diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c
index 36a957c996c763d0d936fbf2c9e5afd0ac11853f..b49c107f82acbd0cc636838dd2e70a1e59eb1f71 100644
--- a/kernel/trace/trace_events.c
+++ b/kernel/trace/trace_events.c
@@ -1760,6 +1760,8 @@ static void update_event_printk(struct ftrace_event_call *call,
 				ptr++;
 				/* Check for alpha chars like ULL */
 			} while (isalnum(*ptr));
+			if (!*ptr)
+				break;
 			/*
 			 * A number must have some kind of delimiter after
 			 * it, and we can ignore that too.
@@ -1786,12 +1788,16 @@ static void update_event_printk(struct ftrace_event_call *call,
 			do {
 				ptr++;
 			} while (isalnum(*ptr) || *ptr == '_');
+			if (!*ptr)
+				break;
 			/*
 			 * If what comes after this variable is a '.' or
 			 * '->' then we can continue to ignore that string.
 			 */
 			if (*ptr == '.' || (ptr[0] == '-' && ptr[1] == '>')) {
 				ptr += *ptr == '.' ? 1 : 2;
+				if (!*ptr)
+					break;
 				goto skip_more;
 			}
 			/*