diff options
Diffstat (limited to 'net')
| -rw-r--r-- | net/bpf/test_run.c | 3 | ||||
| -rw-r--r-- | net/core/dev.c | 10 | ||||
| -rw-r--r-- | net/core/filter.c | 41 |
3 files changed, 42 insertions, 12 deletions
diff --git a/net/bpf/test_run.c b/net/bpf/test_run.c index 2ced48662c1f..68c3578343b4 100644 --- a/net/bpf/test_run.c +++ b/net/bpf/test_run.c @@ -170,7 +170,8 @@ int bpf_prog_test_run_xdp(struct bpf_prog *prog, const union bpf_attr *kattr, xdp.rxq = &rxqueue->xdp_rxq; retval = bpf_test_run(prog, &xdp, repeat, &duration); - if (xdp.data != data + XDP_PACKET_HEADROOM + NET_IP_ALIGN) + if (xdp.data != data + XDP_PACKET_HEADROOM + NET_IP_ALIGN || + xdp.data_end != xdp.data + size) size = xdp.data_end - xdp.data; ret = bpf_test_finish(kattr, uattr, xdp.data, size, retval, duration); kfree(data); diff --git a/net/core/dev.c b/net/core/dev.c index a490ef643586..3e8ac127a7e1 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -3997,9 +3997,9 @@ static u32 netif_receive_generic_xdp(struct sk_buff *skb, struct bpf_prog *xdp_prog) { struct netdev_rx_queue *rxqueue; + void *orig_data, *orig_data_end; u32 metalen, act = XDP_DROP; struct xdp_buff xdp; - void *orig_data; int hlen, off; u32 mac_len; @@ -4038,6 +4038,7 @@ static u32 netif_receive_generic_xdp(struct sk_buff *skb, xdp.data_meta = xdp.data; xdp.data_end = xdp.data + hlen; xdp.data_hard_start = skb->data - skb_headroom(skb); + orig_data_end = xdp.data_end; orig_data = xdp.data; rxqueue = netif_get_rxqueue(skb); @@ -4052,6 +4053,13 @@ static u32 netif_receive_generic_xdp(struct sk_buff *skb, __skb_push(skb, -off); skb->mac_header += off; + /* check if bpf_xdp_adjust_tail was used. it can only "shrink" + * pckt. + */ + off = orig_data_end - xdp.data_end; + if (off != 0) + skb_set_tail_pointer(skb, xdp.data_end - xdp.data); + switch (act) { case XDP_REDIRECT: case XDP_TX: diff --git a/net/core/filter.c b/net/core/filter.c index a374b8560bc4..e25bc4a3aa1a 100644 --- a/net/core/filter.c +++ b/net/core/filter.c @@ -2694,20 +2694,13 @@ BPF_CALL_2(bpf_xdp_adjust_head, struct xdp_buff *, xdp, int, offset) { void *xdp_frame_end = xdp->data_hard_start + sizeof(struct xdp_frame); unsigned long metalen = xdp_get_metalen(xdp); - void *data_start = xdp->data_hard_start + metalen; + void *data_start = xdp_frame_end + metalen; void *data = xdp->data + offset; if (unlikely(data < data_start || data > xdp->data_end - ETH_HLEN)) return -EINVAL; - /* Avoid info leak, when reusing area prev used by xdp_frame */ - if (data < xdp_frame_end) { - unsigned long clearlen = xdp_frame_end - data; - - memset(data, 0, clearlen); - } - if (metalen) memmove(xdp->data_meta + offset, xdp->data_meta, metalen); @@ -2725,14 +2718,39 @@ static const struct bpf_func_proto bpf_xdp_adjust_head_proto = { .arg2_type = ARG_ANYTHING, }; +BPF_CALL_2(bpf_xdp_adjust_tail, struct xdp_buff *, xdp, int, offset) +{ + void *data_end = xdp->data_end + offset; + + /* only shrinking is allowed for now. */ + if (unlikely(offset >= 0)) + return -EINVAL; + + if (unlikely(data_end < xdp->data + ETH_HLEN)) + return -EINVAL; + + xdp->data_end = data_end; + + return 0; +} + +static const struct bpf_func_proto bpf_xdp_adjust_tail_proto = { + .func = bpf_xdp_adjust_tail, + .gpl_only = false, + .ret_type = RET_INTEGER, + .arg1_type = ARG_PTR_TO_CTX, + .arg2_type = ARG_ANYTHING, +}; + BPF_CALL_2(bpf_xdp_adjust_meta, struct xdp_buff *, xdp, int, offset) { + void *xdp_frame_end = xdp->data_hard_start + sizeof(struct xdp_frame); void *meta = xdp->data_meta + offset; unsigned long metalen = xdp->data - meta; if (xdp_data_meta_unsupported(xdp)) return -ENOTSUPP; - if (unlikely(meta < xdp->data_hard_start || + if (unlikely(meta < xdp_frame_end || meta > xdp->data)) return -EINVAL; if (unlikely((metalen & (sizeof(__u32) - 1)) || @@ -3074,7 +3092,8 @@ bool bpf_helper_changes_pkt_data(void *func) func == bpf_l4_csum_replace || func == bpf_xdp_adjust_head || func == bpf_xdp_adjust_meta || - func == bpf_msg_pull_data) + func == bpf_msg_pull_data || + func == bpf_xdp_adjust_tail) return true; return false; @@ -3888,6 +3907,8 @@ xdp_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) return &bpf_xdp_redirect_proto; case BPF_FUNC_redirect_map: return &bpf_xdp_redirect_map_proto; + case BPF_FUNC_xdp_adjust_tail: + return &bpf_xdp_adjust_tail_proto; default: return bpf_base_func_proto(func_id); } |