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| author | Jesper Dangaard Brouer <brouer@redhat.com> | 2020-05-14 12:51:35 +0200 |
|---|---|---|
| committer | Alexei Starovoitov <ast@kernel.org> | 2020-05-14 21:21:56 -0700 |
| commit | bc56c919fce782f616823b76fb70a788f4762cf5 (patch) | |
| tree | eaeac8cc29065dac36ceda034db0a102dfd4605b | |
| parent | ddb47d518ca10948d1f64a983cb9274720f691cd (diff) | |
| download | linux-bc56c919fce782f616823b76fb70a788f4762cf5.tar.gz linux-bc56c919fce782f616823b76fb70a788f4762cf5.tar.bz2 linux-bc56c919fce782f616823b76fb70a788f4762cf5.zip | |
bpf: Add xdp.frame_sz in bpf_prog_test_run_xdp().
Update the memory requirements, when adding xdp.frame_sz in BPF test_run
function bpf_prog_test_run_xdp() which e.g. is used by XDP selftests.
Specifically add the expected reserved tailroom, but also allocated a
larger memory area to reflect that XDP frames usually comes in this
format. Limit the provided packet data size to 4096 minus headroom +
tailroom, as this also reflect a common 3520 bytes MTU limit with XDP.
Note that bpf_test_init already use a memory allocation method that clears
memory. Thus, this already guards against leaking uninit kernel memory.
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/158945349549.97035.15316291762482444006.stgit@firesoul
| -rw-r--r-- | net/bpf/test_run.c | 16 |
1 files changed, 12 insertions, 4 deletions
diff --git a/net/bpf/test_run.c b/net/bpf/test_run.c index 29dbdd4c29f6..30ba7d38941d 100644 --- a/net/bpf/test_run.c +++ b/net/bpf/test_run.c @@ -470,25 +470,34 @@ out: int bpf_prog_test_run_xdp(struct bpf_prog *prog, const union bpf_attr *kattr, union bpf_attr __user *uattr) { + u32 tailroom = SKB_DATA_ALIGN(sizeof(struct skb_shared_info)); + u32 headroom = XDP_PACKET_HEADROOM; u32 size = kattr->test.data_size_in; u32 repeat = kattr->test.repeat; struct netdev_rx_queue *rxqueue; struct xdp_buff xdp = {}; u32 retval, duration; + u32 max_data_sz; void *data; int ret; if (kattr->test.ctx_in || kattr->test.ctx_out) return -EINVAL; - data = bpf_test_init(kattr, size, XDP_PACKET_HEADROOM + NET_IP_ALIGN, 0); + /* XDP have extra tailroom as (most) drivers use full page */ + max_data_sz = 4096 - headroom - tailroom; + if (size > max_data_sz) + return -EINVAL; + + data = bpf_test_init(kattr, max_data_sz, headroom, tailroom); if (IS_ERR(data)) return PTR_ERR(data); xdp.data_hard_start = data; - xdp.data = data + XDP_PACKET_HEADROOM + NET_IP_ALIGN; + xdp.data = data + headroom; xdp.data_meta = xdp.data; xdp.data_end = xdp.data + size; + xdp.frame_sz = headroom + max_data_sz + tailroom; rxqueue = __netif_get_rx_queue(current->nsproxy->net_ns->loopback_dev, 0); xdp.rxq = &rxqueue->xdp_rxq; @@ -496,8 +505,7 @@ int bpf_prog_test_run_xdp(struct bpf_prog *prog, const union bpf_attr *kattr, ret = bpf_test_run(prog, &xdp, repeat, &retval, &duration, true); if (ret) goto out; - if (xdp.data != data + XDP_PACKET_HEADROOM + NET_IP_ALIGN || - xdp.data_end != xdp.data + size) + if (xdp.data != data + headroom || xdp.data_end != xdp.data + size) size = xdp.data_end - xdp.data; ret = bpf_test_finish(kattr, uattr, xdp.data, size, retval, duration); out: |