Fortify poll and ppoll.

And remove the test for FD_ZERO fortification, which never made much
sense anyway.

Change-Id: Id1009c5298d461fa4722189e8ecaf22f0c529536
diff --git a/libc/bionic/__poll_chk.cpp b/libc/bionic/__poll_chk.cpp
new file mode 100644
index 0000000..3acac4e
--- /dev/null
+++ b/libc/bionic/__poll_chk.cpp
@@ -0,0 +1,49 @@
+/*
+ * Copyright (C) 2015 The Android Open Source Project
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *  * Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *  * Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#undef _FORTIFY_SOURCE
+#include <poll.h>
+#include "private/libc_logging.h"
+
+#include <stdio.h>
+
+extern "C" int __poll_chk(struct pollfd* fds, nfds_t fd_count, int timeout, size_t fds_size) {
+fprintf(stderr, "__poll_chk %p %i %i %i\n", fds, (int)fd_count, timeout, (int) fds_size);
+  if (__predict_false(fds_size / sizeof(*fds) < fd_count)) {
+    __fortify_chk_fail("poll: pollfd array smaller than fd count", 0);
+  }
+  return poll(fds, fd_count, timeout);
+}
+
+extern "C" int __ppoll_chk(struct pollfd* fds, nfds_t fd_count, const struct timespec* timeout, const sigset_t* mask, size_t fds_size) {
+fprintf(stderr, "__ppoll_chk %p %i %p %p %i\n", fds, (int)fd_count, timeout, mask, (int) fds_size);
+  if (__predict_false(fds_size / sizeof(*fds) < fd_count)) {
+    __fortify_chk_fail("ppoll: pollfd array smaller than fd count", 0);
+  }
+  return ppoll(fds, fd_count, timeout, mask);
+}