fix(macos): Fix thread safety in NSException capture

Sentry.xcodeproj/project.pbxproj

@@ -453,15 +453,13 @@
 		F44858132E03579D0013E63B /* SentryCrashDynamicLinker+Test.h in Headers */ = {isa = PBXBuildFile; fileRef = F44858122E0357940013E63B /* SentryCrashDynamicLinker+Test.h */; };
 		F44D2B5C2E6B7E8700FF31FA /* SentryProfilingScreenFramesHelper.h in Headers */ = {isa = PBXBuildFile; fileRef = F44D2B5A2E6B7E8700FF31FA /* SentryProfilingScreenFramesHelper.h */; };
 		F44D2B5D2E6B7E8700FF31FA /* SentryProfilingScreenFramesHelper.m in Sources */ = {isa = PBXBuildFile; fileRef = F44D2B5B2E6B7E8700FF31FA /* SentryProfilingScreenFramesHelper.m */; };
-		F452437E2DE60B71003E8F50 /* SentryUseNSExceptionCallstackWrapper.m in Sources */ = {isa = PBXBuildFile; fileRef = F452437D2DE60B71003E8F50 /* SentryUseNSExceptionCallstackWrapper.m */; };
-		F452438C2DE65BC0003E8F50 /* SentryUseNSExceptionCallstackWrapper.h in Headers */ = {isa = PBXBuildFile; fileRef = F452438B2DE65BC0003E8F50 /* SentryUseNSExceptionCallstackWrapper.h */; };
 		F459B01D2F2AB1480096AA8B /* SentryAppStartTrackerHelper.m in Sources */ = {isa = PBXBuildFile; fileRef = F459B01C2F2AB1480096AA8B /* SentryAppStartTrackerHelper.m */; };
 		F459B0242F2AB1560096AA8B /* SentryAppStartTrackerHelper.h in Headers */ = {isa = PBXBuildFile; fileRef = F459B0232F2AB1560096AA8B /* SentryAppStartTrackerHelper.h */; };
 		F485E2832F293E1A00B66F52 /* SentryUIViewControllerSwizzlingHelper.m in Sources */ = {isa = PBXBuildFile; fileRef = F485E2822F293E1A00B66F52 /* SentryUIViewControllerSwizzlingHelper.m */; };
 		F485E28A2F293E2900B66F52 /* SentryUIViewControllerSwizzlingHelper.h in Headers */ = {isa = PBXBuildFile; fileRef = F485E2892F293E2900B66F52 /* SentryUIViewControllerSwizzlingHelper.h */; };
 		F48F21F52EF1F05000E33FC1 /* SentryAppStartMeasurement+Private.h in Headers */ = {isa = PBXBuildFile; fileRef = F48F21F42EF1F04C00E33FC1 /* SentryAppStartMeasurement+Private.h */; };
-		F49D419C2DEA30C300D9244E /* SentryCrashExceptionApplicationHelper.h in Headers */ = {isa = PBXBuildFile; fileRef = F49D419B2DEA30B800D9244E /* SentryCrashExceptionApplicationHelper.h */; };
-		F49D419E2DEA3D0600D9244E /* SentryCrashExceptionApplicationHelper.m in Sources */ = {isa = PBXBuildFile; fileRef = F49D419D2DEA3D0300D9244E /* SentryCrashExceptionApplicationHelper.m */; };
+		F49D419C2DEA30C300D9244E /* SentryNSExceptionCaptureHelper.h in Headers */ = {isa = PBXBuildFile; fileRef = F49D419B2DEA30B800D9244E /* SentryNSExceptionCaptureHelper.h */; };
+		F49D419E2DEA3D0600D9244E /* SentryNSExceptionCaptureHelper.m in Sources */ = {isa = PBXBuildFile; fileRef = F49D419D2DEA3D0300D9244E /* SentryNSExceptionCaptureHelper.m */; };
 		F4F33D4C2F1F35BA00753FE2 /* SentryNSDataSwizzlingHelper.m in Sources */ = {isa = PBXBuildFile; fileRef = F4F33D4A2F1F35BA00753FE2 /* SentryNSDataSwizzlingHelper.m */; };
 		F4F33D4D2F1F35BA00753FE2 /* SentryNSFileManagerSwizzlingHelper.m in Sources */ = {isa = PBXBuildFile; fileRef = F4F33D4B2F1F35BA00753FE2 /* SentryNSFileManagerSwizzlingHelper.m */; };
 		FA24E02A2EBBF6F900EFD92E /* SentryOptionsObjC.h in Headers */ = {isa = PBXBuildFile; fileRef = FA24E0292EBBF6F500EFD92E /* SentryOptionsObjC.h */; };
@@ -1115,15 +1113,13 @@
 		F44858122E0357940013E63B /* SentryCrashDynamicLinker+Test.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; path = "SentryCrashDynamicLinker+Test.h"; sourceTree = "<group>"; };
