6.6-stable review patch. If anyone has any objections, please let me know.
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From: Marc Kleine-Budde mkl@pengutronix.de
[ Upstream commit 6411959c10fe917288cbb1038886999148560057 ]
If the "struct can_priv::echoo_skb" is accessed out of bounds, this would cause a kernel crash. Instead, issue a meaningful warning message and return with an error.
Fixes: a6e4bc530403 ("can: make the number of echo skb's configurable") Link: https://lore.kernel.org/all/20231005-can-dev-fix-can-restart-v2-5-91b5c1fd92... Reviewed-by: Vincent Mailhol mailhol.vincent@wanadoo.fr Signed-off-by: Marc Kleine-Budde mkl@pengutronix.de Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/net/can/dev/skb.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-)
diff --git a/drivers/net/can/dev/skb.c b/drivers/net/can/dev/skb.c index f6d05b3ef59ab..3ebd4f779b9bd 100644 --- a/drivers/net/can/dev/skb.c +++ b/drivers/net/can/dev/skb.c @@ -49,7 +49,11 @@ int can_put_echo_skb(struct sk_buff *skb, struct net_device *dev, { struct can_priv *priv = netdev_priv(dev);
- BUG_ON(idx >= priv->echo_skb_max); + if (idx >= priv->echo_skb_max) { + netdev_err(dev, "%s: BUG! Trying to access can_priv::echo_skb out of bounds (%u/max %u)\n", + __func__, idx, priv->echo_skb_max); + return -EINVAL; + }
/* check flag whether this packet has to be looped back */ if (!(dev->flags & IFF_ECHO) ||