Netdev Archive on lore.kernel.org
help / color / mirror / Atom feed
From: Tony Nguyen <anthony.l.nguyen@intel.com>
To: davem@davemloft.net, kuba@kernel.org
Cc: Stefan Assmann <sassmann@kpanic.de>,
	netdev@vger.kernel.org, anthony.l.nguyen@intel.com,
	Paolo Abeni <pabeni@redhat.com>,
	Konrad Jankowski <konrad0.jankowski@intel.com>
Subject: [PATCH net-next 1/3] i40e: improve locking of mac_filter_hash
Date: Mon, 19 Jul 2021 09:31:52 -0700	[thread overview]
Message-ID: <20210719163154.986679-2-anthony.l.nguyen@intel.com> (raw)
In-Reply-To: <20210719163154.986679-1-anthony.l.nguyen@intel.com>

From: Stefan Assmann <sassmann@kpanic.de>

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>
---
 .../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 eff0a30790dd..472f56b360b8 100644
--- a/drivers/net/ethernet/intel/i40e/i40e_virtchnl_pf.c
+++ b/drivers/net/ethernet/intel/i40e/i40e_virtchnl_pf.c
@@ -1160,12 +1160,12 @@ 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;
@@ -1178,6 +1178,23 @@ 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
@@ -1195,7 +1212,7 @@ 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;
-- 
2.26.2


  reply	other threads:[~2021-07-19 16:36 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-07-19 16:31 [PATCH net-next 0/3][pull request] 40GbE Intel Wired LAN Driver Updates 2021-07-19 Tony Nguyen
2021-07-19 16:31 ` Tony Nguyen [this message]
2021-07-19 16:31 ` [PATCH net-next 2/3] iavf: do not override the adapter state in the watchdog task Tony Nguyen
2021-07-19 16:31 ` [PATCH net-next 3/3] iavf: fix locking of critical sections Tony Nguyen
2021-07-20 11:31   ` Jakub Kicinski
2021-07-20 12:03     ` Stefan Assmann
2021-07-20 13:30 ` [PATCH net-next 0/3][pull request] 40GbE Intel Wired LAN Driver Updates 2021-07-19 patchwork-bot+netdevbpf

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20210719163154.986679-2-anthony.l.nguyen@intel.com \
    --to=anthony.l.nguyen@intel.com \
    --cc=davem@davemloft.net \
    --cc=konrad0.jankowski@intel.com \
    --cc=kuba@kernel.org \
    --cc=netdev@vger.kernel.org \
    --cc=pabeni@redhat.com \
    --cc=sassmann@kpanic.de \
    --subject='Re: [PATCH net-next 1/3] i40e: improve locking of mac_filter_hash' \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).