From 722ccda13bc2ccfe3ca9331ae24d898c99b87432 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Linus=20L=C3=BCssing?= Date: Tue, 16 Jun 2015 17:10:24 +0200 Subject: [PATCH] batman-adv: Make TT capability changes atomic MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit [ Upstream commit ac4eebd48461ec993e7cb614d5afe7df8c72e6b7 ] Bitwise OR/AND assignments in C aren't guaranteed to be atomic. One OGM handler might undo the set/clear of a specific bit from another handler run in between. Fix this by using the atomic set_bit()/clear_bit()/test_bit() functions. Fixes: e17931d1a61d ("batman-adv: introduce capability initialization bitfield") Signed-off-by: Linus Lüssing Signed-off-by: Marek Lindner Signed-off-by: Antonio Quartulli Signed-off-by: Sasha Levin --- net/batman-adv/translation-table.c | 8 +++++--- net/batman-adv/types.h | 4 ++-- 2 files changed, 7 insertions(+), 5 deletions(-) diff --git a/net/batman-adv/translation-table.c b/net/batman-adv/translation-table.c index c8c5184a92bb..58ad6ba429b3 100644 --- a/net/batman-adv/translation-table.c +++ b/net/batman-adv/translation-table.c @@ -15,6 +15,7 @@ * along with this program; if not, see . */ +#include #include "main.h" #include "translation-table.h" #include "soft-interface.h" @@ -1853,7 +1854,7 @@ void batadv_tt_global_del_orig(struct batadv_priv *bat_priv, } spin_unlock_bh(list_lock); } - orig_node->capa_initialized &= ~BATADV_ORIG_CAPA_HAS_TT; + clear_bit(BATADV_ORIG_CAPA_HAS_TT, &orig_node->capa_initialized); } static bool batadv_tt_global_to_purge(struct batadv_tt_global_entry *tt_global, @@ -2813,7 +2814,7 @@ static void _batadv_tt_update_changes(struct batadv_priv *bat_priv, return; } } - orig_node->capa_initialized |= BATADV_ORIG_CAPA_HAS_TT; + set_bit(BATADV_ORIG_CAPA_HAS_TT, &orig_node->capa_initialized); } static void batadv_tt_fill_gtable(struct batadv_priv *bat_priv, @@ -3313,7 +3314,8 @@ static void batadv_tt_update_orig(struct batadv_priv *bat_priv, bool has_tt_init; tt_vlan = (struct batadv_tvlv_tt_vlan_data *)tt_buff; - has_tt_init = orig_node->capa_initialized & BATADV_ORIG_CAPA_HAS_TT; + has_tt_init = test_bit(BATADV_ORIG_CAPA_HAS_TT, + &orig_node->capa_initialized); /* orig table not initialised AND first diff is in the OGM OR the ttvn * increased by one -> we can apply the attached changes diff --git a/net/batman-adv/types.h b/net/batman-adv/types.h index 1b0b053ae729..fdf65b50e3ec 100644 --- a/net/batman-adv/types.h +++ b/net/batman-adv/types.h @@ -259,7 +259,7 @@ struct batadv_orig_node { struct hlist_node mcast_want_all_ipv6_node; #endif unsigned long capabilities; - uint8_t capa_initialized; + unsigned long capa_initialized; atomic_t last_ttvn; unsigned char *tt_buff; int16_t tt_buff_len; @@ -300,7 +300,7 @@ struct batadv_orig_node { enum batadv_orig_capabilities { BATADV_ORIG_CAPA_HAS_DAT, BATADV_ORIG_CAPA_HAS_NC, - BATADV_ORIG_CAPA_HAS_TT = BIT(2), + BATADV_ORIG_CAPA_HAS_TT, BATADV_ORIG_CAPA_HAS_MCAST = BIT(3), };