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Linux kernel mirror (for testing) git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
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#ifndef _SECURITY_LANDLOCK_OBJECT_H#define _SECURITY_LANDLOCK_OBJECT_H
#include <linux/compiler_types.h>#include <linux/refcount.h>#include <linux/spinlock.h>
struct landlock_object;
/** * struct landlock_object_underops - Operations on an underlying object */struct landlock_object_underops { /** * @release: Releases the underlying object (e.g. iput() for an inode). */ void (*release)(struct landlock_object *const object) __releases(object->lock);};
/** * struct landlock_object - Security blob tied to a kernel object * * The goal of this structure is to enable to tie a set of ephemeral access * rights (pertaining to different domains) to a kernel object (e.g an inode) * in a safe way. This implies to handle concurrent use and modification. * * The lifetime of a &struct landlock_object depends on the rules referring to * it. */struct landlock_object { /** * @usage: This counter is used to tie an object to the rules matching * it or to keep it alive while adding a new rule. If this counter * reaches zero, this struct must not be modified, but this counter can * still be read from within an RCU read-side critical section. When * adding a new rule to an object with a usage counter of zero, we must * wait until the pointer to this object is set to NULL (or recycled). */ refcount_t usage; /** * @lock: Protects against concurrent modifications. This lock must be * held from the time @usage drops to zero until any weak references * from @underobj to this object have been cleaned up. * * Lock ordering: inode->i_lock nests inside this. */ spinlock_t lock; /** * @underobj: Used when cleaning up an object and to mark an object as * tied to its underlying kernel structure. This pointer is protected * by @lock. Cf. landlock_release_inodes() and release_inode(). */ void *underobj; union { /** * @rcu_free: Enables lockless use of @usage, @lock and * @underobj from within an RCU read-side critical section. * @rcu_free and @underops are only used by * landlock_put_object(). */ struct rcu_head rcu_free; /** * @underops: Enables landlock_put_object() to release the * underlying object (e.g. inode). */ const struct landlock_object_underops *underops; };};
struct landlock_object *landlock_create_object(const struct landlock_object_underops *const underops, void *const underobj);
void landlock_put_object(struct landlock_object *const object);
static inline void landlock_get_object(struct landlock_object *const object){ if (object) refcount_inc(&object->usage);}
#endif /* _SECURITY_LANDLOCK_OBJECT_H */