diff --git a/include/linux/filter.h b/include/linux/filter.h index ff698c9d1c94..1797e8506929 100644 --- a/include/linux/filter.h +++ b/include/linux/filter.h @@ -776,6 +776,10 @@ static inline u32 bpf_prog_run_clear_cb(const struct bpf_prog *prog, DECLARE_BPF_DISPATCHER(xdp) +DECLARE_STATIC_KEY_FALSE(bpf_master_redirect_enabled_key); + +u32 xdp_master_redirect(struct xdp_buff *xdp); + static __always_inline u32 bpf_prog_run_xdp(const struct bpf_prog *prog, struct xdp_buff *xdp) { @@ -783,7 +787,14 @@ static __always_inline u32 bpf_prog_run_xdp(const struct bpf_prog *prog, * under local_bh_disable(), which provides the needed RCU protection * for accessing map entries. */ - return __BPF_PROG_RUN(prog, xdp, BPF_DISPATCHER_FUNC(xdp)); + u32 act = __BPF_PROG_RUN(prog, xdp, BPF_DISPATCHER_FUNC(xdp)); + + if (static_branch_unlikely(&bpf_master_redirect_enabled_key)) { + if (act == XDP_TX && netif_is_bond_slave(xdp->rxq->dev)) + act = xdp_master_redirect(xdp); + } + + return act; } void bpf_prog_change_xdp(struct bpf_prog *prev_prog, struct bpf_prog *prog); diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h index d63a94ecbf3b..02c6e8e10c86 100644 --- a/include/linux/netdevice.h +++ b/include/linux/netdevice.h @@ -1330,6 +1330,9 @@ struct netdev_net_notifier { * that got dropped are freed/returned via xdp_return_frame(). * Returns negative number, means general error invoking ndo, meaning * no frames were xmit'ed and core-caller will free all frames. + * struct net_device *(*ndo_xdp_get_xmit_slave)(struct net_device *dev, + * struct xdp_buff *xdp); + * Get the xmit slave of master device based on the xdp_buff. * int (*ndo_xsk_wakeup)(struct net_device *dev, u32 queue_id, u32 flags); * This function is used to wake up the softirq, ksoftirqd or kthread * responsible for sending and/or receiving packets on a specific @@ -1557,6 +1560,8 @@ struct net_device_ops { int (*ndo_xdp_xmit)(struct net_device *dev, int n, struct xdp_frame **xdp, u32 flags); + struct net_device * (*ndo_xdp_get_xmit_slave)(struct net_device *dev, + struct xdp_buff *xdp); int (*ndo_xsk_wakeup)(struct net_device *dev, u32 queue_id, u32 flags); struct devlink_port * (*ndo_get_devlink_port)(struct net_device *dev); @@ -4087,6 +4092,7 @@ typedef int (*bpf_op_t)(struct net_device *dev, struct netdev_bpf *bpf); int dev_change_xdp_fd(struct net_device *dev, struct netlink_ext_ack *extack, int fd, int expected_fd, u32 flags); int bpf_xdp_link_attach(const union bpf_attr *attr, struct bpf_prog *prog); +u8 dev_xdp_prog_count(struct net_device *dev); u32 dev_xdp_prog_id(struct net_device *dev, enum bpf_xdp_mode mode); int __dev_forward_skb(struct net_device *dev, struct sk_buff *skb); diff --git a/net/core/dev.c b/net/core/dev.c index 64e1a5f63f93..9eb6dc9e02b3 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -9380,7 +9380,7 @@ static struct bpf_prog *dev_xdp_prog(struct net_device *dev, return dev->xdp_state[mode].prog; } -static u8 dev_xdp_prog_count(struct net_device *dev) +u8 dev_xdp_prog_count(struct net_device *dev) { u8 count = 0; int i; @@ -9390,6 +9390,7 @@ static u8 dev_xdp_prog_count(struct net_device *dev) count++; return count; } +EXPORT_SYMBOL_GPL(dev_xdp_prog_count); u32 dev_xdp_prog_id(struct net_device *dev, enum bpf_xdp_mode mode) { @@ -9483,6 +9484,8 @@ static int dev_xdp_attach(struct net_device *dev, struct netlink_ext_ack *extack { unsigned int num_modes = hweight32(flags & XDP_FLAGS_MODES); struct bpf_prog *cur_prog; + struct net_device *upper; + struct list_head *iter; enum bpf_xdp_mode mode; bpf_op_t bpf_op; int err; @@ -9521,6 +9524,14 @@ static int dev_xdp_attach(struct net_device *dev, struct netlink_ext_ack *extack return -EBUSY; } + /* don't allow if an upper device already has a program */ + netdev_for_each_upper_dev_rcu(dev, upper, iter) { + if (dev_xdp_prog_count(upper) > 0) { + NL_SET_ERR_MSG(extack, "Cannot attach when an upper device already has a program"); + return -EEXIST; + } + } + cur_prog = dev_xdp_prog(dev, mode); /* can't replace attached prog with link */ if (link && cur_prog) { diff --git a/net/core/filter.c b/net/core/filter.c index faf29fd82276..ff62cd39046d 100644 --- a/net/core/filter.c +++ b/net/core/filter.c @@ -3950,6 +3950,31 @@ void bpf_clear_redirect_map(struct bpf_map *map) } } +DEFINE_STATIC_KEY_FALSE(bpf_master_redirect_enabled_key); +EXPORT_SYMBOL_GPL(bpf_master_redirect_enabled_key); + +u32 xdp_master_redirect(struct xdp_buff *xdp) +{ + struct net_device *master, *slave; + struct bpf_redirect_info *ri = this_cpu_ptr(&bpf_redirect_info); + + master = netdev_master_upper_dev_get_rcu(xdp->rxq->dev); + slave = master->netdev_ops->ndo_xdp_get_xmit_slave(master, xdp); + if (slave && slave != xdp->rxq->dev) { + /* The target device is different from the receiving device, so + * redirect it to the new device. + * Using XDP_REDIRECT gets the correct behaviour from XDP enabled + * drivers to unmap the packet from their rx ring. + */ + ri->tgt_index = slave->ifindex; + ri->map_id = INT_MAX; + ri->map_type = BPF_MAP_TYPE_UNSPEC; + return XDP_REDIRECT; + } + return XDP_TX; +} +EXPORT_SYMBOL_GPL(xdp_master_redirect); + int xdp_do_redirect(struct net_device *dev, struct xdp_buff *xdp, struct bpf_prog *xdp_prog) {