[PATCH] Bluetooth: hci_ldisc: require CAP_NET_ADMIN to attach N_HCI ldisc

[PATCH] Bluetooth: hci_ldisc: require CAP_NET_ADMIN to attach N_HCI ldisc

[Thadeu Lima de Souza Cascardo]

Any unprivileged user can attach N_HCI ldisc and send packets coming from a
virtual controller by using PTYs.

Require initial namespace CAP_NET_ADMIN to do that.

Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com>
---
 drivers/bluetooth/hci_ldisc.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/bluetooth/hci_ldisc.c b/drivers/bluetooth/hci_ldisc.c
index 5ed2cfa7da1d..5e32e4d5367a 100644
--- a/drivers/bluetooth/hci_ldisc.c
+++ b/drivers/bluetooth/hci_ldisc.c
@@ -479,6 +479,9 @@ static int hci_uart_tty_open(struct tty_struct *tty)
 
 	BT_DBG("tty %p", tty);
 
+	if (!capable(CAP_NET_ADMIN))
+		return -EPERM;
+
 	/* Error if the tty has no write op instead of leaving an exploitable
 	 * hole
 	 */
-- 
2.30.2

RE: Bluetooth: hci_ldisc: require CAP_NET_ADMIN to attach N_HCI ldisc

[bluez.test.bot]

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This is automated email and please do not reply to this email!

Dear submitter,

Thank you for submitting the patches to the linux bluetooth mailing list.
This is a CI test results with your patch series:
PW Link:https://patchwork.kernel.org/project/bluetooth/list/?series=550945

---Test result---

Test Summary:
CheckPatch                    PASS      1.57 seconds
GitLint                       FAIL      0.94 seconds
BuildKernel                   PASS      666.33 seconds
TestRunner: Setup             PASS      433.65 seconds
TestRunner: l2cap-tester      PASS      3.49 seconds
TestRunner: bnep-tester       PASS      2.61 seconds
TestRunner: mgmt-tester       PASS      34.14 seconds
TestRunner: rfcomm-tester     PASS      2.83 seconds
TestRunner: smp-tester        PASS      2.92 seconds
TestRunner: userchan-tester   PASS      2.66 seconds

Details
##############################
Test: GitLint - FAIL - 0.94 seconds
Run gitlint with rule in .gitlint
Bluetooth: hci_ldisc: require CAP_NET_ADMIN to attach N_HCI ldisc
2: B4 Second line is not empty: "virtual controller by using PTYs."




---
Regards,
Linux Bluetooth


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Re: [PATCH] Bluetooth: hci_ldisc: require CAP_NET_ADMIN to attach N_HCI ldisc

[Marcel Holtmann]

Hi Thadeu,

> Any unprivileged user can attach N_HCI ldisc and send packets coming from a
> virtual controller by using PTYs.
> 
> Require initial namespace CAP_NET_ADMIN to do that.
> 
> Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com>
> ---
> drivers/bluetooth/hci_ldisc.c | 3 +++
> 1 file changed, 3 insertions(+)

patch has been applied to bluetooth-next tree.

Regards

Marcel