Martin Willi 8dc08a2962 can: dev: Move device back to init netns on owning netns delete ... commit 3a5ca857079ea022e0b1b17fc154f7ad7dbc150f upstream. 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> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>		2021-03-30 14:32:08 +02:00
..
acpi	ACPI: scan: Use unique number for instance_no	2021-03-30 14:32:06 +02:00
asm-generic	static_call: Allow module use without exposing static_call_key	2021-03-30 14:31:53 +02:00
clocksource
crypto
drm
dt-bindings
keys
kunit
kvm
linux	fs/cachefiles: Remove wait_bit_key layout dependency	2021-03-30 14:32:07 +02:00
math-emu
media	media: rc: compile rc-cec.c into rc-core	2021-03-17 17:06:20 +01:00
memory
misc
net	can: dev: Move device back to init netns on owning netns delete	2021-03-30 14:32:08 +02:00
pcmcia
ras
rdma
scsi	scsi: libsas: Introduce a _gfp() variant of event notifiers	2021-03-25 09:04:11 +01:00
soc
sound
target	scsi: target: core: Add cmd length set before cmd complete	2021-03-17 17:06:25 +01:00
trace
uapi	psample: Fix user API breakage	2021-03-30 14:31:53 +02:00
vdso
video
xen