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