batman-adv/patches/0003-batman-adv-Make-DAT-capability-changes-atomic.patch

   1 From bfd0fbaef270ac4ed8e4457a38ef8d91190c0540 Mon Sep 17 00:00:00 2001
   2 From: =?UTF-8?q?Linus=20L=C3=BCssing?= <linus.luessing@c0d3.blue>
   3 Date: Tue, 16 Jun 2015 17:10:22 +0200
   4 Subject: [PATCH 03/17] batman-adv: Make DAT capability changes atomic
   5 MIME-Version: 1.0
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   8
   9 Bitwise OR/AND assignments in C aren't guaranteed to be atomic. One
  10 OGM handler might undo the set/clear of a specific bit from another
  11 handler run in between.
  12
  13 Fix this by using the atomic set_bit()/clear_bit() functions.
  14
  15 Fixes: 2b1c07b918d2 ("batman-adv: tvlv - add distributed arp table container")
  16 Signed-off-by: Linus Lüssing <linus.luessing@c0d3.blue>
  17 Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
  18 ---
  19  distributed-arp-table.c | 4 ++--
  20  types.h                 | 2 +-
  21  2 files changed, 3 insertions(+), 3 deletions(-)
  22
  23 diff --git a/distributed-arp-table.c b/distributed-arp-table.c
  24 index 0d791dc..b2cc19b 100644
  25 --- a/distributed-arp-table.c
  26 +++ b/distributed-arp-table.c
  27 @@ -682,9 +682,9 @@ static void batadv_dat_tvlv_ogm_handler_v1(struct batadv_priv *bat_priv,
  28                                            uint16_t tvlv_value_len)
  29  {
  30         if (flags & BATADV_TVLV_HANDLER_OGM_CIFNOTFND)
  31 -               orig->capabilities &= ~BATADV_ORIG_CAPA_HAS_DAT;
  32 +               clear_bit(BATADV_ORIG_CAPA_HAS_DAT, &orig->capabilities);
  33         else
  34 -               orig->capabilities |= BATADV_ORIG_CAPA_HAS_DAT;
  35 +               set_bit(BATADV_ORIG_CAPA_HAS_DAT, &orig->capabilities);
  36  }
  37
  38  /**
  39 diff --git a/types.h b/types.h
  40 index 28f2461..e33b5aa 100644
  41 --- a/types.h
  42 +++ b/types.h
  43 @@ -256,7 +256,7 @@ struct batadv_orig_node {
  44         struct hlist_node mcast_want_all_ipv4_node;
  45         struct hlist_node mcast_want_all_ipv6_node;
  46  #endif
  47 -       uint8_t capabilities;
  48 +       unsigned long capabilities;
  49         uint8_t capa_initialized;
  50         atomic_t last_ttvn;
  51         unsigned char *tt_buff;
  52 --
  53 2.1.4
  54