From: Avraham Stern <avraham.stern@xxxxxxxxx>
If cfg80211_pmsr_process_abort() moves all the PMSR requests that
need to be freed into a local list before aborting and freeing them.
As a result, it is possible that cfg80211_pmsr_complete() will run in
parallel and free the same PMSR request.
Fix it by freeing the request in cfg80211_pmsr_complete() only if it
is still in the original pmsr list.
Signed-off-by: Avraham Stern <avraham.stern@xxxxxxxxx>
Signed-off-by: Luca Coelho <luciano.coelho@xxxxxxxxx>
---
net/wireless/pmsr.c | 16 ++++++++++++++--
1 file changed, 14 insertions(+), 2 deletions(-)
diff --git a/net/wireless/pmsr.c b/net/wireless/pmsr.c
index 6bdd96408022..d245968b74cb 100644
--- a/net/wireless/pmsr.c
+++ b/net/wireless/pmsr.c
@@ -334,6 +334,7 @@ void cfg80211_pmsr_complete(struct wireless_dev *wdev,
gfp_t gfp)
{
struct cfg80211_registered_device *rdev = wiphy_to_rdev(wdev->wiphy);
+ struct cfg80211_pmsr_request *tmp, *prev, *to_free = NULL;
struct sk_buff *msg;
void *hdr;
@@ -364,9 +365,20 @@ void cfg80211_pmsr_complete(struct wireless_dev *wdev,
nlmsg_free(msg);
free_request:
spin_lock_bh(&wdev->pmsr_lock);
- list_del(&req->list);
+ /*
+ * cfg80211_pmsr_process_abort() may have already moved this request
+ * to the free list, and will free it later. In this case, don't free
+ * it here.
+ */
+ list_for_each_entry_safe(tmp, prev, &wdev->pmsr_list, list) {
+ if (tmp == req) {
+ list_del(&req->list);
+ to_free = req;
+ break;
+ }
+ }
spin_unlock_bh(&wdev->pmsr_lock);
- kfree(req);
+ kfree(to_free);
}
EXPORT_SYMBOL_GPL(cfg80211_pmsr_complete);
--
2.32.0
