diff options
Diffstat (limited to 'kernel/bpf/helpers.c')
| -rw-r--r-- | kernel/bpf/helpers.c | 21 |
1 files changed, 20 insertions, 1 deletions
diff --git a/kernel/bpf/helpers.c b/kernel/bpf/helpers.c index da2681ebb7c3..2299bb0d89e5 100644 --- a/kernel/bpf/helpers.c +++ b/kernel/bpf/helpers.c @@ -1959,6 +1959,25 @@ struct cgroup *bpf_cgroup_ancestor(struct cgroup *cgrp, int level) } #endif /* CONFIG_CGROUPS */ +/** + * bpf_task_from_pid - Find a struct task_struct from its pid by looking it up + * in the root pid namespace idr. If a task is returned, it must either be + * stored in a map, or released with bpf_task_release(). + * @pid: The pid of the task being looked up. + */ +struct task_struct *bpf_task_from_pid(s32 pid) +{ + struct task_struct *p; + + rcu_read_lock(); + p = find_task_by_pid_ns(pid, &init_pid_ns); + if (p) + bpf_task_acquire(p); + rcu_read_unlock(); + + return p; +} + void *bpf_cast_to_kern_ctx(void *obj) { return obj; @@ -1984,13 +2003,13 @@ BTF_ID_FLAGS(func, bpf_list_pop_back, KF_ACQUIRE | KF_RET_NULL) BTF_ID_FLAGS(func, bpf_task_acquire, KF_ACQUIRE | KF_TRUSTED_ARGS) BTF_ID_FLAGS(func, bpf_task_kptr_get, KF_ACQUIRE | KF_KPTR_GET | KF_RET_NULL) BTF_ID_FLAGS(func, bpf_task_release, KF_RELEASE) - #ifdef CONFIG_CGROUPS BTF_ID_FLAGS(func, bpf_cgroup_acquire, KF_ACQUIRE | KF_TRUSTED_ARGS) BTF_ID_FLAGS(func, bpf_cgroup_kptr_get, KF_ACQUIRE | KF_KPTR_GET | KF_RET_NULL) BTF_ID_FLAGS(func, bpf_cgroup_release, KF_RELEASE) BTF_ID_FLAGS(func, bpf_cgroup_ancestor, KF_ACQUIRE | KF_TRUSTED_ARGS | KF_RET_NULL) #endif +BTF_ID_FLAGS(func, bpf_task_from_pid, KF_ACQUIRE | KF_RET_NULL) BTF_SET8_END(generic_btf_ids) static const struct btf_kfunc_id_set generic_kfunc_set = { |