 		F44D2B5A2E6B7E8700FF31FA /* SentryProfilingScreenFramesHelper.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; path = SentryProfilingScreenFramesHelper.h; sourceTree = "<group>"; };
 		F44D2B5B2E6B7E8700FF31FA /* SentryProfilingScreenFramesHelper.m */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.objc; path = SentryProfilingScreenFramesHelper.m; sourceTree = "<group>"; };
-		F452437D2DE60B71003E8F50 /* SentryUseNSExceptionCallstackWrapper.m */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.objc; path = SentryUseNSExceptionCallstackWrapper.m; sourceTree = "<group>"; };
-		F452438B2DE65BC0003E8F50 /* SentryUseNSExceptionCallstackWrapper.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; name = SentryUseNSExceptionCallstackWrapper.h; path = include/SentryUseNSExceptionCallstackWrapper.h; sourceTree = "<group>"; };
 		F459B01C2F2AB1480096AA8B /* SentryAppStartTrackerHelper.m */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.objc; path = SentryAppStartTrackerHelper.m; sourceTree = "<group>"; };
 		F459B0232F2AB1560096AA8B /* SentryAppStartTrackerHelper.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; name = SentryAppStartTrackerHelper.h; path = include/SentryAppStartTrackerHelper.h; sourceTree = "<group>"; };
 		F485E2822F293E1A00B66F52 /* SentryUIViewControllerSwizzlingHelper.m */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.objc; path = SentryUIViewControllerSwizzlingHelper.m; sourceTree = "<group>"; };
 		F485E2892F293E2900B66F52 /* SentryUIViewControllerSwizzlingHelper.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; name = SentryUIViewControllerSwizzlingHelper.h; path = include/SentryUIViewControllerSwizzlingHelper.h; sourceTree = "<group>"; };
 		F48F21F42EF1F04C00E33FC1 /* SentryAppStartMeasurement+Private.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; name = "SentryAppStartMeasurement+Private.h"; path = "include/SentryAppStartMeasurement+Private.h"; sourceTree = "<group>"; };
-		F49D419B2DEA30B800D9244E /* SentryCrashExceptionApplicationHelper.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; name = SentryCrashExceptionApplicationHelper.h; path = include/SentryCrashExceptionApplicationHelper.h; sourceTree = "<group>"; };
-		F49D419D2DEA3D0300D9244E /* SentryCrashExceptionApplicationHelper.m */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.objc; path = SentryCrashExceptionApplicationHelper.m; sourceTree = "<group>"; };
+		F49D419B2DEA30B800D9244E /* SentryNSExceptionCaptureHelper.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; name = SentryNSExceptionCaptureHelper.h; path = include/SentryNSExceptionCaptureHelper.h; sourceTree = "<group>"; };
+		F49D419D2DEA3D0300D9244E /* SentryNSExceptionCaptureHelper.m */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.objc; path = SentryNSExceptionCaptureHelper.m; sourceTree = "<group>"; };
 		F4F33D4A2F1F35BA00753FE2 /* SentryNSDataSwizzlingHelper.m */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.objc; path = SentryNSDataSwizzlingHelper.m; sourceTree = "<group>"; };
 		F4F33D4B2F1F35BA00753FE2 /* SentryNSFileManagerSwizzlingHelper.m */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.objc; path = SentryNSFileManagerSwizzlingHelper.m; sourceTree = "<group>"; };
 		F4F33D4E2F1F35C500753FE2 /* SentryNSDataSwizzlingHelper.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; name = SentryNSDataSwizzlingHelper.h; path = include/SentryNSDataSwizzlingHelper.h; sourceTree = "<group>"; };
