Patch "sfc: don't read beyond unicast address list" has been added to the 4.12-stable tree

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

sfc: don't read beyond unicast address list

to the 4.12-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:
sfc-don-t-read-beyond-unicast-address-list.patch
and it can be found in the queue-4.12 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.

From: Bert Kenward <[email protected]>
Date: Wed, 12 Jul 2017 17:19:41 +0100
Subject: sfc: don't read beyond unicast address list

From: Bert Kenward <[email protected]>

[ Upstream commit c70d68150f71b84cea6997a53493e17bf18a54db ]

If we have more than 32 unicast MAC addresses assigned to an interface we will read beyond the end of the address table in the driver when adding filters. The next 256 entries store multicast addresses, so we will end up attempting to insert duplicate filters, which is mostly harmless. If we add more than 288 unicast addresses we will then read past the multicast address table, which is likely to be more exciting.

---
 drivers/net/ethernet/sfc/ef10.c |    8 +++-----
 1 file changed, 3 insertions(+), 5 deletions(-)

@@ -5034,12 +5034,9 @@ static void efx_ef10_filter_uc_addr_list
 	struct efx_ef10_filter_table *table = efx->filter_state;
 	struct net_device *net_dev = efx->net_dev;
 	struct netdev_hw_addr *uc;
-	int addr_count;
 	unsigned int i;
 
-	addr_count = netdev_uc_count(net_dev);
 	table->uc_promisc = !!(net_dev->flags & IFF_PROMISC);
-	table->dev_uc_count = 1 + addr_count;
 	ether_addr_copy(table->dev_uc_list[0].addr, net_dev->dev_addr);
 	i = 1;
 	netdev_for_each_uc_addr(uc, net_dev) {

@@ -5050,6 +5047,8 @@ static void efx_ef10_filter_uc_addr_list
 		ether_addr_copy(table->dev_uc_list[i].addr, uc->addr);
 		i++;
 	}
+
+	table->dev_uc_count = i;
 }
 
 static void efx_ef10_filter_mc_addr_list(struct efx_nic *efx)

@@ -5057,12 +5056,11 @@ static void efx_ef10_filter_mc_addr_list
 	struct efx_ef10_filter_table *table = efx->filter_state;
 	struct net_device *net_dev = efx->net_dev;
 	struct netdev_hw_addr *mc;
-	unsigned int i, addr_count;
+	unsigned int i;
 
 	table->mc_overflow = false;
 	table->mc_promisc = !!(net_dev->flags & (IFF_PROMISC | IFF_ALLMULTI));
 
-	addr_count = netdev_mc_count(net_dev);
 	i = 0;
 	netdev_for_each_mc_addr(mc, net_dev) {
 		if (i >= EFX_EF10_FILTER_DEV_MC_MAX) {

Patches currently in stable-queue which might be from [email protected] are

queue-4.12/sfc-don-t-read-beyond-unicast-address-list.patch