undefect. CWE-407 — 63 sites patched across 27 ecosystems

Authors: russell@unturf.com · brackishbert@gmail.com · foxhop.net · TimeHexOn.com Patches, unit tests, benchmarks, whitepaper, and outreach briefs. Public domain — no copyright claimed. Use freely.
2026-03-26 17:11:57 -04:00 · 2026-03-26 17:11:57 -04:00 · 0a580b313d
commit 0a580b313d
70422 changed files with 17213626 additions and 0 deletions
--- a/test/hotspot/gtest/runtime/test_os_linux.cpp
+++ b/test/hotspot/gtest/runtime/test_os_linux.cpp
@ -0,0 +1,495 @@
+/*
+ * Copyright (c) 2018, 2026, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+
+#ifdef LINUX
+
+#include "os_linux.hpp"
+#include "prims/jniCheck.hpp"
+#include "runtime/globals.hpp"
+#include "runtime/os.hpp"
+#include "utilities/align.hpp"
+#include "utilities/decoder.hpp"
+#include "concurrentTestRunner.inline.hpp"
+#include "testutils.hpp"
+#include "unittest.hpp"
+
+#include <sys/mman.h>
+#include <sys/prctl.h>
+
+static bool using_explicit_hugepages()  { return UseLargePages && !UseTransparentHugePages; }
+
+namespace {
+  static void small_page_write(void* addr, size_t size) {
+    size_t page_size = os::vm_page_size();
+
+    char* end = (char*)addr + size;
+    for (char* p = (char*)addr; p < end; p += page_size) {
+      *p = 1;
+    }
+  }
+
+  class HugeTlbfsMemory : private ::os::Linux {
+    char* const _ptr;
+    const size_t _size;
+   public:
+    static char* reserve_memory_special_huge_tlbfs(size_t bytes, size_t alignment, size_t page_size, char* req_addr, bool exec) {
+      return os::reserve_memory_special(bytes, alignment, page_size, req_addr, exec);
+    }
+    HugeTlbfsMemory(char* const ptr, size_t size) : _ptr(ptr), _size(size) { }
+    ~HugeTlbfsMemory() {
+      if (_ptr != nullptr) {
+        os::release_memory(_ptr, _size);
+      }
+    }
+  };
+
+  // have to use these functions, as gtest's _PRED macros don't like is_aligned
+  // nor (is_aligned<size_t, size_t>)
+  static bool is_size_aligned(size_t size, size_t alignment) {
+    return is_aligned(size, alignment);
+  }
+  static bool is_ptr_aligned(char* ptr, size_t alignment) {
+    return is_aligned(ptr, alignment);
+  }
+}
+
+TEST_VM(os_linux, reserve_memory_special_huge_tlbfs_size_aligned) {
+  if (!using_explicit_hugepages()) {
+    return;
+  }
+  size_t lp = os::large_page_size();
+
+  for (size_t size = lp; size <= lp * 10; size += lp) {
+    char* addr = HugeTlbfsMemory::reserve_memory_special_huge_tlbfs(size, lp, lp, nullptr, false);
+
+    if (addr != nullptr) {
+      HugeTlbfsMemory mr(addr, size);
+      small_page_write(addr, size);
+    }
+  }
+}
+
+TEST_VM(os_linux, reserve_memory_special_huge_tlbfs_size_not_aligned_without_addr) {
+  if (!using_explicit_hugepages()) {
+    return;
+  }
+  size_t lp = os::large_page_size();
+  size_t ag = os::vm_allocation_granularity();
+
+  // sizes to test
+  const size_t sizes[] = {
+    lp, lp + ag, lp + lp / 2, lp * 2,
+    lp * 2 + ag, lp * 2 - ag, lp * 2 + lp / 2,
+    lp * 10, lp * 10 + lp / 2
+  };
+  const int num_sizes = sizeof(sizes) / sizeof(size_t);
+  for (int i = 0; i < num_sizes; i++) {
+    const size_t size = sizes[i];
+    for (size_t alignment = ag; is_size_aligned(size, alignment); alignment *= 2) {
+      char* p = HugeTlbfsMemory::reserve_memory_special_huge_tlbfs(size, alignment, lp, nullptr, false);
+      if (p != nullptr) {
+        HugeTlbfsMemory mr(p, size);
+        EXPECT_PRED2(is_ptr_aligned, p, alignment) << " size = " << size;
+        small_page_write(p, size);
+      }
+    }
+  }
+}
+
+TEST_VM(os_linux, reserve_memory_special_huge_tlbfs_size_not_aligned_with_good_req_addr) {
+  if (!using_explicit_hugepages()) {
+    return;
+  }
+  size_t lp = os::large_page_size();
+  size_t ag = os::vm_allocation_granularity();
+
+  // sizes to test
+  const size_t sizes[] = {
+    lp, lp + ag, lp + lp / 2, lp * 2,
+    lp * 2 + ag, lp * 2 - ag, lp * 2 + lp / 2,
+    lp * 10, lp * 10 + lp / 2
+  };
+  const int num_sizes = sizeof(sizes) / sizeof(size_t);
+
+  // Pre-allocate an area as large as the largest allocation
+  // and aligned to the largest alignment we will be testing.
