kernel/linux.git/drivers/net/can/dev.c, branch v5.9.12

can: dev: can_restart(): post buffer from the right context

2020-11-24T12:39:01+00:00

[ Upstream commit a1e654070a60d5d4f7cce59c38f4ca790bb79121 ] netif_rx() is meant to be called from interrupt contexts. can_restart() may be called by can_restart_work(), which is called from a worqueue, so it may run in process context. Use netif_rx_ni() instead. Fixes: 39549eef3587 ("can: CAN Network device driver and Netlink interface") Co-developed-by: Loris Fauster Signed-off-by: Loris Fauster Signed-off-by: Alejandro Concepcion Rodriguez Link: https://lore.kernel.org/r/4e84162b-fb31-3a73-fa9a-9438b4bd5234@acoro.eu [mkl: use netif_rx_ni() instead of netif_rx_any_context()] Signed-off-by: Marc Kleine-Budde Signed-off-by: Sasha Levin

can: dev: __can_get_echo_skb(): fix real payload length return value for RTR frames

2020-11-18T18:22:05+00:00

[ Upstream commit ed3320cec279407a86bc4c72edc4a39eb49165ec ] The can_get_echo_skb() function returns the number of received bytes to be used for netdev statistics. In the case of RTR frames we get a valid (potential non-zero) data length value which has to be passed for further operations. But on the wire RTR frames have no payload length. Therefore the value to be used in the statistics has to be zero for RTR frames. Reported-by: Vincent Mailhol Signed-off-by: Oliver Hartkopp Link: https://lore.kernel.org/r/20201020064443.80164-1-socketcan@hartkopp.net Fixes: cf5046b309b3 ("can: dev: let can_get_echo_skb() return dlc of CAN frame") Signed-off-by: Marc Kleine-Budde Signed-off-by: Sasha Levin

can: dev: can_get_echo_skb(): prevent call to kfree_skb() in hard IRQ context

2020-11-18T18:22:05+00:00

[ Upstream commit 2283f79b22684d2812e5c76fc2280aae00390365 ] If a driver calls can_get_echo_skb() during a hardware IRQ (which is often, but not always, the case), the 'WARN_ON(in_irq)' in net/core/skbuff.c#skb_release_head_state() might be triggered, under network congestion circumstances, together with the potential risk of a NULL pointer dereference. The root cause of this issue is the call to kfree_skb() instead of dev_kfree_skb_irq() in net/core/dev.c#enqueue_to_backlog(). This patch prevents the skb to be freed within the call to netif_rx() by incrementing its reference count with skb_get(). The skb is finally freed by one of the in-irq-context safe functions: dev_consume_skb_any() or dev_kfree_skb_any(). The "any" version is used because some drivers might call can_get_echo_skb() in a normal context. The reason for this issue to occur is that initially, in the core network stack, loopback skb were not supposed to be received in hardware IRQ context. The CAN stack is an exeption. This bug was previously reported back in 2017 in [1] but the proposed patch never got accepted. While [1] directly modifies net/core/dev.c, we try to propose here a smoother modification local to CAN network stack (the assumption behind is that only CAN devices are affected by this issue). [1] http://lore.kernel.org/r/57a3ffb6-3309-3ad5-5a34-e93c3fe3614d@cetitec.com Signed-off-by: Vincent Mailhol Link: https://lore.kernel.org/r/20201002154219.4887-2-mailhol.vincent@wanadoo.fr Fixes: 39549eef3587 ("can: CAN Network device driver and Netlink interface") Signed-off-by: Marc Kleine-Budde Signed-off-by: Sasha Levin

can: add missing attribute validation for termination

2020-03-03T21:28:48+00:00

Add missing attribute validation for IFLA_CAN_TERMINATION to the netlink policy. Fixes: 12a6075cabc0 ("can: dev: add CAN interface termination API") Signed-off-by: Jakub Kicinski Acked-by: Oliver Hartkopp Signed-off-by: David S. Miller

can: dev: can_restart(): remove unused code

2019-11-11T20:57:28+00:00

Value assigned to variable err is overwritten at line 562: err = priv->do_set_mode(dev, CAN_MODE_START); before it can be used. Also, notice that this code has been there since 2014. Addresses-Coverity-ID: 1227031 Signed-off-by: Gustavo A. R. Silva Signed-off-by: Marc Kleine-Budde

can: dev: add missing of_node_put() after calling of_get_child_by_name()