@@ -1401,8 +1397,8 @@
 			children = (
 				632F434E1F581D5400A18A36 /* SentryCrashExceptionApplication.h */,
 				632F434F1F581D5400A18A36 /* SentryCrashExceptionApplication.m */,
-				F49D419B2DEA30B800D9244E /* SentryCrashExceptionApplicationHelper.h */,
-				F49D419D2DEA3D0300D9244E /* SentryCrashExceptionApplicationHelper.m */,
+				F49D419B2DEA30B800D9244E /* SentryNSExceptionCaptureHelper.h */,
+				F49D419D2DEA3D0300D9244E /* SentryNSExceptionCaptureHelper.m */,
 				6344DDB21EC309E000D9160D /* SentryCrashReportSink.h */,
 				6344DDB31EC309E000D9160D /* SentryCrashReportSink.m */,
 				6344DDB71EC3115C00D9160D /* SentryCrashReportConverter.h */,
@@ -1505,8 +1501,6 @@
 				844EDC75294144DB00C86F34 /* SentrySystemWrapper.mm */,
 				FAB359972E05D7E90083D5E3 /* SentryEventSwiftHelper.h */,
 				FAB359992E05D8080083D5E3 /* SentryEventSwiftHelper.m */,
-				F452438B2DE65BC0003E8F50 /* SentryUseNSExceptionCallstackWrapper.h */,
-				F452437D2DE60B71003E8F50 /* SentryUseNSExceptionCallstackWrapper.m */,
 			);
 			name = Helper;
 			sourceTree = "<group>";
@@ -2366,7 +2360,7 @@
 				84AF45A629A7FFA500FBB177 /* SentryProfiledTracerConcurrency.h in Headers */,
 				8EAE980B261E9F530073B6B3 /* SentryPerformanceTracker.h in Headers */,
 				63FE718520DA4C1100CDBAE8 /* SentryCrashC.h in Headers */,
-				F49D419C2DEA30C300D9244E /* SentryCrashExceptionApplicationHelper.h in Headers */,
+				F49D419C2DEA30C300D9244E /* SentryNSExceptionCaptureHelper.h in Headers */,
 				A8AFFCCD29069C3E00967CD7 /* SentryHttpStatusCodeRange.h in Headers */,
 				FAAB95DE2EA1EB470030A2DB /* SentryDeviceContextKeys.h in Headers */,
 				D83D079B2B7F9D1C00CC9674 /* SentryMsgPackSerializer.h in Headers */,
@@ -2486,7 +2480,6 @@
 				63FE716F20DA4C1100CDBAE8 /* SentryCrashCPU_Apple.h in Headers */,
 				639FCFA81EBC80CC00778193 /* SentryFrame.h in Headers */,
 				D8BFE37229A3782F002E73F3 /* SentryTimeToDisplayTracker.h in Headers */,
-				F452438C2DE65BC0003E8F50 /* SentryUseNSExceptionCallstackWrapper.h in Headers */,
 				63FE716D20DA4C1100CDBAE8 /* SentryCrashSysCtl.h in Headers */,
 				639889BB1EDED18400EA7442 /* SentrySwizzle.h in Headers */,
 				FA7206DF2E0B37850072FDD4 /* SentryProfileCollector.h in Headers */,
@@ -2900,7 +2893,7 @@
 				63FE712F20DA4C1100CDBAE8 /* SentryCrashSysCtl.c in Sources */,
 				7B3B473825D6CC7E00D01640 /* SentryNSError.m in Sources */,
 				621AE74D2C626C510012E730 /* SentryANRTrackerV2.m in Sources */,
-				F49D419E2DEA3D0600D9244E /* SentryCrashExceptionApplicationHelper.m in Sources */,
+				F49D419E2DEA3D0600D9244E /* SentryNSExceptionCaptureHelper.m in Sources */,
 				D8ACE3C82762187200F5A213 /* SentryFileIOTrackerHelper.m in Sources */,
 				D8B088B729C9E3FF00213258 /* SentryTracerConfiguration.m in Sources */,
 				FA7206E12E0B37C80072FDD4 /* SentryProfileCollector.mm in Sources */,
@@ -3000,7 +2993,6 @@
 				62C316832B1F2EA1000D7031 /* SentryDelayedFramesTracker.m in Sources */,
 				D8BFE37329A3782F002E73F3 /* SentryTimeToDisplayTracker.m in Sources */,
 				6334314320AD9AE40077E581 /* SentryMechanism.m in Sources */,
-				F452437E2DE60B71003E8F50 /* SentryUseNSExceptionCallstackWrapper.m in Sources */,
 				63FE70D320DA4C1000CDBAE8 /* SentryCrashMonitor_AppState.c in Sources */,
 				639FCFA51EBC809A00778193 /* SentryStacktrace.m in Sources */,
 				84A898542E163072009A551E /* SentryProfileConfiguration.m in Sources */,

