mac80211: use a counter for remain-on-channel cookie
Instead of using the pointer which can be re-used
fairly quickly due to allocator patterns and then
makes debugging difficult, maintain a counter and
use its value. Since it's a 64-bit value it can't
really wrap, but catch that case anyway since it
most likely points to a bug somewhere.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
diff --git a/net/mac80211/cfg.c b/net/mac80211/cfg.c
index 986e9a1..eebb70b 100644
--- a/net/mac80211/cfg.c
+++ b/net/mac80211/cfg.c
@@ -2382,13 +2382,22 @@
list_add_tail(&roc->list, &local->roc_list);
/*
- * cookie is either the roc (for normal roc)
+ * cookie is either the roc cookie (for normal roc)
* or the SKB (for mgmt TX)
*/
- if (txskb)
+ if (!txskb) {
+ /* local->mtx protects this */
+ local->roc_cookie_counter++;
+ roc->cookie = local->roc_cookie_counter;
+ /* wow, you wrapped 64 bits ... more likely a bug */
+ if (WARN_ON(roc->cookie == 0)) {
+ roc->cookie = 1;
+ local->roc_cookie_counter++;
+ }
+ *cookie = roc->cookie;
+ } else {
*cookie = (unsigned long)txskb;
- else
- *cookie = (unsigned long)roc;
+ }
return 0;
}
@@ -2423,7 +2432,7 @@
struct ieee80211_roc_work *dep, *tmp2;
list_for_each_entry_safe(dep, tmp2, &roc->dependents, list) {
- if (!mgmt_tx && (unsigned long)dep != cookie)
+ if (!mgmt_tx && dep->cookie != cookie)
continue;
else if (mgmt_tx && dep->mgmt_tx_cookie != cookie)
continue;
@@ -2435,7 +2444,7 @@
return 0;
}
- if (!mgmt_tx && (unsigned long)roc != cookie)
+ if (!mgmt_tx && roc->cookie != cookie)
continue;
else if (mgmt_tx && roc->mgmt_tx_cookie != cookie)
continue;