Fix corner case in cpuinfo parser.

I realized looking at the sigalgs parser that I messed up the
space-splitting logic slightly. If the CPU features are "foo bar baz",
it would not parse "baz". This doesn't particular matter (the last one
is "crc32"), but better to parse it correctly.

Fix this and add a unit test. While I'm here, may as well add a fuzzer
too.

Change-Id: Ifc1603b8f70d975f391d10e51ede95deec31a83d
Reviewed-on: https://boringssl-review.googlesource.com/31464
Commit-Queue: David Benjamin <davidben@google.com>
CQ-Verified: CQ bot account: commit-bot@chromium.org <commit-bot@chromium.org>
Reviewed-by: Adam Langley <agl@google.com>

1 files changed, 24 insertions, 0 deletions

diff --git a/fuzz/arm_cpuinfo.cc b/fuzz/arm_cpuinfo.cc
new file mode 100644
index 0000000..5d70046
--- /dev/null
+++ b/fuzz/arm_cpuinfo.cc
@@ -0,0 +1,24 @@
+/* Copyright (c) 2018, Google Inc.
+ *
+ * Permission to use, copy, modify, and/or distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
+ * SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION
+ * OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
+ * CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. */
+
+#include "../crypto/cpu-arm-linux.h"
+
+
+extern "C" int LLVMFuzzerTestOneInput(const uint8_t *buf, size_t len) {
+  STRING_PIECE sp = {reinterpret_cast<const char *>(buf), len};
+  crypto_get_arm_hwcap_from_cpuinfo(&sp);
+  crypto_get_arm_hwcap2_from_cpuinfo(&sp);
+  crypto_cpuinfo_has_broken_neon(&sp);
+  return 0;
+}