From af4db5a35a4ef7a68046883bfd12468007db38f1 Mon Sep 17 00:00:00 2001 From: RD Babiera Date: Wed, 18 Jun 2025 22:49:42 +0000 Subject: usb: typec: altmodes/displayport: do not index invalid pin_assignments A poorly implemented DisplayPort Alt Mode port partner can indicate that its pin assignment capabilities are greater than the maximum value, DP_PIN_ASSIGN_F. In this case, calls to pin_assignment_show will cause a BRK exception due to an out of bounds array access. Prevent for loop in pin_assignment_show from accessing invalid values in pin_assignments by adding DP_PIN_ASSIGN_MAX value in typec_dp.h and using i < DP_PIN_ASSIGN_MAX as a loop condition. Fixes: 0e3bb7d6894d ("usb: typec: Add driver for DisplayPort alternate mode") Cc: stable Signed-off-by: RD Babiera Reviewed-by: Badhri Jagan Sridharan Reviewed-by: Heikki Krogerus Link: https://lore.kernel.org/r/20250618224943.3263103-2-rdbabiera@google.com Signed-off-by: Greg Kroah-Hartman --- include/linux/usb/typec_dp.h | 1 + 1 file changed, 1 insertion(+) (limited to 'include/linux') diff --git a/include/linux/usb/typec_dp.h b/include/linux/usb/typec_dp.h index f2da264d9c14..acb0ad03bdac 100644 --- a/include/linux/usb/typec_dp.h +++ b/include/linux/usb/typec_dp.h @@ -57,6 +57,7 @@ enum { DP_PIN_ASSIGN_D, DP_PIN_ASSIGN_E, DP_PIN_ASSIGN_F, /* Not supported after v1.0b */ + DP_PIN_ASSIGN_MAX, }; /* DisplayPort alt mode specific commands */ -- cgit v1.2.3