tty/n_gsm: fix a bug in gsm_dlci_data_output (adaption = 2 case)
in adaption=2 case we should put 1 or 2 byte with modem status bits
at the beginning of a buffer pointed by "dp". n_gsm use 1 byte case,
so it allocate a buffer of len + 1 size. As result we should:
* put 1 byte of modem status bits
* increase data pointer
* put "len" bytes of data
but actually we have:
* increase first byte with the value of modem status bits
* decrease "len"
* put orig_len - 1 bytes of data starting from the buffer beggining
This is evidently wrong.
Signed-off-by: Mikhail Kshevetskiy <mikhail.kshevetskiy@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
diff --git a/drivers/tty/n_gsm.c b/drivers/tty/n_gsm.c
index da3b31a..14c26cd 100644
--- a/drivers/tty/n_gsm.c
+++ b/drivers/tty/n_gsm.c
@@ -833,8 +833,7 @@
break;
case 2: /* Unstructed with modem bits. Always one byte as we never
send inline break data */
- *dp += gsm_encode_modem(dlci);
- len--;
+ *dp++ = gsm_encode_modem(dlci);
break;
}
WARN_ON(kfifo_out_locked(dlci->fifo, dp , len, &dlci->lock) != len);