1 files changed, 15 insertions, 18 deletions

diff --git a/kernel/signal.c b/kernel/signal.c
index 7aaa51d8e5b8..3d09cf6cde75 100644
--- a/kernel/signal.c
+++ b/kernel/signal.c
@@ -680,23 +680,17 @@ int dequeue_signal(struct task_struct *tsk, sigset_t *mask, siginfo_t *info)
  * No need to set need_resched since signal event passing
  * goes through ->blocked
  */
-void signal_wake_up(struct task_struct *t, int resume)
+void signal_wake_up_state(struct task_struct *t, unsigned int state)
 {
-        unsigned int mask;
-
         set_tsk_thread_flag(t, TIF_SIGPENDING);
-
         /*
-         * For SIGKILL, we want to wake it up in the stopped/traced/killable
+         * TASK_WAKEKILL also means wake it up in the stopped/traced/killable
          * case. We don't check t->state here because there is a race with it
          * executing another processor and just now entering stopped state.
          * By using wake_up_state, we ensure the process will wake up and
          * handle its death signal.
          */
-        mask = TASK_INTERRUPTIBLE;
-        if (resume)
-                mask |= TASK_WAKEKILL;
-        if (!wake_up_state(t, mask))
+        if (!wake_up_state(t, state | TASK_INTERRUPTIBLE))
                 kick_process(t);
 }
 
@@ -844,7 +838,7 @@ static void ptrace_trap_notify(struct task_struct *t)
         assert_spin_locked(&t->sighand->siglock);
 
         task_set_jobctl_pending(t, JOBCTL_TRAP_NOTIFY);
-        signal_wake_up(t, t->jobctl & JOBCTL_LISTENING);
+        ptrace_signal_wake_up(t, t->jobctl & JOBCTL_LISTENING);
 }
 
 /*
@@ -1800,6 +1794,10 @@ static inline int may_ptrace_stop(void)
          * If SIGKILL was already sent before the caller unlocked
          * ->siglock we must see ->core_state != NULL. Otherwise it
          * is safe to enter schedule().
+         *
+         * This is almost outdated, a task with the pending SIGKILL can't
+         * block in TASK_TRACED. But PTRACE_EVENT_EXIT can be reported
+         * after SIGKILL was already dequeued.
          */
         if (unlikely(current->mm->core_state) &&
             unlikely(current->mm == current->parent->mm))
@@ -1925,6 +1923,7 @@ static void ptrace_stop(int exit_code, int why, int clear_code, siginfo_t *info)
                 if (gstop_done)
                         do_notify_parent_cldstop(current, false, why);
 
+                /* tasklist protects us from ptrace_freeze_traced() */
                 __set_current_state(TASK_RUNNING);
                 if (clear_code)
                         current->exit_code = 0;
@@ -2528,11 +2527,8 @@ static void __set_task_blocked(struct task_struct *tsk, const sigset_t *newset)
  */
 void set_current_blocked(sigset_t *newset)
 {
-        struct task_struct *tsk = current;
         sigdelsetmask(newset, sigmask(SIGKILL) | sigmask(SIGSTOP));
-        spin_lock_irq(&tsk->sighand->siglock);
-        __set_task_blocked(tsk, newset);
-        spin_unlock_irq(&tsk->sighand->siglock);
+        __set_current_blocked(newset);
 }
 
 void __set_current_blocked(const sigset_t *newset)
@@ -3119,8 +3115,9 @@ int __save_altstack(stack_t __user *uss, unsigned long sp)
 
 #ifdef CONFIG_COMPAT
 #ifdef CONFIG_GENERIC_SIGALTSTACK
-asmlinkage long compat_sys_sigaltstack(const compat_stack_t __user *uss_ptr,
-                                       compat_stack_t __user *uoss_ptr)
+COMPAT_SYSCALL_DEFINE2(sigaltstack,
+                        const compat_stack_t __user *, uss_ptr,
+                        compat_stack_t __user *, uoss_ptr)
 {
         stack_t uss, uoss;
         int ret;
@@ -3204,7 +3201,6 @@ SYSCALL_DEFINE3(sigprocmask, int, how, old_sigset_t __user *, nset,
         if (nset) {
                 if (copy_from_user(&new_set, nset, sizeof(*nset)))
                         return -EFAULT;
-                new_set &= ~(sigmask(SIGKILL) | sigmask(SIGSTOP));
 
                 new_blocked = current->blocked;
 
@@ -3222,7 +3218,7 @@ SYSCALL_DEFINE3(sigprocmask, int, how, old_sigset_t __user *, nset,
                         return -EINVAL;
                 }
 
-                __set_current_blocked(&new_blocked);
+                set_current_blocked(&new_blocked);
         }
 
         if (oset) {
@@ -3286,6 +3282,7 @@ SYSCALL_DEFINE1(ssetmask, int, newmask)
         int old = current->blocked.sig[0];
         sigset_t newset;
 
+        siginitset(&newset, newmask);
         set_current_blocked(&newset);
 
         return old;