fix: avoid call to possibly crashing mach_thread_deallocate

CHANGELOG.md

@@ -6,9 +6,10 @@
 
 - Add thread id and name to span data (#3359)
 
-### Improvements
+### Fixes
 
 - Stop sending empty thread names (#3361)
+- Work around edge case with a thread info kernel call sometimes returning invalid data, leading to a crash (#3364)
 
 ## 8.14.2
 

Sources/Sentry/SentryBacktrace.cpp

@@ -68,6 +68,7 @@ namespace profiling {
         } else {
             current = getFrameAddress(&machineContext);
         }
+
         // Even if this bounds check passes, the frame pointer address could still be invalid if the
         // thread was suspended in an inconsistent state. The best we can do is to detect these
         // situations at symbolication time on the server and filter them out -- there's not an easy
@@ -76,6 +77,7 @@ namespace profiling {
         if (UNLIKELY(!isValidFrame(current, bounds))) {
             return 0;
         }
+
         bool reachedEndOfStack = false;
         while (depth < maxDepth) {
             const auto frame = reinterpret_cast<StackFrame *>(current);
@@ -92,6 +94,7 @@ namespace profiling {
                 break;
             }
         }
+
         if (LIKELY(reachedEndOfStackPtr != nullptr)) {
             *reachedEndOfStackPtr = reachedEndOfStack;
         }

Sources/Sentry/SentryThreadHandle.cpp

@@ -44,9 +44,8 @@ namespace profiling {
     std::unique_ptr<ThreadHandle>
     ThreadHandle::current() noexcept
     {
-        const auto port = mach_thread_self();
-        SENTRY_PROF_LOG_KERN_RETURN(mach_port_deallocate(mach_task_self(), port));
-        return std::make_unique<ThreadHandle>(port);
+        const auto thread = pthread_mach_thread_np(pthread_self());
+        return std::make_unique<ThreadHandle>(thread);
     }
 
     std::vector<std::unique_ptr<ThreadHandle>>