Sources/Sentry/SentryClient.m

@@ -30,7 +30,6 @@
 #import "SentryTransport.h"
 #import "SentryTransportAdapter.h"
 #import "SentryTransportFactory.h"
-#import "SentryUseNSExceptionCallstackWrapper.h"
 #import "SentryUser.h"
 
 #if SENTRY_HAS_UIKIT
@@ -184,14 +183,6 @@ - (SentryEvent *)buildExceptionEvent:(NSException *)exception
 
     event.exceptions = @[ sentryException ];
 
-#if TARGET_OS_OSX
-    // When a exception class is SentryUseNSExceptionCallstackWrapper, we should use the thread from
-    // it
-    if ([exception isKindOfClass:[SentryUseNSExceptionCallstackWrapper class]]) {
-        event.threads = [(SentryUseNSExceptionCallstackWrapper *)exception buildThreads];
-    }
-#endif
-
     [self setUserInfo:exception.userInfo withEvent:event];
     return event;
 }

Sources/Sentry/SentryCrashExceptionApplication.m

@@ -3,8 +3,14 @@
 #if TARGET_OS_OSX && !SENTRY_NO_UI_FRAMEWORK
 
 #    import "SentryCrashExceptionApplication.h"
-#    import "SentryCrashExceptionApplicationHelper.h"
+#    import "SentryNSExceptionCaptureHelper.h"
 #    import "SentryUncaughtNSExceptions.h"
+#    import <AppKit/NSApplication.h>
+
+// Private AppKit method called on the application instance during CATransaction flush.
+@interface NSApplication (SentryCrashOnException)
+- (void)_crashOnException:(NSException *)exception;
+@end
 
 @implementation SentryCrashExceptionApplication
 
@@ -13,13 +19,15 @@ - (void)reportException:(NSException *)exception
     [SentryUncaughtNSExceptions configureCrashOnExceptions];
     // We cannot test an NSApplication because you create more than one at a time, so we use a
     // helper to hold the logic.
-    [SentryCrashExceptionApplicationHelper reportException:exception];
+    [SentryNSExceptionCaptureHelper reportException:exception];
     [super reportException:exception];
+    [SentryNSExceptionCaptureHelper reportExceptionDidFinish];
 }
 
