linux-stable.git/drivers/net/can/dev, branch v5.12.2

can: dev: Move device back to init netns on owning netns delete

2021-03-16T07:40:04+00:00

When a non-initial netns is destroyed, the usual policy is to delete
all virtual network interfaces contained, but move physical interfaces
back to the initial netns. This keeps the physical interface visible
on the system.

CAN devices are somewhat special, as they define rtnl_link_ops even
if they are physical devices. If a CAN interface is moved into a
non-initial netns, destroying that netns lets the interface vanish
instead of moving it back to the initial netns. default_device_exit()
skips CAN interfaces due to having rtnl_link_ops set. Reproducer:

  ip netns add foo
  ip link set can0 netns foo
  ip netns delete foo

WARNING: CPU: 1 PID: 84 at net/core/dev.c:11030 ops_exit_list+0x38/0x60
CPU: 1 PID: 84 Comm: kworker/u4:2 Not tainted 5.10.19 #1
Workqueue: netns cleanup_net
[] (unwind_backtrace) from [] (show_stack+0x10/0x14)
[] (show_stack) from [] (dump_stack+0x94/0xa8)
[] (dump_stack) from [] (__warn+0xb8/0x114)
[] (__warn) from [] (warn_slowpath_fmt+0x7c/0xac)
[] (warn_slowpath_fmt) from [] (ops_exit_list+0x38/0x60)
[] (ops_exit_list) from [] (cleanup_net+0x230/0x380)
[] (cleanup_net) from [] (process_one_work+0x1d8/0x438)
[] (process_one_work) from [] (worker_thread+0x64/0x5a8)
[] (worker_thread) from [] (kthread+0x148/0x14c)
[] (kthread) from [] (ret_from_fork+0x14/0x2c)

To properly restore physical CAN devices to the initial netns on owning
netns exit, introduce a flag on rtnl_link_ops that can be set by drivers.
For CAN devices setting this flag, default_device_exit() considers them
non-virtual, applying the usual namespace move.

The issue was introduced in the commit mentioned below, as at that time
CAN devices did not have a dellink() operation.

Fixes: e008b5fc8dc7 ("net: Simplfy default_device_exit and improve batching.")
Link: https://lore.kernel.org/r/20210302122423.872326-1-martin@strongswan.org
Signed-off-by: Martin Willi 
Signed-off-by: Marc Kleine-Budde

net: introduce CAN specific pointer in the struct net_device

2021-02-24T22:32:15+00:00

Since 20dd3850bcf8 ("can: Speed up CAN frame receiption by using
ml_priv") the CAN framework uses per device specific data in the AF_CAN
protocol. For this purpose the struct net_device->ml_priv is used. Later
the ml_priv usage in CAN was extended for other users, one of them being
CAN_J1939.

Later in the kernel ml_priv was converted to an union, used by other
drivers. E.g. the tun driver started storing it's stats pointer.

Since tun devices can claim to be a CAN device, CAN specific protocols
will wrongly interpret this pointer, which will cause system crashes.
Mostly this issue is visible in the CAN_J1939 stack.

To fix this issue, we request a dedicated CAN pointer within the
net_device struct.

Reported-by: syzbot+5138c4dd15a0401bec7b@syzkaller.appspotmail.com
Fixes: 20dd3850bcf8 ("can: Speed up CAN frame receiption by using ml_priv")
Fixes: ffd956eef69b ("can: introduce CAN midlayer private and allocate it automatically")
Fixes: 9d71dd0c7009 ("can: add support of SAE J1939 protocol")
Fixes: 497a5757ce4e ("tun: switch to net core provided statistics counters")
Signed-off-by: Oleksij Rempel 
Link: https://lore.kernel.org/r/20210223070127.4538-1-o.rempel@pengutronix.de
Signed-off-by: Jakub Kicinski

Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net

2021-01-29T01:09:31+00:00

drivers/net/can/dev.c
  b552766c872f ("can: dev: prevent potential information leak in can_fill_info()")
  3e77f70e7345 ("can: dev: move driver related infrastructure into separate subdir")
  0a042c6ec991 ("can: dev: move netlink related code into seperate file")

  Code move.

drivers/net/ethernet/mellanox/mlx5/core/en_ethtool.c
  57ac4a31c483 ("net/mlx5e: Correctly handle changing the number of queues when the interface is down")
  214baf22870c ("net/mlx5e: Support HTB offload")

  Adjacent code changes

net/switchdev/switchdev.c
  20776b465c0c ("net: switchdev: don't set port_obj_info->handled true when -EOPNOTSUPP")
  ffb68fc58e96 ("net: switchdev: remove the transaction structure from port object notifiers")
  bae33f2b5afe ("net: switchdev: remove the transaction structure from port attributes")

  Transaction parameter gets dropped otherwise keep the fix.

Signed-off-by: Jakub Kicinski

can: length: can_fd_len2dlc(): make legnth calculation readable again

2021-01-27T09:01:46+00:00

In commit 652562e5ff06 ("can: length: can_fd_len2dlc(): simplify length
calculcation") the readability of the code degraded and became more error
prone. To counteract this, partially convert that patch and replace open coded
values (of the original code) with proper defines.

