ptrace: generic PTRACE_SINGLEBLOCK

[safe/jmp/linux-2.6] / kernel / ptrace.c

diff --git a/kernel/ptrace.c b/kernel/ptrace.c
index 0c65d30..973d727 100644 (file)
--- a/kernel/ptrace.c
+++ b/kernel/ptrace.c
@@ -196,7 +196,7 @@ repeat:
        /* the same process cannot be attached many times */
        if (task->ptrace & PT_PTRACED)
                goto bad;
-       retval = may_attach(task);
+       retval = __ptrace_may_attach(task);
        if (retval)
                goto bad;
 
@@ -366,6 +366,60 @@ static int ptrace_setsiginfo(struct task_struct *child, siginfo_t __user * data)
        return error;
 }
 
+
+#ifdef PTRACE_SINGLESTEP
+#define is_singlestep(request)         ((request) == PTRACE_SINGLESTEP)
+#else
+#define is_singlestep(request)         0
+#endif
+
+#ifdef PTRACE_SINGLEBLOCK
+#define is_singleblock(request)                ((request) == PTRACE_SINGLEBLOCK)
+#else
+#define is_singleblock(request)                0
+#endif
+
+#ifdef PTRACE_SYSEMU
+#define is_sysemu_singlestep(request)  ((request) == PTRACE_SYSEMU_SINGLESTEP)
+#else
+#define is_sysemu_singlestep(request)  0
+#endif
+
+static int ptrace_resume(struct task_struct *child, long request, long data)
+{
+       if (!valid_signal(data))
+               return -EIO;
+
+       if (request == PTRACE_SYSCALL)
+               set_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
+       else
+               clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
+
+#ifdef TIF_SYSCALL_EMU
+       if (request == PTRACE_SYSEMU || request == PTRACE_SYSEMU_SINGLESTEP)
+               set_tsk_thread_flag(child, TIF_SYSCALL_EMU);
+       else
+               clear_tsk_thread_flag(child, TIF_SYSCALL_EMU);
+#endif
+
+       if (is_singleblock(request)) {
+               if (unlikely(!arch_has_block_step()))
+                       return -EIO;
+               user_enable_block_step(child);
+       } else if (is_singlestep(request) || is_sysemu_singlestep(request)) {
+               if (unlikely(!arch_has_single_step()))
+                       return -EIO;
+               user_enable_single_step(child);
+       }
+       else
+               user_disable_single_step(child);
+
+       child->exit_code = data;
+       wake_up_process(child);
+
+       return 0;
+}
+
 int ptrace_request(struct task_struct *child, long request,
                   long addr, long data)
 {
@@ -390,6 +444,26 @@ int ptrace_request(struct task_struct *child, long request,
        case PTRACE_DETACH:      /* detach a process that was attached. */
                ret = ptrace_detach(child, data);
                break;
+
+#ifdef PTRACE_SINGLESTEP
+       case PTRACE_SINGLESTEP:
+#endif
+#ifdef PTRACE_SINGLEBLOCK
+       case PTRACE_SINGLEBLOCK:
+#endif
+#ifdef PTRACE_SYSEMU
+       case PTRACE_SYSEMU:
+       case PTRACE_SYSEMU_SINGLESTEP:
+#endif
+       case PTRACE_SYSCALL:
+       case PTRACE_CONT:
+               return ptrace_resume(child, request, data);
+
+       case PTRACE_KILL:
+               if (child->exit_state)  /* already dead */
+                       return 0;
+               return ptrace_resume(child, request, SIGKILL);
+
        default:
                break;
        }
@@ -470,6 +544,8 @@ asmlinkage long sys_ptrace(long request, long pid, long addr, long data)
        lock_kernel();
        if (request == PTRACE_TRACEME) {
                ret = ptrace_traceme();
+               if (!ret)
+                       arch_ptrace_attach(current);
                goto out;
        }