From: Przemyslaw Patynowski <przemyslawx.patynowski@intel.com>
Date: Wed, 9 Mar 2022 16:37:39 +0100
Subject: iavf: Fix double free in iavf_reset_task
Patch-mainline: v5.17
Git-commit: 16b2dd8cdf6f4e0597c34899de74b4d012b78188
References: jsc#SLE-18385

Fix double free possibility in iavf_disable_vf, as crit_lock is
freed in caller, iavf_reset_task. Add kernel-doc for iavf_disable_vf.
Remove mutex_unlock in iavf_disable_vf.
Without this patch there is double free scenario, when calling
iavf_reset_task.

Fixes: e85ff9c631e1 ("iavf: Fix deadlock in iavf_reset_task")
Signed-off-by: Przemyslaw Patynowski <przemyslawx.patynowski@intel.com>
Suggested-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Mateusz Palczewski <mateusz.palczewski@intel.com>
Tested-by: Konrad Jankowski <konrad0.jankowski@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
 drivers/net/ethernet/intel/iavf/iavf_main.c |    8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

--- a/drivers/net/ethernet/intel/iavf/iavf_main.c
+++ b/drivers/net/ethernet/intel/iavf/iavf_main.c
@@ -2133,6 +2133,13 @@ restart_watchdog:
 		queue_delayed_work(iavf_wq, &adapter->watchdog_task, HZ * 2);
 }
 
+/**
+ * iavf_disable_vf - disable VF
+ * @adapter: board private structure
+ *
+ * Set communication failed flag and free all resources.
+ * NOTE: This function is expected to be called with crit_lock being held.
+ **/
 static void iavf_disable_vf(struct iavf_adapter *adapter)
 {
 	struct iavf_mac_filter *f, *ftmp;
@@ -2187,7 +2194,6 @@ static void iavf_disable_vf(struct iavf_
 	memset(adapter->vf_res, 0, IAVF_VIRTCHNL_VF_RESOURCE_SIZE);
 	iavf_shutdown_adminq(&adapter->hw);
 	adapter->netdev->flags &= ~IFF_UP;
-	mutex_unlock(&adapter->crit_lock);
 	adapter->flags &= ~IAVF_FLAG_RESET_PENDING;
 	iavf_change_state(adapter, __IAVF_DOWN);
 	wake_up(&adapter->down_waitqueue);