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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
commit57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch)
tree5e910f0e82173f4ef4f51111366a3f1299037a7b /arch/um/kernel/ptrace.c
Initial import
Diffstat (limited to 'arch/um/kernel/ptrace.c')
-rw-r--r--arch/um/kernel/ptrace.c165
1 files changed, 165 insertions, 0 deletions
diff --git a/arch/um/kernel/ptrace.c b/arch/um/kernel/ptrace.c
new file mode 100644
index 000000000..174ee5017
--- /dev/null
+++ b/arch/um/kernel/ptrace.c
@@ -0,0 +1,165 @@
+/*
+ * Copyright (C) 2000 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
+ * Licensed under the GPL
+ */
+
+#include <linux/audit.h>
+#include <linux/ptrace.h>
+#include <linux/sched.h>
+#include <linux/tracehook.h>
+#include <asm/uaccess.h>
+
+void user_enable_single_step(struct task_struct *child)
+{
+ child->ptrace |= PT_DTRACE;
+ child->thread.singlestep_syscall = 0;
+
+#ifdef SUBARCH_SET_SINGLESTEPPING
+ SUBARCH_SET_SINGLESTEPPING(child, 1);
+#endif
+}
+
+void user_disable_single_step(struct task_struct *child)
+{
+ child->ptrace &= ~PT_DTRACE;
+ child->thread.singlestep_syscall = 0;
+
+#ifdef SUBARCH_SET_SINGLESTEPPING
+ SUBARCH_SET_SINGLESTEPPING(child, 0);
+#endif
+}
+
+/*
+ * Called by kernel/ptrace.c when detaching..
+ */
+void ptrace_disable(struct task_struct *child)
+{
+ user_disable_single_step(child);
+}
+
+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 arch_ptrace(struct task_struct *child, long request,
+ unsigned long addr, unsigned long data)
+{
+ int i, ret;
+ unsigned long __user *p = (void __user *)data;
+ void __user *vp = p;
+
+ switch (request) {
+ /* read the word at location addr in the USER area. */
+ case PTRACE_PEEKUSR:
+ ret = peek_user(child, addr, data);
+ break;
+
+ /* write the word at location addr in the USER area */
+ case PTRACE_POKEUSR:
+ ret = poke_user(child, addr, data);
+ break;
+
+ case PTRACE_SYSEMU:
+ case PTRACE_SYSEMU_SINGLESTEP:
+ ret = -EIO;
+ break;
+
+#ifdef PTRACE_GETREGS
+ case PTRACE_GETREGS: { /* Get all gp regs from the child. */
+ if (!access_ok(VERIFY_WRITE, p, MAX_REG_OFFSET)) {
+ ret = -EIO;
+ break;
+ }
+ for ( i = 0; i < MAX_REG_OFFSET; i += sizeof(long) ) {
+ __put_user(getreg(child, i), p);
+ p++;
+ }
+ 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, p, MAX_REG_OFFSET)) {
+ ret = -EIO;
+ break;
+ }
+ for ( i = 0; i < MAX_REG_OFFSET; i += sizeof(long) ) {
+ __get_user(tmp, p);
+ putreg(child, i, tmp);
+ p++;
+ }
+ ret = 0;
+ break;
+ }
+#endif
+ case PTRACE_GET_THREAD_AREA:
+ ret = ptrace_get_thread_area(child, addr, vp);
+ break;
+
+ case PTRACE_SET_THREAD_AREA:
+ ret = ptrace_set_thread_area(child, addr, vp);
+ break;
+
+ default:
+ ret = ptrace_request(child, request, addr, data);
+ if (ret == -EIO)
+ ret = subarch_ptrace(child, request, addr, data);
+ break;
+ }
+
+ return ret;
+}
+
+static void send_sigtrap(struct task_struct *tsk, struct 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 fake 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_enter(struct pt_regs *regs)
+{
+ audit_syscall_entry(UPT_SYSCALL_NR(&regs->regs),
+ UPT_SYSCALL_ARG1(&regs->regs),
+ UPT_SYSCALL_ARG2(&regs->regs),
+ UPT_SYSCALL_ARG3(&regs->regs),
+ UPT_SYSCALL_ARG4(&regs->regs));
+
+ if (!test_thread_flag(TIF_SYSCALL_TRACE))
+ return;
+
+ tracehook_report_syscall_entry(regs);
+}
+
+void syscall_trace_leave(struct pt_regs *regs)
+{
+ int ptraced = current->ptrace;
+
+ audit_syscall_exit(regs);
+
+ /* Fake a debug trap */
+ if (ptraced & PT_DTRACE)
+ send_sigtrap(current, &regs->regs, 0);
+
+ if (!test_thread_flag(TIF_SYSCALL_TRACE))
+ return;
+
+ tracehook_report_syscall_exit(regs, 0);
+ /* force do_signal() --> is_syscall() */
+ if (ptraced & PT_PTRACED)
+ set_thread_flag(TIF_SIGPENDING);
+}