> On Oct 18, 2018, at 10:22 PM, Eric Dumazet <eric.duma...@gmail.com> wrote:
>
>
>
> On 10/18/2018 10:01 PM, Song Liu wrote:
>> Tests are added to make sure CGROUP_SKB cannot access:
>> tc_classid, data_meta, flow_keys
>>
>> and can read and write:
>> mark, prority, and cb[0-4]
>>
>> and can read other fields.
>>
>> To make selftest with skb->sk work, a dummy sk is added in
>> bpf_prog_test_run_skb().
>>
>> Signed-off-by: Song Liu <songliubrav...@fb.com>
>> ---
>> net/bpf/test_run.c | 7 +
>> tools/testing/selftests/bpf/test_verifier.c | 171 ++++++++++++++++++++
>> 2 files changed, 178 insertions(+)
>>
>> diff --git a/net/bpf/test_run.c b/net/bpf/test_run.c
>> index 0c423b8cd75c..8dccac305268 100644
>> --- a/net/bpf/test_run.c
>> +++ b/net/bpf/test_run.c
>> @@ -10,6 +10,8 @@
>> #include <linux/etherdevice.h>
>> #include <linux/filter.h>
>> #include <linux/sched/signal.h>
>> +#include <net/sock.h>
>> +#include <net/tcp.h>
>>
>> static __always_inline u32 bpf_test_run_one(struct bpf_prog *prog, void *ctx,
>> struct bpf_cgroup_storage *storage[MAX_BPF_CGROUP_STORAGE_TYPE])
>> @@ -115,6 +117,7 @@ int bpf_prog_test_run_skb(struct bpf_prog *prog, const
>> union bpf_attr *kattr,
>> u32 retval, duration;
>> int hh_len = ETH_HLEN;
>> struct sk_buff *skb;
>> + struct sock sk = {0};
>
> Arg another dummy :/
>
>> void *data;
>> int ret;
>>
>> @@ -137,11 +140,15 @@ int bpf_prog_test_run_skb(struct bpf_prog *prog, const
>> union bpf_attr *kattr,
>> break;
>> }
>>
>> + sock_net_set(&sk, &init_net);
>
> A few lines later we use :
>
> skb->protocol = eth_type_trans(skb, current->nsproxy->net_ns->loopback_dev);
>
> So it looks like you want instead for consistency :
>
> sock_net_set(&sk, current->nsproxy->net_ns);
Thanks! Will fix this in v6.
>
>
>> + sock_init_data(NULL, &sk);
>> +
>> skb = build_skb(data, 0);
>> if (!skb) {
>> kfree(data);
>> return -ENOMEM;
>> }
>> + skb->sk = &sk;
>>
>
> Normally this would need a skb->destructor, but I guess nothing will call
> skb_orphan()
> from this point.
Yeah, I double checked, this should be OK.
Song
