1 files changed, 20 insertions, 17 deletions

diff --git a/kernel/signal.c b/kernel/signal.c
index d81f4952eebb..64c5deeaca5d 100644
--- a/kernel/signal.c
+++ b/kernel/signal.c
@@ -1410,7 +1410,7 @@ int do_notify_parent(struct task_struct *tsk, int sig)
         /* do_notify_parent_cldstop should have been called instead.  */
         BUG_ON(task_is_stopped_or_traced(tsk));
 
-        BUG_ON(!tsk->ptrace &&
+        BUG_ON(!task_ptrace(tsk) &&
                (tsk->group_leader != tsk || !thread_group_empty(tsk)));
 
         info.si_signo = sig;
@@ -1449,7 +1449,7 @@ int do_notify_parent(struct task_struct *tsk, int sig)
 
         psig = tsk->parent->sighand;
         spin_lock_irqsave(&psig->siglock, flags);
-        if (!tsk->ptrace && sig == SIGCHLD &&
+        if (!task_ptrace(tsk) && sig == SIGCHLD &&
             (psig->action[SIGCHLD-1].sa.sa_handler == SIG_IGN ||
              (psig->action[SIGCHLD-1].sa.sa_flags & SA_NOCLDWAIT))) {
                 /*
@@ -1486,7 +1486,7 @@ static void do_notify_parent_cldstop(struct task_struct *tsk, int why)
         struct task_struct *parent;
         struct sighand_struct *sighand;
 
-        if (tsk->ptrace & PT_PTRACED)
+        if (task_ptrace(tsk))
                 parent = tsk->parent;
         else {
                 tsk = tsk->group_leader;
@@ -1499,7 +1499,7 @@ static void do_notify_parent_cldstop(struct task_struct *tsk, int why)
          * see comment in do_notify_parent() abot the following 3 lines
          */
         rcu_read_lock();
-        info.si_pid = task_pid_nr_ns(tsk, tsk->parent->nsproxy->pid_ns);
+        info.si_pid = task_pid_nr_ns(tsk, parent->nsproxy->pid_ns);
         info.si_uid = __task_cred(tsk)->uid;
         rcu_read_unlock();
 
@@ -1535,7 +1535,7 @@ static void do_notify_parent_cldstop(struct task_struct *tsk, int why)
 
 static inline int may_ptrace_stop(void)
 {
-        if (!likely(current->ptrace & PT_PTRACED))
+        if (!likely(task_ptrace(current)))
                 return 0;
         /*
          * Are we in the middle of do_coredump?
@@ -1753,7 +1753,7 @@ static int do_signal_stop(int signr)
 static int ptrace_signal(int signr, siginfo_t *info,
                          struct pt_regs *regs, void *cookie)
 {
-        if (!(current->ptrace & PT_PTRACED))
+        if (!task_ptrace(current))
                 return signr;
 
         ptrace_signal_deliver(regs, cookie);
@@ -2454,11 +2454,9 @@ do_sigaltstack (const stack_t __user *uss, stack_t __user *uoss, unsigned long s
         stack_t oss;
         int error;
 
-        if (uoss) {
-                oss.ss_sp = (void __user *) current->sas_ss_sp;
-                oss.ss_size = current->sas_ss_size;
-                oss.ss_flags = sas_ss_flags(sp);
-        }
+        oss.ss_sp = (void __user *) current->sas_ss_sp;
+        oss.ss_size = current->sas_ss_size;
+        oss.ss_flags = sas_ss_flags(sp);
 
         if (uss) {
                 void __user *ss_sp;
@@ -2466,10 +2464,12 @@ do_sigaltstack (const stack_t __user *uss, stack_t __user *uoss, unsigned long s
                 int ss_flags;
 
                 error = -EFAULT;
-                if (!access_ok(VERIFY_READ, uss, sizeof(*uss))
-                    || __get_user(ss_sp, &uss->ss_sp)
-                    || __get_user(ss_flags, &uss->ss_flags)
-                    || __get_user(ss_size, &uss->ss_size))
+                if (!access_ok(VERIFY_READ, uss, sizeof(*uss)))
+                        goto out;
+                error = __get_user(ss_sp, &uss->ss_sp) |
+                        __get_user(ss_flags, &uss->ss_flags) |
+                        __get_user(ss_size, &uss->ss_size);
+                if (error)
                         goto out;
 
                 error = -EPERM;
@@ -2501,13 +2501,16 @@ do_sigaltstack (const stack_t __user *uss, stack_t __user *uoss, unsigned long s
                 current->sas_ss_size = ss_size;
         }
 
+        error = 0;
         if (uoss) {
                 error = -EFAULT;
-                if (copy_to_user(uoss, &oss, sizeof(oss)))
+                if (!access_ok(VERIFY_WRITE, uoss, sizeof(*uoss)))
                         goto out;
+                error = __put_user(oss.ss_sp, &uoss->ss_sp) |
+                        __put_user(oss.ss_size, &uoss->ss_size) |
+                        __put_user(oss.ss_flags, &uoss->ss_flags);
         }
 
-        error = 0;
 out:
         return error;
 }