+  const size_t mapping_size = sizes[num_sizes - 1] * 2;
+  char* const mapping = (char*) ::mmap(nullptr, mapping_size,
+      PROT_NONE, MAP_PRIVATE|MAP_ANONYMOUS|MAP_NORESERVE,
+      -1, 0);
+  ASSERT_TRUE(mapping != MAP_FAILED) << " mmap failed, mapping_size = " << mapping_size;
+  // Unmap the mapping, it will serve as a value for a "good" req_addr
+  ::munmap(mapping, mapping_size);
+
+  for (int i = 0; i < num_sizes; i++) {
+    const size_t size = sizes[i];
+    for (size_t alignment = ag; is_size_aligned(size, alignment); alignment *= 2) {
+      // req_addr must be at least large page aligned.
+      char* const req_addr = align_up(mapping, MAX2(alignment, lp));
+      char* p = HugeTlbfsMemory::reserve_memory_special_huge_tlbfs(size, alignment, lp, req_addr, false);
+      if (p != nullptr) {
+        HugeTlbfsMemory mr(p, size);
+        ASSERT_EQ(req_addr, p) << " size = " << size << ", alignment = " << alignment;
+        small_page_write(p, size);
+      }
+    }
+  }
+}
+
+
+TEST_VM(os_linux, reserve_memory_special_huge_tlbfs_size_not_aligned_with_bad_req_addr) {
+  if (!using_explicit_hugepages()) {
+    return;
+  }
+  size_t lp = os::large_page_size();
+  size_t ag = os::vm_allocation_granularity();
+
+  // sizes to test
+  const size_t sizes[] = {
+    lp, lp + ag, lp + lp / 2, lp * 2,
+    lp * 2 + ag, lp * 2 - ag, lp * 2 + lp / 2,
+    lp * 10, lp * 10 + lp / 2
+  };
+  const int num_sizes = sizeof(sizes) / sizeof(size_t);
+
+  // Pre-allocate an area as large as the largest allocation
+  // and aligned to the largest alignment we will be testing.
+  const size_t mapping_size = sizes[num_sizes - 1] * 2;
+  char* const mapping = (char*) ::mmap(nullptr, mapping_size,
+      PROT_NONE, MAP_PRIVATE|MAP_ANONYMOUS|MAP_NORESERVE,
+      -1, 0);
+  ASSERT_TRUE(mapping != MAP_FAILED) << " mmap failed, mapping_size = " << mapping_size;
+  // Leave the mapping intact, it will server as "bad" req_addr
+
+  class MappingHolder {
+    char* const _mapping;
+    size_t _size;
+   public:
+    MappingHolder(char* mapping, size_t size) : _mapping(mapping), _size(size) { }
+    ~MappingHolder() {
+      ::munmap(_mapping, _size);
+    }
+  } holder(mapping, mapping_size);
+
+  for (int i = 0; i < num_sizes; i++) {
+    const size_t size = sizes[i];
+    for (size_t alignment = ag; is_size_aligned(size, alignment); alignment *= 2) {
+      // req_addr must be at least large page aligned.
