From b0706e5a21bb73b6e5c858ccc24eab53ee450a8b Mon Sep 17 00:00:00 2001

From: Stefan Assmann <sassmann@kpanic.de>

Date: Thu, 4 Mar 2021 10:34:30 +0100

Subject: [PATCH 7/7] i40e: improve locking of mac_filter_hash

Git-commit: 8b4b06919fd66caf49fdf4fe59f9d6312cf7956d

Patch-mainline: v5.15-rc1

References: git-fixes

i40e_config_vf_promiscuous_mode() calls

i40e_getnum_vf_vsi_vlan_filters() without acquiring the

mac_filter_hash_lock spinlock.

This is unsafe because mac_filter_hash may get altered in another thread

while i40e_getnum_vf_vsi_vlan_filters() traverses the hashes.

Simply adding the spinlock in i40e_getnum_vf_vsi_vlan_filters() is not

possible as it already gets called in i40e_get_vlan_list_sync() with the

spinlock held. Therefore adding a wrapper that acquires the spinlock and

call the correct function where appropriate.

Fixes: 37d318d7805f ("i40e: Remove scheduling while atomic possibility")

Fix-suggested-by: Paolo Abeni <pabeni@redhat.com>

Signed-off-by: Stefan Assmann <sassmann@kpanic.de>

Tested-by: Konrad Jankowski <konrad0.jankowski@intel.com>

Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>

Signed-off-by: Denis Kirjanov <denis.kirjanov@suse.com>

---

 drivers/net/ethernet/intel/i40e/i40e_virtchnl_pf.c | 23 +++++++++++++++++++---

 1 file changed, 20 insertions(+), 3 deletions(-)

diff --git a/drivers/net/ethernet/intel/i40e/i40e_virtchnl_pf.c b/drivers/net/ethernet/intel/i40e/i40e_virtchnl_pf.c

index ec133b017f6b..a166494d249a 100644

--- a/drivers/net/ethernet/intel/i40e/i40e_virtchnl_pf.c

+++ b/drivers/net/ethernet/intel/i40e/i40e_virtchnl_pf.c

@@ -1133,12 +1133,12 @@ static int i40e_quiesce_vf_pci(struct i40e_vf *vf)

 }

 /**

- * i40e_getnum_vf_vsi_vlan_filters

+ * __i40e_getnum_vf_vsi_vlan_filters

  * @vsi: pointer to the vsi

  *

  * called to get the number of VLANs offloaded on this VF

  **/

-static int i40e_getnum_vf_vsi_vlan_filters(struct i40e_vsi *vsi)

+static int __i40e_getnum_vf_vsi_vlan_filters(struct i40e_vsi *vsi)

 {

 	struct i40e_mac_filter *f;

 	u16 num_vlans = 0, bkt;

@@ -1151,6 +1151,23 @@ static int i40e_getnum_vf_vsi_vlan_filters(struct i40e_vsi *vsi)

 	return num_vlans;

 }

+/**

+ * i40e_getnum_vf_vsi_vlan_filters

+ * @vsi: pointer to the vsi

+ *

+ * wrapper for __i40e_getnum_vf_vsi_vlan_filters() with spinlock held

+ **/

+static int i40e_getnum_vf_vsi_vlan_filters(struct i40e_vsi *vsi)

+{

+	int num_vlans;

+

+	spin_lock_bh(&vsi->mac_filter_hash_lock);

+	num_vlans = __i40e_getnum_vf_vsi_vlan_filters(vsi);

+	spin_unlock_bh(&vsi->mac_filter_hash_lock);

+

+	return num_vlans;

+}

+

 /**

  * i40e_get_vlan_list_sync

  * @vsi: pointer to the VSI

@@ -1168,7 +1185,7 @@ static void i40e_get_vlan_list_sync(struct i40e_vsi *vsi, u16 *num_vlans,

 	int bkt;

 	spin_lock_bh(&vsi->mac_filter_hash_lock);

-	*num_vlans = i40e_getnum_vf_vsi_vlan_filters(vsi);

+	*num_vlans = __i40e_getnum_vf_vsi_vlan_filters(vsi);

 	*vlan_list = kcalloc(*num_vlans, sizeof(**vlan_list), GFP_ATOMIC);

 	if (!(*vlan_list))

 		goto err;

-- 

2.16.4