diff options
author | Linus Lüssing <linus.luessing@c0d3.blue> | 2015-06-16 17:10:23 +0200 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2015-10-22 14:43:23 -0700 |
commit | 505f068df9dd37bfa86114f746bacedc2b32437a (patch) | |
tree | 2e52b01d8f9da770b30fa68c89d1e6d296210359 /net/batman-adv/network-coding.c | |
parent | 88108b384f4817c9f935ad0932e2fce80d790a2e (diff) |
batman-adv: Make NC capability changes atomic
commit 4635469f5c617282f18c69643af36cd8c0acf707 upstream.
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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'net/batman-adv/network-coding.c')
-rw-r--r-- | net/batman-adv/network-coding.c | 7 |
1 files changed, 4 insertions, 3 deletions
diff --git a/net/batman-adv/network-coding.c b/net/batman-adv/network-coding.c index 127cc4d7380a..a449195c5b2b 100644 --- a/net/batman-adv/network-coding.c +++ b/net/batman-adv/network-coding.c @@ -15,6 +15,7 @@ * along with this program; if not, see <http://www.gnu.org/licenses/>. */ +#include <linux/bitops.h> #include <linux/debugfs.h> #include "main.h" @@ -105,9 +106,9 @@ 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); } /** @@ -871,7 +872,7 @@ 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 */ |