bpf: Allow bpf_{s,g}etsockopt from cgroup bind{4,6} hooks

mainline inclusion
from mainline-v5.11-rc1
commit 427167c0
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I4GII8?from=project-issue


CVE: NA

---------

I have to now lock/unlock socket for the bind hook execution.
That shouldn't cause any overhead because the socket is unbound
and shouldn't receive any traffic.

Signed-off-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrey Ignatov <rdna@fb.com>
Link: https://lore.kernel.org/bpf/20201202172516.3483656-3-sdf@google.com


Signed-off-by: Lu Jialin <lujialin4@huawei.com>
Reviewed-by: Wei <Yongjun&lt;weiyongjun1@huawei.com>
Reviewed-by: weiyang wang <wangweiyang2@huawei.com>
Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com>