Fix GH-14475: PHP 8.3.7 with JIT encounters infinite loop on specific paths (#14558)

Author: dstogov

ext/opcache/jit/zend_jit_trace.c

@@ -8308,7 +8308,20 @@ int ZEND_FASTCALL zend_jit_trace_exit(uint32_t exit_num, zend_jit_registers_buf
 		if (!(ZEND_OP_TRACE_INFO(t->opline, jit_extension->offset)->trace_flags & (ZEND_JIT_TRACE_JITED|ZEND_JIT_TRACE_BLACKLISTED))) {
 			/* skip: not JIT-ed nor blacklisted */
 		} else if (ZEND_JIT_TRACE_NUM >= JIT_G(max_root_traces)) {
-			/* skip: too many root traces */
+			/* too many root traces, blacklist the root trace */
+			if (!(ZEND_OP_TRACE_INFO(t->opline, jit_extension->offset)->trace_flags & ZEND_JIT_TRACE_BLACKLISTED)) {
+				SHM_UNPROTECT();
+				zend_jit_unprotect();
+
+				((zend_op*)opline)->handler =
+					ZEND_OP_TRACE_INFO(t->opline, jit_extension->offset)->orig_handler;
+
+				ZEND_OP_TRACE_INFO(t->opline, jit_extension->offset)->trace_flags &= ~ZEND_JIT_TRACE_JITED;
+				ZEND_OP_TRACE_INFO(t->opline, jit_extension->offset)->trace_flags |= ZEND_JIT_TRACE_BLACKLISTED;
+
+				zend_jit_protect();
+				SHM_PROTECT();
+			}
 		} else {
 			SHM_UNPROTECT();
 			zend_jit_unprotect();