+      char* const req_addr = align_up(mapping, MAX2(alignment, lp));
+      char* p = HugeTlbfsMemory::reserve_memory_special_huge_tlbfs(size, alignment, lp, req_addr, false);
+      HugeTlbfsMemory mr(p, size);
+      // as the area around req_addr contains already existing mappings, the API should always
+      // return null (as per contract, it cannot return another address)
+      EXPECT_TRUE(p == nullptr) << " size = " << size
+                             << ", alignment = " << alignment
+                             << ", req_addr = " << req_addr
+                             << ", p = " << p;
+    }
+  }
+}
+
+class TestReserveMemorySpecial : AllStatic {
+ public:
+  static void small_page_write(void* addr, size_t size) {
+    size_t page_size = os::vm_page_size();
+
+    char* end = (char*)addr + size;
+    for (char* p = (char*)addr; p < end; p += page_size) {
+      *p = 1;
+    }
+  }
+
+  static void test_reserve_memory_special_huge_tlbfs_size_aligned(size_t size, size_t alignment, size_t page_size) {
+    if (!using_explicit_hugepages()) {
+      return;
+    }
+    char* addr = os::reserve_memory_special(size, alignment, page_size, nullptr, false);
+    if (addr != nullptr) {
+      small_page_write(addr, size);
+      os::release_memory(addr, size);
+    }
+  }
+
+  static void test_reserve_memory_special_huge_tlbfs_size_aligned() {
+    if (!using_explicit_hugepages()) {
+      return;
+    }
+    size_t lp = os::large_page_size();
+    for (size_t size = lp; size <= lp * 10; size += lp) {
+      test_reserve_memory_special_huge_tlbfs_size_aligned(size, lp, lp);
+    }
+  }
+
+  static void test_reserve_memory_special_huge_tlbfs_size_not_aligned() {
+    size_t lp = os::large_page_size();
+    size_t ag = os::vm_allocation_granularity();
+
+    // sizes to test
+    const size_t sizes[] = {
+      lp, lp + ag, lp + lp / 2, lp * 2,
+      lp * 2 + ag, lp * 2 - ag, lp * 2 + lp / 2,
+      lp * 10, lp * 10 + lp / 2
+    };
+    const int num_sizes = sizeof(sizes) / sizeof(size_t);
+
+    // For each size/alignment combination, we test three scenarios:
+    // 1) with req_addr == nullptr
+    // 2) with a non-null req_addr at which we expect to successfully allocate
+    // 3) with a non-null req_addr which contains a pre-existing mapping, at which we
+    //    expect the allocation to either fail or to ignore req_addr
+
+    // Pre-allocate two areas; they shall be as large as the largest allocation
+    //  and aligned to the largest alignment we will be testing.
+    const size_t mapping_size = sizes[num_sizes - 1] * 2;
+    char* const mapping1 = (char*) ::mmap(nullptr, mapping_size,
+      PROT_NONE, MAP_PRIVATE|MAP_ANONYMOUS|MAP_NORESERVE,
+      -1, 0);
+    EXPECT_NE(mapping1, MAP_FAILED);
+
+    char* const mapping2 = (char*) ::mmap(nullptr, mapping_size,
+      PROT_NONE, MAP_PRIVATE|MAP_ANONYMOUS|MAP_NORESERVE,
+      -1, 0);
+    EXPECT_NE(mapping2, MAP_FAILED);
+
+    // Unmap the first mapping, but leave the second mapping intact: the first
+    // mapping will serve as a value for a "good" req_addr (case 2). The second
+    // mapping, still intact, as "bad" req_addr (case 3).
+    ::munmap(mapping1, mapping_size);
+
+    // Case 1
+    for (int i = 0; i < num_sizes; i++) {
+      const size_t size = sizes[i];
+      for (size_t alignment = ag; is_aligned(size, alignment); alignment *= 2) {
+        char* p = os::reserve_memory_special(size, alignment, lp, nullptr, false);
+        if (p != nullptr) {
+          EXPECT_TRUE(is_aligned(p, alignment));
+          small_page_write(p, size);
+          os::release_memory(p, size);
+        }
+      }
+    }
+
+    // Case 2
+    for (int i = 0; i < num_sizes; i++) {
+      const size_t size = sizes[i];
+      for (size_t alignment = ag; is_aligned(size, alignment); alignment *= 2) {
+        // req_addr must be at least large page aligned.
