINGLESTEP for singlestepping check and
192 * PT_PTRACED vs TIF_SYSCALL_TRACE for syscall tracing check
194 void syscall_trace(struct uml_pt_regs *regs, int entryexit)
196 int is_singlestep = (current->ptrace & PT_DTRACE) && entryexit;
199 if (unlikely(current->audit_context)) {
201 audit_syscall_entry(HOST_AUDIT_ARCH,
202 UPT_SYSCALL_NR(regs),
203 UPT_SYSCALL_ARG1(regs),
204 UPT_SYSCALL_ARG2(regs),
205 UPT_SYSCALL_ARG3(regs),
206 UPT_SYSCALL_ARG4(regs));
207 else audit_syscall_exit(AUDITSC_RESULT(UPT_SYSCALL_RET(regs)),
208 UPT_SYSCALL_RET(regs));
211 /* Fake a debug trap */
213 send_sigtrap(current, regs, 0);
215 if (!test_thread_flag(TIF_SYSCALL_TRACE))
218 if (!(current->ptrace & PT_PTRACED))
222 * the 0x80 provides a way for the tracing parent to distinguish
223 * between a syscall stop and SIGTRAP delivery
225 tracesysgood = (current->ptrace & PT_TRACESYSGOOD);
226 ptrace_notify(SIGTRAP | (tracesysgood ? 0x80 : 0));
228 if (entryexit) /* force do_signal() --> is_syscall() */
229 set_thread_flag(TIF_SIGPENDING);
232 * this isn't the same as continuing with a signal, but it will do
233 * for normal use. strace only continues with a signal if the
234 * stopping signal is not SIGTRAP. -brl
236 if (current->exit_code) {
237 send_sig(current->exit_code, current, 1);
238 current->exit_code = 0;