s390/ptrace: fix PTRACE_GET_LAST_BREAK error handling

Return -EFAULT if put_user() for the PTRACE_GET_LAST_BREAK
request fails, instead of silently ignoring it.
Reviewed-by: Sven Schnelle <svens@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>

arch/s390/kernel/ptrace.c

@@ -474,9 +474,7 @@ long arch_ptrace(struct task_struct *child, long request,
 		}
 		return 0;
 	case PTRACE_GET_LAST_BREAK:
-		put_user(child->thread.last_break,
-			 (unsigned long __user *) data);
-		return 0;
+		return put_user(child->thread.last_break, (unsigned long __user *)data);
 	case PTRACE_ENABLE_TE:
 		if (!MACHINE_HAS_TE)
 			return -EIO;
@@ -824,9 +822,7 @@ long compat_arch_ptrace(struct task_struct *child, compat_long_t request,
 		}
 		return 0;
 	case PTRACE_GET_LAST_BREAK:
-		put_user(child->thread.last_break,
-			 (unsigned int __user *) data);
-		return 0;
+		return put_user(child->thread.last_break, (unsigned int __user *)data);
 	}
 	return compat_ptrace_request(child, request, addr, data);
 }