On 25/06/2020 09:54, Thomas Martitz wrote:
The eth_addr member is passed to ether_addr functions that require 2-byte alignment, therefore the member must be properly aligned to avoid unaligned accesses.
The problem is in place since the initial merge of multicast to unicast: commit 6db6f0eae6052b70885562e1733896647ec1d807 bridge: multicast to unicast
Fixes: 6db6f0eae605 ("bridge: multicast to unicast") Cc: Roopa Prabhu roopa@cumulusnetworks.com Cc: Nikolay Aleksandrov nikolay@cumulusnetworks.com Cc: David S. Miller davem@davemloft.net Cc: Jakub Kicinski kuba@kernel.org Cc: Felix Fietkau nbd@nbd.name Cc: stable@vger.kernel.org Signed-off-by: Thomas Martitz t.martitz@avm.de
net/bridge/br_private.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/net/bridge/br_private.h b/net/bridge/br_private.h index 7501be4eeba0..22cb2f1993ef 100644 --- a/net/bridge/br_private.h +++ b/net/bridge/br_private.h @@ -217,8 +217,8 @@ struct net_bridge_port_group { struct rcu_head rcu; struct timer_list timer; struct br_ip addr;
- unsigned char eth_addr[ETH_ALEN]; /* 2-byte aligned */ unsigned char flags;
- unsigned char eth_addr[ETH_ALEN];
}; struct net_bridge_mdb_entry {
Hi Thomas, To document it and guarantee that future struct changes won't break it I think it'd be a good idea to add __aligned(2) for that member instead of the comment.
Other than that the patch looks good.
Thanks, Nik