text: // SPDX-License-Identifier: GPL-2.0-only
  /* Copyright (c) 2011-2014 PLUMgrid, http://plumgrid.com
   */
  #include <linux/bpf.h>
  #include <linux/bpf-cgroup.h>
  #include <linux/bpf_trace.h>
  #include <linux/bpf_lirc.h>
  #include <linux/bpf_verifier.h>
  #include <linux/btf.h>
  #include <linux/syscalls.h>
  #include <linux/slab.h>
  #include <linux/sched/signal.h>
  #include <linux/vmalloc.h>
  #include <linux/mmzone.h>
  #include <linux/anon_inodes.h>
  #include <linux/fdtable.h>
  #include <linux/file.h>
  #include <linux/fs.h>
  #include <linux/license.h>
  #include <linux/filter.h>
  #include <linux/kernel.h>
  #include <linux/idr.h>
  #include <linux/cred.h>
  #include <linux/timekeeping.h>
  #include <linux/ctype.h>
  #include <linux/nospec.h>
  #include <linux/audit.h>
  #include <uapi/linux/btf.h>
  #include <linux/pgtable.h>
  #include <linux/bpf_lsm.h>
  #include <linux/poll.h>
  #include <linux/bpf-netns.h>
  #include <linux/rcupdate_trace.h>
  #include <linux/memcontrol.h>
  #include <linux/trace_events.h>
  
  #define IS_FD_ARRAY(map) ((map)->map_type == BPF_MAP_TYPE_PERF_EVENT_ARRAY || \
  			  (map)->map_type == BPF_MAP_TYPE_CGROUP_ARRAY || \
  			  (map)->map_type == BPF_MAP_TYPE_ARRAY_OF_MAPS)
  #define IS_FD_PROG_ARRAY(map) ((map)->map_type == BPF_MAP_TYPE_PROG_ARRAY)
  #define IS_FD_HASH(map) ((map)->map_type == BPF_MAP_TYPE_HASH_OF_MAPS)
  #define IS_FD_MAP(map) (IS_FD_ARRAY(map) || IS_FD_PROG_ARRAY(map) || \
  			IS_FD_HASH(map))
  
  #define BPF_OBJ_FLAG_MASK   (BPF_F_RDONLY | BPF_F_WRONLY)
  
  DEFINE_PER_CPU(int, bpf_prog_active);
  static DEFINE_IDR(prog_idr);
  static DEFINE_SPINLOCK(prog_idr_lock);
  static DEFINE_IDR(map_idr);
  static DEFINE_SPINLOCK(map_idr_lock);
  static DEFINE_IDR(link_idr);
  static DEFINE_SPINLOCK(link_idr_lock);
  
  int sysctl_unprivileged_bpf_disabled __read_mostly =
  	IS_BUILTIN(CONFIG_BPF_UNPRIV_DEFAULT_OFF) ? 2 : 0;
  
  static const struct bpf_map_ops * const bpf_map_types[] = {
  #define BPF_PROG_TYPE(_id, _name, prog_ctx_type, kern_ctx_type)
  #define BPF_MAP_TYPE(_id, _ops) \
  	[_id] = &_ops,
  #define BPF_LINK_TYPE(_id, _name)
  #include <linux/bpf_types.h>
  #undef BPF_PROG_TYPE
  #undef BPF_MAP_TYPE
  #undef BPF_LINK_TYPE
  };
  
  /*
   * If we're handed a bigger struct than we know of, ensure all the unknown bits
   * are 0 - i.e. new user-space does not rely on any kernel feature extensions
   * we don't know about yet.
   *
   * There is a ToCToU between this function call and the following
   * copy_from_user() call. However, this is not a concern since this function is
   * meant to be a future-proofing of bits.
   */
  int bpf_check_uarg_tail_zero(bpfptr_t uaddr,
  			     size_t expected_size,
  			     size_t actual_size)
  {
  	int res;
  
  	if (unlikely(actual_size > PAGE_SIZE))	/* silly large */
  		return -E2BIG;
  
  	if (actual_size <= expected_size)
  		return 0;
  
  	if (uaddr.is_kernel)
  		res = memchr_inv(uaddr.kernel + expected_size, 0,
  				 actual_size - expected_size) == NULL;
  	else
  		res = check_zeroed_user(uaddr.user + expected_size,
  					actual_size - expected_size);
  	if (res < 0)
  		return res;
  	return res ? 0 : -E2BIG;
  }
  
  const struct bpf_map_ops bpf_map_offload_ops = {
  	.map_meta_equal = bpf_map_meta_equal,
  	.map_alloc = bpf_map_offload_map_alloc,
  	.map_free = bpf_map_offload_map_free,
  	.map_check_btf = map_check_no_btf,
  };
  
  static struct bpf_map *find_and_alloc_map(union bpf_attr *attr)
  {
  	const struct bpf_map_ops *ops;
  	u32 type = attr->map_type;
  	struct bpf_map *map;
  	int err;
  
  	if (type >= ARRAY_SIZE(bpf_map_types))
  		return ERR_PTR(-EINVAL);
  	type = array_index_nospec(type, ARRAY_SIZE(bpf_map_types));
  	ops = bpf_map_types[type];
  	if (!ops)
  		return ERR_PTR(-EINVAL);
  
  	if (ops->map_alloc_check) {
  		err = ops->map_alloc_check(attr);
  		if (err)
  			return ERR_PTR(err);
  	}
  	if (attr->map_ifindex)
  		ops = &bpf_map_offload_ops;
  	map = ops->map_alloc(attr);
  	if (IS_ERR(map))
  		return map;
  	map->ops = ops;
  	map->map_type = type;
  	return map;
  }
  
  static void bpf_map_write_active_inc(struct bpf_map *map)
  {
  	atomic64_inc(&map->writecnt);
  }
  
  static void bpf_map_write_active_dec(struct bpf_map *map)
  {
  	atomic64_dec(&map->writecnt);
  }
  
  bool bpf_map_write_active(const struct bpf_map *map)
  {
  	return atomic64_read(&map->writecnt) != 0;
  }
  
  static u32 bpf_map_value_size(const struct bpf_map *map)
  {
  	if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH ||
  	    map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH ||
  	    map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY ||
  	    map->map_type == BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE)
  		return round_up(map->value_size, 8) * num_possible_cpus();
  	else if (IS_FD_MAP(map))
  		return sizeof(u32);
  	else
  		return  map->value_size;
  }
  
  static void maybe_wait_bpf_programs(struct bpf_map *map)
  {
  	/* Wait for any running BPF programs to complete so that
  	 * userspace, when we return to it, knows that all programs
  	 * that could be running use the new map value.
  	 */
  	if (map->map_type == BPF_MAP_TYPE_HASH_OF_MAPS ||
  	    map->map_type == BPF_MAP_TYPE_ARRAY_OF_MAPS)
  		synchronize_rcu();
  }
  
  static int bpf_map_update_value(struct bpf_map *map, struct fd f, void *key,
  				void *value, __u64 flags)
  {
  	int err;
  
