Update RSP with fault address for stack overflow (case 1148592)

Use actual stack fault address rather than relying on the
SP of the current frame. If we try to enter a method with a
large prolog (many locals) we may try to allocate more stack
than is available, however the SP has not been updated. This
means the stack overflow heuristic to free up enough space
may fail, as the used stack may be smaller than the amount
of stack that was attempted to be unwound.

Author: joncham

mono/mini/exceptions-amd64.c

@@ -151,6 +151,17 @@ LONG CALLBACK seh_vectored_exception_handler(EXCEPTION_POINTERS* ep)
 	switch (er->ExceptionCode) {
 	case EXCEPTION_STACK_OVERFLOW:
 		if (!mono_aot_only && restore_stack) {
+			if (er->NumberParameters == 2) {
+				/* Use actual stack fault address rather than relying on the
+				 * SP of the current frame. If we try to enter a method with a
+				 * large prolog (many locals) we may try to allocate more stack
+				 * than is available, however the SP has not been updated. This
+				 * means the stack overflow heuristic to free up enough space
+				 * may fail, as the used stack may be smaller than the amount
+				 * of stack that was attempted to be unwound.
+				 */
+				ctx->Rsp = er->ExceptionInformation[1]; /* FaultAddress */
+			}
 			if (mono_arch_handle_exception (ctx, domain->stack_overflow_ex)) {
 				/* need to restore stack protection once stack is unwound
 				 * restore_stack will restore stack protection and then