| Message ID | 325102b3-eaa8-4918-a947-22aca1146586@stanley.mountain |
|---|---|
| State | New |
| Headers | show |
| Series | usb: typec: fix potential out of bounds in ucsi_ccg_update_set_new_cam_cmd() | expand |
diff --git a/drivers/usb/typec/ucsi/ucsi_ccg.c b/drivers/usb/typec/ucsi/ucsi_ccg.c index ba58d11907bc..bccfc03b5986 100644 --- a/drivers/usb/typec/ucsi/ucsi_ccg.c +++ b/drivers/usb/typec/ucsi/ucsi_ccg.c @@ -482,6 +482,8 @@ static void ucsi_ccg_update_set_new_cam_cmd(struct ucsi_ccg *uc, port = uc->orig; new_cam = UCSI_SET_NEW_CAM_GET_AM(*cmd); + if (new_cam >= ARRAY_SIZE(uc->updated)) + return; new_port = &uc->updated[new_cam]; cam = new_port->linked_idx; enter_new_mode = UCSI_SET_NEW_CAM_ENTER(*cmd);
The "*cmd" variable can be controlled by the user via debugfs. That means "new_cam" can be as high as 255 while the size of the uc->updated[] array is UCSI_MAX_ALTMODES (30). The call tree is: ucsi_cmd() // val comes from simple_attr_write_xsigned() -> ucsi_send_command() -> ucsi_send_command_common() -> ucsi_run_command() // calls ucsi->ops->sync_control() -> ucsi_ccg_sync_control() Fixes: 170a6726d0e2 ("usb: typec: ucsi: add support for separate DP altmode devices") Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org> --- drivers/usb/typec/ucsi/ucsi_ccg.c | 2 ++ 1 file changed, 2 insertions(+)