  	/* Need to create a kthread, thus must support schedule */
  	if (bpf_map_is_dev_bound(map)) {
  		return bpf_map_offload_update_elem(map, key, value, flags);
  	} else if (map->map_type == BPF_MAP_TYPE_CPUMAP ||
  		   map->map_type == BPF_MAP_TYPE_STRUCT_OPS) {
  		return map->ops->map_update_elem(map, key, value, flags);
  	} else if (map->map_type == BPF_MAP_TYPE_SOCKHASH ||
  		   map->map_type == BPF_MAP_TYPE_SOCKMAP) {
  		return sock_map_update_elem_sys(map, key, value, flags);
  	} else if (IS_FD_PROG_ARRAY(map)) {
  		return bpf_fd_array_map_update_elem(map, f.file, key, value,
  						    flags);
  	}
  
  	bpf_disable_instrumentation();
  	if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH ||
  	    map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH) {
  		err = bpf_percpu_hash_update(map, key, value, flags);
  	} else if (map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY) {
  		err = bpf_percpu_array_update(map, key, value, flags);
  	} else if (map->map_type == BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE) {
  		err = bpf_percpu_cgroup_storage_update(map, key, value,
  						       flags);
  	} else if (IS_FD_ARRAY(map)) {
  		rcu_read_lock();
  		err = bpf_fd_array_map_update_elem(map, f.file, key, value,
  						   flags);
  		rcu_read_unlock();
  	} else if (map->map_type == BPF_MAP_TYPE_HASH_OF_MAPS) {
  		rcu_read_lock();
  		err = bpf_fd_htab_map_update_elem(map, f.file, key, value,
  						  flags);
  		rcu_read_unlock();
  	} else if (map->map_type == BPF_MAP_TYPE_REUSEPORT_SOCKARRAY) {
  		/* rcu_read_lock() is not needed */
  		err = bpf_fd_reuseport_array_update_elem(map, key, value,
  							 flags);
  	} else if (map->map_type == BPF_MAP_TYPE_QUEUE ||
  		   map->map_type == BPF_MAP_TYPE_STACK ||
  		   map->map_type == BPF_MAP_TYPE_BLOOM_FILTER) {
  		err = map->ops->map_push_elem(map, value, flags);
  	} else {
  		rcu_read_lock();
  		err = map->ops->map_update_elem(map, key, value, flags);
  		rcu_read_unlock();
  	}
  	bpf_enable_instrumentation();
  	maybe_wait_bpf_programs(map);
  
  	return err;
  }
  
  static int bpf_map_copy_value(struct bpf_map *map, void *key, void *value,
  			      __u64 flags)
  {
  	void *ptr;
  	int err;
  
  	if (bpf_map_is_dev_bound(map))
  		return bpf_map_offload_lookup_elem(map, key, value);
  
  	bpf_disable_instrumentation();
  	if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH ||
  	    map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH) {
  		err = bpf_percpu_hash_copy(map, key, value);
  	} else if (map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY) {
  		err = bpf_percpu_array_copy(map, key, value);
  	} else if (map->map_type == BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE) {
  		err = bpf_percpu_cgroup_storage_copy(map, key, value);
  	} else if (map->map_type == BPF_MAP_TYPE_STACK_TRACE) {
  		err = bpf_stackmap_copy(map, key, value);
  	} else if (IS_FD_ARRAY(map) || IS_FD_PROG_ARRAY(map)) {
  		err = bpf_fd_array_map_lookup_elem(map, key, value);
  	} else if (IS_FD_HASH(map)) {
  		err = bpf_fd_htab_map_lookup_elem(map, key, value);
  	} else if (map->map_type == BPF_MAP_TYPE_REUSEPORT_SOCKARRAY) {
  		err = bpf_fd_reuseport_array_lookup_elem(map, key, value);
  	} else if (map->map_type == BPF_MAP_TYPE_QUEUE ||
  		   map->map_type == BPF_MAP_TYPE_STACK ||
  		   map->map_type == BPF_MAP_TYPE_BLOOM_FILTER) {
  		err = map->ops->map_peek_elem(map, value);
  	} else if (map->map_type == BPF_MAP_TYPE_STRUCT_OPS) {
  		/* struct_ops map requires directly updating "value" */
  		err = bpf_struct_ops_map_sys_lookup_elem(map, key, value);
  	} else {
  		rcu_read_lock();
  		if (map->ops->map_lookup_elem_sys_only)
  			ptr = map->ops->map_lookup_elem_sys_only(map, key);
  		else
  			ptr = map->ops->map_lookup_elem(map, key);
  		if (IS_ERR(ptr)) {
  			err = PTR_ERR(ptr);
  		} else if (!ptr) {
  			err = -ENOENT;
  		} else {
  			err = 0;
  			if (flags & BPF_F_LOCK)
  				/* lock 'ptr' and copy everything but lock */
  				copy_map_value_locked(map, value, ptr, true);
  			else
  				copy_map_value(map, value, ptr);
  			/* mask lock and timer, since value wasn't zero inited */
  			check_and_init_map_value(map, value);
  		}
  		rcu_read_unlock();
  	}
  
  	bpf_enable_instrumentation();
  	maybe_wait_bpf_programs(map);
  
  	return err;
  }
  
  /* Please, do not use this function outside from the map creation path
   * (e.g. in map update path) without taking care of setting the active
   * memory cgroup (see at bpf_map_kmalloc_node() for example).
   */
  static void *__bpf_map_area_alloc(u64 size, int numa_node, bool mmapable)
  {
  	/* We really just want to fail instead of triggering OOM killer
  	 * under memory pressure, therefore we set __GFP_NORETRY to kmalloc,
  	 * which is used for lower order allocation requests.
  	 *
  	 * It has been observed that higher order allocation requests done by
  	 * vmalloc with __GFP_NORETRY being set might fail due to not trying
  	 * to reclaim memory from the page cache, thus we set
  	 * __GFP_RETRY_MAYFAIL to avoid such situations.
  	 */
  
  	const gfp_t gfp = __GFP_NOWARN | __GFP_ZERO | __GFP_ACCOUNT;
  	unsigned int flags = 0;
  	unsigned long align = 1;
  	void *area;
  
  	if (size >= SIZE_MAX)
  		return NULL;
  
