From: Ben Greear <greearb@candelatech.com> Date: Fri, 1 Apr 2016 14:12:09 -0700 Subject: [PATCH] ath10k: Ensure peer_map references are cleaned up. While debugging OS crashes due to firmware crashes, I enabled kasan, and it noticed that peer objects were being used-after-freed. Looks like there are two places we could be leaving stale references in the peer-map, so clean that up. Signed-off-by: Ben Greear <greearb@candelatech.com> --- --- a/drivers/net/wireless/ath/ath10k/mac.c +++ b/drivers/net/wireless/ath/ath10k/mac.c @@ -802,6 +802,7 @@ static void ath10k_peer_cleanup(struct a { struct ath10k_peer *peer, *tmp; int peer_id; + int i; lockdep_assert_held(&ar->conf_mutex); @@ -818,6 +819,17 @@ static void ath10k_peer_cleanup(struct a ar->peer_map[peer_id] = NULL; } + /* Double check that peer is properly un-referenced from + * the peer_map + */ + for (i = 0; i < ARRAY_SIZE(ar->peer_map); i++) { + if (ar->peer_map[i] == peer) { + ath10k_warn(ar, "removing stale peer_map entry for %pM (ptr %p idx %d)\n", + peer->addr, peer, i); + ar->peer_map[i] = NULL; + } + } + list_del(&peer->list); kfree(peer); ar->num_peers--; @@ -828,6 +840,7 @@ static void ath10k_peer_cleanup(struct a static void ath10k_peer_cleanup_all(struct ath10k *ar) { struct ath10k_peer *peer, *tmp; + int i; lockdep_assert_held(&ar->conf_mutex); @@ -836,6 +849,10 @@ static void ath10k_peer_cleanup_all(stru list_del(&peer->list); kfree(peer); } + + for (i = 0; i < ARRAY_SIZE(ar->peer_map); i++) + ar->peer_map[i] = NULL; + spin_unlock_bh(&ar->data_lock); ar->num_peers = 0;