[PATCH 06/14] batman-adv: Make TT capability changes atomic
From: Antonio Quartulli <hidden>
Date: 2015-08-04 16:53:56
Subsystem:
batman advanced, the rest · Maintainers:
Marek Lindner, Simon Wunderlich, Antonio Quartulli, Sven Eckelmann, Linus Torvalds
From: Linus Lüssing <redacted>
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 <redacted>
Signed-off-by: Marek Lindner <redacted>
Signed-off-by: Antonio Quartulli <redacted>
---
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 b482495..1573489 100644
--- a/net/batman-adv/translation-table.c
+++ b/net/batman-adv/translation-table.c@@ -19,6 +19,7 @@ #include "main.h" #include <linux/atomic.h> +#include <linux/bitops.h> #include <linux/bug.h> #include <linux/byteorder/generic.h> #include <linux/compiler.h>
@@ -1862,7 +1863,7 @@ 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,
@@ -2821,7 +2822,7 @@ 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,
@@ -3321,7 +3322,8 @@ 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 ed4aec5..6f801ef 100644
--- a/net/batman-adv/types.h
+++ b/net/batman-adv/types.h@@ -274,7 +274,7 @@ 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;
@@ -315,7 +315,7 @@ 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), };
--
2.5.0