diff options
Diffstat (limited to 'kernel/bpf/cgroup.c')
-rw-r--r-- | kernel/bpf/cgroup.c | 67 |
1 files changed, 67 insertions, 0 deletions
diff --git a/kernel/bpf/cgroup.c b/kernel/bpf/cgroup.c index 3db5a17fcfe8..b789ab78d28f 100644 --- a/kernel/bpf/cgroup.c +++ b/kernel/bpf/cgroup.c @@ -522,3 +522,70 @@ int __cgroup_bpf_run_filter_sock_ops(struct sock *sk, return ret == 1 ? 0 : -EPERM; } EXPORT_SYMBOL(__cgroup_bpf_run_filter_sock_ops); + +int __cgroup_bpf_check_dev_permission(short dev_type, u32 major, u32 minor, + short access, enum bpf_attach_type type) +{ + struct cgroup *cgrp; + struct bpf_cgroup_dev_ctx ctx = { + .access_type = (access << 16) | dev_type, + .major = major, + .minor = minor, + }; + int allow = 1; + + rcu_read_lock(); + cgrp = task_dfl_cgroup(current); + allow = BPF_PROG_RUN_ARRAY(cgrp->bpf.effective[type], &ctx, + BPF_PROG_RUN); + rcu_read_unlock(); + + return !allow; +} +EXPORT_SYMBOL(__cgroup_bpf_check_dev_permission); + +static const struct bpf_func_proto * +cgroup_dev_func_proto(enum bpf_func_id func_id) +{ + switch (func_id) { + case BPF_FUNC_map_lookup_elem: + return &bpf_map_lookup_elem_proto; + case BPF_FUNC_map_update_elem: + return &bpf_map_update_elem_proto; + case BPF_FUNC_map_delete_elem: + return &bpf_map_delete_elem_proto; + case BPF_FUNC_get_current_uid_gid: + return &bpf_get_current_uid_gid_proto; + case BPF_FUNC_trace_printk: + if (capable(CAP_SYS_ADMIN)) + return bpf_get_trace_printk_proto(); + default: + return NULL; + } +} + +static bool cgroup_dev_is_valid_access(int off, int size, + enum bpf_access_type type, + struct bpf_insn_access_aux *info) +{ + if (type == BPF_WRITE) + return false; + + if (off < 0 || off + size > sizeof(struct bpf_cgroup_dev_ctx)) + return false; + /* The verifier guarantees that size > 0. */ + if (off % size != 0) + return false; + if (size != sizeof(__u32)) + return false; + + return true; +} + +const struct bpf_prog_ops cg_dev_prog_ops = { +}; + +const struct bpf_verifier_ops cg_dev_verifier_ops = { + .get_func_proto = cgroup_dev_func_proto, + .is_valid_access = cgroup_dev_is_valid_access, +}; |