5.10-stable review patch. If anyone has any objections, please let me know.
------------------
From: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
commit 7dd08a0b4193087976db6b3ee7807de7e8316f96 upstream.
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")
Cc: stable <stable@xxxxxxxxxx>
Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
Reviewed-by: Heikki Krogerus <heikki.krogerus@xxxxxxxxxxxxxxx>
Link: https://lore.kernel.org/r/325102b3-eaa8-4918-a947-22aca1146586@stanley.mountain
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/usb/typec/ucsi/ucsi_ccg.c | 2 ++
1 file changed, 2 insertions(+)
--- a/drivers/usb/typec/ucsi/ucsi_ccg.c
+++ b/drivers/usb/typec/ucsi/ucsi_ccg.c
@@ -436,6 +436,8 @@ static void ucsi_ccg_update_set_new_cam_
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);
