[PATCH 6.12 609/826] usb: typec: fix potential array underflow in ucsi_ccg_sync_control()

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



6.12-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Dan Carpenter <dan.carpenter@xxxxxxxxxx>

[ 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>
---
 drivers/usb/typec/ucsi/ucsi_ccg.c | 5 +++++
 1 file changed, 5 insertions(+)

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;
-- 
2.43.0







[Index of Archives]     [Linux Kernel]     [Kernel Development Newbies]     [Linux USB Devel]     [Video for Linux]     [Linux Audio Users]     [Yosemite Hiking]     [Linux Kernel]     [Linux SCSI]

  Powered by Linux