can: dev: fix skb drop check

In commit a6d190f8c767 ("can: skb: drop tx skb if in listen only
mode") the priv->ctrlmode element is read even on virtual CAN
interfaces that do not create the struct can_priv at startup. This
out-of-bounds read may lead to CAN frame drops for virtual CAN
interfaces like vcan and vxcan.

This patch mainly reverts the original commit and adds a new helper
for CAN interface drivers that provide the required information in
struct can_priv.

Fixes: a6d190f8c767 ("can: skb: drop tx skb if in listen only mode")
Reported-by: Dariusz Stojaczyk <[email protected]>
Cc: Vincent Mailhol <[email protected]>
Cc: Max Staudt <[email protected]>
Signed-off-by: Oliver Hartkopp <[email protected]>
Acked-by: Vincent Mailhol <[email protected]>
Link: https://lore.kernel.org/all/[email protected]
Cc: [email protected] # 6.0.x
[mkl: patch pch_can, too]
Signed-off-by: Marc Kleine-Budde <[email protected]>

0 files changed, 0 insertions, 0 deletions