This is a note to let you know that I've just added the patch titled Bluetooth: hci_conn: Fix crash on hci_create_cis_sync to the 6.1-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: bluetooth-hci_conn-fix-crash-on-hci_create_cis_sync.patch and it can be found in the queue-6.1 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit f82977a675f5434b172626b266050e2b51c04594 Author: Luiz Augusto von Dentz <luiz.von.dentz@xxxxxxxxx> Date: Mon Dec 5 17:11:57 2022 -0800 Bluetooth: hci_conn: Fix crash on hci_create_cis_sync [ Upstream commit 50757a259ba78c4e938b5735e76ffec6cd0c942e ] When attempting to connect multiple ISO sockets without using DEFER_SETUP may result in the following crash: BUG: KASAN: null-ptr-deref in hci_create_cis_sync+0x18b/0x2b0 Read of size 2 at addr 0000000000000036 by task kworker/u3:1/50 CPU: 0 PID: 50 Comm: kworker/u3:1 Not tainted 6.0.0-rc7-02243-gb84a13ff4eda #4373 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.0-1.fc36 04/01/2014 Workqueue: hci0 hci_cmd_sync_work Call Trace: <TASK> dump_stack_lvl+0x19/0x27 kasan_report+0xbc/0xf0 ? hci_create_cis_sync+0x18b/0x2b0 hci_create_cis_sync+0x18b/0x2b0 ? get_link_mode+0xd0/0xd0 ? __ww_mutex_lock_slowpath+0x10/0x10 ? mutex_lock+0xe0/0xe0 ? get_link_mode+0xd0/0xd0 hci_cmd_sync_work+0x111/0x190 process_one_work+0x427/0x650 worker_thread+0x87/0x750 ? process_one_work+0x650/0x650 kthread+0x14e/0x180 ? kthread_exit+0x50/0x50 ret_from_fork+0x22/0x30 </TASK> Fixes: 26afbd826ee3 ("Bluetooth: Add initial implementation of CIS connections") Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@xxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/net/bluetooth/hci_conn.c b/net/bluetooth/hci_conn.c index a6c12863a253..8aab2e882958 100644 --- a/net/bluetooth/hci_conn.c +++ b/net/bluetooth/hci_conn.c @@ -1881,7 +1881,7 @@ static int hci_create_cis_sync(struct hci_dev *hdev, void *data) continue; /* Check if all CIS(s) belonging to a CIG are ready */ - if (conn->link->state != BT_CONNECTED || + if (!conn->link || conn->link->state != BT_CONNECTED || conn->state != BT_CONNECT) { cmd.cp.num_cis = 0; break;