1 files changed, 9 insertions, 6 deletions
diff --git a/lib/sanitizer_common/sanitizer_stacktrace.cc b/lib/sanitizer_common/sanitizer_stacktrace.cc
index 7862575b37bbd..7ad1f1f25abdc 100644
--- a/lib/sanitizer_common/sanitizer_stacktrace.cc
+++ b/lib/sanitizer_common/sanitizer_stacktrace.cc
@@ -40,11 +40,6 @@ void BufferedStackTrace::Init(const uptr *pcs, uptr cnt, uptr extra_top_pc) {
   top_frame_bp = 0;
 }
 
-// Check if given pointer points into allocated stack area.
-static inline bool IsValidFrame(uptr frame, uptr stack_top, uptr stack_bottom) {
-  return frame > stack_bottom && frame < stack_top - 2 * sizeof (uhwptr);
-}
-
 // In GCC on ARM bp points to saved lr, not fp, so we should check the next
 // cell in stack to be a saved frame pointer. GetCanonicFrame returns the
 // pointer to saved frame pointer in any case.
@@ -71,6 +66,7 @@ static inline uhwptr *GetCanonicFrame(uptr bp,
 
 void BufferedStackTrace::FastUnwindStack(uptr pc, uptr bp, uptr stack_top,
                                          uptr stack_bottom, u32 max_depth) {
+  const uptr kPageSize = GetPageSizeCached();
   CHECK_GE(max_depth, 2);
   trace_buffer[0] = pc;
   size = 1;
@@ -92,9 +88,16 @@ void BufferedStackTrace::FastUnwindStack(uptr pc, uptr bp, uptr stack_top,
         !IsAligned((uptr)caller_frame, sizeof(uhwptr)))
       break;
     uhwptr pc1 = caller_frame[2];
+#elif defined(__s390__)
+    uhwptr pc1 = frame[14];
 #else
     uhwptr pc1 = frame[1];
 #endif
+    // Let's assume that any pointer in the 0th page (i.e. <0x1000 on i386 and
+    // x86_64) is invalid and stop unwinding here.  If we're adding support for
+    // a platform where this isn't true, we need to reconsider this check.
+    if (pc1 < kPageSize)
+      break;
     if (pc1 != pc) {
       trace_buffer[size++] = (uptr) pc1;
     }
@@ -118,7 +121,7 @@ void BufferedStackTrace::PopStackFrames(uptr count) {
 uptr BufferedStackTrace::LocatePcInTrace(uptr pc) {
   // Use threshold to find PC in stack trace, as PC we want to unwind from may
   // slightly differ from return address in the actual unwinded stack trace.
-  const int kPcThreshold = 320;
+  const int kPcThreshold = 350;
   for (uptr i = 0; i < size; ++i) {
     if (MatchPc(pc, trace[i], kPcThreshold))
       return i;