diff options
| author | Linus Lüssing <linus.luessing@c0d3.blue> | 2015-06-16 17:10:22 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2015-10-22 14:43:21 -0700 |
| commit | 7abb2eeda8ce0ad0516d638e7bbeaacf745d4d75 (patch) | |
| tree | c764415bfb425f86d990813dfd7538d954e36506 | |
| parent | 103c584bcde170c3035041d85e79a90eae177eaf (diff) | |
batman-adv: Make DAT capability changes atomic
commit 65d7d46050704bcdb8121ddbf4110bfbf2b38baa 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: 17cf0ea455f1 ("batman-adv: tvlv - add distributed arp table 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>
| -rw-r--r-- | net/batman-adv/distributed-arp-table.c | 7 | ||||
| -rw-r--r-- | net/batman-adv/types.h | 4 |
2 files changed, 6 insertions, 5 deletions
diff --git a/net/batman-adv/distributed-arp-table.c b/net/batman-adv/distributed-arp-table.c index aad022dd15df..95b3167cf036 100644 --- a/net/batman-adv/distributed-arp-table.c +++ b/net/batman-adv/distributed-arp-table.c @@ -15,6 +15,7 @@ * along with this program; if not, see <http://www.gnu.org/licenses/>. */ +#include <linux/bitops.h> #include <linux/if_ether.h> #include <linux/if_arp.h> #include <linux/if_vlan.h> @@ -422,7 +423,7 @@ static bool batadv_is_orig_node_eligible(struct batadv_dat_candidate *res, int j; /* check if orig node candidate is running DAT */ - if (!(candidate->capabilities & BATADV_ORIG_CAPA_HAS_DAT)) + if (!test_bit(BATADV_ORIG_CAPA_HAS_DAT, &candidate->capabilities)) goto out; /* Check if this node has already been selected... */ @@ -682,9 +683,9 @@ static void batadv_dat_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_DAT; + clear_bit(BATADV_ORIG_CAPA_HAS_DAT, &orig->capabilities); else - orig->capabilities |= BATADV_ORIG_CAPA_HAS_DAT; + set_bit(BATADV_ORIG_CAPA_HAS_DAT, &orig->capabilities); } /** diff --git a/net/batman-adv/types.h b/net/batman-adv/types.h index 9398c3fb4174..4fff13cc66b4 100644 --- a/net/batman-adv/types.h +++ b/net/batman-adv/types.h @@ -256,7 +256,7 @@ struct batadv_orig_node { struct hlist_node mcast_want_all_ipv4_node; struct hlist_node mcast_want_all_ipv6_node; #endif - uint8_t capabilities; + unsigned long capabilities; uint8_t capa_initialized; atomic_t last_ttvn; unsigned char *tt_buff; @@ -296,7 +296,7 @@ struct batadv_orig_node { * (= orig node announces a tvlv of type BATADV_TVLV_MCAST) */ enum batadv_orig_capabilities { - BATADV_ORIG_CAPA_HAS_DAT = BIT(0), + BATADV_ORIG_CAPA_HAS_DAT, BATADV_ORIG_CAPA_HAS_NC = BIT(1), BATADV_ORIG_CAPA_HAS_TT = BIT(2), BATADV_ORIG_CAPA_HAS_MCAST = BIT(3), |