  	/* kmalloc()'ed memory can't be mmap()'ed */
  	if (mmapable) {
  		BUG_ON(!PAGE_ALIGNED(size));
  		align = SHMLBA;
  		flags = VM_USERMAP;
  	} else if (size <= (PAGE_SIZE << PAGE_ALLOC_COSTLY_ORDER)) {
  		area = kmalloc_node(size, gfp | GFP_USER | __GFP_NORETRY,
  				    numa_node);
  		if (area != NULL)
  			return area;
  	}
  
  	return __vmalloc_node_range(size, align, VMALLOC_START, VMALLOC_END,
  			gfp | GFP_KERNEL | __GFP_RETRY_MAYFAIL, PAGE_KERNEL,
  			flags, numa_node, __builtin_return_address(0));
  }
  
  void *bpf_map_area_alloc(u64 size, int numa_node)
  {
  	return __bpf_map_area_alloc(size, numa_node, false);
  }
  
  void *bpf_map_area_mmapable_alloc(u64 size, int numa_node)
  {
  	return __bpf_map_area_alloc(size, numa_node, true);
  }
  
  void bpf_map_area_free(void *area)
  {
  	kvfree(area);
  }
  
  static u32 bpf_map_flags_retain_permanent(u32 flags)
  {
  	/* Some map creation flags are not tied to the map object but
  	 * rather to the map fd instead, so they have no meaning upon
  	 * map object inspection since multiple file descriptors with
  	 * different (access) properties can exist here. Thus, given
  	 * this has zero meaning for the map itself, lets clear these
  	 * from here.
  	 */
  	return flags & ~(BPF_F_RDONLY | BPF_F_WRONLY);
  }
  
  void bpf_map_init_from_attr(struct bpf_map *map, union bpf_attr *attr)
  {
  	map->map_type = attr->map_type;
  	map->key_size = attr->key_size;
  	map->value_size = attr->value_size;
  	map->max_entries = attr->max_entries;
  	map->map_flags = bpf_map_flags_retain_permanent(attr->map_flags);
  	map->numa_node = bpf_map_attr_numa_node(attr);
  	map->map_extra = attr->map_extra;
  }
  
  static int bpf_map_alloc_id(struct bpf_map *map)
  {
  	int id;
  
  	idr_preload(GFP_KERNEL);
  	spin_lock_bh(&map_idr_lock);
  	id = idr_alloc_cyclic(&map_idr, map, 1, INT_MAX, GFP_ATOMIC);
  	if (id > 0)
  		map->id = id;
  	spin_unlock_bh(&map_idr_lock);
  	idr_preload_end();
  
  	if (WARN_ON_ONCE(!id))
  		return -ENOSPC;
  
  	return id > 0 ? 0 : id;
  }
  
  void bpf_map_free_id(struct bpf_map *map, bool do_idr_lock)
  {
  	unsigned long flags;
  
  	/* Offloaded maps are removed from the IDR store when their device
  	 * disappears - even if someone holds an fd to them they are unusable,
  	 * the memory is gone, all ops will fail; they are simply waiting for
  	 * refcnt to drop to be freed.
  	 */
  	if (!map->id)
  		return;
  
  	if (do_idr_lock)
  		spin_lock_irqsave(&map_idr_lock, flags);
  	else
  		__acquire(&map_idr_lock);
  
  	idr_remove(&map_idr, map->id);
  	map->id = 0;
  
  	if (do_idr_lock)
  		spin_unlock_irqrestore(&map_idr_lock, flags);
  	else
  		__release(&map_idr_lock);
  }
  
  #ifdef CONFIG_MEMCG_KMEM
  static void bpf_map_save_memcg(struct bpf_map *map)
  {
  	map->memcg = get_mem_cgroup_from_mm(current->mm);
  }
  
  static void bpf_map_release_memcg(struct bpf_map *map)
  {
  	mem_cgroup_put(map->memcg);
  }
  
  void *bpf_map_kmalloc_node(const struct bpf_map *map, size_t size, gfp_t flags,
  			   int node)
  {
  	struct mem_cgroup *old_memcg;
  	void *ptr;
  
  	old_memcg = set_active_memcg(map->memcg);
  	ptr = kmalloc_node(size, flags | __GFP_ACCOUNT, node);
  	set_active_memcg(old_memcg);
  
  	return ptr;
  }
  
  void *bpf_map_kzalloc(const struct bpf_map *map, size_t size, gfp_t flags)
  {
  	struct mem_cgroup *old_memcg;
  	void *ptr;
  
  	old_memcg = set_active_memcg(map->memcg);
  	ptr = kzalloc(size, flags | __GFP_ACCOUNT);
  	set_active_memcg(old_memcg);
  
  	return ptr;
  }
  
  void __percpu *bpf_map_alloc_percpu(const struct bpf_map *map, size_t size,
  				    size_t align, gfp_t flags)
  {
  	struct mem_cgroup *old_memcg;
  	void __percpu *ptr;
  
  	old_memcg = set_active_memcg(map->memcg);
  	ptr = __alloc_percpu_gfp(size, align, flags | __GFP_ACCOUNT);
  	set_active_memcg(old_memcg);
  
  	return ptr;
  }
  
  #else
  static void bpf_map_save_memcg(struct bpf_map *map)
  {
  }
  
  static void bpf_map_release_memcg(struct bpf_map *map)
  {
  }
  #endif
  
  /* called from workqueue */
  static void bpf_map_free_deferred(struct work_struct *work)
  {
  	struct bpf_map *map = container_of(work, struct bpf_map, work);
  
  	security_bpf_map_free(map);
  	bpf_map_release_memcg(map);
  	/* implementation dependent freeing */
  	map->ops->map_free(map);
  }
  
  static void bpf_map_put_uref(struct bpf_map *map)
  {
  	if (atomic64_dec_and_test(&map->usercnt)) {
  		if (map->ops->map_release_uref)
  			map->ops->map_release_uref(map);
  	}
  }
  
  /* decrement map refcnt and schedule it for freeing via workqueue
   * (unrelying map implementation ops->map_free() might sleep)
   */
  static void __bpf_map_put(struct bpf_map *map, bool do_idr_lock)
  {
  	if (atomic64_dec_and_test(&map->refcnt)) {
  		/* bpf_map_free_id() must be called first */
  		bpf_map_free_id(map, do_idr_lock);
  		btf_put(map->btf);
  		INIT_WORK(&map->work, bpf_map_free_deferred);
  		schedule_work(&map->work);
  	}
  }
  
  void bpf_map_put(struct bpf_map *map)
  {
  	__bpf_map_put(map, true);
  }
  EXPORT_SYMBOL_GPL(bpf_map_put);
  
  void bpf_map_put_with_uref(struct bpf_map *map)
  {
  	bpf_map_put_uref(map);
  	bpf_map_put(map);
  }
  
  static int bpf_map_release(struct inode *inode, struct file *filp)
  {
  	struct bpf_map *map = filp->private_data;
  
  	if (map->ops->map_release)
  		map->ops->map_release(map, filp);
  
  	bpf_map_put_with_uref(map);
  	return 0;
  }
  
  static fmode_t map_get_sys_perms(struct bpf_map *map, struct fd f)
  {
  	fmode_t mode = f.file->f_mode;
  
  	/* Our file permissions may have been overridden by global
  	 * map permissions facing syscall side.
  	 */
  	if (READ_ONCE(map->frozen))
  		mode &= ~FMODE_CAN_WRITE;
  	return mode;
  }
  
