diff --git a/kernel/bpf/helpers.c b/kernel/bpf/helpers.c
index 2a69a9a36c0f..5bd5d6d6c8de 100644
--- a/kernel/bpf/helpers.c
+++ b/kernel/bpf/helpers.c
@@ -826,6 +826,9 @@ int bpf_bprintf_prepare(char *fmt, u32 fmt_size, const u64 *raw_args,
 	u64 cur_arg;
 	char fmt_ptype, cur_ip[16], ip_spec[] = "%pXX";
 
+	if (!fmt)
+		return -EINVAL;
+
 	fmt_end = strnchr(fmt, fmt_size, 0);
 	if (!fmt_end)
 		return -EINVAL;