diff options
| author | Linus Lüssing <linus.luessing@c0d3.blue> | 2015-06-16 17:10:23 +0200 |
|---|---|---|
| committer | Antonio Quartulli <antonio@meshcoding.com> | 2015-08-14 22:50:43 +0200 |
| commit | 4635469f5c617282f18c69643af36cd8c0acf707 (patch) | |
| tree | 2604ea78d94aaa647869619d1447b1cb77b0e600 /net/batman-adv | |
| parent | 65d7d46050704bcdb8121ddbf4110bfbf2b38baa (diff) | |
| download | lwn-4635469f5c617282f18c69643af36cd8c0acf707.tar.gz lwn-4635469f5c617282f18c69643af36cd8c0acf707.zip | |
batman-adv: Make NC capability changes atomic
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: 3f4841ffb336 ("batman-adv: tvlv - add network coding container")
Signed-off-by: Linus Lüssing <linus.luessing@c0d3.blue>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Antonio Quartulli <antonio@meshcoding.com>
Diffstat (limited to 'net/batman-adv')
| -rw-r--r-- | net/batman-adv/network-coding.c | 7 | ||||
| -rw-r--r-- | net/batman-adv/types.h | 2 |
2 files changed, 5 insertions, 4 deletions
diff --git a/net/batman-adv/network-coding.c b/net/batman-adv/network-coding.c index f0a50f31d822..46604010dcd4 100644 --- a/net/batman-adv/network-coding.c +++ b/net/batman-adv/network-coding.c @@ -19,6 +19,7 @@ #include "main.h" #include <linux/atomic.h> +#include <linux/bitops.h> #include <linux/byteorder/generic.h> #include <linux/compiler.h> #include <linux/debugfs.h> @@ -134,9 +135,9 @@ static void batadv_nc_tvlv_ogm_handler_v1(struct batadv_priv *bat_priv, uint16_t tvlv_value_len) { if (flags & BATADV_TVLV_HANDLER_OGM_CIFNOTFND) - orig->capabilities &= ~BATADV_ORIG_CAPA_HAS_NC; + clear_bit(BATADV_ORIG_CAPA_HAS_NC, &orig->capabilities); else - orig->capabilities |= BATADV_ORIG_CAPA_HAS_NC; + set_bit(BATADV_ORIG_CAPA_HAS_NC, &orig->capabilities); } /** @@ -894,7 +895,7 @@ void batadv_nc_update_nc_node(struct batadv_priv *bat_priv, goto out; /* check if orig node is network coding enabled */ - if (!(orig_node->capabilities & BATADV_ORIG_CAPA_HAS_NC)) + if (!test_bit(BATADV_ORIG_CAPA_HAS_NC, &orig_node->capabilities)) goto out; /* accept ogms from 'good' neighbors and single hop neighbors */ diff --git a/net/batman-adv/types.h b/net/batman-adv/types.h index 29fd62562546..ed4aec5cb8cc 100644 --- a/net/batman-adv/types.h +++ b/net/batman-adv/types.h @@ -314,7 +314,7 @@ struct batadv_orig_node { */ enum batadv_orig_capabilities { BATADV_ORIG_CAPA_HAS_DAT, - BATADV_ORIG_CAPA_HAS_NC = BIT(1), + BATADV_ORIG_CAPA_HAS_NC, BATADV_ORIG_CAPA_HAS_TT = BIT(2), BATADV_ORIG_CAPA_HAS_MCAST = BIT(3), }; |