diff options
| author | Oliver Hartkopp <socketcan@hartkopp.net> | 2022-11-02 10:54:31 +0100 |
|---|---|---|
| committer | Marc Kleine-Budde <mkl@pengutronix.de> | 2022-11-07 14:00:27 +0100 |
| commit | ae64438be1923e3c1102d90fd41db7afcfaf54cc (patch) | |
| tree | 4653f59a5d91825bee51259007370416134a0663 /include | |
| parent | 3eb3d283e8579a22b81dd2ac3987b77465b2a22f (diff) | |
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 <Dariusz.Stojaczyk@opensynergy.com>
Cc: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Cc: Max Staudt <max@enpas.org>
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Acked-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Link: https://lore.kernel.org/all/20221102095431.36831-1-socketcan@hartkopp.net
Cc: stable@vger.kernel.org # 6.0.x
[mkl: patch pch_can, too]
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Diffstat (limited to 'include')
| -rw-r--r-- | include/linux/can/dev.h | 16 |
1 files changed, 16 insertions, 0 deletions
diff --git a/include/linux/can/dev.h b/include/linux/can/dev.h index 58f5431a5559..982ba245eb41 100644 --- a/include/linux/can/dev.h +++ b/include/linux/can/dev.h @@ -152,6 +152,22 @@ static inline bool can_is_canxl_dev_mtu(unsigned int mtu) return (mtu >= CANXL_MIN_MTU && mtu <= CANXL_MAX_MTU); } +/* drop skb if it does not contain a valid CAN frame for sending */ +static inline bool can_dev_dropped_skb(struct net_device *dev, struct sk_buff *skb) +{ + struct can_priv *priv = netdev_priv(dev); + + if (priv->ctrlmode & CAN_CTRLMODE_LISTENONLY) { + netdev_info_once(dev, + "interface in listen only mode, dropping skb\n"); + kfree_skb(skb); + dev->stats.tx_dropped++; + return true; + } + + return can_dropped_invalid_skb(dev, skb); +} + void can_setup(struct net_device *dev); struct net_device *alloc_candev_mqs(int sizeof_priv, unsigned int echo_skb_max, |