mac80211: sparse RCU annotations
This adds sparse RCU annotations to most of
mac80211, only the mesh code remains to be
done.
Due the the previous patches, the annotations
are pretty simple. The only thing that this
actually changes is removing the RCU usage of
key->sta in debugfs since this pointer isn't
actually an RCU-managed pointer (it only has
a single assignment done before the key even
goes live). As that is otherwise harmless, I
decided to make it part of this patch.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/net/mac80211/mesh_hwmp.c b/net/mac80211/mesh_hwmp.c
index 2aec7c4..2b18053 100644
--- a/net/mac80211/mesh_hwmp.c
+++ b/net/mac80211/mesh_hwmp.c
@@ -560,6 +560,14 @@
}
+static inline struct sta_info *
+next_hop_deref_protected(struct mesh_path *mpath)
+{
+ return rcu_dereference_protected(mpath->next_hop,
+ lockdep_is_held(&mpath->state_lock));
+}
+
+
static void hwmp_prep_frame_process(struct ieee80211_sub_if_data *sdata,
struct ieee80211_mgmt *mgmt,
u8 *prep_elem, u32 metric)
@@ -599,7 +607,7 @@
spin_unlock_bh(&mpath->state_lock);
goto fail;
}
- memcpy(next_hop, mpath->next_hop->sta.addr, ETH_ALEN);
+ memcpy(next_hop, next_hop_deref_protected(mpath)->sta.addr, ETH_ALEN);
spin_unlock_bh(&mpath->state_lock);
--ttl;
flags = PREP_IE_FLAGS(prep_elem);
@@ -651,7 +659,8 @@
if (mpath) {
spin_lock_bh(&mpath->state_lock);
if (mpath->flags & MESH_PATH_ACTIVE &&
- memcmp(ta, mpath->next_hop->sta.addr, ETH_ALEN) == 0 &&
+ memcmp(ta, next_hop_deref_protected(mpath)->sta.addr,
+ ETH_ALEN) == 0 &&
(!(mpath->flags & MESH_PATH_SN_VALID) ||
SN_GT(target_sn, mpath->sn))) {
mpath->flags &= ~MESH_PATH_ACTIVE;
@@ -913,6 +922,7 @@
{
struct sk_buff *skb_to_free = NULL;
struct mesh_path *mpath;
+ struct sta_info *next_hop;
struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
u8 *target_addr = hdr->addr3;
int err = 0;
@@ -940,7 +950,11 @@
mesh_queue_preq(mpath,
PREQ_Q_F_START | PREQ_Q_F_REFRESH);
}
- memcpy(hdr->addr1, mpath->next_hop->sta.addr, ETH_ALEN);
+ next_hop = rcu_dereference(mpath->next_hop);
+ if (next_hop)
+ memcpy(hdr->addr1, next_hop->sta.addr, ETH_ALEN);
+ else
+ err = -ENOENT;
} else {
struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
if (!(mpath->flags & MESH_PATH_RESOLVING)) {