[hwasan, asan] Intercept vfork.

Summary:
Intercept vfork on arm, aarch64, i386 and x86_64.

Reviewers: pcc, vitalybuka

Subscribers: kubamracek, mgorny, javed.absar, krytarowski, kristof.beyls, #sanitizers, llvm-commits

Tags: #sanitizers, #llvm

Differential Revision: https://reviews.llvm.org/D58533

llvm-svn: 355030

1 files changed, 8 insertions, 0 deletions

diff --git a/compiler-rt/include/sanitizer/hwasan_interface.h b/compiler-rt/include/sanitizer/hwasan_interface.h
index 731ffc4014a..104af4caa3d 100644
--- a/compiler-rt/include/sanitizer/hwasan_interface.h
+++ b/compiler-rt/include/sanitizer/hwasan_interface.h
@@ -50,6 +50,10 @@ extern "C" {
   // does would cause false reports.
   void __hwasan_handle_longjmp(const void *sp_dst);
 
+  // Set memory tag for the part of the current thread stack below sp_dst to
+  // zero. Call this in vfork() before returning in the parent process.
+  void __hwasan_handle_vfork(const void *sp_dst);
+
   // Libc hook for thread creation. Should be called in the child thread before
   // any instrumented code.
   void __hwasan_thread_enter();
@@ -65,6 +69,10 @@ extern "C" {
   // Print one-line report about the memory usage of the current process.
   void __hwasan_print_memory_usage();
 
+  /* Returns the offset of the first byte in the memory range that can not be
+   * accessed through the pointer in x, or -1 if the whole range is good. */
+  intptr_t __hwasan_test_shadow(const volatile void *x, size_t size);
+
   int __sanitizer_posix_memalign(void **memptr, size_t alignment, size_t size);
   void * __sanitizer_memalign(size_t alignment, size_t size);
   void * __sanitizer_aligned_alloc(size_t alignment, size_t size);