Commit Graph

19 Commits

Author SHA1 Message Date
Martin Willi 3a5ca85707 can: dev: Move device back to init netns on owning netns delete
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
[<c010e700>] (unwind_backtrace) from [<c010a1d8>] (show_stack+0x10/0x14)
[<c010a1d8>] (show_stack) from [<c086dc10>] (dump_stack+0x94/0xa8)
[<c086dc10>] (dump_stack) from [<c086b938>] (__warn+0xb8/0x114)
[<c086b938>] (__warn) from [<c086ba10>] (warn_slowpath_fmt+0x7c/0xac)
[<c086ba10>] (warn_slowpath_fmt) from [<c0629f20>] (ops_exit_list+0x38/0x60)
[<c0629f20>] (ops_exit_list) from [<c062a5c4>] (cleanup_net+0x230/0x380)
[<c062a5c4>] (cleanup_net) from [<c0142c20>] (process_one_work+0x1d8/0x438)
[<c0142c20>] (process_one_work) from [<c0142ee4>] (worker_thread+0x64/0x5a8)
[<c0142ee4>] (worker_thread) from [<c0148a98>] (kthread+0x148/0x14c)
[<c0148a98>] (kthread) from [<c0100148>] (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: e008b5fc8d ("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 <martin@strongswan.org>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2021-03-16 08:40:04 +01:00
Oleksij Rempel 4e096a1886 net: introduce CAN specific pointer in the struct net_device
Since 20dd3850bc ("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: 20dd3850bc ("can: Speed up CAN frame receiption by using ml_priv")
Fixes: ffd956eef6 ("can: introduce CAN midlayer private and allocate it automatically")
Fixes: 9d71dd0c70 ("can: add support of SAE J1939 protocol")
Fixes: 497a5757ce ("tun: switch to net core provided statistics counters")
Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de>
Link: https://lore.kernel.org/r/20210223070127.4538-1-o.rempel@pengutronix.de
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-02-24 14:32:15 -08:00
Jakub Kicinski c358f95205 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
drivers/net/can/dev.c
  b552766c87 ("can: dev: prevent potential information leak in can_fill_info()")
  3e77f70e73 ("can: dev: move driver related infrastructure into separate subdir")
  0a042c6ec9 ("can: dev: move netlink related code into seperate file")

  Code move.

drivers/net/ethernet/mellanox/mlx5/core/en_ethtool.c
  57ac4a31c4 ("net/mlx5e: Correctly handle changing the number of queues when the interface is down")
  214baf2287 ("net/mlx5e: Support HTB offload")

  Adjacent code changes

net/switchdev/switchdev.c
  20776b465c ("net: switchdev: don't set port_obj_info->handled true when -EOPNOTSUPP")
  ffb68fc58e ("net: switchdev: remove the transaction structure from port object notifiers")
  bae33f2b5a ("net: switchdev: remove the transaction structure from port attributes")

  Transaction parameter gets dropped otherwise keep the fix.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-01-28 17:09:31 -08:00
Marc Kleine-Budde 54eca60b1c can: length: can_fd_len2dlc(): make legnth calculation readable again
In commit 652562e5ff ("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: 652562e5ff ("can: length: can_fd_len2dlc(): simplify length calculcation")
Cc: Vincent MAILHOL <mailhol.vincent@wanadoo.fr>
Link: https://lore.kernel.org/r/20210118201346.79422-1-socketcan@hartkopp.net
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2021-01-27 10:01:46 +01:00
Vincent Mailhol 6fe27d68b4 can: dev: export can_get_state_str() function
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 <mailhol.vincent@wanadoo.fr>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2021-01-27 10:01:46 +01:00
Jakub Kicinski 0fe2f273ab Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Conflicts:

drivers/net/can/dev.c
  commit 03f16c5075 ("can: dev: can_restart: fix use after free bug")
  commit 3e77f70e73 ("can: dev: move driver related infrastructure into separate subdir")

  Code move.

drivers/net/dsa/b53/b53_common.c
 commit 8e4052c32d ("net: dsa: b53: fix an off by one in checking "vlan->vid"")
 commit b7a9e0da2d ("net: switchdev: remove vid_begin -> vid_end range from VLAN objects")

