On 2019/7/3 0:04, Yonghong Song wrote:
>
>
> On 7/2/19 8:53 AM, Stanislav Fomichev wrote:
>> On 07/02, YueHaibing wrote:
>>> If CONFIG_NET is not set, gcc building fails:
>>>
>>> kernel/bpf/cgroup.o: In function `cg_sockopt_func_proto':
>>> cgroup.c:(.text+0x237e): undefined reference to `bpf_sk_storage_get_proto'
>>> cgroup.c:(.text+0x2394): undefined reference to `bpf_sk_storage_delete_proto'
>>> kernel/bpf/cgroup.o: In function `__cgroup_bpf_run_filter_getsockopt':
>>> (.text+0x2a1f): undefined reference to `lock_sock_nested'
>>> (.text+0x2ca2): undefined reference to `release_sock'
>>> kernel/bpf/cgroup.o: In function `__cgroup_bpf_run_filter_setsockopt':
>>> (.text+0x3006): undefined reference to `lock_sock_nested'
>>> (.text+0x32bb): undefined reference to `release_sock'
>>>
>>> Add CONFIG_NET dependency to fix this.
>> Can you share the config? Do I understand correctly that you have
>> CONFIG_NET=n and CONFIG_BPF=y? What parts of BPF do you expect to
>> work in this case?
>>
>> Less invasive fix would be something along the lines:
>>
>> diff --git a/kernel/bpf/cgroup.c b/kernel/bpf/cgroup.c
>> index 76fa0076f20d..0a00eaca6fae 100644
>> --- a/kernel/bpf/cgroup.c
>> +++ b/kernel/bpf/cgroup.c
>> @@ -939,6 +939,7 @@ int __cgroup_bpf_run_filter_sysctl(struct ctl_table_header *head,
>> }
>> EXPORT_SYMBOL(__cgroup_bpf_run_filter_sysctl);
>>
>> +#ifdef CONFIG_NET
>> static bool __cgroup_bpf_prog_array_is_empty(struct cgroup *cgrp,
>> enum bpf_attach_type attach_type)
>> {
>> @@ -1120,6 +1121,7 @@ int __cgroup_bpf_run_filter_getsockopt(struct sock *sk, int level,
>> return ret;
>> }
>> EXPORT_SYMBOL(__cgroup_bpf_run_filter_getsockopt);
>> +#endif
>>
>> static ssize_t sysctl_cpy_dir(const struct ctl_dir *dir, char **bufp,
>> size_t *lenp)
>> @@ -1386,10 +1388,12 @@ static const struct bpf_func_proto *
>> cg_sockopt_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
>> {
>> switch (func_id) {
>> +#ifdef CONFIG_NET
>> case BPF_FUNC_sk_storage_get:
>> return &bpf_sk_storage_get_proto;
>> case BPF_FUNC_sk_storage_delete:
>> return &bpf_sk_storage_delete_proto;
>> +#endif
>> #ifdef CONFIG_INET
>> case BPF_FUNC_tcp_sock:
>> return &bpf_tcp_sock_proto;
>
> Ah. Just send another email without checking inbox.
> Looks like the above change is preferred.
> YueHaibing, could you make change and resubmit your patch?
Sure, I will test and resubmit it.
>
>>
>>> Reported-by: Hulk Robot <hulkci@xxxxxxxxxx>
>>> Fixes: 0d01da6afc54 ("bpf: implement getsockopt and setsockopt hooks")
>>> Signed-off-by: YueHaibing <yuehaibing@xxxxxxxxxx>
>>> ---
>>> init/Kconfig | 1 +
>>> 1 file changed, 1 insertion(+)
>>>
>>> diff --git a/init/Kconfig b/init/Kconfig
>>> index e2e51b5..341cf2a 100644
>>> --- a/init/Kconfig
>>> +++ b/init/Kconfig
>>> @@ -998,6 +998,7 @@ config CGROUP_PERF
>>> config CGROUP_BPF
>>> bool "Support for eBPF programs attached to cgroups"
>>> depends on BPF_SYSCALL
>>> + depends on NET
>>> select SOCK_CGROUP_DATA
>>> help
>>> Allow attaching eBPF programs to a cgroup using the bpf(2)
>>> --
>>> 2.7.4
>>>
>>>