  #ifdef CONFIG_PROC_FS
  /* Provides an approximation of the map's memory footprint.
   * Used only to provide a backward compatibility and display
   * a reasonable "memlock" info.
   */
  static unsigned long bpf_map_memory_footprint(const struct bpf_map *map)
  {
  	unsigned long size;
  
  	size = round_up(map->key_size + bpf_map_value_size(map), 8);
  
  	return round_up(map->max_entries * size, PAGE_SIZE);
  }
  
  static void bpf_map_show_fdinfo(struct seq_file *m, struct file *filp)
  {
  	struct bpf_map *map = filp->private_data;
  	u32 type = 0, jited = 0;
  
  	if (map_type_contains_progs(map)) {
  		spin_lock(&map->owner.lock);
  		type  = map->owner.type;
  		jited = map->owner.jited;
  		spin_unlock(&map->owner.lock);
  	}
  
  	seq_printf(m,
  		   "map_type:\t%u\n"
  		   "key_size:\t%u\n"
  		   "value_size:\t%u\n"
  		   "max_entries:\t%u\n"
  		   "map_flags:\t%#x\n"
  		   "map_extra:\t%#llx\n"
  		   "memlock:\t%lu\n"
  		   "map_id:\t%u\n"
  		   "frozen:\t%u\n",
  		   map->map_type,
  		   map->key_size,
  		   map->value_size,
  		   map->max_entries,
  		   map->map_flags,
  		   (unsigned long long)map->map_extra,
  		   bpf_map_memory_footprint(map),
  		   map->id,
  		   READ_ONCE(map->frozen));
  	if (type) {
  		seq_printf(m, "owner_prog_type:\t%u\n", type);
  		seq_printf(m, "owner_jited:\t%u\n", jited);
  	}
  }
  #endif
  
  static ssize_t bpf_dummy_read(struct file *filp, char __user *buf, size_t siz,
  			      loff_t *ppos)
  {
  	/* We need this handler such that alloc_file() enables
  	 * f_mode with FMODE_CAN_READ.
  	 */
  	return -EINVAL;
  }
  
  static ssize_t bpf_dummy_write(struct file *filp, const char __user *buf,
  			       size_t siz, loff_t *ppos)
  {
  	/* We need this handler such that alloc_file() enables
  	 * f_mode with FMODE_CAN_WRITE.
  	 */
  	return -EINVAL;
  }
  
  /* called for any extra memory-mapped regions (except initial) */
  static void bpf_map_mmap_open(struct vm_area_struct *vma)
  {
  	struct bpf_map *map = vma->vm_file->private_data;
  
  	if (vma->vm_flags & VM_MAYWRITE)
  		bpf_map_write_active_inc(map);
  }
  
  /* called for all unmapped memory region (including initial) */
  static void bpf_map_mmap_close(struct vm_area_struct *vma)
  {
  	struct bpf_map *map = vma->vm_file->private_data;
  
  	if (vma->vm_flags & VM_MAYWRITE)
  		bpf_map_write_active_dec(map);
  }
  
  static const struct vm_operations_struct bpf_map_default_vmops = {
  	.open		= bpf_map_mmap_open,
  	.close		= bpf_map_mmap_close,
  };
  
  static int bpf_map_mmap(struct file *filp, struct vm_area_struct *vma)
  {
  	struct bpf_map *map = filp->private_data;
  	int err;
  
  	if (!map->ops->map_mmap || map_value_has_spin_lock(map) ||
  	    map_value_has_timer(map))
  		return -ENOTSUPP;
  
  	if (!(vma->vm_flags & VM_SHARED))
  		return -EINVAL;
  
  	mutex_lock(&map->freeze_mutex);
  
  	if (vma->vm_flags & VM_WRITE) {
  		if (map->frozen) {
  			err = -EPERM;
  			goto out;
  		}
  		/* map is meant to be read-only, so do not allow mapping as
  		 * writable, because it's possible to leak a writable page
  		 * reference and allows user-space to still modify it after
  		 * freezing, while verifier will assume contents do not change
  		 */
  		if (map->map_flags & BPF_F_RDONLY_PROG) {
  			err = -EACCES;
  			goto out;
  		}
  	}
  
  	/* set default open/close callbacks */
  	vma->vm_ops = &bpf_map_default_vmops;
  	vma->vm_private_data = map;
  	vma->vm_flags &= ~VM_MAYEXEC;
  	if (!(vma->vm_flags & VM_WRITE))
  		/* disallow re-mapping with PROT_WRITE */
  		vma->vm_flags &= ~VM_MAYWRITE;
  
  	err = map->ops->map_mmap(map, vma);
  	if (err)
  		goto out;
  
  	if (vma->vm_flags & VM_MAYWRITE)
  		bpf_map_write_active_inc(map);
  out:
  	mutex_unlock(&map->freeze_mutex);
  	return err;
  }
  
  static __poll_t bpf_map_poll(struct file *filp, struct poll_table_struct *pts)
  {
  	struct bpf_map *map = filp->private_data;
  
  	if (map->ops->map_poll)
  		return map->ops->map_poll(map, filp, pts);
  
  	return EPOLLERR;
  }
  
  const struct file_operations bpf_map_fops = {
  #ifdef CONFIG_PROC_FS
  	.show_fdinfo	= bpf_map_show_fdinfo,
  #endif
  	.release	= bpf_map_release,
  	.read		= bpf_dummy_read,
  	.write		= bpf_dummy_write,
  	.mmap		= bpf_map_mmap,
  	.poll		= bpf_map_poll,
  };
  
  int bpf_map_new_fd(struct bpf_map *map, int flags)
  {
  	int ret;
  
  	ret = security_bpf_map(map, OPEN_FMODE(flags));
  	if (ret < 0)
  		return ret;
  
  	return anon_inode_getfd("bpf-map", &bpf_map_fops, map,
  				flags | O_CLOEXEC);
  }
  
  int bpf_get_file_flag(int flags)
  {
  	if ((flags & BPF_F_RDONLY) && (flags & BPF_F_WRONLY))
  		return -EINVAL;
  	if (flags & BPF_F_RDONLY)
  		return O_RDONLY;
  	if (flags & BPF_F_WRONLY)
  		return O_WRONLY;
  	return O_RDWR;
  }
  
  /* helper macro to check that unused fields 'union bpf_attr' are zero */
  #define CHECK_ATTR(CMD) \
  	memchr_inv((void *) &attr->CMD##_LAST_FIELD + \
  		   sizeof(attr->CMD##_LAST_FIELD), 0, \
  		   sizeof(*attr) - \
  		   offsetof(union bpf_attr, CMD##_LAST_FIELD) - \
  		   sizeof(attr->CMD##_LAST_FIELD)) != NULL
  
  /* dst and src must have at least "size" number of bytes.
   * Return strlen on success and < 0 on error.
   */
  int bpf_obj_name_cpy(char *dst, const char *src, unsigned int size)
  {
  	const char *end = src + size;
  	const char *orig_src = src;
  
  	memset(dst, 0, size);
  	/* Copy all isalnum(), '_' and '.' chars. */
  	while (src < end && *src) {
  		if (!isalnum(*src) &&
  		    *src != '_' && *src != '.')
  			return -EINVAL;
  		*dst++ = *src++;
  	}
  
