linux-kernel - [PATCH v5 05/10] tty: n_gsm: increase malformed counter for malformed control frames

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Wed, 17 May 2023 17:56:59 +0200
From:   "D. Starke" <daniel.starke@...mens.com>
To:     linux-serial@...r.kernel.org, gregkh@...uxfoundation.org,
        jirislaby@...nel.org, ilpo.jarvinen@...ux.intel.com,
        felix-haase@...mens.com
Cc:     linux-kernel@...r.kernel.org,
        Daniel Starke <daniel.starke@...mens.com>
Subject: [PATCH v5 05/10] tty: n_gsm: increase malformed counter for malformed control frames

From: Daniel Starke <daniel.starke@...mens.com>

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@...mens.com>
---
 drivers/tty/n_gsm.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

v4 -> v5:
No changes.

Please note that I cannot response to emails until August 7th. Felix Haase
will take over from our side for questions regarding this patch series or
the n_gsm.

Link: https://lore.kernel.org/all/20230426080315.7595-5-daniel.starke@siemens.com/

diff --git a/drivers/tty/n_gsm.c b/drivers/tty/n_gsm.c
index 186f463f0f11..5b6a03668c78 100644
--- a/drivers/tty/n_gsm.c
+++ b/drivers/tty/n_gsm.c
@@ -2455,8 +2455,10 @@ 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