Merge pull request #1597 from bugsnag/PLAT-11112-check-app-version

[Plat-11112] check app version when detecting OOMs

Bugsnag/Helpers/BSGRunContext.h

@@ -19,7 +19,7 @@
 // During development this is not strictly necessary since last run's data will
 // not be loaded if the struct's size has changed.
 //
-#define BSGRUNCONTEXT_VERSION 4
+#define BSGRUNCONTEXT_VERSION 5
 
 struct BSGRunContext {
     long structVersion;
@@ -50,6 +50,7 @@ struct BSGRunContext {
     unsigned long long memoryAvailable;
     unsigned long long memoryFootprint;
     unsigned long long memoryLimit;
+    char bundleVersion[32]; // Won't actually get this long but just to be sure.
 };
 
 /// Information about the current run of the app / process.

Bugsnag/Helpers/BSGRunContext.m

@@ -71,7 +71,13 @@ static void InitRunContext(void) {
     if (image && image->uuid) {
         uuid_copy(bsg_runContext->machoUUID, image->uuid);
     }
-
+
+    NSString *bundleVersion = [[[NSBundle mainBundle] infoDictionary] objectForKey:@"CFBundleVersion"];
+    const char *bundleVersionStr = (const char*)[bundleVersion cStringUsingEncoding:NSUTF8StringEncoding];
+    if (bundleVersionStr != nil) {
+        bsg_safe_strncpy(bsg_runContext->bundleVersion, bundleVersionStr, sizeof(bsg_runContext->bundleVersion));
+    }
+
     if ([NSThread isMainThread]) {
         bsg_runContext->isActive = GetIsActive();
     } else {
@@ -487,8 +493,13 @@ bool BSGRunContextWasKilled(void) {
     if (bsg_lastRunContext->bootTime != bsg_runContext->bootTime) {
         return NO; // The app may have been terminated due to the reboot
     }
-    
+
     // Ignore unexpected terminations due to the app being upgraded
+    if (strncmp(bsg_lastRunContext->bundleVersion,
+                bsg_runContext->bundleVersion,
+                sizeof(bsg_runContext->bundleVersion)) != 0) {
+        return NO;
+    }
     if (uuid_compare(bsg_lastRunContext->machoUUID, bsg_runContext->machoUUID)) {
         return NO;
     }
@@ -516,10 +527,13 @@ bool BSGRunContextWasKilled(void) {
 
 #define SIZEOF_STRUCT sizeof(struct BSGRunContext)
 
-static struct BSGRunContext fallback;
-struct BSGRunContext *bsg_runContext = &fallback;
+static struct BSGRunContext bsg_runContext_fallback;
+struct BSGRunContext *bsg_runContext = &bsg_runContext_fallback;
 
-const struct BSGRunContext *bsg_lastRunContext;
+static struct BSGRunContext bsg_lastRunContext_fallback = {
+    .structVersion = ~0,
+};
+const struct BSGRunContext *bsg_lastRunContext = &bsg_lastRunContext_fallback;
 
 /// Opens the file and disables content protection, returning -1 on error.
 static int OpenFile(NSString *_Nonnull path) {

Bugsnag/Helpers/BSGUtils.h

@@ -39,6 +39,12 @@ static inline NSString * _Nullable BSGStringFromClass(Class _Nullable cls) {
     return cls ? NSStringFromClass((Class _Nonnull)cls) : nil;
 }
 
+/**
+ * Copy characters from src to dst, up to a maximum of length bytes (including the NUL terminator).
+ * Unlike strncpy, this function always ensures that dst is NUL terminated (if length > 0).
+ */
+void bsg_safe_strncpy(char *dst, const char *src, size_t length);
+
 NS_ASSUME_NONNULL_END
 
 __END_DECLS

Bugsnag/Helpers/BSGUtils.m

@@ -10,6 +10,13 @@
 
 #import "BugsnagLogger.h"
 
+void bsg_safe_strncpy(char *dst, const char *src, size_t length) {
+    if (length > 0) {
+        strncpy(dst, src, length);
+        dst[length-1] = 0;
+    }
+}
+
 char *_Nullable BSGCStringWithData(NSData *_Nullable data) {
     char *buffer;
     if (data.length && (buffer = calloc(1, data.length + 1))) {

CHANGELOG.md

@@ -1,6 +1,14 @@
 Changelog
 =========
 
+## TBD
+
+### Bug fixes
+
+* Check app version to avoid detecting an app upgrade as an OOM
+  [1597](https://github.com/bugsnag/bugsnag-cocoa/pull/1597)
+
+
 ## 6.27.2 (2023-07-24)
 
 ### Enhancements

Tests/BugsnagTests/BSGOutOfMemoryTests.m

@@ -133,6 +133,9 @@ - (void)testLastLaunchTerminatedUnexpectedly {
     XCTAssertFalse(BSGRunContextWasKilled());
     uuid_copy(lastRunContext.machoUUID, bsg_runContext->machoUUID);
 
+    strncpy(lastRunContext.bundleVersion, "999.99", sizeof(lastRunContext.bundleVersion));
+    XCTAssertFalse(BSGRunContextWasKilled());
+
     lastRunContext.bootTime = 0;
     XCTAssertFalse(BSGRunContextWasKilled());
     lastRunContext.bootTime = bsg_runContext->bootTime;