Merge branch 'task_killable' of git://git.kernel.org/pub/scm/linux/kernel/git/willy...

[pandora-kernel.git] / kernel / ptrace.c

diff --git a/kernel/ptrace.c b/kernel/ptrace.c
index 26f9923..b0d4ab4 100644 (file)
--- a/kernel/ptrace.c
+++ b/kernel/ptrace.c
@@ -120,7 +120,7 @@ int ptrace_check_attach(struct task_struct *child, int kill)
        return ret;
 }
 
-static int may_attach(struct task_struct *task)
+int __ptrace_may_attach(struct task_struct *task)
 {
        /* May we inspect the given task?
         * This check is used both for attaching with ptrace
@@ -154,7 +154,7 @@ int ptrace_may_attach(struct task_struct *task)
 {
        int err;
        task_lock(task);
-       err = may_attach(task);
+       err = __ptrace_may_attach(task);
        task_unlock(task);
        return !err;
 }
@@ -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;
 
@@ -366,12 +366,73 @@ 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)
 {
        int ret = -EIO;
 
        switch (request) {
+       case PTRACE_PEEKTEXT:
+       case PTRACE_PEEKDATA:
+               return generic_ptrace_peekdata(child, addr, data);
+       case PTRACE_POKETEXT:
+       case PTRACE_POKEDATA:
+               return generic_ptrace_pokedata(child, addr, data);
+
 #ifdef PTRACE_OLDSETOPTIONS
        case PTRACE_OLDSETOPTIONS:
 #endif
@@ -390,6 +451,26 @@ 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 +551,8 @@ 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;
        }
 
@@ -524,3 +607,87 @@ int generic_ptrace_pokedata(struct task_struct *tsk, long addr, long data)
        copied = access_process_vm(tsk, addr, &data, sizeof(data), 1);
        return (copied == sizeof(data)) ? 0 : -EIO;
 }
+
+#ifdef CONFIG_COMPAT
+#include <linux/compat.h>
+
+int compat_ptrace_request(struct task_struct *child, compat_long_t request,
+                         compat_ulong_t addr, compat_ulong_t data)
+{
+       compat_ulong_t __user *datap = compat_ptr(data);
+       compat_ulong_t word;
+       int ret;
+
+       switch (request) {
+       case PTRACE_PEEKTEXT:
+       case PTRACE_PEEKDATA:
+               ret = access_process_vm(child, addr, &word, sizeof(word), 0);
+               if (ret != sizeof(word))
+                       ret = -EIO;
+               else
+                       ret = put_user(word, datap);
+               break;
+
+       case PTRACE_POKETEXT:
+       case PTRACE_POKEDATA:
+               ret = access_process_vm(child, addr, &data, sizeof(data), 1);
+               ret = (ret != sizeof(data) ? -EIO : 0);
+               break;
+
+       case PTRACE_GETEVENTMSG:
+               ret = put_user((compat_ulong_t) child->ptrace_message, datap);
+               break;
+
+       default:
+               ret = ptrace_request(child, request, addr, data);
+       }
+
+       return ret;
+}
+
+#ifdef __ARCH_WANT_COMPAT_SYS_PTRACE
+asmlinkage long compat_sys_ptrace(compat_long_t request, compat_long_t pid,
+                                 compat_long_t addr, compat_long_t data)
+{
+       struct task_struct *child;
+       long ret;
+
+       /*
+        * This lock_kernel fixes a subtle race with suid exec
+        */
+       lock_kernel();
+       if (request == PTRACE_TRACEME) {
+               ret = ptrace_traceme();
+               goto out;
+       }
+
+       child = ptrace_get_task_struct(pid);
+       if (IS_ERR(child)) {
+               ret = PTR_ERR(child);
+               goto out;
+       }
+
+       if (request == PTRACE_ATTACH) {
+               ret = ptrace_attach(child);
+               /*
+                * Some architectures need to do book-keeping after
+                * a ptrace attach.
+                */
+               if (!ret)
+                       arch_ptrace_attach(child);
+               goto out_put_task_struct;
+       }
+
+       ret = ptrace_check_attach(child, request == PTRACE_KILL);
+       if (!ret)
+               ret = compat_arch_ptrace(child, request, addr, data);
+
+ out_put_task_struct:
+       put_task_struct(child);
+ out:
+       unlock_kernel();
+       return ret;
+}
+#endif /* __ARCH_WANT_COMPAT_SYS_PTRACE */
+
+#endif /* CONFIG_COMPAT */