Patch "net: macsec: fix net device access prior to holding a lock" has been added to the 6.0-stable tree

[Sasha Levin <sashal@xxxxxxxxxx>]

This is a note to let you know that I've just added the patch titled

    net: macsec: fix net device access prior to holding a lock

to the 6.0-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     net-macsec-fix-net-device-access-prior-to-holding-a-.patch
and it can be found in the queue-6.0 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.



commit 3bd17ec683a6178f656a454db0813b65e8886326
Author: Emeel Hakim <ehakim@xxxxxxxxxx>
Date:   Sun Dec 11 09:55:32 2022 +0200

    net: macsec: fix net device access prior to holding a lock
    
    [ Upstream commit f3b4a00f0f62da252c598310698dfc82ef2f2e2e ]
    
    Currently macsec offload selection update routine accesses
    the net device prior to holding the relevant lock.
    Fix by holding the lock prior to the device access.
    
    Fixes: dcb780fb2795 ("net: macsec: add nla support for changing the offloading selection")
    Reviewed-by: Raed Salem <raeds@xxxxxxxxxx>
    Signed-off-by: Emeel Hakim <ehakim@xxxxxxxxxx>
    Link: https://lore.kernel.org/r/20221211075532.28099-1-ehakim@xxxxxxxxxx
    Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx>
    Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>

diff --git a/drivers/net/macsec.c b/drivers/net/macsec.c
index 8dafc814282c..022b2daabd74 100644
--- a/drivers/net/macsec.c
+++ b/drivers/net/macsec.c
@@ -2621,7 +2621,7 @@ static int macsec_upd_offload(struct sk_buff *skb, struct genl_info *info)
 	const struct macsec_ops *ops;
 	struct macsec_context ctx;
 	struct macsec_dev *macsec;
-	int ret;
+	int ret = 0;
 
 	if (!attrs[MACSEC_ATTR_IFINDEX])
 		return -EINVAL;
@@ -2634,28 +2634,36 @@ static int macsec_upd_offload(struct sk_buff *skb, struct genl_info *info)
 					macsec_genl_offload_policy, NULL))
 		return -EINVAL;
 
+	rtnl_lock();
+
 	dev = get_dev_from_nl(genl_info_net(info), attrs);
-	if (IS_ERR(dev))
-		return PTR_ERR(dev);
+	if (IS_ERR(dev)) {
+		ret = PTR_ERR(dev);
+		goto out;
+	}
 	macsec = macsec_priv(dev);
 
-	if (!tb_offload[MACSEC_OFFLOAD_ATTR_TYPE])
-		return -EINVAL;
+	if (!tb_offload[MACSEC_OFFLOAD_ATTR_TYPE]) {
+		ret = -EINVAL;
+		goto out;
+	}
 
 	offload = nla_get_u8(tb_offload[MACSEC_OFFLOAD_ATTR_TYPE]);
 	if (macsec->offload == offload)
-		return 0;
+		goto out;
 
 	/* Check if the offloading mode is supported by the underlying layers */
 	if (offload != MACSEC_OFFLOAD_OFF &&
-	    !macsec_check_offload(offload, macsec))
-		return -EOPNOTSUPP;
+	    !macsec_check_offload(offload, macsec)) {
+		ret = -EOPNOTSUPP;
+		goto out;
+	}
 
 	/* Check if the net device is busy. */
-	if (netif_running(dev))
-		return -EBUSY;
-
-	rtnl_lock();
+	if (netif_running(dev)) {
+		ret = -EBUSY;
+		goto out;
+	}
 
 	prev_offload = macsec->offload;
 	macsec->offload = offload;
@@ -2690,7 +2698,7 @@ static int macsec_upd_offload(struct sk_buff *skb, struct genl_info *info)
 
 rollback:
 	macsec->offload = prev_offload;
-
+out:
 	rtnl_unlock();
 	return ret;
 }