+        char* const req_addr = align_up(mapping1, MAX2(alignment, lp));
+        char* p = os::reserve_memory_special(size, alignment, lp, req_addr, false);
+        if (p != nullptr) {
+          EXPECT_EQ(p, req_addr);
+          small_page_write(p, size);
+          os::release_memory(p, size);
+        }
+      }
+    }
+
+    // Case 3
+    for (int i = 0; i < num_sizes; i++) {
+      const size_t size = sizes[i];
+      for (size_t alignment = ag; is_aligned(size, alignment); alignment *= 2) {
+        // req_addr must be at least large page aligned.
+        char* const req_addr = align_up(mapping2, MAX2(alignment, lp));
+        char* p = os::reserve_memory_special(size, alignment, lp, req_addr, false);
+        // as the area around req_addr contains already existing mappings, the API should always
+        // return nullptr (as per contract, it cannot return another address)
+        EXPECT_TRUE(p == nullptr);
+      }
+    }
+
+    ::munmap(mapping2, mapping_size);
+
+  }
+
+  static void test() {
+    if (!using_explicit_hugepages()) {
+      return;
+    }
+    test_reserve_memory_special_huge_tlbfs_size_aligned();
+    test_reserve_memory_special_huge_tlbfs_size_not_aligned();
+  }
+};
+
+TEST_VM(os_linux, reserve_memory_special) {
+  TestReserveMemorySpecial::test();
+}
+
+class ReserveMemorySpecialRunnable : public TestRunnable {
+public:
+  void runUnitTest() const {
+    TestReserveMemorySpecial::test();
+  }
+};
+
+TEST_VM(os_linux, reserve_memory_special_concurrent) {
+  if (UseLargePages) {
+    ReserveMemorySpecialRunnable runnable;
+    ConcurrentTestRunner testRunner(&runnable, 5, 3000);
+    testRunner.run();
+  }
+}
+
+TEST_VM(os_linux, pretouch_thp_and_use_concurrent) {
+  // Explicitly enable thp to test cocurrent system calls.
+  const size_t size = 1 * G;
+  const bool useThp = UseTransparentHugePages;
+  UseTransparentHugePages = true;
+  char* const heap = os::reserve_memory(size, mtTest);
+  EXPECT_NE(heap, nullptr);
+  EXPECT_TRUE(os::commit_memory(heap, size, false));
+
+  {
+    auto pretouch = [&](Thread*, int) {
+      os::pretouch_memory(heap, heap + size, os::vm_page_size());
+    };
+    auto useMemory = [&](Thread*, int) {
+      int* iptr = reinterpret_cast<int*>(heap);
+      for (int i = 0; i < 1000; i++) *iptr++ = i;
+    };
+    TestThreadGroup<decltype(pretouch)> pretouchThreads{pretouch, 4};
+    TestThreadGroup<decltype(useMemory)> useMemoryThreads{useMemory, 4};
+    useMemoryThreads.doit();
+    pretouchThreads.doit();
+    useMemoryThreads.join();
+    pretouchThreads.join();
+  }
+
+  int* iptr = reinterpret_cast<int*>(heap);
+  for (int i = 0; i < 1000; i++)
+    EXPECT_EQ(*iptr++, i);
+
+  os::uncommit_memory(heap, size, false);
+  os::release_memory(heap, size);
+  UseTransparentHugePages = useThp;
+}
+
+// Check that method JNI_CreateJavaVM is found.
+TEST(os_linux, addr_to_function_valid) {
+  char buf[128] = "";
+  int offset = -1;
+  address valid_function_pointer = (address)JNI_CreateJavaVM;
+  ASSERT_TRUE(os::dll_address_to_function_name(valid_function_pointer, buf, sizeof(buf), &offset, true));
+  ASSERT_THAT(buf, testing::HasSubstr("JNI_CreateJavaVM"));
+  ASSERT_TRUE(offset >= 0);
+}
+
+#if !defined(__clang_major__) || (__clang_major__ >= 5) // DWARF does not support Clang versions older than 5.0.
+// Test valid address of method ReportJNIFatalError in jniCheck.hpp. We should get "jniCheck.hpp" in the buffer and a valid line number.
