This is a note to let you know that I've just added the patch titled usb: typec: fix potential array underflow in ucsi_ccg_sync_control() to the 6.12-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: usb-typec-fix-potential-array-underflow-in-ucsi_ccg_.patch and it can be found in the queue-6.12 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 47602c5dbef05a8b30176abbed85675c4a22d961 Author: Dan Carpenter <dan.carpenter@xxxxxxxxxx> Date: Mon Nov 11 14:08:06 2024 +0300 usb: typec: fix potential array underflow in ucsi_ccg_sync_control() [ Upstream commit e56aac6e5a25630645607b6856d4b2a17b2311a5 ] The "command" variable can be controlled by the user via debugfs. The worry is that if con_index is zero then "&uc->ucsi->connector[con_index - 1]" would be an array underflow. Fixes: 170a6726d0e2 ("usb: typec: ucsi: add support for separate DP altmode devices") Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx> Reviewed-by: Heikki Krogerus <heikki.krogerus@xxxxxxxxxxxxxxx> Link: https://lore.kernel.org/r/c69ef0b3-61b0-4dde-98dd-97b97f81d912@stanley.mountain Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/drivers/usb/typec/ucsi/ucsi_ccg.c b/drivers/usb/typec/ucsi/ucsi_ccg.c index bccfc03b5986d..fcb8e61136cfd 100644 --- a/drivers/usb/typec/ucsi/ucsi_ccg.c +++ b/drivers/usb/typec/ucsi/ucsi_ccg.c @@ -644,6 +644,10 @@ static int ucsi_ccg_sync_control(struct ucsi *ucsi, u64 command) uc->has_multiple_dp) { con_index = (uc->last_cmd_sent >> 16) & UCSI_CMD_CONNECTOR_MASK; + if (con_index == 0) { + ret = -EINVAL; + goto unlock; + } con = &uc->ucsi->connector[con_index - 1]; ucsi_ccg_update_set_new_cam_cmd(uc, con, &command); } @@ -651,6 +655,7 @@ static int ucsi_ccg_sync_control(struct ucsi *ucsi, u64 command) ret = ucsi_sync_control_common(ucsi, command); pm_runtime_put_sync(uc->dev); +unlock: mutex_unlock(&uc->lock); return ret;