linux/net/bridge
Ido Schimmel 9d45921ee4 bridge: switchdev: Fix memory leaks when changing VLAN protocol
The bridge driver can offload VLANs to the underlying hardware either
via switchdev or the 8021q driver. When the former is used, the VLAN is
marked in the bridge driver with the 'BR_VLFLAG_ADDED_BY_SWITCHDEV'
private flag.

To avoid the memory leaks mentioned in the cited commit, the bridge
driver will try to delete a VLAN via the 8021q driver if the VLAN is not
marked with the previously mentioned flag.

When the VLAN protocol of the bridge changes, switchdev drivers are
notified via the 'SWITCHDEV_ATTR_ID_BRIDGE_VLAN_PROTOCOL' attribute, but
the 8021q driver is also called to add the existing VLANs with the new
protocol and delete them with the old protocol.

In case the VLANs were offloaded via switchdev, the above behavior is
both redundant and buggy. Redundant because the VLANs are already
programmed in hardware and drivers that support VLAN protocol change
(currently only mlx5) change the protocol upon the switchdev attribute
notification. Buggy because the 8021q driver is called despite these
VLANs being marked with 'BR_VLFLAG_ADDED_BY_SWITCHDEV'. This leads to
memory leaks [1] when the VLANs are deleted.

Fix by not calling the 8021q driver for VLANs that were already
programmed via switchdev.

[1]
unreferenced object 0xffff8881f6771200 (size 256):
  comm "ip", pid 446855, jiffies 4298238841 (age 55.240s)
  hex dump (first 32 bytes):
    00 00 7f 0e 83 88 ff ff 00 00 00 00 00 00 00 00  ................
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
  backtrace:
    [<00000000012819ac>] vlan_vid_add+0x437/0x750
    [<00000000f2281fad>] __br_vlan_set_proto+0x289/0x920
    [<000000000632b56f>] br_changelink+0x3d6/0x13f0
    [<0000000089d25f04>] __rtnl_newlink+0x8ae/0x14c0
    [<00000000f6276baf>] rtnl_newlink+0x5f/0x90
    [<00000000746dc902>] rtnetlink_rcv_msg+0x336/0xa00
    [<000000001c2241c0>] netlink_rcv_skb+0x11d/0x340
    [<0000000010588814>] netlink_unicast+0x438/0x710
    [<00000000e1a4cd5c>] netlink_sendmsg+0x788/0xc40
    [<00000000e8992d4e>] sock_sendmsg+0xb0/0xe0
    [<00000000621b8f91>] ____sys_sendmsg+0x4ff/0x6d0
    [<000000000ea26996>] ___sys_sendmsg+0x12e/0x1b0
    [<00000000684f7e25>] __sys_sendmsg+0xab/0x130
    [<000000004538b104>] do_syscall_64+0x3d/0x90
    [<0000000091ed9678>] entry_SYSCALL_64_after_hwframe+0x46/0xb0

Fixes: 279737939a ("net: bridge: Fix VLANs memory leak")
Reported-by: Vlad Buslov <vladbu@nvidia.com>
Tested-by: Vlad Buslov <vladbu@nvidia.com>
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Link: https://lore.kernel.org/r/20221114084509.860831-1-idosch@nvidia.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2022-11-15 13:38:11 +01:00
..
netfilter Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2022-09-22 13:02:10 -07:00
br_arp_nd_proxy.c net: bridge: Use netif_rx(). 2022-03-04 12:02:19 +00:00
br_cfm_netlink.c
br_cfm.c bridge: cfm: remove redundant return 2021-06-22 10:35:15 -07:00
br_device.c bridge: move from strlcpy with unused retval to strscpy 2022-08-22 17:57:30 -07:00
br_fdb.c rtnetlink: add extack support in fdb del handlers 2022-05-09 11:58:20 +01:00
br_forward.c net: Add skb_clear_tstamp() to keep the mono delivery_time 2022-03-03 14:38:48 +00:00
br_if.c net: bridge: assign path_cost for 2.5G and 5G link speed 2022-09-30 12:35:29 +01:00
br_input.c net: bridge: Clear offload_fwd_mark when passing frame up bridge interface. 2022-05-19 09:20:44 +02:00
br_ioctl.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next 2021-12-31 14:35:40 +00:00
br_mdb.c net: bridge: allow add/remove permanent mdb entries on disabled ports 2022-06-15 09:35:21 +01:00
br_mrp_netlink.c
br_mrp_switchdev.c bridge: mrp: Extend br_mrp_switchdev to detect better the errors 2021-02-16 14:47:46 -08:00
br_mrp.c net: bridge: mrp: Update the Test frames for MRA 2021-06-28 15:46:10 -07:00
br_mst.c net: bridge: mst: Add helper to query a port's MST state 2022-03-17 16:49:58 -07:00
br_multicast_eht.c net: bridge: multicast: use multicast contexts instead of bridge or port 2021-07-20 05:41:19 -07:00
br_multicast.c net: bridge: multicast: notify switchdev driver whenever MC processing gets disabled 2022-02-16 20:35:00 -08:00
br_netfilter_hooks.c netfilter: br_netfilter: Drop dst references before setting. 2022-08-31 12:12:32 +02:00
br_netfilter_ipv6.c netfilter: br_netfilter: Drop dst references before setting. 2022-08-31 12:12:32 +02:00
br_netlink_tunnel.c
br_netlink.c bridge: Fix flushing of dynamic FDB entries 2022-11-02 20:47:09 -07:00
br_nf_core.c
br_private_cfm.h
br_private_mcast_eht.h net: bridge: multicast: use multicast contexts instead of bridge or port 2021-07-20 05:41:19 -07:00
br_private_mrp.h net: bridge: mrp: Update the Test frames for MRA 2021-06-28 15:46:10 -07:00
br_private_stp.h
br_private_tunnel.h net: bridge: change return type of br_handle_ingress_vlan_tunnel 2021-08-24 16:51:09 -07:00
br_private.h rtnetlink: add extack support in fdb del handlers 2022-05-09 11:58:20 +01:00
br_stp_bpdu.c
br_stp_if.c net: use eth_hw_addr_set() 2021-10-02 14:18:25 +01:00
br_stp_timer.c
br_stp.c net: bridge: mst: Multiple Spanning Tree (MST) mode 2022-03-17 16:49:57 -07:00
br_switchdev.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2022-04-28 13:02:01 -07:00
br_sysfs_br.c bridge: Fix flushing of dynamic FDB entries 2022-11-02 20:47:09 -07:00
br_sysfs_if.c bridge: move from strlcpy with unused retval to strscpy 2022-08-22 17:57:30 -07:00
br_vlan_options.c net: bridge: mst: Allow changing a VLAN's MSTI 2022-03-17 16:49:57 -07:00
br_vlan_tunnel.c net: bridge: change return type of br_handle_ingress_vlan_tunnel 2021-08-24 16:51:09 -07:00
br_vlan.c bridge: switchdev: Fix memory leaks when changing VLAN protocol 2022-11-15 13:38:11 +01:00
br.c net: bridge: mst: Multiple Spanning Tree (MST) mode 2022-03-17 16:49:57 -07:00
Kconfig
Makefile net: bridge: mst: Multiple Spanning Tree (MST) mode 2022-03-17 16:49:57 -07:00