  	/* No '\0' found in "size" number of bytes */
  	if (src == end)
  		return -EINVAL;
  
  	return src - orig_src;
  }
  
  int map_check_no_btf(const struct bpf_map *map,
  		     const struct btf *btf,
  		     const struct btf_type *key_type,
  		     const struct btf_type *value_type)
  {
  	return -ENOTSUPP;
  }
  
  static int map_check_btf(struct bpf_map *map, const struct btf *btf,
  			 u32 btf_key_id, u32 btf_value_id)
  {
  	const struct btf_type *key_type, *value_type;
  	u32 key_size, value_size;
  	int ret = 0;
  
  	/* Some maps allow key to be unspecified. */
  	if (btf_key_id) {
  		key_type = btf_type_id_size(btf, &btf_key_id, &key_size);
  		if (!key_type || key_size != map->key_size)
  			return -EINVAL;
  	} else {
  		key_type = btf_type_by_id(btf, 0);
  		if (!map->ops->map_check_btf)
  			return -EINVAL;
  	}
  
  	value_type = btf_type_id_size(btf, &btf_value_id, &value_size);
  	if (!value_type || value_size != map->value_size)
  		return -EINVAL;
  
  	map->spin_lock_off = btf_find_spin_lock(btf, value_type);
  
  	if (map_value_has_spin_lock(map)) {
  		if (map->map_flags & BPF_F_RDONLY_PROG)
  			return -EACCES;
  		if (map->map_type != BPF_MAP_TYPE_HASH &&
  		    map->map_type != BPF_MAP_TYPE_ARRAY &&
  		    map->map_type != BPF_MAP_TYPE_CGROUP_STORAGE &&
  		    map->map_type != BPF_MAP_TYPE_SK_STORAGE &&
  		    map->map_type != BPF_MAP_TYPE_INODE_STORAGE &&
  		    map->map_type != BPF_MAP_TYPE_TASK_STORAGE)
  			return -ENOTSUPP;
  		if (map->spin_lock_off + sizeof(struct bpf_spin_lock) >
  		    map->value_size) {
  			WARN_ONCE(1,
  				  "verifier bug spin_lock_off %d value_size %d\n",
  				  map->spin_lock_off, map->value_size);
  			return -EFAULT;
  		}
  	}
  
  	map->timer_off = btf_find_timer(btf, value_type);
  	if (map_value_has_timer(map)) {
  		if (map->map_flags & BPF_F_RDONLY_PROG)
  			return -EACCES;
  		if (map->map_type != BPF_MAP_TYPE_HASH &&
  		    map->map_type != BPF_MAP_TYPE_LRU_HASH &&
  		    map->map_type != BPF_MAP_TYPE_ARRAY)
  			return -EOPNOTSUPP;
  	}
  
  	if (map->ops->map_check_btf)
  		ret = map->ops->map_check_btf(map, btf, key_type, value_type);
  
  	return ret;
  }
  
  #define BPF_MAP_CREATE_LAST_FIELD map_extra
  /* called via syscall */
  static int map_create(union bpf_attr *attr)
  {
  	int numa_node = bpf_map_attr_numa_node(attr);
  	struct bpf_map *map;
  	int f_flags;
  	int err;
  
  	err = CHECK_ATTR(BPF_MAP_CREATE);
  	if (err)
  		return -EINVAL;
  
  	if (attr->btf_vmlinux_value_type_id) {
  		if (attr->map_type != BPF_MAP_TYPE_STRUCT_OPS ||
  		    attr->btf_key_type_id || attr->btf_value_type_id)
  			return -EINVAL;
  	} else if (attr->btf_key_type_id && !attr->btf_value_type_id) {
  		return -EINVAL;
  	}
  
  	if (attr->map_type != BPF_MAP_TYPE_BLOOM_FILTER &&
  	    attr->map_extra != 0)
  		return -EINVAL;
  
  	f_flags = bpf_get_file_flag(attr->map_flags);
  	if (f_flags < 0)
  		return f_flags;
  
  	if (numa_node != NUMA_NO_NODE &&
  	    ((unsigned int)numa_node >= nr_node_ids ||
  	     !node_online(numa_node)))
  		return -EINVAL;
  
  	/* find map type and init map: hashtable vs rbtree vs bloom vs ... */
  	map = find_and_alloc_map(attr);
  	if (IS_ERR(map))
  		return PTR_ERR(map);
  
  	err = bpf_obj_name_cpy(map->name, attr->map_name,
  			       sizeof(attr->map_name));
  	if (err < 0)
  		goto free_map;
  
  	atomic64_set(&map->refcnt, 1);
  	atomic64_set(&map->usercnt, 1);
  	mutex_init(&map->freeze_mutex);
  	spin_lock_init(&map->owner.lock);
  
  	map->spin_lock_off = -EINVAL;
  	map->timer_off = -EINVAL;
  	if (attr->btf_key_type_id || attr->btf_value_type_id ||
  	    /* Even the map's value is a kernel's struct,
  	     * the bpf_prog.o must have BTF to begin with
  	     * to figure out the corresponding kernel's
  	     * counter part.  Thus, attr->btf_fd has
  	     * to be valid also.
  	     */
  	    attr->btf_vmlinux_value_type_id) {
  		struct btf *btf;
  
  		btf = btf_get_by_fd(attr->btf_fd);
  		if (IS_ERR(btf)) {
  			err = PTR_ERR(btf);
  			goto free_map;
  		}
  		if (btf_is_kernel(btf)) {
  			btf_put(btf);
  			err = -EACCES;
  			goto free_map;
  		}
  		map->btf = btf;
  
  		if (attr->btf_value_type_id) {
  			err = map_check_btf(map, btf, attr->btf_key_type_id,
  					    attr->btf_value_type_id);
  			if (err)
  				goto free_map;
  		}
  
  		map->btf_key_type_id = attr->btf_key_type_id;
  		map->btf_value_type_id = attr->btf_value_type_id;
  		map->btf_vmlinux_value_type_id =
  			attr->btf_vmlinux_value_type_id;
  	}
  
  	err = security_bpf_map_alloc(map);
  	if (err)
  		goto free_map;
  
  	err = bpf_map_alloc_id(map);
  	if (err)
  		goto free_map_sec;
  
  	bpf_map_save_memcg(map);
  
  	err = bpf_map_new_fd(map, f_flags);
  	if (err < 0) {
  		/* failed to allocate fd.
  		 * bpf_map_put_with_uref() is needed because the above
  		 * bpf_map_alloc_id() has published the map
  		 * to the userspace and the userspace may
  		 * have refcnt-ed it through BPF_MAP_GET_FD_BY_ID.
  		 */
  		bpf_map_put_with_uref(map);
  		return err;
  	}
  
  	return err;
  
  free_map_sec:
  	security_bpf_map_free(map);
  free_map:
  	btf_put(map->btf);
  	map->ops->map_free(map);
  	return err;
  }
  
