diff --git a/tools/testing/selftests/bpf/progs/test_sysctl_prog.c b/tools/testing/selftests/bpf/progs/test_sysctl_prog.c
index 5cbbff416998..4396faf33394 100644
--- a/tools/testing/selftests/bpf/progs/test_sysctl_prog.c
+++ b/tools/testing/selftests/bpf/progs/test_sysctl_prog.c
@@ -19,11 +19,11 @@
 #define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0]))
 #endif
 
+const char tcp_mem_name[] = "net/ipv4/tcp_mem";
 static __always_inline int is_tcp_mem(struct bpf_sysctl *ctx)
 {
-	char tcp_mem_name[] = "net/ipv4/tcp_mem";
 	unsigned char i;
-	char name[64];
+	char name[sizeof(tcp_mem_name)];
 	int ret;
 
 	memset(name, 0, sizeof(name));