diff options
Diffstat (limited to 'net/core/dev.c')
| -rw-r--r-- | net/core/dev.c | 13 |
1 files changed, 12 insertions, 1 deletions
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) { |