 - (void)_crashOnException:(NSException *)exception
 {
-    [SentryCrashExceptionApplicationHelper _crashOnException:exception];
+    [SentryNSExceptionCaptureHelper crashOnException:exception];
+    [super _crashOnException:exception];
 }
 
 @end

Sources/Sentry/SentryNSExceptionCaptureHelper.m

@@ -0,0 +1,47 @@
+#import <Foundation/Foundation.h>
+
+#if TARGET_OS_OSX && !SENTRY_NO_UI_FRAMEWORK
+
+#    import "SentryCrash.h"
+#    import "SentryNSExceptionCaptureHelper.h"
+#    import "SentrySwift.h"
+#    import <stdatomic.h>
+
+@implementation SentryNSExceptionCaptureHelper
+
+// Thread-safe flag to prevent duplicate exception captures when
+// _crashOnException: is called from within reportException:
+static _Atomic BOOL _insideReportException = NO;
+
++ (void)reportException:(NSException *)exception
+{
+    atomic_store(&_insideReportException, YES);
+    [self captureException:exception];
+}
+
++ (void)reportExceptionDidFinish
+{
+    atomic_store(&_insideReportException, NO);
+}
+
++ (void)crashOnException:(NSException *)exception
+{
+    // When called from within reportException: (i.e., [super reportException:] internally
+    // dispatches to _crashOnException: when NSApplicationCrashOnExceptions is YES),
+    // the exception was already captured, so skip to avoid duplicate reports.
+    if (!atomic_load(&_insideReportException)) {
+        [self captureException:exception];
+    }
+}
+
++ (void)captureException:(NSException *)exception
+{
+    SentryCrashSwift *crash = SentryDependencyContainer.sharedInstance.crashReporter;
+    if (nil != crash.uncaughtExceptionHandler && nil != exception) {
+        crash.uncaughtExceptionHandler(exception);
+    }
+}
+
+@end
+
+#endif // TARGET_OS_OSX

Sources/Sentry/SentrySDKInternal.m

@@ -17,7 +17,6 @@
 #import "SentrySpanInternal.h"
 #import "SentrySwift.h"
 #import "SentryTransactionContext.h"
-#import "SentryUseNSExceptionCallstackWrapper.h"
 
 #if TARGET_OS_OSX
 #    import "SentryCrashExceptionApplication.h"
@@ -358,22 +357,6 @@ + (SentryId *)captureException:(NSException *)exception withScope:(SentryScope *
     return [SentrySDKInternal.currentHub captureException:exception withScope:scope];
 }
 
-#if TARGET_OS_OSX
-
-+ (SentryId *)captureCrashOnException:(NSException *)exception
-{
-    SentryUseNSExceptionCallstackWrapper *wrappedException =
-        [[SentryUseNSExceptionCallstackWrapper alloc]
-                        initWithName:exception.name
-                              reason:exception.reason
-                            userInfo:exception.userInfo
-            callStackReturnAddresses:exception.callStackReturnAddresses];
-    return [SentrySDKInternal captureException:wrappedException
-                                     withScope:SentrySDKInternal.currentHub.scope];
-}
-
-#endif // TARGET_OS_OSX
-
 + (SentryId *)captureMessage:(NSString *)message
 {
     return [SentrySDKInternal captureMessage:message withScope:SentrySDKInternal.currentHub.scope];

