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-rw-r--r--compiler-rt/lib/hwasan/hwasan_thread.cpp127
1 files changed, 127 insertions, 0 deletions
diff --git a/compiler-rt/lib/hwasan/hwasan_thread.cpp b/compiler-rt/lib/hwasan/hwasan_thread.cpp
new file mode 100644
index 000000000000..cabf614c005c
--- /dev/null
+++ b/compiler-rt/lib/hwasan/hwasan_thread.cpp
@@ -0,0 +1,127 @@
+
+#include "hwasan.h"
+#include "hwasan_mapping.h"
+#include "hwasan_thread.h"
+#include "hwasan_poisoning.h"
+#include "hwasan_interface_internal.h"
+
+#include "sanitizer_common/sanitizer_file.h"
+#include "sanitizer_common/sanitizer_placement_new.h"
+#include "sanitizer_common/sanitizer_tls_get_addr.h"
+
+
+namespace __hwasan {
+
+static u32 RandomSeed() {
+ u32 seed;
+ do {
+ if (UNLIKELY(!GetRandom(reinterpret_cast<void *>(&seed), sizeof(seed),
+ /*blocking=*/false))) {
+ seed = static_cast<u32>(
+ (NanoTime() >> 12) ^
+ (reinterpret_cast<uptr>(__builtin_frame_address(0)) >> 4));
+ }
+ } while (!seed);
+ return seed;
+}
+
+void Thread::InitRandomState() {
+ random_state_ = flags()->random_tags ? RandomSeed() : unique_id_;
+
+ // Push a random number of zeros onto the ring buffer so that the first stack
+ // tag base will be random.
+ for (tag_t i = 0, e = GenerateRandomTag(); i != e; ++i)
+ stack_allocations_->push(0);
+}
+
+void Thread::Init(uptr stack_buffer_start, uptr stack_buffer_size) {
+ static u64 unique_id;
+ unique_id_ = unique_id++;
+ if (auto sz = flags()->heap_history_size)
+ heap_allocations_ = HeapAllocationsRingBuffer::New(sz);
+
+ HwasanTSDThreadInit(); // Only needed with interceptors.
+ uptr *ThreadLong = GetCurrentThreadLongPtr();
+ // The following implicitly sets (this) as the current thread.
+ stack_allocations_ = new (ThreadLong)
+ StackAllocationsRingBuffer((void *)stack_buffer_start, stack_buffer_size);
+ // Check that it worked.
+ CHECK_EQ(GetCurrentThread(), this);
+
+ // ScopedTaggingDisable needs GetCurrentThread to be set up.
+ ScopedTaggingDisabler disabler;
+
+ uptr tls_size;
+ uptr stack_size;
+ GetThreadStackAndTls(IsMainThread(), &stack_bottom_, &stack_size, &tls_begin_,
+ &tls_size);
+ stack_top_ = stack_bottom_ + stack_size;
+ tls_end_ = tls_begin_ + tls_size;
+
+ if (stack_bottom_) {
+ int local;
+ CHECK(AddrIsInStack((uptr)&local));
+ CHECK(MemIsApp(stack_bottom_));
+ CHECK(MemIsApp(stack_top_ - 1));
+ }
+
+ if (flags()->verbose_threads) {
+ if (IsMainThread()) {
+ Printf("sizeof(Thread): %zd sizeof(HeapRB): %zd sizeof(StackRB): %zd\n",
+ sizeof(Thread), heap_allocations_->SizeInBytes(),
+ stack_allocations_->size() * sizeof(uptr));
+ }
+ Print("Creating : ");
+ }
+}
+
+void Thread::ClearShadowForThreadStackAndTLS() {
+ if (stack_top_ != stack_bottom_)
+ TagMemory(stack_bottom_, stack_top_ - stack_bottom_, 0);
+ if (tls_begin_ != tls_end_)
+ TagMemory(tls_begin_, tls_end_ - tls_begin_, 0);
+}
+
+void Thread::Destroy() {
+ if (flags()->verbose_threads)
+ Print("Destroying: ");
+ AllocatorSwallowThreadLocalCache(allocator_cache());
+ ClearShadowForThreadStackAndTLS();
+ if (heap_allocations_)
+ heap_allocations_->Delete();
+ DTLS_Destroy();
+}
+
+void Thread::Print(const char *Prefix) {
+ Printf("%sT%zd %p stack: [%p,%p) sz: %zd tls: [%p,%p)\n", Prefix,
+ unique_id_, this, stack_bottom(), stack_top(),
+ stack_top() - stack_bottom(),
+ tls_begin(), tls_end());
+}
+
+static u32 xorshift(u32 state) {
+ state ^= state << 13;
+ state ^= state >> 17;
+ state ^= state << 5;
+ return state;
+}
+
+// Generate a (pseudo-)random non-zero tag.
+tag_t Thread::GenerateRandomTag() {
+ if (tagging_disabled_) return 0;
+ tag_t tag;
+ do {
+ if (flags()->random_tags) {
+ if (!random_buffer_)
+ random_buffer_ = random_state_ = xorshift(random_state_);
+ CHECK(random_buffer_);
+ tag = random_buffer_ & 0xFF;
+ random_buffer_ >>= 8;
+ } else {
+ tag = random_state_ = (random_state_ + 1) & 0xFF;
+ }
+ } while (!tag);
+ return tag;
+}
+
+} // namespace __hwasan