This is a note to let you know that I've just added the patch titled
llc2: Fix return statement of llc_stat_ev_rx_null_dsap_xid_c (and _test_c)
to the 4.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
llc2-fix-return-statement-of-llc_stat_ev_rx_null_dsa.patch
and it can be found in the queue-4.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit ae512cadc1be4056f9cd27e1b2fea81e3ef1df96
Author: Chan Shu Tak, Alex <alexchan@xxxxxxxxxxx>
Date: Thu Dec 19 14:16:18 2019 +0800
llc2: Fix return statement of llc_stat_ev_rx_null_dsap_xid_c (and _test_c)
[ 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>
diff --git a/net/llc/llc_station.c b/net/llc/llc_station.c
index 204a8351efff..c29170e767a8 100644
--- 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_c(struct sk_buff *skb)
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_c(struct sk_buff *skb)
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)
