releases/5.0.1/team-free-bpf-filter-when-unregistering-netdev.patch

   1 From foo@baz Fri Mar  8 07:37:28 CET 2019
   2 From: Ido Schimmel <idosch@mellanox.com>
   3 Date: Sun, 3 Mar 2019 07:35:51 +0000
   4 Subject: team: Free BPF filter when unregistering netdev
   5
   6 From: Ido Schimmel <idosch@mellanox.com>
   7
   8 [ Upstream commit 692c31bd4054212312396b1d303bffab2c5b93a7 ]
   9
  10 When team is used in loadbalance mode a BPF filter can be used to
  11 provide a hash which will determine the Tx port.
  12
  13 When the netdev is later unregistered the filter is not freed which
  14 results in memory leaks [1].
  15
  16 Fix by freeing the program and the corresponding filter when
  17 unregistering the netdev.
  18
  19 [1]
  20 unreferenced object 0xffff8881dbc47cc8 (size 16):
  21   comm "teamd", pid 3068, jiffies 4294997779 (age 438.247s)
  22   hex dump (first 16 bytes):
  23     a3 00 6b 6b 6b 6b 6b 6b 88 a5 82 e1 81 88 ff ff  ..kkkkkk........
  24   backtrace:
  25     [<000000008a3b47e3>] team_nl_cmd_options_set+0x88f/0x11b0
  26     [<00000000c4f4f27e>] genl_family_rcv_msg+0x78f/0x1080
  27     [<00000000610ef838>] genl_rcv_msg+0xca/0x170
  28     [<00000000a281df93>] netlink_rcv_skb+0x132/0x380
  29     [<000000004d9448a2>] genl_rcv+0x29/0x40
  30     [<000000000321b2f4>] netlink_unicast+0x4c0/0x690
  31     [<000000008c25dffb>] netlink_sendmsg+0x929/0xe10
  32     [<00000000068298c5>] sock_sendmsg+0xc8/0x110
  33     [<0000000082a61ff0>] ___sys_sendmsg+0x77a/0x8f0
  34     [<00000000663ae29d>] __sys_sendmsg+0xf7/0x250
  35     [<0000000027c5f11a>] do_syscall_64+0x14d/0x610
  36     [<000000006cfbc8d3>] entry_SYSCALL_64_after_hwframe+0x49/0xbe
  37     [<00000000e23197e2>] 0xffffffffffffffff
  38 unreferenced object 0xffff8881e182a588 (size 2048):
  39   comm "teamd", pid 3068, jiffies 4294997780 (age 438.247s)
  40   hex dump (first 32 bytes):
  41     20 00 00 00 02 00 00 00 30 00 00 00 28 f0 ff ff   .......0...(...
  42     07 00 00 00 00 00 00 00 28 00 00 00 00 00 00 00  ........(.......
  43   backtrace:
  44     [<000000002daf01fb>] lb_bpf_func_set+0x45c/0x6d0
  45     [<000000008a3b47e3>] team_nl_cmd_options_set+0x88f/0x11b0
  46     [<00000000c4f4f27e>] genl_family_rcv_msg+0x78f/0x1080
  47     [<00000000610ef838>] genl_rcv_msg+0xca/0x170
  48     [<00000000a281df93>] netlink_rcv_skb+0x132/0x380
  49     [<000000004d9448a2>] genl_rcv+0x29/0x40
  50     [<000000000321b2f4>] netlink_unicast+0x4c0/0x690
  51     [<000000008c25dffb>] netlink_sendmsg+0x929/0xe10
  52     [<00000000068298c5>] sock_sendmsg+0xc8/0x110
  53     [<0000000082a61ff0>] ___sys_sendmsg+0x77a/0x8f0
  54     [<00000000663ae29d>] __sys_sendmsg+0xf7/0x250
  55     [<0000000027c5f11a>] do_syscall_64+0x14d/0x610
  56     [<000000006cfbc8d3>] entry_SYSCALL_64_after_hwframe+0x49/0xbe
  57     [<00000000e23197e2>] 0xffffffffffffffff
  58
  59 Fixes: 01d7f30a9f96 ("team: add loadbalance mode")
  60 Signed-off-by: Ido Schimmel <idosch@mellanox.com>
  61 Reported-by: Amit Cohen <amitc@mellanox.com>
  62 Acked-by: Jiri Pirko <jiri@mellanox.com>
  63 Signed-off-by: David S. Miller <davem@davemloft.net>
  64 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
  65 ---
  66  drivers/net/team/team_mode_loadbalance.c |   15 +++++++++++++++
  67  1 file changed, 15 insertions(+)
  68
  69 --- a/drivers/net/team/team_mode_loadbalance.c
  70 +++ b/drivers/net/team/team_mode_loadbalance.c
  71 @@ -325,6 +325,20 @@ static int lb_bpf_func_set(struct team *
  72         return 0;
  73  }
  74
  75 +static void lb_bpf_func_free(struct team *team)
  76 +{
  77 +       struct lb_priv *lb_priv = get_lb_priv(team);
  78 +       struct bpf_prog *fp;
  79 +
  80 +       if (!lb_priv->ex->orig_fprog)
  81 +               return;
  82 +
  83 +       __fprog_destroy(lb_priv->ex->orig_fprog);
  84 +       fp = rcu_dereference_protected(lb_priv->fp,
  85 +                                      lockdep_is_held(&team->lock));
  86 +       bpf_prog_destroy(fp);
  87 +}
  88 +
  89  static int lb_tx_method_get(struct team *team, struct team_gsetter_ctx *ctx)
  90  {
  91         struct lb_priv *lb_priv = get_lb_priv(team);
  92 @@ -639,6 +653,7 @@ static void lb_exit(struct team *team)
  93
  94         team_options_unregister(team, lb_options,
  95                                 ARRAY_SIZE(lb_options));
  96 +       lb_bpf_func_free(team);
  97         cancel_delayed_work_sync(&lb_priv->ex->stats.refresh_dw);
  98         free_percpu(lb_priv->pcpu_stats);
  99         kfree(lb_priv->ex);