bpf, cgroup: Fix cgroup struct_ops query for a second attach type

Two things in __cgroup_bpf_query() work only because CGROUP_TCP_SOCK_OPS is
the only struct_ops attach type.

It calls cgroup_bpf_enabled(atype) with an atype that
find_atype_by_struct_ops_id() works out at runtime.  That macro is an asm
goto and needs a constant.  Today the compiler can see there is only one
value; add a second type and the build breaks with "impossible constraint
in 'asm'".  The check is not needed anyway.  When the key is off nothing is
attached, so progs[atype] and effective[atype] are empty and the count loop
leaves total_cnt at 0.  The other attach types already use that loop with
no such check.  Drop the check and the skip_count label.

And find_atype_by_struct_ops_id() matches on type_id alone.  An attach type
whose subsystem is not built keeps type_id 0, so a query for type 0 finds
it and returns success with nothing instead of -ENOENT.  Skip such slots.

Fixes: 369d9dcd8fb8 ("bpf: Add infrastructure to support attaching struct_ops to cgroups")
Signed-off-by: Shakeel Butt <shakeel.butt@linux.dev>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Reviewed-by: Amery Hung <ameryhung@gmail.com>
Acked-by: Yafang Shao <laoar.shao@gmail.com>
Acked-by: Tejun Heo <tj@kernel.org>
Link: https://patch.msgid.link/20261001141901.3225830-1-shakeel.butt@linux.dev

0 files changed, 0 insertions, 0 deletions