If net_prio is used, we could also use eBPF programs to attach it, because the net_prio cgroup could be got with prioidx in struct sock_cgroup_data. Hence it should not only be limited to cgroup2.
Signed-off-by: Yafang Shao <laoar.s...@gmail.com> --- include/linux/cgroup.h | 18 ++++++++++++++++-- kernel/cgroup/cgroup.c | 6 +----- 2 files changed, 17 insertions(+), 7 deletions(-) diff --git a/include/linux/cgroup.h b/include/linux/cgroup.h index 473e0c0..1d67def 100644 --- a/include/linux/cgroup.h +++ b/include/linux/cgroup.h @@ -772,8 +772,22 @@ static inline struct cgroup *sock_cgroup_ptr(struct sock_cgroup_data *skcd) */ v = READ_ONCE(skcd->val); - if (v & 1) - return &cgrp_dfl_root.cgrp; + /* either net_prio or net_cls or both being used. */ + if (v & 1) { + if (skcd->prioidx != 1) { + struct cgroup_subsys_state *css; + struct cgroup *cg; + + rcu_read_lock(); + css = css_from_id(skcd->prioidx, &net_prio_cgrp_subsys); + cg = css->cgroup; + rcu_read_unlock(); + + return cg; + } + + return task_cgroup(current, net_prio_cgrp_id); + } return (struct cgroup *)(unsigned long)v ?: &cgrp_dfl_root.cgrp; #else diff --git a/kernel/cgroup/cgroup.c b/kernel/cgroup/cgroup.c index 7e4c445..59610f5 100644 --- a/kernel/cgroup/cgroup.c +++ b/kernel/cgroup/cgroup.c @@ -5735,7 +5735,7 @@ struct cgroup *cgroup_get_from_path(const char *path) /** * cgroup_get_from_fd - get a cgroup pointer from a fd - * @fd: fd obtained by open(cgroup2_dir) + * @fd: fd obtained by open(cgroup2_dir or net_prio_dir) * * Find the cgroup from a fd which should be obtained * by opening a cgroup directory. Returns a pointer to the @@ -5758,10 +5758,6 @@ struct cgroup *cgroup_get_from_fd(int fd) return ERR_CAST(css); cgrp = css->cgroup; - if (!cgroup_on_dfl(cgrp)) { - cgroup_put(cgrp); - return ERR_PTR(-EBADF); - } return cgrp; } -- 1.8.3.1