net/mlx5e: Fix nullptr on deleting mirroring rule
authorDima Chumak <dchumak@nvidia.com>
Wed, 24 Nov 2021 07:37:26 +0000 (09:37 +0200)
committerSaeed Mahameed <saeedm@nvidia.com>
Fri, 7 Jan 2022 00:55:39 +0000 (16:55 -0800)
commitde31854ece175e12ff3c35d07f340988823aed34
treeae837f93d10616f345766c926b32e0ddeeaaddd6
parent0b7cfa4082fbf550595bc0e40f05614bd83bf0cd
net/mlx5e: Fix nullptr on deleting mirroring rule

Deleting a Tc rule with multiple outputs, one of which is internal port,
like this one:

  tc filter del dev enp8s0f0_0 ingress protocol ip pref 5 flower \
      dst_mac 0c:42:a1:d1:d0:88 \
      src_mac e4:ea:09:08:00:02 \
      action tunnel_key  set \
          src_ip 0.0.0.0 \
          dst_ip 7.7.7.8 \
          id 8 \
          dst_port 4789 \
      action mirred egress mirror dev vxlan_sys_4789 pipe \
      action mirred egress redirect dev enp8s0f0_1

Triggers a call trace:

  BUG: kernel NULL pointer dereference, address: 0000000000000230
  RIP: 0010:del_sw_hw_rule+0x2b/0x1f0 [mlx5_core]
  Call Trace:
   tree_remove_node+0x16/0x30 [mlx5_core]
   mlx5_del_flow_rules+0x51/0x160 [mlx5_core]
   __mlx5_eswitch_del_rule+0x4b/0x170 [mlx5_core]
   mlx5e_tc_del_fdb_flow+0x295/0x550 [mlx5_core]
   mlx5e_flow_put+0x1f/0x70 [mlx5_core]
   mlx5e_delete_flower+0x286/0x390 [mlx5_core]
   tc_setup_cb_destroy+0xac/0x170
   fl_hw_destroy_filter+0x94/0xc0 [cls_flower]
   __fl_delete+0x15e/0x170 [cls_flower]
   fl_delete+0x36/0x80 [cls_flower]
   tc_del_tfilter+0x3a6/0x6e0
   rtnetlink_rcv_msg+0xe5/0x360
   ? rtnl_calcit.isra.0+0x110/0x110
   netlink_rcv_skb+0x46/0x110
   netlink_unicast+0x16b/0x200
   netlink_sendmsg+0x202/0x3d0
   sock_sendmsg+0x33/0x40
   ____sys_sendmsg+0x1c3/0x200
   ? copy_msghdr_from_user+0xd6/0x150
   ___sys_sendmsg+0x88/0xd0
   ? ___sys_recvmsg+0x88/0xc0
   ? do_futex+0x10c/0x460
   __sys_sendmsg+0x59/0xa0
   do_syscall_64+0x48/0x140
   entry_SYSCALL_64_after_hwframe+0x44/0xa9

Fix by disabling offloading for flows matching
esw_is_chain_src_port_rewrite() which have more than one output.

Fixes: 10742efc20a4 ("net/mlx5e: VF tunnel TX traffic offloading")
Signed-off-by: Dima Chumak <dchumak@nvidia.com>
Reviewed-by: Roi Dayan <roid@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>
drivers/net/ethernet/mellanox/mlx5/core/eswitch_offloads.c