diff options
Diffstat (limited to 'kernel/bpf/cgroup.c')
| -rw-r--r-- | kernel/bpf/cgroup.c | 47 |
1 files changed, 46 insertions, 1 deletions
diff --git a/kernel/bpf/cgroup.c b/kernel/bpf/cgroup.c index 9cf41dd4f96f..169cbd0de797 100644 --- a/kernel/bpf/cgroup.c +++ b/kernel/bpf/cgroup.c @@ -127,12 +127,57 @@ unsigned int __cgroup_bpf_run_lsm_current(const void *ctx, } #ifdef CONFIG_BPF_LSM +struct cgroup_lsm_atype { + u32 attach_btf_id; + int refcnt; +}; + +static struct cgroup_lsm_atype cgroup_lsm_atype[CGROUP_LSM_NUM]; + static enum cgroup_bpf_attach_type bpf_cgroup_atype_find(enum bpf_attach_type attach_type, u32 attach_btf_id) { + int i; + + lockdep_assert_held(&cgroup_mutex); + if (attach_type != BPF_LSM_CGROUP) return to_cgroup_bpf_attach_type(attach_type); - return CGROUP_LSM_START + bpf_lsm_hook_idx(attach_btf_id); + + for (i = 0; i < ARRAY_SIZE(cgroup_lsm_atype); i++) + if (cgroup_lsm_atype[i].attach_btf_id == attach_btf_id) + return CGROUP_LSM_START + i; + + for (i = 0; i < ARRAY_SIZE(cgroup_lsm_atype); i++) + if (cgroup_lsm_atype[i].attach_btf_id == 0) + return CGROUP_LSM_START + i; + + return -E2BIG; + +} + +void bpf_cgroup_atype_get(u32 attach_btf_id, int cgroup_atype) +{ + int i = cgroup_atype - CGROUP_LSM_START; + + lockdep_assert_held(&cgroup_mutex); + + WARN_ON_ONCE(cgroup_lsm_atype[i].attach_btf_id && + cgroup_lsm_atype[i].attach_btf_id != attach_btf_id); + + cgroup_lsm_atype[i].attach_btf_id = attach_btf_id; + cgroup_lsm_atype[i].refcnt++; +} + +void bpf_cgroup_atype_put(int cgroup_atype) +{ + int i = cgroup_atype - CGROUP_LSM_START; + + mutex_lock(&cgroup_mutex); + if (--cgroup_lsm_atype[i].refcnt <= 0) + cgroup_lsm_atype[i].attach_btf_id = 0; + WARN_ON_ONCE(cgroup_lsm_atype[i].refcnt < 0); + mutex_unlock(&cgroup_mutex); } #else static enum cgroup_bpf_attach_type |