 Field rename.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-01-20 12:16:11 -08:00
Vincent Mailhol 741b91f1b0 can: dev: can_put_echo_skb(): add software tx timestamps
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 <mailhol.vincent@wanadoo.fr>
Link: https://lore.kernel.org/r/20210112095437.6488-2-mailhol.vincent@wanadoo.fr
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2021-01-14 08:43:44 +01:00
Marc Kleine-Budde 99842c9685 can: dev: can_rx_offload_get_echo_skb(): extend to return can frame length
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 <mailhol.vincent@wanadoo.fr>
Link: https://lore.kernel.org/r/20210111141930.693847-15-mkl@pengutronix.de
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2021-01-14 08:43:43 +01:00
Marc Kleine-Budde 9420e1d495 can: dev: can_get_echo_skb(): extend to return can frame length
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 <mailhol.vincent@wanadoo.fr>
Link: https://lore.kernel.org/r/20210111141930.693847-14-mkl@pengutronix.de
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2021-01-14 08:43:43 +01:00
Vincent Mailhol 1dcb6e57db can: dev: can_put_echo_skb(): extend to handle frame_len
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 <mkl@pengutronix.de>
Reviewed-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Link: https://lore.kernel.org/r/20210111141930.693847-13-mkl@pengutronix.de
Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
2021-01-14 08:43:43 +01:00
Marc Kleine-Budde f0ef72febc can: dev: extend struct can_skb_priv to hold CAN frame length
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 the struct can_skb_priv to hold
the length of the CAN frame and extend __can_get_echo_skb() to return that
value.

Reviewed-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Link: https://lore.kernel.org/r/20210111141930.693847-12-mkl@pengutronix.de
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2021-01-14 08:43:42 +01:00
Vincent Mailhol 85d99c3e2a can: length: can_skb_get_frame_len(): introduce function to get data length of frame in data link layer
This patch adds the function can_skb_get_frame_len() which returns the length
of a CAN frame on the data link layer, including Start-of-frame, Identifier,
various other bits, the actual data, the CRC, the End-of-frame, the Inter frame
spacing.

Co-developed-by: Arunachalam Santhanam <arunachalam.santhanam@in.bosch.com>
Signed-off-by: Arunachalam Santhanam <arunachalam.santhanam@in.bosch.com>
Co-developed-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Acked-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Reviewed-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Co-developed-by: Marc Kleine-Budde <mkl@pengutronix.de>
Link: https://lore.kernel.org/r/20210111141930.693847-11-mkl@pengutronix.de
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2021-01-14 08:43:42 +01:00
Marc Kleine-Budde 652562e5ff can: length: can_fd_len2dlc(): simplify length calculcation
If the length paramter in len2dlc() exceeds the size of the len2dlc array, we
return 0xF. This is equal to the last 16 members of the array.

This patch removes these members from the array, uses ARRAY_SIZE() for the
length check, and returns CANFD_MAX_DLC (which is 0xf).

Reviewed-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Link: https://lore.kernel.org/r/20210111141930.693847-9-mkl@pengutronix.de
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2021-01-14 08:43:41 +01:00
Marc Kleine-Budde 1ea0a52289 can: length: convert to kernel coding style
This patch converts the file into the kernel coding style.

Reviewed-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Link: https://lore.kernel.org/r/20210111141930.693847-8-mkl@pengutronix.de
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2021-01-13 09:42:59 +01:00
Marc Kleine-Budde 0a042c6ec9 can: dev: move netlink related code into seperate file
This patch moves the netlink related code of the CAN device infrastructure into
a separate file.

Reviewed-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Link: https://lore.kernel.org/r/20210111141930.693847-7-mkl@pengutronix.de
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2021-01-13 09:42:59 +01:00
Marc Kleine-Budde 18f2dbfd22 can: dev: move skb related into seperate file
This patch moves the skb related code of the CAN device infrastructure into a
separate file.

Reviewed-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Link: https://lore.kernel.org/r/20210111141930.693847-6-mkl@pengutronix.de
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2021-01-13 09:42:59 +01:00
Marc Kleine-Budde bdd2e41319 can: dev: move length related code into seperate file
This patch moves all CAN frame length related code of the CAN device
infrastructure into a separate file.

Reviewed-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Link: https://lore.kernel.org/r/20210111141930.693847-5-mkl@pengutronix.de
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2021-01-13 09:42:59 +01:00
Marc Kleine-Budde 5a9d5ecd69 can: dev: move bittiming related code into seperate file
This patch moves the bittiming related code of the CAN device infrastructure
into a separate file.

Reviewed-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Link: https://lore.kernel.org/r/20210111141930.693847-4-mkl@pengutronix.de
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2021-01-13 09:42:58 +01:00
Marc Kleine-Budde 3e77f70e73 can: dev: move driver related infrastructure into separate subdir
This patch moves the CAN driver related infrastructure into a separate subdir.
It will be split into more files in the coming patches.

Reviewed-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Link: https://lore.kernel.org/r/20210111141930.693847-3-mkl@pengutronix.de
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2021-01-13 09:42:58 +01:00