  /* if error is returned, fd is released.
   * On success caller should complete fd access with matching fdput()
   */
  struct bpf_map *__bpf_map_get(struct fd f)
  {
  	if (!f.file)
  		return ERR_PTR(-EBADF);
  	if (f.file->f_op != &bpf_map_fops) {
  		fdput(f);
  		return ERR_PTR(-EINVAL);
  	}
  
  	return f.file->private_data;
  }
  
  void bpf_map_inc(struct bpf_map *map)
  {
  	atomic64_inc(&map->refcnt);
  }
  EXPORT_SYMBOL_GPL(bpf_map_inc);
  
  void bpf_map_inc_with_uref(struct bpf_map *map)
  {
  	atomic64_inc(&map->refcnt);
  	atomic64_inc(&map->usercnt);
  }
  EXPORT_SYMBOL_GPL(bpf_map_inc_with_uref);
  
  struct bpf_map *bpf_map_get(u32 ufd)
  {
  	struct fd f = fdget(ufd);
  	struct bpf_map *map;
  
  	map = __bpf_map_get(f);
  	if (IS_ERR(map))
  		return map;
  
  	bpf_map_inc(map);
  	fdput(f);
  
  	return map;
  }
  EXPORT_SYMBOL(bpf_map_get);
  
  struct bpf_map *bpf_map_get_with_uref(u32 ufd)
  {
  	struct fd f = fdget(ufd);
  	struct bpf_map *map;
  
  	map = __bpf_map_get(f);
  	if (IS_ERR(map))
  		return map;
  
  	bpf_map_inc_with_uref(map);
  	fdput(f);
  
  	return map;
  }
  
  /* map_idr_lock should have been held */
  static struct bpf_map *__bpf_map_inc_not_zero(struct bpf_map *map, bool uref)
  {
  	int refold;
  
  	refold = atomic64_fetch_add_unless(&map->refcnt, 1, 0);
  	if (!refold)
  		return ERR_PTR(-ENOENT);
  	if (uref)
  		atomic64_inc(&map->usercnt);
  
  	return map;
  }
  
  struct bpf_map *bpf_map_inc_not_zero(struct bpf_map *map)
  {
  	spin_lock_bh(&map_idr_lock);
  	map = __bpf_map_inc_not_zero(map, false);
  	spin_unlock_bh(&map_idr_lock);
  
  	return map;
  }
  EXPORT_SYMBOL_GPL(bpf_map_inc_not_zero);
  
  int __weak bpf_stackmap_copy(struct bpf_map *map, void *key, void *value)
  {
  	return -ENOTSUPP;
  }
  
  static void *__bpf_copy_key(void __user *ukey, u64 key_size)
  {
  	if (key_size)
  		return vmemdup_user(ukey, key_size);
  
  	if (ukey)
  		return ERR_PTR(-EINVAL);
  
  	return NULL;
  }
  
  static void *___bpf_copy_key(bpfptr_t ukey, u64 key_size)
  {
  	if (key_size)
  		return kvmemdup_bpfptr(ukey, key_size);
  
  	if (!bpfptr_is_null(ukey))
  		return ERR_PTR(-EINVAL);
  
  	return NULL;
  }
  
  /* last field in 'union bpf_attr' used by this command */
  #define BPF_MAP_LOOKUP_ELEM_LAST_FIELD flags
  
  static int map_lookup_elem(union bpf_attr *attr)
  {
  	void __user *ukey = u64_to_user_ptr(attr->key);
  	void __user *uvalue = u64_to_user_ptr(attr->value);
  	int ufd = attr->map_fd;
  	struct bpf_map *map;
  	void *key, *value;
  	u32 value_size;
  	struct fd f;
  	int err;
  
  	if (CHECK_ATTR(BPF_MAP_LOOKUP_ELEM))
  		return -EINVAL;
  
  	if (attr->flags & ~BPF_F_LOCK)
  		return -EINVAL;
  
  	f = fdget(ufd);
  	map = __bpf_map_get(f);
  	if (IS_ERR(map))
  		return PTR_ERR(map);
  	if (!(map_get_sys_perms(map, f) & FMODE_CAN_READ)) {
  		err = -EPERM;
  		goto err_put;
  	}
  
  	if ((attr->flags & BPF_F_LOCK) &&
  	    !map_value_has_spin_lock(map)) {
  		err = -EINVAL;
  		goto err_put;
  	}
  
  	key = __bpf_copy_key(ukey, map->key_size);
  	if (IS_ERR(key)) {
  		err = PTR_ERR(key);
  		goto err_put;
  	}
  
  	value_size = bpf_map_value_size(map);
  
  	err = -ENOMEM;
  	value = kvmalloc(value_size, GFP_USER | __GFP_NOWARN);
  	if (!value)
  		goto free_key;
  
  	if (map->map_type == BPF_MAP_TYPE_BLOOM_FILTER) {
  		if (copy_from_user(value, uvalue, value_size))
  			err = -EFAULT;
  		else
  			err = bpf_map_copy_value(map, key, value, attr->flags);
  		goto free_value;
  	}
  
  	err = bpf_map_copy_value(map, key, value, attr->flags);
  	if (err)
  		goto free_value;
  
  	err = -EFAULT;
  	if (copy_to_user(uvalue, value, value_size) != 0)
  		goto free_value;
  
  	err = 0;
  
  free_value:
  	kvfree(value);
  free_key:
  	kvfree(key);
  err_put:
  	fdput(f);
  	return err;
  }
  
  
  #define BPF_MAP_UPDATE_ELEM_LAST_FIELD flags
  
  static int map_update_elem(union bpf_attr *attr, bpfptr_t uattr)
  {
  	bpfptr_t ukey = make_bpfptr(attr->key, uattr.is_kernel);
  	bpfptr_t uvalue = make_bpfptr(attr->value, uattr.is_kernel);
  	int ufd = attr->map_fd;
  	struct bpf_map *map;
  	void *key, *value;
  	u32 value_size;
  	struct fd f;
  	int err;
  
  	if (CHECK_ATTR(BPF_MAP_UPDATE_ELEM))
  		return -EINVAL;
  
  	f = fdget(ufd);
  	map = __bpf_map_get(f);
  	if (IS_ERR(map))
  		return PTR_ERR(map);
  	bpf_map_write_active_inc(map);
  	if (!(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) {
  		err = -EPERM;
  		goto err_put;
  	}
  
  	if ((attr->flags & BPF_F_LOCK) &&
  	    !map_value_has_spin_lock(map)) {
  		err = -EINVAL;
  		goto err_put;
  	}
  
  	key = ___bpf_copy_key(ukey, map->key_size);
  	if (IS_ERR(key)) {
  		err = PTR_ERR(key);
  		goto err_put;
  	}
  
  	value_size = bpf_map_value_size(map);
  
  	err = -ENOMEM;
  	value = kvmalloc(value_size, GFP_USER | __GFP_NOWARN);
  	if (!value)
  		goto free_key;
  
  	err = -EFAULT;
  	if (copy_from_bpfptr(value, uvalue, value_size) != 0)
  		goto free_value;
  
  	err = bpf_map_update_value(map, f, key, value, attr->flags);
  
  free_value:
  	kvfree(value);
  free_key:
  	kvfree(key);
  err_put:
  	bpf_map_write_active_dec(map);
  	fdput(f);
  	return err;
  }
  
