commit c72dad9f764186d82715899cee477b3a296fb918
author Hui Yingst <nigi@chromium.org> Mon May 22 21:02:36 2023 +0000
committer Pdfium LUCI CQ <pdfium-scoped@luci-project-accounts.iam.gserviceaccount.com> Mon May 22 21:02:36 2023 +0000
tree eeb6a6deae79c396336c23e4ed3645e6e47d45f5
parent 328edf32ad22f3383d02514916ddf0a1617fc32b

Avoid setting DiscardableMemoryAllocator in `LLVMFuzzerTestOneInput()`

If compiled with chromium, a DiscardableMemoryAllocator is already
set by `LLVMFuzzerInitialize()` in chromium before calling
`LLVMFuzzerTestOneInput()` when running `pdfium_fuzzer`, which causes
DCHECK failure in DiscardableMemoryAllocator::SetInstance() since the
allocator is already set.

This CL removes the steps of setting up DiscardableMemoryAllocator in
`LLVMFuzzerTestOneInput()` to avoid the DCHECK failure. And it
simplifies the fuzzer process to only set up the
DiscardableMemoryAllocator once.

Bug: chromium:1440491
Change-Id: I48e678253dacd696bd0fbf01805e150d9026ac53
Reviewed-on: https://pdfium-review.googlesource.com/c/pdfium/+/107890
Commit-Queue: Nigi <nigi@chromium.org>
Reviewed-by: Lei Zhang <thestig@chromium.org>

testing/fuzzers/BUILD.gn

diff --git a/testing/fuzzers/BUILD.gn b/testing/fuzzers/BUILD.gn
index 35624cb..698987f 100644
--- a/testing/fuzzers/BUILD.gn
+++ b/testing/fuzzers/BUILD.gn
@@ -2,7 +2,6 @@
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
-import("//build_overrides/build.gni")
 import("../../pdfium.gni")
 
 config("fuzzer_config") {
@@ -247,9 +246,6 @@
     if (is_public && pdf_enable_xfa) {
       deps += [ ":fuzzer_xfa_process_state" ]
     }
-    if (build_with_chromium) {
-      defines += [ "BUILD_WITH_CHROMIUM" ]
-    }
   }
 }
 
@@ -620,11 +616,5 @@
 pdfium_fuzzer("pdfium_fuzzer") {
   sources = [ "pdfium_fuzzer.cc" ]
   deps = [ ":fuzzer_helper" ]
-  if (build_with_chromium) {
-    deps += [
-      "//base",
-      "//base/test:test_support",
-    ]
-  }
   public_fuzzer = true
 }

testing/fuzzers/DEPS

diff --git a/testing/fuzzers/DEPS b/testing/fuzzers/DEPS
index d577044..fe9eaf6 100644
--- a/testing/fuzzers/DEPS
+++ b/testing/fuzzers/DEPS
@@ -1,7 +1,4 @@
 include_rules = [
   '+fxbarcode',
   '+xfa',
-
-  # Only used when the fuzzer is embedded in Chromium.
-  '+base',
 ]

testing/fuzzers/pdfium_fuzzer.cc

diff --git a/testing/fuzzers/pdfium_fuzzer.cc b/testing/fuzzers/pdfium_fuzzer.cc
index 7e25fed..e70702a 100644
--- a/testing/fuzzers/pdfium_fuzzer.cc
+++ b/testing/fuzzers/pdfium_fuzzer.cc
@@ -6,12 +6,6 @@
 
 #include "testing/fuzzers/pdfium_fuzzer_helper.h"
 
-#if defined(BUILD_WITH_CHROMIUM)
-#include "base/memory/discardable_memory_allocator.h"
-#include "base/no_destructor.h"
-#include "base/test/test_discardable_memory_allocator.h"
-#endif
-
 class PDFiumFuzzer : public PDFiumFuzzerHelper {
  public:
   PDFiumFuzzer() = default;
@@ -21,12 +15,6 @@
 };
 
 extern "C" int LLVMFuzzerTestOneInput(const uint8_t* data, size_t size) {
-#if defined(BUILD_WITH_CHROMIUM)
-  static base::NoDestructor<base::TestDiscardableMemoryAllocator>
-      test_memory_allocator;
-  base::DiscardableMemoryAllocator::SetInstance(test_memory_allocator.get());
-#endif
-
   PDFiumFuzzer fuzzer;
   fuzzer.RenderPdf(reinterpret_cast<const char*>(data), size);
   return 0;