From: Marc Kleine-Budde mkl@pengutronix.de
[ Upstream commit 4168d079aa41498639b2c64b4583375bcdf360d9 ]
A out of bounds access to "struct can_priv::echo_skb" leads to a kernel crash. Better print a sensible warning message instead and try to recover.
This patch is similar to:
| e7a6994d043a ("can: dev: __can_get_echo_skb(): Don't crash the kernel | if can_priv::echo_skb is accessed out of bounds")
Link: https://lore.kernel.org/r/20210319142700.305648-2-mkl@pengutronix.de 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 6a64fe410987..c3508109263e 100644 --- a/drivers/net/can/dev/skb.c +++ b/drivers/net/can/dev/skb.c @@ -151,7 +151,11 @@ void can_free_echo_skb(struct net_device *dev, unsigned int idx) { 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; + }
if (priv->echo_skb[idx]) { dev_kfree_skb_any(priv->echo_skb[idx]);