This is a note to let you know that I've just added the patch titled
can: dev: __can_get_echo_skb(): print error message, if trying to echo non existing skb
to the 4.14-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
can-dev-__can_get_echo_skb-print-error-message-if-trying-to-echo-non-existing-skb.patch
and it can be found in the queue-4.14 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 7da11ba5c5066dadc2e96835a6233d56d7b7764a Mon Sep 17 00:00:00 2001
From: Marc Kleine-Budde <mkl@xxxxxxxxxxxxxx>
Date: Wed, 31 Oct 2018 14:15:13 +0100
Subject: can: dev: __can_get_echo_skb(): print error message, if trying to echo non existing skb
From: Marc Kleine-Budde <mkl@xxxxxxxxxxxxxx>
commit 7da11ba5c5066dadc2e96835a6233d56d7b7764a upstream.
Prior to echoing a successfully transmitted CAN frame (by calling
can_get_echo_skb()), CAN drivers have to put the CAN frame (by calling
can_put_echo_skb() in the transmit function). These put and get function
take an index as parameter, which is used to identify the CAN frame.
A driver calling can_get_echo_skb() with a index not pointing to a skb
is a BUG, so add an appropriate error message.
Cc: linux-stable <stable@xxxxxxxxxxxxxxx>
Signed-off-by: Marc Kleine-Budde <mkl@xxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/net/can/dev.c | 27 ++++++++++++++-------------
1 file changed, 14 insertions(+), 13 deletions(-)
--- a/drivers/net/can/dev.c
+++ b/drivers/net/can/dev.c
@@ -479,6 +479,8 @@ EXPORT_SYMBOL_GPL(can_put_echo_skb);
struct sk_buff *__can_get_echo_skb(struct net_device *dev, unsigned int idx, u8 *len_ptr)
{
struct can_priv *priv = netdev_priv(dev);
+ struct sk_buff *skb = priv->echo_skb[idx];
+ struct canfd_frame *cf;
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",
@@ -486,21 +488,20 @@ struct sk_buff *__can_get_echo_skb(struc
return NULL;
}
- if (priv->echo_skb[idx]) {
- /* Using "struct canfd_frame::len" for the frame
- * length is supported on both CAN and CANFD frames.
- */
- struct sk_buff *skb = priv->echo_skb[idx];
- struct canfd_frame *cf = (struct canfd_frame *)skb->data;
- u8 len = cf->len;
-
- *len_ptr = len;
- priv->echo_skb[idx] = NULL;
-
- return skb;
+ if (!skb) {
+ netdev_err(dev, "%s: BUG! Trying to echo non existing skb: can_priv::echo_skb[%u]\n",
+ __func__, idx);
+ return NULL;
}
- return NULL;
+ /* Using "struct canfd_frame::len" for the frame
+ * length is supported on both CAN and CANFD frames.
+ */
+ cf = (struct canfd_frame *)skb->data;
+ *len_ptr = cf->len;
+ priv->echo_skb[idx] = NULL;
+
+ return skb;
}
/*
Patches currently in stable-queue which might be from mkl@xxxxxxxxxxxxxx are
queue-4.14/can-dev-__can_get_echo_skb-replace-struct-can_frame-by-canfd_frame-to-access-frame-length.patch
queue-4.14/can-flexcan-use-can_rx_offload_queue_sorted-for-flexcan_irq_bus_.patch
queue-4.14/can-rx-offload-introduce-can_rx_offload_get_echo_skb-and-can_rx_offload_queue_sorted-functions.patch
queue-4.14/can-dev-__can_get_echo_skb-don-t-crash-the-kernel-if-can_priv-echo_skb-is-accessed-out-of-bounds.patch
queue-4.14/can-raw-check-for-can-fd-capable-netdev-in-raw_sendmsg.patch
queue-4.14/can-rx-offload-rename-can_rx_offload_irq_queue_err_skb-to-can_rx_offload_queue_tail.patch
queue-4.14/can-dev-can_get_echo_skb-factor-out-non-sending-code-to-__can_get_echo_skb.patch
queue-4.14/can-flexcan-handle-tx-complete-can-frames-via-rx-offload-infrastructure.patch
queue-4.14/can-hi311x-use-level-triggered-interrupt.patch
queue-4.14/can-dev-__can_get_echo_skb-print-error-message-if-trying-to-echo-non-existing-skb.patch