2019-11-04T20:47:20+00:00

of_node_put() needs to be called when the device node which is got from of_get_child_by_name() finished using. Fixes: 2290aefa2e90 ("can: dev: Add support for limiting configured bitrate") Cc: Franklin S Cooper Jr Signed-off-by: Wen Yang Cc: linux-stable Signed-off-by: Marc Kleine-Budde

Merge tag 'linux-can-next-for-5.4-20190904' of git://git.kernel.org/pub/scm/linux/kernel/git/mkl/linux-can-next

2019-09-05T10:17:50+00:00

Marc Kleine-Budde says: ==================== pull-request: can-next 2019-09-04 j1939 this is a pull request for net-next/master consisting of 21 patches. the first 12 patches are by me and target the CAN core infrastructure. They clean up the names of variables , structs and struct members, convert can_rx_register() to use max() instead of open coding it and remove unneeded code from the can_pernet_exit() callback. The next three patches are also by me and they introduce and make use of the CAN midlayer private structure. It is used to hold protocol specific per device data structures. The next patch is by Oleksij Rempel, switches the &net->can.rcvlists_lock from a spin_lock() to a spin_lock_bh(), so that it can be used from NAPI (soft IRQ) context. The next 4 patches are by Kurt Van Dijck, he first updates his email address via mailmap and then extends sockaddr_can to include j1939 members. The final patch is the collective effort of many entities (The j1939 authors: Oliver Hartkopp, Bastian Stender, Elenita Hinds, kbuild test robot, Kurt Van Dijck, Maxime Jayat, Robin van der Gracht, Oleksij Rempel, Marc Kleine-Budde). It adds support of SAE J1939 protocol to the CAN networking stack. SAE J1939 is the vehicle bus recommended practice used for communication and diagnostics among vehicle components. Originating in the car and heavy-duty truck industry in the United States, it is now widely used in other parts of the world. P.S.: This pull request doesn't invalidate my last pull request: "pull-request: can-next 2019-09-03". ==================== Signed-off-by: David S. Miller

can: make use of preallocated can_ml_priv for per device struct can_dev_rcv_lists

2019-09-04T11:29:15+00:00

This patch removes the old method of allocating the per device protocol specific memory via a netdevice_notifier. This had the drawback, that the allocation can fail, leading to a lot of null pointer checks in the code. This also makes the live cycle management of this memory quite complicated. This patch switches from the allocating the struct can_dev_rcv_lists in a NETDEV_REGISTER call to using the dev->ml_priv, which is allocated by the driver since the previous patch. Signed-off-by: Oleksij Rempel Acked-by: Oliver Hartkopp Signed-off-by: Marc Kleine-Budde

can: introduce CAN midlayer private and allocate it automatically

2019-09-04T11:29:14+00:00

This patch introduces the CAN midlayer private structure ("struct can_ml_priv") which should be used to hold protocol specific per device data structures. For now it's only member is "struct can_dev_rcv_lists". The CAN midlayer private is allocated via alloc_netdev()'s private and assigned to "struct net_device::ml_priv" during device creation. This is done transparently for CAN drivers using alloc_candev(). The slcan, vcan and vxcan drivers which are not using alloc_candev() have been adopted manually. The memory layout of the netdev_priv allocated via alloc_candev() will looke like this: +-------------------------+ | driver's priv | +-------------------------+ | struct can_ml_priv | +-------------------------+ | array of struct sk_buff | +-------------------------+ Signed-off-by: Oleksij Rempel Signed-off-by: Oliver Hartkopp Signed-off-by: Marc Kleine-Budde

can: dev: can_dev_init(): convert from printk(KERN_INFO) to pr_info

2019-09-03T08:28:13+00:00

This patch converts the printk(KERN_INFO) in can_dev_init() to pr_info(). Signed-off-by: Marc Kleine-Budde