Fix access violation when reporting fatal errors during startup (#121602)

jkotas · web-flow · commit 39d41387dbb5 · 2025-11-14T04:26:06.000Z
Fixes #121596
diff --git a/src/coreclr/vm/threads.cpp b/src/coreclr/vm/threads.cpp
@@ -6873,6 +6873,12 @@ BOOL ThreadStore::HoldingThreadStore(Thread *pThread)
     }
     CONTRACTL_END;
 
+    // This can be called early during startup from HandleFatalError
+    if (s_pThreadStore == NULL)
+    {
+        return FALSE;
+    }
+
     if (pThread)
     {
         return (pThread == s_pThreadStore->m_HoldingThread);

Original file line number	Diff line number	Diff line change
`@@ -6873,6 +6873,12 @@ BOOL ThreadStore::HoldingThreadStore(Thread *pThread)`
`6873`	`6873`	`}`
`6874`	`6874`	`CONTRACTL_END;`
`6875`	`6875`
	`6876`	`+ // This can be called early during startup from HandleFatalError`
	`6877`	`+ if (s_pThreadStore == NULL)`
	`6878`	`+ {`
	`6879`	`+ return FALSE;`
	`6880`	`+ }`
	`6881`	`+`
`6876`	`6882`	`if (pThread)`
`6877`	`6883`	`{`
`6878`	`6884`	`return (pThread == s_pThreadStore->m_HoldingThread);`