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?
>
>> 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
>>
>>
