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() functions.
Fixes: 2b1c07b918d2 ("batman-adv: tvlv - add distributed arp table container") Signed-off-by: Linus Lüssing linus.luessing@c0d3.blue --- distributed-arp-table.c | 4 ++-- types.h | 2 +- 2 files changed, 3 insertions(+), 3 deletions(-)
diff --git a/distributed-arp-table.c b/distributed-arp-table.c index 0d791dc..b2cc19b 100644 --- a/distributed-arp-table.c +++ b/distributed-arp-table.c @@ -682,9 +682,9 @@ 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/types.h b/types.h index 28f2461..e33b5aa 100644 --- a/types.h +++ b/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;