[nrf fromtree] drivers: ieee802154: nrf5: drop packets that are too long

There was an observed situation where the assert checking frame length
is below 128 bytes was hit. While the nrf-802154 checks that the frame
does not exceed that size, there might exists code paths that allow such
packets to pass through.

The change removes the assert and drops the packet instead.
An error is also printed to allow for further debugging.

Signed-off-by: Rafał Kuźnia <[email protected]>
(cherry picked from commit 5925d71)

Author: e-rk

drivers/ieee802154/ieee802154_nrf5.c

@@ -179,7 +179,12 @@ static void nrf5_rx_thread(void *arg1, void *arg2, void *arg3)
 		}
 
 #if defined(CONFIG_NET_BUF_DATA_SIZE)
-		__ASSERT_NO_MSG(pkt_len <= CONFIG_NET_BUF_DATA_SIZE);
+		if (pkt_len > CONFIG_NET_BUF_DATA_SIZE) {
+			LOG_ERR("Received a frame exceeding the buffer size (%u): %u",
+				CONFIG_NET_BUF_DATA_SIZE, pkt_len);
+			LOG_HEXDUMP_ERR(rx_frame->psdu, rx_frame->psdu[0] + 1, "Received PSDU");
+			goto drop;
+		}
 #endif
 
 		LOG_DBG("Frame received");
@@ -232,7 +237,9 @@ static void nrf5_rx_thread(void *arg1, void *arg2, void *arg3)
 		rx_frame->psdu = NULL;
 		nrf_802154_buffer_free_raw(psdu);
 
-		net_pkt_unref(pkt);
+		if (pkt) {
+			net_pkt_unref(pkt);
+		}
 	}
 }