wifi: cfg80211: cancel wiphy_work before freeing wiphy

[ Upstream commit 72d520476a2fab6f3489e8388ab524985d6c4b90 ]

A wiphy_work can be queued from the moment the wiphy is allocated and
initialized (i.e. wiphy_new_nm). When a wiphy_work is queued, the
rdev::wiphy_work is getting queued.

If wiphy_free is called before the rdev::wiphy_work had a chance to run,
the wiphy memory will be freed, and then when it eventally gets to run
it'll use invalid memory.

Fix this by canceling the work before freeing the wiphy.

Fixes: a3ee4dc84c4e ("wifi: cfg80211: add a work abstraction with special semantics")
Signed-off-by: Miri Korenblit <miriam.rachel.korenblit@intel.com>
Reviewed-by: Johannes Berg <johannes.berg@intel.com>
Link: https://patch.msgid.link/20250306123626.efd1d19f6e07.I48229f96f4067ef73f5b87302335e2fd750136c9@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/net/wireless/core.c b/net/wireless/core.c
index 7d313fb66d76ba5b21038bb9b0316f5df375cddd..1ce8fff2a28a4ec16453b44b79b6b1dbc7628c78 100644 (file)
--- a/net/wireless/core.c
+++ b/net/wireless/core.c
@@ -1198,6 +1198,13 @@ void cfg80211_dev_free(struct cfg80211_registered_device *rdev)
 {
        struct cfg80211_internal_bss *scan, *tmp;
        struct cfg80211_beacon_registration *reg, *treg;
+       unsigned long flags;
+
+       spin_lock_irqsave(&rdev->wiphy_work_lock, flags);
+       WARN_ON(!list_empty(&rdev->wiphy_work_list));
+       spin_unlock_irqrestore(&rdev->wiphy_work_lock, flags);
+       cancel_work_sync(&rdev->wiphy_work);
+
        rfkill_destroy(rdev->wiphy.rfkill);
        list_for_each_entry_safe(reg, treg, &rdev->beacon_registrations, list) {
                list_del(&reg->list);