4.9-stable patches

added patches:
	can-dev-move-device-back-to-init-netns-on-owning-netns-delete.patch

diff --git a/queue-4.9/can-dev-move-device-back-to-init-netns-on-owning-netns-delete.patch b/queue-4.9/can-dev-move-device-back-to-init-netns-on-owning-netns-delete.patch
new file mode 100644 (file)
index 0000000..a21d829
--- /dev/null
+++ b/queue-4.9/can-dev-move-device-back-to-init-netns-on-owning-netns-delete.patch
@@ -0,0 +1,96 @@
+From 3a5ca857079ea022e0b1b17fc154f7ad7dbc150f Mon Sep 17 00:00:00 2001
+From: Martin Willi <martin@strongswan.org>
+Date: Tue, 2 Mar 2021 13:24:23 +0100
+Subject: can: dev: Move device back to init netns on owning netns delete
+
+From: Martin Willi <martin@strongswan.org>
+
+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: 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 <martin@strongswan.org>
+Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ drivers/net/can/dev.c   |    1 +
+ include/net/rtnetlink.h |    2 ++
+ net/core/dev.c          |    2 +-
+ 3 files changed, 4 insertions(+), 1 deletion(-)
+
+--- a/drivers/net/can/dev.c
++++ b/drivers/net/can/dev.c
+@@ -1084,6 +1084,7 @@ static void can_dellink(struct net_devic
+ 
+ static struct rtnl_link_ops can_link_ops __read_mostly = {
+       .kind           = "can",
++      .netns_refund   = true,
+       .maxtype        = IFLA_CAN_MAX,
+       .policy         = can_policy,
+       .setup          = can_setup,
+--- a/include/net/rtnetlink.h
++++ b/include/net/rtnetlink.h
+@@ -28,6 +28,7 @@ static inline int rtnl_msg_family(const
+  *
+  *    @list: Used internally
+  *    @kind: Identifier
++ *    @netns_refund: Physical device, move to init_net on netns exit
+  *    @maxtype: Highest device specific netlink attribute number
+  *    @policy: Netlink policy for device specific attribute validation
+  *    @validate: Optional validation function for netlink/changelink parameters
+@@ -84,6 +85,7 @@ struct rtnl_link_ops {
+       unsigned int            (*get_num_tx_queues)(void);
+       unsigned int            (*get_num_rx_queues)(void);
+ 
++      bool                    netns_refund;
+       int                     slave_maxtype;
+       const struct nla_policy *slave_policy;
+       int                     (*slave_validate)(struct nlattr *tb[],
+--- a/net/core/dev.c
++++ b/net/core/dev.c
+@@ -8300,7 +8300,7 @@ static void __net_exit default_device_ex
+                       continue;
+ 
+               /* Leave virtual devices for the generic cleanup */
+-              if (dev->rtnl_link_ops)
++              if (dev->rtnl_link_ops && !dev->rtnl_link_ops->netns_refund)
+                       continue;
+ 
+               /* Push remaining network devices to init_net */

diff --git a/queue-4.9/series b/queue-4.9/series
index 240edd61d6e8f3f7a9802384abeb63a7b6ebb6bb..0101b9bedf04317b18ddb229aa7ae89b6acf26e4 100644 (file)
--- a/queue-4.9/series
+++ b/queue-4.9/series
@@ -47,3 +47,4 @@ arm64-futex-bound-number-of-ldxr-stxr-loops-in-futex_wake_op.patch
 futex-prevent-robust-futex-exit-race.patch
 futex-fix-incorrect-should_fail_futex-handling.patch
 futex-handle-transient-ownerless-rtmutex-state-correctly.patch
+can-dev-move-device-back-to-init-netns-on-owning-netns-delete.patch