On Mon, Jul 6, 2020 at 4:02 PM Stanislav Fomichev <sdf@xxxxxxxxxx> wrote: > > Implement BPF_CGROUP_INET_SOCK_RELEASE hook that triggers > on inet socket release. It triggers only for userspace > sockets, the same semantics as existing BPF_CGROUP_INET_SOCK_CREATE. > > The only questionable part here is the sock->sk check > in the inet_release. Looking at the places where we > do 'sock->sk = NULL', I don't understand how it can race > with inet_release and why the check is there (it's been > there since the initial git import). Otherwise, the > change itself is pretty simple, we add a BPF hook > to the inet_release and avoid calling it for kernel > sockets. > > Signed-off-by: Stanislav Fomichev <sdf@xxxxxxxxxx> > --- > include/linux/bpf-cgroup.h | 4 ++++ > include/uapi/linux/bpf.h | 1 + > kernel/bpf/syscall.c | 3 +++ > net/core/filter.c | 1 + > net/ipv4/af_inet.c | 3 +++ > 5 files changed, 12 insertions(+) > Looks good overall, but I have no idea about sock->sk NULL case. Acked-by: Andrii Nakryiko <andriin@xxxxxx> > diff --git a/include/linux/bpf-cgroup.h b/include/linux/bpf-cgroup.h > index c66c545e161a..2c6f26670acc 100644 > --- a/include/linux/bpf-cgroup.h > +++ b/include/linux/bpf-cgroup.h [...]
