This is a note to let you know that I've just added the patch titled
tty: n_gsm: require CAP_NET_ADMIN to attach N_GSM0710 ldisc
to the 4.19-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:
tty-n_gsm-require-cap_net_admin-to-attach-n_gsm0710-ldisc.patch
and it can be found in the queue-4.19 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 67c37756898a5a6b2941a13ae7260c89b54e0d88 Mon Sep 17 00:00:00 2001
From: Thadeu Lima de Souza Cascardo <cascardo@xxxxxxxxxxxxx>
Date: Mon, 31 Jul 2023 15:59:42 -0300
Subject: tty: n_gsm: require CAP_NET_ADMIN to attach N_GSM0710 ldisc
From: Thadeu Lima de Souza Cascardo <cascardo@xxxxxxxxxxxxx>
commit 67c37756898a5a6b2941a13ae7260c89b54e0d88 upstream.
Any unprivileged user can attach N_GSM0710 ldisc, but it requires
CAP_NET_ADMIN to create a GSM network anyway.
Require initial namespace CAP_NET_ADMIN to do that.
Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@xxxxxxxxxxxxx>
Link: https://lore.kernel.org/r/20230731185942.279611-1-cascardo@xxxxxxxxxxxxx
From: Salvatore Bonaccorso <carnil@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/tty/n_gsm.c | 3 +++
1 file changed, 3 insertions(+)
--- a/drivers/tty/n_gsm.c
+++ b/drivers/tty/n_gsm.c
@@ -2435,6 +2435,9 @@ static int gsmld_open(struct tty_struct
struct gsm_mux *gsm;
int ret;
+ if (!capable(CAP_NET_ADMIN))
+ return -EPERM;
+
if (tty->ops->write == NULL)
return -EINVAL;
Patches currently in stable-queue which might be from cascardo@xxxxxxxxxxxxx are
queue-4.19/tty-n_gsm-require-cap_net_admin-to-attach-n_gsm0710-ldisc.patch
