blackfin: check __get_user() return value
authorAl Viro <viro@zeniv.linux.org.uk>
Thu, 3 May 2012 01:14:30 +0000 (21:14 -0400)
committerAl Viro <viro@zeniv.linux.org.uk>
Fri, 1 Jun 2012 17:01:27 +0000 (13:01 -0400)
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
arch/blackfin/kernel/signal.c

index 35459e6..6682b73 100644 (file)
@@ -187,17 +187,22 @@ setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t * info,
        err |= copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set));
 
        if (err)
-               goto give_sigsegv;
+               return -EFAULT;
 
        /* Set up registers for signal handler */
-       wrusp((unsigned long)frame);
        if (current->personality & FDPIC_FUNCPTRS) {
                struct fdpic_func_descriptor __user *funcptr =
                        (struct fdpic_func_descriptor *) ka->sa.sa_handler;
-               __get_user(regs->pc, &funcptr->text);
-               __get_user(regs->p3, &funcptr->GOT);
+               u32 pc, p3;
+               err |= __get_user(pc, &funcptr->text);
+               err |= __get_user(p3, &funcptr->GOT);
+               if (err)
+                       return -EFAULT;
+               regs->pc = pc;
+               regs->p3 = p3;
        } else
                regs->pc = (unsigned long)ka->sa.sa_handler;
+       wrusp((unsigned long)frame);
        regs->rets = SIGRETURN_STUB;
 
        regs->r0 = frame->sig;
@@ -205,10 +210,6 @@ setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t * info,
        regs->r2 = (unsigned long)(&frame->uc);
 
        return 0;
-
- give_sigsegv:
-       force_sigsegv(sig, current);
-       return -EFAULT;
 }
 
 static inline void
@@ -248,20 +249,17 @@ static void
 handle_signal(int sig, siginfo_t *info, struct k_sigaction *ka,
              struct pt_regs *regs)
 {
-       int ret;
-
        /* are we from a system call? to see pt_regs->orig_p0 */
        if (regs->orig_p0 >= 0)
                /* If so, check system call restarting.. */
                handle_restart(regs, ka, 1);
 
        /* set up the stack frame */
-       ret = setup_rt_frame(sig, ka, info, sigmask_to_save(), regs);
-       if (ret)
-               return;
-
-       signal_delivered(sig, info, ka, regs,
-                       test_thread_flag(TIF_SINGLESTEP));
+       if (setup_rt_frame(sig, ka, info, sigmask_to_save(), regs) < 0)
+               force_sigsegv(sig, current);
+       else 
+               signal_delivered(sig, info, ka, regs,
+                               test_thread_flag(TIF_SINGLESTEP));
 }
 
 /*