linux-stable/include/linux/bpf_lsm.h
KP Singh 423f16108c bpf: Augment the set of sleepable LSM hooks
Update the set of sleepable hooks with the ones that do not trigger
a warning with might_fault() when exercised with the correct kernel
config options enabled, i.e.

	DEBUG_ATOMIC_SLEEP=y
	LOCKDEP=y
	PROVE_LOCKING=y

This means that a sleepable LSM eBPF program can be attached to these
LSM hooks. A new helper method bpf_lsm_is_sleepable_hook is added and
the set is maintained locally in bpf_lsm.c

Signed-off-by: KP Singh <kpsingh@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20201113005930.541956-2-kpsingh@chromium.org
2020-11-13 15:45:54 +01:00

92 lines
2 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
/*
* Copyright (C) 2020 Google LLC.
*/
#ifndef _LINUX_BPF_LSM_H
#define _LINUX_BPF_LSM_H
#include <linux/sched.h>
#include <linux/bpf.h>
#include <linux/lsm_hooks.h>
#ifdef CONFIG_BPF_LSM
#define LSM_HOOK(RET, DEFAULT, NAME, ...) \
RET bpf_lsm_##NAME(__VA_ARGS__);
#include <linux/lsm_hook_defs.h>
#undef LSM_HOOK
struct bpf_storage_blob {
struct bpf_local_storage __rcu *storage;
};
extern struct lsm_blob_sizes bpf_lsm_blob_sizes;
int bpf_lsm_verify_prog(struct bpf_verifier_log *vlog,
const struct bpf_prog *prog);
bool bpf_lsm_is_sleepable_hook(u32 btf_id);
static inline struct bpf_storage_blob *bpf_inode(
const struct inode *inode)
{
if (unlikely(!inode->i_security))
return NULL;
return inode->i_security + bpf_lsm_blob_sizes.lbs_inode;
}
static inline struct bpf_storage_blob *bpf_task(
const struct task_struct *task)
{
if (unlikely(!task->security))
return NULL;
return task->security + bpf_lsm_blob_sizes.lbs_task;
}
extern const struct bpf_func_proto bpf_inode_storage_get_proto;
extern const struct bpf_func_proto bpf_inode_storage_delete_proto;
extern const struct bpf_func_proto bpf_task_storage_get_proto;
extern const struct bpf_func_proto bpf_task_storage_delete_proto;
void bpf_inode_storage_free(struct inode *inode);
void bpf_task_storage_free(struct task_struct *task);
#else /* !CONFIG_BPF_LSM */
static inline bool bpf_lsm_is_sleepable_hook(u32 btf_id)
{
return false;
}
static inline int bpf_lsm_verify_prog(struct bpf_verifier_log *vlog,
const struct bpf_prog *prog)
{
return -EOPNOTSUPP;
}
static inline struct bpf_storage_blob *bpf_inode(
const struct inode *inode)
{
return NULL;
}
static inline struct bpf_storage_blob *bpf_task(
const struct task_struct *task)
{
return NULL;
}
static inline void bpf_inode_storage_free(struct inode *inode)
{
}
static inline void bpf_task_storage_free(struct task_struct *task)
{
}
#endif /* CONFIG_BPF_LSM */
#endif /* _LINUX_BPF_LSM_H */