diff --git a/lib/net_buf/buf.c b/lib/net_buf/buf.c
index cce0fc8d5442f..c8290aa5534fa 100644
--- a/lib/net_buf/buf.c
+++ b/lib/net_buf/buf.c
@@ -34,8 +34,6 @@ LOG_MODULE_REGISTER(LOG_MODULE_NAME);
 #define NET_BUF_INFO(fmt, ...)
 #endif /* CONFIG_NET_BUF_LOG */
 
-#define NET_BUF_ASSERT(cond, ...) __ASSERT(cond, "" __VA_ARGS__)
-
 #if CONFIG_NET_BUF_WARN_ALLOC_INTERVAL > 0
 #define WARN_ALLOC_INTERVAL K_SECONDS(CONFIG_NET_BUF_WARN_ALLOC_INTERVAL)
 #else
@@ -331,9 +329,8 @@ struct net_buf *net_buf_alloc_len(struct net_buf_pool *pool, size_t size,
 	NET_BUF_DBG("allocated buf %p", buf);
 
 	if (size) {
-#if __ASSERT_ON
-		size_t req_size = size;
-#endif
+		__maybe_unused size_t req_size = size;
+
 		timeout = sys_timepoint_timeout(end);
 		buf->__buf = data_alloc(buf, &size, timeout);
 		if (!buf->__buf) {
@@ -343,9 +340,7 @@ struct net_buf *net_buf_alloc_len(struct net_buf_pool *pool, size_t size,
 			return NULL;
 		}
 
-#if __ASSERT_ON
-		NET_BUF_ASSERT(req_size <= size);
-#endif
+		__ASSERT_NO_MSG(req_size <= size);
 	} else {
 		buf->__buf = NULL;
 	}
@@ -452,13 +447,14 @@ void net_buf_unref(struct net_buf *buf)
 		struct net_buf *frags = buf->frags;
 		struct net_buf_pool *pool;
 
-#if defined(CONFIG_NET_BUF_LOG)
+		__ASSERT(buf->ref, "buf %p double free", buf);
 		if (!buf->ref) {
+#if defined(CONFIG_NET_BUF_LOG)
 			NET_BUF_ERR("%s():%d: buf %p double free", func, line,
 				    buf);
+#endif
 			return;
 		}
-#endif
 		NET_BUF_DBG("buf %p ref %u pool_id %u frags %p", buf, buf->ref,
 			    buf->pool_id, buf->frags);
 
diff --git a/tests/drivers/udc/src/main.c b/tests/drivers/udc/src/main.c
index e08a8f615a15b..716f41440d2fb 100644
--- a/tests/drivers/udc/src/main.c
+++ b/tests/drivers/udc/src/main.c
@@ -576,7 +576,6 @@ ZTEST(udc_driver_test, test_udc_enabled)
 	test_udc_ep_halt(dev, &ed_bulk_out);
 	test_udc_ep_disable(dev, &ed_bulk_out);
 	test_udc_ep_dequeue(dev, &ed_bulk_out);
-	test_udc_ep_buf_free(dev, buf);
 
 	err = udc_shutdown(dev);
 	zassert_equal(err, -EBUSY, "Not failed to shoot-down UDC driver");
diff --git a/tests/lib/net_buf/buf/prj.conf b/tests/lib/net_buf/buf/prj.conf
index 47e462402b35a..595e36061816e 100644
--- a/tests/lib/net_buf/buf/prj.conf
+++ b/tests/lib/net_buf/buf/prj.conf
@@ -1,5 +1,4 @@
 CONFIG_NET_BUF=y
-CONFIG_NET_TEST=y
 CONFIG_HEAP_MEM_POOL_SIZE=4096
 #CONFIG_NET_BUF_LOG=y
 #CONFIG_NET_BUF_LOG_LEVEL_DBG=y
diff --git a/tests/lib/net_buf/buf/src/main.c b/tests/lib/net_buf/buf/src/main.c
index 4ef90295e8541..0d9f679408704 100644
--- a/tests/lib/net_buf/buf/src/main.c
+++ b/tests/lib/net_buf/buf/src/main.c
@@ -288,7 +288,6 @@ ZTEST(net_buf_tests, test_net_buf_4)
 
 		if ((i % 2) && next) {
 			net_buf_frag_del(frag, next);
-			net_buf_unref(next);
 			removed++;
 		} else {
 			frag = next;
@@ -312,7 +311,6 @@ ZTEST(net_buf_tests, test_net_buf_4)
 		struct net_buf *frag2 = buf->frags;
 
 		net_buf_frag_del(buf, frag2);
-		net_buf_unref(frag2);
 		removed++;
 	}