  #define BPF_MAP_DELETE_ELEM_LAST_FIELD key
  
  static int map_delete_elem(union bpf_attr *attr)
  {
  	void __user *ukey = u64_to_user_ptr(attr->key);
  	int ufd = attr->map_fd;
  	struct bpf_map *map;
  	struct fd f;
  	void *key;
  	int err;
  
  	if (CHECK_ATTR(BPF_MAP_DELETE_ELEM))
  		return -EINVAL;
  
  	f = fdget(ufd);
  	map = __bpf_map_get(f);
  	if (IS_ERR(map))
  		return PTR_ERR(map);
  	bpf_map_write_active_inc(map);
  	if (!(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) {
  		err = -EPERM;
  		goto err_put;
  	}
  
  	key = __bpf_copy_key(ukey, map->key_size);
  	if (IS_ERR(key)) {
  		err = PTR_ERR(key);
  		goto err_put;
  	}
  
  	if (bpf_map_is_dev_bound(map)) {
  		err = bpf_map_offload_delete_elem(map, key);
  		goto out;
  	} else if (IS_FD_PROG_ARRAY(map) ||
  		   map->map_type == BPF_MAP_TYPE_STRUCT_OPS) {
  		/* These maps require sleepable context */
  		err = map->ops->map_delete_elem(map, key);
  		goto out;
  	}
  
  	bpf_disable_instrumentation();
  	rcu_read_lock();
  	err = map->ops->map_delete_elem(map, key);
  	rcu_read_unlock();
  	bpf_enable_instrumentation();
  	maybe_wait_bpf_programs(map);
  out:
  	kvfree(key);
  err_put:
  	bpf_map_write_active_dec(map);
  	fdput(f);
  	return err;
  }
  
  /* last field in 'union bpf_attr' used by this command */
  #define BPF_MAP_GET_NEXT_KEY_LAST_FIELD next_key
  
  static int map_get_next_key(union bpf_attr *attr)
  {
  	void __user *ukey = u64_to_user_ptr(attr->key);
  	void __user *unext_key = u64_to_user_ptr(attr->next_key);
  	int ufd = attr->map_fd;
  	struct bpf_map *map;
  	void *key, *next_key;
  	struct fd f;
  	int err;
  
  	if (CHECK_ATTR(BPF_MAP_GET_NEXT_KEY))
  		return -EINVAL;
  
  	f = fdget(ufd);
  	map = __bpf_map_get(f);
  	if (IS_ERR(map))
  		return PTR_ERR(map);
  	if (!(map_get_sys_perms(map, f) & FMODE_CAN_READ)) {
  		err = -EPERM;
  		goto err_put;
  	}
  
  	if (ukey) {
  		key = __bpf_copy_key(ukey, map->key_size);
  		if (IS_ERR(key)) {
  			err = PTR_ERR(key);
  			goto err_put;
  		}
  	} else {
  		key = NULL;
  	}
  
  	err = -ENOMEM;
  	next_key = kvmalloc(map->key_size, GFP_USER);
  	if (!next_key)
  		goto free_key;
  
  	if (bpf_map_is_dev_bound(map)) {
  		err = bpf_map_offload_get_next_key(map, key, next_key);
  		goto out;
  	}
  
  	rcu_read_lock();
  	err = map->ops->map_get_next_key(map, key, next_key);
  	rcu_read_unlock();
  out:
  	if (err)
  		goto free_next_key;
  
  	err = -EFAULT;
  	if (copy_to_user(unext_key, next_key, map->key_size) != 0)
  		goto free_next_key;
  
  	err = 0;
  
  free_next_key:
  	kvfree(next_key);
  free_key:
  	kvfree(key);
  err_put:
  	fdput(f);
  	return err;
  }
  
  int generic_map_delete_batch(struct bpf_map *map,
  			     const union bpf_attr *attr,
  			     union bpf_attr __user *uattr)
  {
  	void __user *keys = u64_to_user_ptr(attr->batch.keys);
  	u32 cp, max_count;
  	int err = 0;
  	void *key;
  
  	if (attr->batch.elem_flags & ~BPF_F_LOCK)
  		return -EINVAL;
  
  	if ((attr->batch.elem_flags & BPF_F_LOCK) &&
  	    !map_value_has_spin_lock(map)) {
  		return -EINVAL;
  	}
  
  	max_count = attr->batch.count;
  	if (!max_count)
  		return 0;
  
  	key = kvmalloc(map->key_size, GFP_USER | __GFP_NOWARN);
  	if (!key)
  		return -ENOMEM;
  
  	for (cp = 0; cp < max_count; cp++) {
  		err = -EFAULT;
  		if (copy_from_user(key, keys + cp * map->key_size,
  				   map->key_size))
  			break;
  
  		if (bpf_map_is_dev_bound(map)) {
  			err = bpf_map_offload_delete_elem(map, key);
  			break;
  		}
  
  		bpf_disable_instrumentation();
  		rcu_read_lock();
  		err = map->ops->map_delete_elem(map, key);
  		rcu_read_unlock();
  		bpf_enable_instrumentation();
  		if (err)
  			break;
  		cond_resched();
  	}
  	if (copy_to_user(&uattr->batch.count, &cp, sizeof(cp)))
  		err = -EFAULT;
  
  	kvfree(key);
  
  	maybe_wait_bpf_programs(map);
  	return err;
  }
  
  int generic_map_update_batch(struct bpf_map *map,
  			     const union bpf_attr *attr,
  			     union bpf_attr __user *uattr)
  {
  	void __user *values = u64_to_user_ptr(attr->batch.values);
  	void __user *keys = u64_to_user_ptr(attr->batch.keys);
  	u32 value_size, cp, max_count;
  	int ufd = attr->batch.map_fd;
  	void *key, *value;
  	struct fd f;
  	int err = 0;
  
  	if (attr->batch.elem_flags & ~BPF_F_LOCK)
  		return -EINVAL;
  
  	if ((attr->batch.elem_flags & BPF_F_LOCK) &&
  	    !map_value_has_spin_lock(map)) {
  		return -EINVAL;
  	}
  
  	value_size = bpf_map_value_size(map);
  
  	max_count = attr->batch.count;
  	if (!max_count)
  		return 0;
  
  	key = kvmalloc(map->key_size, GFP_USER | __GFP_NOWARN);
  	if (!key)
  		return -ENOMEM;
  
  	value = kvmalloc(value_size, GFP_USER | __GFP_NOWARN);
  	if (!value) {
  		kvfree(key);
  		return -ENOMEM;
  	}
  
