This is a note to let you know that I've just added the patch titled net: fix dev_fill_forward_path with pppoe + bridge to the 5.17-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-fix-dev_fill_forward_path-with-pppoe-bridge.patch and it can be found in the queue-5.17 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 74418e577755a8e710b5609b49222cfd6f31da4b Author: Felix Fietkau <nbd@xxxxxxxx> Date: Mon May 9 14:26:15 2022 +0200 net: fix dev_fill_forward_path with pppoe + bridge [ Upstream commit cf2df74e202d81b09f09d84c2d8903e0e87e9274 ] When calling dev_fill_forward_path on a pppoe device, the provided destination address is invalid. In order for the bridge fdb lookup to succeed, the pppoe code needs to update ctx->daddr to the correct value. Fix this by storing the address inside struct net_device_path_ctx Fixes: f6efc675c9dd ("net: ppp: resolve forwarding path for bridge pppoe devices") Signed-off-by: Felix Fietkau <nbd@xxxxxxxx> Signed-off-by: Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/drivers/net/ppp/pppoe.c b/drivers/net/ppp/pppoe.c index 3619520340b7..e172743948ed 100644 --- a/drivers/net/ppp/pppoe.c +++ b/drivers/net/ppp/pppoe.c @@ -988,6 +988,7 @@ static int pppoe_fill_forward_path(struct net_device_path_ctx *ctx, path->encap.proto = htons(ETH_P_PPP_SES); path->encap.id = be16_to_cpu(po->num); memcpy(path->encap.h_dest, po->pppoe_pa.remote, ETH_ALEN); + memcpy(ctx->daddr, po->pppoe_pa.remote, ETH_ALEN); path->dev = ctx->dev; ctx->dev = dev; diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h index f53ea7038441..dadd4d2f6d8a 100644 --- a/include/linux/netdevice.h +++ b/include/linux/netdevice.h @@ -891,7 +891,7 @@ struct net_device_path_stack { struct net_device_path_ctx { const struct net_device *dev; - const u8 *daddr; + u8 daddr[ETH_ALEN]; int num_vlans; struct { diff --git a/net/core/dev.c b/net/core/dev.c index 91cf709c98b3..5f1ac4812277 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -663,11 +663,11 @@ int dev_fill_forward_path(const struct net_device *dev, const u8 *daddr, const struct net_device *last_dev; struct net_device_path_ctx ctx = { .dev = dev, - .daddr = daddr, }; struct net_device_path *path; int ret = 0; + memcpy(ctx.daddr, daddr, sizeof(ctx.daddr)); stack->num_paths = 0; while (ctx.dev && ctx.dev->netdev_ops->ndo_fill_forward_path) { last_dev = ctx.dev;