+TEST_VM(os_linux, decoder_get_source_info_valid) {
+  char buf[128] = "";
+  int line = -1;
+  address valid_function_pointer = (address)ReportJNIFatalError;
+  ASSERT_TRUE(Decoder::get_source_info(valid_function_pointer, buf, sizeof(buf), &line));
+  EXPECT_STREQ(buf, "jniCheck.hpp");
+  ASSERT_TRUE(line > 0);
+}
+
+// Test invalid addresses. Should not cause harm and output buffer and line must contain "" and -1, respectively.
+TEST_VM(os_linux, decoder_get_source_info_invalid) {
+  char buf[128] = "";
+  int line = -1;
+  address invalid_function_pointers[] = { nullptr, (address)1, (address)&line };
+
+  for (address addr : invalid_function_pointers) {
+    strcpy(buf, "somestring");
+    line = 12;
+    // We should return false but do not crash or fail in any way.
+    ASSERT_FALSE(Decoder::get_source_info(addr, buf, sizeof(buf), &line));
+    ASSERT_TRUE(buf[0] == '\0'); // Should contain "" on error
+    ASSERT_TRUE(line == -1); // Should contain -1 on error
+  }
+}
+
+// Test with valid address but a too small buffer to store the entire filename. Should find generic <OVERFLOW> message
+// and a valid line number.
+TEST_VM(os_linux, decoder_get_source_info_valid_overflow) {
+  char buf[11] = "";
+  int line = -1;
+  address valid_function_pointer = (address)ReportJNIFatalError;
+  ASSERT_TRUE(Decoder::get_source_info(valid_function_pointer, buf, 11, &line));
+  EXPECT_STREQ(buf, "<OVERFLOW>");
+  ASSERT_TRUE(line > 0);
+}
+
+// Test with valid address but a too small buffer that can neither store the entire filename nor the generic <OVERFLOW>
+// message. We should find "L" as filename and a valid line number.
+TEST_VM(os_linux, decoder_get_source_info_valid_overflow_minimal) {
+  char buf[2] = "";
+  int line = -1;
+  address valid_function_pointer = (address)ReportJNIFatalError;
+  ASSERT_TRUE(Decoder::get_source_info(valid_function_pointer, buf, 2, &line));
+  EXPECT_STREQ(buf, "L"); // Overflow message does not fit, so we fall back to "L:line_number"
+  ASSERT_TRUE(line > 0); // Line should correctly be found and returned
+}
+#endif // clang
+
+#ifdef __GLIBC__
+#ifndef ADDRESS_SANITIZER
+TEST_VM(os_linux, glibc_mallinfo_wrapper) {
+  // Very basic test. Call it. That proves that resolution and invocation works.
+  os::Linux::glibc_mallinfo mi;
+  bool did_wrap = false;
+
+  void* p = os::malloc(2 * K, mtTest);
+  ASSERT_NOT_NULL(p);
+
+  os::Linux::get_mallinfo(&mi, &did_wrap);
+
+  // We should see total allocation values > 0
+  ASSERT_GE((mi.uordblks + mi.hblkhd), 2 * K);
+
+  // These values also should less than some reasonable size.
+  ASSERT_LT(mi.fordblks, 2 * G);
+  ASSERT_LT(mi.uordblks, 2 * G);
+  ASSERT_LT(mi.hblkhd, 2 * G);
+
+  os::free(p);
+}
+#endif // ADDRESS_SANITIZER
+#endif // __GLIBC__
+
+static void test_set_thread_name(const char* name, const char* expected) {
+  os::set_native_thread_name(name);
+  char buf[16];
+  int rc = prctl(PR_GET_NAME, buf);
+  ASSERT_EQ(0, rc);
+  ASSERT_STREQ(buf, expected);
+}
+
+TEST_VM(os_linux, set_thread_name) {
+  char buf[16];
+  // retrieve current name
+  int rc = prctl(PR_GET_NAME, buf);
+  ASSERT_EQ(0, rc);
+
+  test_set_thread_name("shortname", "shortname");
+  test_set_thread_name("012345678901234",  "012345678901234");
+  test_set_thread_name("0123456789012345", "0123456..012345");
+  test_set_thread_name("MyAllocationWorkerThread22", "MyAlloc..read22");
+
+  // restore current name
+  test_set_thread_name(buf, buf);
+}
+
+#endif // LINUX