path: root/net
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authorJohannes Berg <johannes.berg@intel.com>2015-12-01 23:15:26 +0100
committerJohannes Berg <johannes.berg@intel.com>2015-12-04 14:43:32 +0100
commit7d37fcd409199f76da522e6f6670a354ac468002 (patch)
tree6f645a02217b84c7b2a16147708a300985109f22 /net
parentmac80211_hwsim: stop using pointers as cookies (diff)
mac80211: reject zero cookie in mgmt-tx/roc cancel
When cancelling, you can cancel "any" (first in list) mgmt-tx or remain-on-channel operation by using the value 0 for the cookie along with the *opposite* operation, i.e. * cancel the first mgmt-tx by cancelling roc with 0 cookie * cancel the first roc by cancelling mgmt-tx with 0 cookie This isn't really that bad since userspace should only pass cookies that we gave it, but could lead to hard-to-debug issues so better prevent it and reject zero values since we never hand those out. Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Diffstat (limited to 'net')
1 files changed, 3 insertions, 0 deletions
diff --git a/net/mac80211/offchannel.c b/net/mac80211/offchannel.c
index cfd3356e26fd..6719b27aad66 100644
--- a/net/mac80211/offchannel.c
+++ b/net/mac80211/offchannel.c
@@ -697,6 +697,9 @@ static int ieee80211_cancel_roc(struct ieee80211_local *local,
struct ieee80211_roc_work *roc, *tmp, *found = NULL;
int ret;
+ if (!cookie)
+ return -ENOENT;
list_for_each_entry_safe(roc, tmp, &local->roc_list, list) {
if (!mgmt_tx && roc->cookie != cookie)