Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Jump to bottom

test: check that sysconf returns a positive value #44666

Merged
merged 1 commit into from Sep 25, 2022
Merged

test: check that sysconf returns a positive value #44666

Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Jump to
Jump to file
Failed to load files.
Diff view
Diff view
33 changes: 22 additions & 11 deletions test/cctest/test_crypto_clienthello.cc
View file
Open in desktop
Expand Up @@ -29,25 +29,38 @@
#endif
#endif

#if defined(USE_MPROTECT)
size_t GetPageSize() {
int page_size = sysconf(_SC_PAGE_SIZE);
EXPECT_GE(page_size, 1);
return page_size;
}
#elif defined(USE_VIRTUALPROTECT)
size_t GetPageSize() {
SYSTEM_INFO system_info;
GetSystemInfo(&system_info);
return system_info.dwPageSize;
}
#endif

template <size_t N>
class OverrunGuardedBuffer {
public:
OverrunGuardedBuffer() {
#if defined(USE_MPROTECT) || defined(USE_VIRTUALPROTECT)
size_t page = GetPageSize();
EXPECT_GE(page, N);
#endif
#ifdef USE_MPROTECT
// Place the packet right before a guard page, which, when accessed, causes
// a segmentation fault.
int page = sysconf(_SC_PAGE_SIZE);
EXPECT_GE(page, static_cast<int>(N));
alloc_base = static_cast<uint8_t*>(aligned_alloc(page, 2 * page));
EXPECT_NE(alloc_base, nullptr);
uint8_t* second_page = alloc_base + page;
EXPECT_EQ(mprotect(second_page, page, PROT_NONE), 0);
data_base = second_page - N;
#elif defined(USE_VIRTUALPROTECT)
// On Windows, it works almost the same way.
SYSTEM_INFO system_info;
GetSystemInfo(&system_info);
DWORD page = system_info.dwPageSize;
alloc_base = static_cast<uint8_t*>(
VirtualAlloc(nullptr, 2 * page, MEM_COMMIT, PAGE_READWRITE));
EXPECT_NE(alloc_base, nullptr);
Expand All @@ -70,16 +83,14 @@ class OverrunGuardedBuffer {
OverrunGuardedBuffer& operator=(const OverrunGuardedBuffer& other) = delete;

~OverrunGuardedBuffer() {
#if defined(USE_MPROTECT) || defined(USE_VIRTUALPROTECT)
size_t page = GetPageSize();
#endif
#ifdef USE_VIRTUALPROTECT
SYSTEM_INFO system_info;
GetSystemInfo(&system_info);
DWORD page = system_info.dwPageSize;
VirtualFree(alloc_base, 2 * system_info.dwPageSize, MEM_RELEASE);
VirtualFree(alloc_base, 2 * page, MEM_RELEASE);
#else
#ifdef USE_MPROTECT
// Revert page protection such that the memory can be free()'d.
int page = sysconf(_SC_PAGE_SIZE);
EXPECT_GE(page, static_cast<int>(N));
uint8_t* second_page = alloc_base + page;
EXPECT_EQ(mprotect(second_page, page, PROT_READ | PROT_WRITE), 0);
#endif
Expand Down