[PATCH net-next v2 6/6] net/lapb: fix t1 timer handling

From: Martin Schiller
Date: Mon Nov 16 2020 - 09:02:39 EST


fix t1 timer handling in LAPB_STATE_0:
o DTE interface changes immediately to LAPB_STATE_1 and start sending
SABM(E).
o DCE interface sends N2-times DM and changes to LAPB_STATE_1
afterwards if there is no response in the meantime.

Signed-off-by: Martin Schiller <ms@xxxxxxxxxx>
---

Change from v1:
fix 'subject_prefix' and 'checkpatch' warnings

---
net/lapb/lapb_timer.c | 11 +++++++++--
1 file changed, 9 insertions(+), 2 deletions(-)

diff --git a/net/lapb/lapb_timer.c b/net/lapb/lapb_timer.c
index 8f5b17001a07..baa247fe4ed0 100644
--- a/net/lapb/lapb_timer.c
+++ b/net/lapb/lapb_timer.c
@@ -85,11 +85,18 @@ static void lapb_t1timer_expiry(struct timer_list *t)
switch (lapb->state) {

/*
- * If we are a DCE, keep going DM .. DM .. DM
+ * If we are a DCE, send DM up to N2 times, then switch to
+ * STATE_1 and send SABM(E).
*/
case LAPB_STATE_0:
- if (lapb->mode & LAPB_DCE)
+ if (lapb->mode & LAPB_DCE &&
+ lapb->n2count != lapb->n2) {
+ lapb->n2count++;
lapb_send_control(lapb, LAPB_DM, LAPB_POLLOFF, LAPB_RESPONSE);
+ } else {
+ lapb->state = LAPB_STATE_1;
+ lapb_establish_data_link(lapb);
+ }
break;

/*
--
2.20.1