From: Chan Shu Tak, Alex <alexchan@xxxxxxxxxxx> [ Upstream commit af1c0e4e00f3cc76cb136ebf2e2c04e8b6446285 ] When a frame with NULL DSAP is received, llc_station_rcv is called. In turn, llc_stat_ev_rx_null_dsap_xid_c is called to check if it is a NULL XID frame. The return statement of llc_stat_ev_rx_null_dsap_xid_c returns 1 when the incoming frame is not a NULL XID frame and 0 otherwise. Hence, a NULL XID response is returned unexpectedly, e.g. when the incoming frame is a NULL TEST command. To fix the error, simply remove the conditional operator. A similar error in llc_stat_ev_rx_null_dsap_test_c is also fixed. Signed-off-by: Chan Shu Tak, Alex <alexchan@xxxxxxxxxxx> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- net/llc/llc_station.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) --- a/net/llc/llc_station.c +++ b/net/llc/llc_station.c @@ -32,7 +32,7 @@ static int llc_stat_ev_rx_null_dsap_xid_ return LLC_PDU_IS_CMD(pdu) && /* command PDU */ LLC_PDU_TYPE_IS_U(pdu) && /* U type PDU */ LLC_U_PDU_CMD(pdu) == LLC_1_PDU_CMD_XID && - !pdu->dsap ? 0 : 1; /* NULL DSAP value */ + !pdu->dsap; /* NULL DSAP value */ } static int llc_stat_ev_rx_null_dsap_test_c(struct sk_buff *skb) @@ -42,7 +42,7 @@ static int llc_stat_ev_rx_null_dsap_test return LLC_PDU_IS_CMD(pdu) && /* command PDU */ LLC_PDU_TYPE_IS_U(pdu) && /* U type PDU */ LLC_U_PDU_CMD(pdu) == LLC_1_PDU_CMD_TEST && - !pdu->dsap ? 0 : 1; /* NULL DSAP */ + !pdu->dsap; /* NULL DSAP */ } static int llc_station_ac_send_xid_r(struct sk_buff *skb)
