commit 9d7a9c3a8de8626c497db3a23226e7965ea2988e
author zhanglimin <zhanglimin@loongson.cn> Thu May 25 19:59:39 2023 -0700
committer Copybara-Service <copybara-worker@google.com> Thu May 25 20:26:04 2023 -0700
tree 1adc1d49838cf98dfae6b6f8db961791b722c9e3
parent 0c3224853b71a5ce42073d0012f2e7e9fe402a02

[fuzzer] Don't hard-code page size in FuzzerUtil.h

Don't hard code the page in FuzzerUtil.h, this breaks on
e.g. LoongArch which defaults to a 16KiB page size.

Reviewed By: #sanitizers, vitalybuka

Differential Revision: https://reviews.llvm.org/D140607

GitOrigin-RevId: baa1488c169391deb6cc7d6a29ba7f40d0a2086f

lib/fuzzer/FuzzerUtil.cpp

diff --git a/lib/fuzzer/FuzzerUtil.cpp b/lib/fuzzer/FuzzerUtil.cpp
index aeab70f..71c3dc1 100644
--- a/lib/fuzzer/FuzzerUtil.cpp
+++ b/lib/fuzzer/FuzzerUtil.cpp
@@ -21,6 +21,7 @@
 #include <stdio.h>
 #include <sys/types.h>
 #include <thread>
+#include <unistd.h>
 
 namespace fuzzer {
 
@@ -234,4 +235,9 @@
   return Res;
 }
 
+size_t PageSize() {
+  static size_t PageSizeCached = sysconf(_SC_PAGESIZE);
+  return PageSizeCached;
+}
+
 }  // namespace fuzzer

lib/fuzzer/FuzzerUtil.h

diff --git a/lib/fuzzer/FuzzerUtil.h b/lib/fuzzer/FuzzerUtil.h
index 71d4909..5296e77 100644
--- a/lib/fuzzer/FuzzerUtil.h
+++ b/lib/fuzzer/FuzzerUtil.h
@@ -94,7 +94,8 @@
   return static_cast<size_t>((sizeof(unsigned long long) * 8) - Clzll(X) - 1);
 }
 
-inline size_t PageSize() { return 4096; }
+size_t PageSize();
+
 inline uint8_t *RoundUpByPage(uint8_t *P) {
   uintptr_t X = reinterpret_cast<uintptr_t>(P);
   size_t Mask = PageSize() - 1;