Fixes: 652562e5ff06 ("can: length: can_fd_len2dlc(): simplify length calculcation")
Cc: Vincent MAILHOL 
Link: https://lore.kernel.org/r/20210118201346.79422-1-socketcan@hartkopp.net
Signed-off-by: Oliver Hartkopp 
Signed-off-by: Marc Kleine-Budde

can: dev: export can_get_state_str() function

2021-01-27T09:01:46+00:00

The can_get_state_str() function is also relevant to the drivers. Export the
symbol and make it visible in the can/dev.h header.

Link: https://lore.kernel.org/r/20210119170355.12040-1-mailhol.vincent@wanadoo.fr
Signed-off-by: Vincent Mailhol 
Signed-off-by: Marc Kleine-Budde

Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net

2021-01-20T20:16:11+00:00

Conflicts:

drivers/net/can/dev.c
  commit 03f16c5075b2 ("can: dev: can_restart: fix use after free bug")
  commit 3e77f70e7345 ("can: dev: move driver related infrastructure into separate subdir")

  Code move.

drivers/net/dsa/b53/b53_common.c
 commit 8e4052c32d6b ("net: dsa: b53: fix an off by one in checking "vlan->vid"")
 commit b7a9e0da2d1c ("net: switchdev: remove vid_begin -> vid_end range from VLAN objects")

 Field rename.

Signed-off-by: Jakub Kicinski

can: dev: can_put_echo_skb(): add software tx timestamps

2021-01-14T07:43:44+00:00

Call skb_tx_timestamp() within can_put_echo_skb() so that a software tx
timestamp gets attached to the skb.

There two main reasons to include this call in can_put_echo_skb():

  * It easily allow to enable the tx timestamp on all devices with
    just one small change.

  * According to Documentation/networking/timestamping.rst, the tx
    timestamps should be generated in the device driver as close as possible,
    but always prior to passing the packet to the network interface. During the
    call to can_put_echo_skb(), the skb gets cloned meaning that the driver
    should not dereference the skb variable anymore after can_put_echo_skb()
    returns. This makes can_put_echo_skb() the very last place we can use the
    skb without having to access the echo_skb[] array.

Remark: by default, skb_tx_timestamp() does nothing. It needs to be activated
by passing the SOF_TIMESTAMPING_TX_SOFTWARE flag either through socket options
or control messages.

References:

 * Support for the error queue in CAN RAW sockets (which is needed for
   tx timestamps) was introduced in:
   https://git.kernel.org//torvalds/c/eb88531bdbfaafb827192d1fc6c5a3fcc4fadd96

  * Put the call to skb_tx_timestamp() just before adding it to the
    array:
    https://lore.kernel.org/r/043c3ea1-6bdd-59c0-0269-27b2b5b36cec@victronenergy.com

  * About Tx hardware timestamps
    https://lore.kernel.org/r/20210111171152.GB11715@hoboy.vegasvil.org

Signed-off-by: Vincent Mailhol 
Link: https://lore.kernel.org/r/20210112095437.6488-2-mailhol.vincent@wanadoo.fr
Signed-off-by: Marc Kleine-Budde

can: dev: can_rx_offload_get_echo_skb(): extend to return can frame length

2021-01-14T07:43:43+00:00

In order to implement byte queue limits (bql) in CAN drivers, the length of the
CAN frame needs to be passed into the networking stack after queueing and after
transmission completion.

To avoid to calculate this length twice, extend can_rx_offload_get_echo_skb()
to return that value. Convert all users of this function, too.

Reviewed-by: Vincent Mailhol 
Link: https://lore.kernel.org/r/20210111141930.693847-15-mkl@pengutronix.de
Signed-off-by: Marc Kleine-Budde

can: dev: can_get_echo_skb(): extend to return can frame length

2021-01-14T07:43:43+00:00

In order to implement byte queue limits (bql) in CAN drivers, the length of the
CAN frame needs to be passed into the networking stack after queueing and after
transmission completion.

To avoid to calculate this length twice, extend can_get_echo_skb() to return
that value. Convert all users of this function, too.

Reviewed-by: Vincent Mailhol 
Link: https://lore.kernel.org/r/20210111141930.693847-14-mkl@pengutronix.de
Signed-off-by: Marc Kleine-Budde

can: dev: can_put_echo_skb(): extend to handle frame_len

2021-01-14T07:43:43+00:00

Add a frame_len argument to can_put_echo_skb() which is used to save length of
the CAN frame into field frame_len of struct can_skb_priv so that it can be
later used after transmission completion. Convert all users of this function,
too.

Drivers which implement BQL call can_put_echo_skb() with the output of
can_skb_get_frame_len(skb) and drivers which do not simply pass zero as an
input (in the same way that NULL would be given to can_get_echo_skb()). This
way, we have a nice symmetry between the two echo functions.

Link: https://lore.kernel.org/r/20210111061335.39983-1-mailhol.vincent@wanadoo.fr
Signed-off-by: Marc Kleine-Budde 
Reviewed-by: Vincent Mailhol 
Link: https://lore.kernel.org/r/20210111141930.693847-13-mkl@pengutronix.de
Signed-off-by: Vincent Mailhol