[PATCH v2 6/9] tty: n_gsm: increase malformed counter for malformed control frames

From: D. Starke
Date: Thu Apr 20 2023 - 04:54:58 EST


From: Daniel Starke <daniel.starke@xxxxxxxxxxx>

The malformed counter in gsm_mux is already increased in case of errors
detected in gsm_queue() and gsm1_receive(). gsm_dlci_command() also
detects a case for a malformed frame but does not increase the malformed
counter yet.

Fix this by also increasing the gsm_mux malformed counter in case of a
malformed frame in gsm_dlci_command().
Note that the malformed counter is not yet exposed and only set internally.

Signed-off-by: Daniel Starke <daniel.starke@xxxxxxxxxxx>
---
drivers/tty/n_gsm.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)

v1 -> v2:
Added remark to the commit message that the malformed counter is not yet
exposed to the user. This was remarked in the review.

Link: https://lore.kernel.org/all/AS4PR10MB589597931E257D7CACB984BCE0919@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx/

diff --git a/drivers/tty/n_gsm.c b/drivers/tty/n_gsm.c
index 1e97a41e6be9..cc7be05c37ce 100644
--- a/drivers/tty/n_gsm.c
+++ b/drivers/tty/n_gsm.c
@@ -2454,8 +2454,10 @@ static void gsm_dlci_command(struct gsm_dlci *dlci, const u8 *data, int len)
data += dlen;

/* Malformed command? */
- if (clen > len)
+ if (clen > len) {
+ dlci->gsm->malformed++;
return;
+ }

if (command & 1)
gsm_control_message(dlci->gsm, command, data, clen);
--
2.34.1