Sources/Sentry/SentryUncaughtNSExceptions.m

@@ -2,9 +2,10 @@
 
 #if TARGET_OS_OSX && !SENTRY_NO_UI_FRAMEWORK
 
-#    import "SentryCrash.h"
+#    import <objc/runtime.h>
+
 #    import "SentryInternalDefines.h"
-#    import "SentrySwift.h"
+#    import "SentryNSExceptionCaptureHelper.h"
 #    import "SentrySwizzle.h"
 #    import "SentryUncaughtNSExceptions.h"
 #    import <AppKit/NSApplication.h>
@@ -26,26 +27,64 @@ + (void)swizzleNSApplicationReportException
     SEL selector = NSSelectorFromString(@"reportException:");
     SentrySwizzleInstanceMethod(NSApplication, selector, SentrySWReturnType(void),
         SentrySWArguments(NSException * exception), SentrySWReplacement({
-            [SentryUncaughtNSExceptions capture:exception];
-            return SentrySWCallOriginal(exception);
+            [SentryNSExceptionCaptureHelper reportException:exception];
+            SentrySWCallOriginal(exception);
+            [SentryNSExceptionCaptureHelper reportExceptionDidFinish];
         }),
         SentrySwizzleModeOncePerClassAndSuperclasses, (void *)selector);
 #    pragma clang diagnostic pop
 }
 
-+ (void)capture:(nullable NSException *)exception
++ (void)swizzleNSApplicationCrashOnException
 {
-    SentryCrashSwift *crash = SentryDependencyContainer.sharedInstance.crashReporter;
-
-    if (crash.uncaughtExceptionHandler == nil) {
-        return;
-    }
+    // SentrySwizzleClassMethod has no built-in deduplication, so guard against repeated SDK starts.
+    static dispatch_once_t onceToken;
+    dispatch_once(&onceToken, ^{
+#    pragma clang diagnostic push
+#    pragma clang diagnostic ignored "-Wshadow"
+#    if SENTRY_TEST || SENTRY_TEST_CI
+#        pragma clang diagnostic ignored "-Wunused-variable"
+#    endif
+        // AppKit calls _crashOnException: when an exception is caught during CATransaction flush
+        // or view layout, bypassing reportException: entirely. Depending on macOS version, AppKit
+        // may call the class method +[NSApplication _crashOnException:] or the instance method
+        // -[NSApp _crashOnException:], so we swizzle both.
+        //
+        // SentryNSExceptionCaptureHelper handles deduplication: when _crashOnException: is
+        // called from within reportException: (e.g., when NSApplicationCrashOnExceptions is YES),
+        // the exception is only captured once.
+        SEL selector = NSSelectorFromString(@"_crashOnException:");
 
-    if (exception == nil) {
-        return;
-    }
+        // _crashOnException: is a private AppKit method that may not exist on all macOS versions.
+        // Only swizzle if the method is actually present on the class/instance.
+        if (class_getClassMethod([NSApplication class], selector)) {
+            SentrySwizzleClassMethod(NSApplication, selector, SentrySWReturnType(void),
+                SentrySWArguments(NSException * exception), SentrySWReplacement({
+                    [SentryNSExceptionCaptureHelper crashOnException:exception];
+#    if SENTRY_TEST || SENTRY_TEST_CI
+                    // Don't call the original in tests as it would abort() the process.
+                    swizzleInfo.originalCalled = YES;
+#    else
+                    return SentrySWCallOriginal(exception);
+#    endif
+                }));
+        }
 
-    crash.uncaughtExceptionHandler(SENTRY_UNWRAP_NULLABLE(NSException, exception));
+        if (class_getInstanceMethod([NSApplication class], selector)) {
+            SentrySwizzleInstanceMethod(NSApplication, selector, SentrySWReturnType(void),
+                SentrySWArguments(NSException * exception), SentrySWReplacement({
+                    [SentryNSExceptionCaptureHelper crashOnException:exception];
+#    if SENTRY_TEST || SENTRY_TEST_CI
+                    // Don't call the original in tests as it would abort() the process.
+                    swizzleInfo.originalCalled = YES;
+#    else
+                    return SentrySWCallOriginal(exception);
+#    endif
+                }),
+                SentrySwizzleModeOncePerClassAndSuperclasses, (void *)selector);
+        }
+#    pragma clang diagnostic pop
+    });
 }
 
 @end