  	f = fdget(ufd); /* bpf_map_do_batch() guarantees ufd is valid */
  	for (cp = 0; cp < max_count; cp++) {
  		err = -EFAULT;
  		if (copy_from_user(key, keys + cp * map->key_size,
  		    map->key_size) ||
  		    copy_from_user(value, values + cp * value_size, value_size))
  			break;
  
  		err = bpf_map_update_value(map, f, key, value,
  					   attr->batch.elem_flags);
  
  		if (err)
  			break;
  		cond_resched();
  	}
  
  	if (copy_to_user(&uattr->batch.count, &cp, sizeof(cp)))
  		err = -EFAULT;
  
  	kvfree(value);
  	kvfree(key);
  	fdput(f);
  	return err;
  }
  
  #define MAP_LOOKUP_RETRIES 3
  
  int generic_map_lookup_batch(struct bpf_map *map,
  				    const union bpf_attr *attr,
  				    union bpf_attr __user *uattr)
  {
  	void __user *uobatch = u64_to_user_ptr(attr->batch.out_batch);
  	void __user *ubatch = u64_to_user_ptr(attr->batch.in_batch);
  	void __user *values = u64_to_user_ptr(attr->batch.values);
  	void __user *keys = u64_to_user_ptr(attr->batch.keys);
  	void *buf, *buf_prevkey, *prev_key, *key, *value;
  	int err, retry = MAP_LOOKUP_RETRIES;
  	u32 value_size, cp, max_count;
  
  	if (attr->batch.elem_flags & ~BPF_F_LOCK)
  		return -EINVAL;
  
  	if ((attr->batch.elem_flags & BPF_F_LOCK) &&
  	    !map_value_has_spin_lock(map))
  		return -EINVAL;
  
  	value_size = bpf_map_value_size(map);
  
  	max_count = attr->batch.count;
  	if (!max_count)
  		return 0;
  
  	if (put_user(0, &uattr->batch.count))
  		return -EFAULT;
  
  	buf_prevkey = kvmalloc(map->key_size, GFP_USER | __GFP_NOWARN);
  	if (!buf_prevkey)
  		return -ENOMEM;
  
  	buf = kvmalloc(map->key_size + value_size, GFP_USER | __GFP_NOWARN);
  	if (!buf) {
  		kvfree(buf_prevkey);
  		return -ENOMEM;
  	}
  
  	err = -EFAULT;
  	prev_key = NULL;
  	if (ubatch && copy_from_user(buf_prevkey, ubatch, map->key_size))
  		goto free_buf;
  	key = buf;
  	value = key + map->key_size;
  	if (ubatch)
  		prev_key = buf_prevkey;
  
  	for (cp = 0; cp < max_count;) {
  		rcu_read_lock();
  		err = map->ops->map_get_next_key(map, prev_key, key);
  		rcu_read_unlock();
  		if (err)
  			break;
  		err = bpf_map_copy_value(map, key, value,
  					 attr->batch.elem_flags);
  
  		if (err == -ENOENT) {
  			if (retry) {
  				retry--;
  				continue;
  			}
  			err = -EINTR;
  			break;
  		}
  
  		if (err)
  			goto free_buf;
  
  		if (copy_to_user(keys + cp * map->key_size, key,
  				 map->key_size)) {
  			err = -EFAULT;
  			goto free_buf;
  		}
  		if (copy_to_user(values + cp * value_size, value, value_size)) {
  			err = -EFAULT;
  			goto free_buf;
  		}
  
  		if (!prev_key)
  			prev_key = buf_prevkey;
  
  		swap(prev_key, key);
  		retry = MAP_LOOKUP_RETRIES;
  		cp++;
  		cond_resched();
  	}
  
  	if (err == -EFAULT)
  		goto free_buf;
  
  	if ((copy_to_user(&uattr->batch.count, &cp, sizeof(cp)) ||
  		    (cp && copy_to_user(uobatch, prev_key, map->key_size))))
  		err = -EFAULT;
  
  free_buf:
  	kvfree(buf_prevkey);
  	kvfree(buf);
  	return err;
  }
  
  #define BPF_MAP_LOOKUP_AND_DELETE_ELEM_LAST_FIELD flags
  
  static int map_lookup_and_delete_elem(union bpf_attr *attr)
  {
  	void __user *ukey = u64_to_user_ptr(attr->key);
  	void __user *uvalue = u64_to_user_ptr(attr->value);
  	int ufd = attr->map_fd;
  	struct bpf_map *map;
  	void *key, *value;
  	u32 value_size;
  	struct fd f;
  	int err;
  
  	if (CHECK_ATTR(BPF_MAP_LOOKUP_AND_DELETE_ELEM))
  		return -EINVAL;
  
  	if (attr->flags & ~BPF_F_LOCK)
  		return -EINVAL;
  
  	f = fdget(ufd);
  	map = __bpf_map_get(f);
  	if (IS_ERR(map))
  		return PTR_ERR(map);
  	bpf_map_write_active_inc(map);
  	if (!(map_get_sys_perms(map, f) & FMODE_CAN_READ) ||
  	    !(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) {
  		err = -EPERM;
  		goto err_put;
  	}
  
  	if (attr->flags &&
  	    (map->map_type == BPF_MAP_TYPE_QUEUE ||
  	     map->map_type == BPF_MAP_TYPE_STACK)) {
  		err = -EINVAL;
  		goto err_put;
  	}
  
  	if ((attr->flags & BPF_F_LOCK) &&
  	    !map_value_has_spin_lock(map)) {
  		err = -EINVAL;
  		goto err_put;
  	}
  
  	key = __bpf_copy_key(ukey, map->key_size);
  	if (IS_ERR(key)) {
  		err = PTR_ERR(key);
  		goto err_put;
  	}
  
  	value_size = bpf_map_value_size(map);
  
  	err = -ENOMEM;
  	value = kvmalloc(value_size, GFP_USER | __GFP_NOWARN);
  	if (!value)
  		goto free_key;
  
  	err = -ENOTSUPP;
  	if (map->map_type == BPF_MAP_TYPE_QUEUE ||
  	    map->map_type == BPF_MAP_TYPE_STACK) {
  		err = map->ops->map_pop_elem(map, value);
  	} else if (map->map_type == BPF_MAP_TYPE_HASH ||
  		   map->map_type == BPF_MAP_TYPE_PERCPU_HASH ||
  		   map->map_type == BPF_MAP_TYPE_LRU_HASH ||
  		   map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH) {
  		if (!bpf_map_is_dev_bound(map)) {
  			bpf_disable_instrumentation();
  			rcu_read_lock();
  			err = map->ops->map_lookup_and_delete_elem(map, key, value, attr->flags);
  			rcu_read_unlock();
  			bpf_enable_instrumentation();
  		}
  	}
  
  	if (err)
  		goto free_value;
  
  	if (copy_to_user(uvalue, value, value_size) != 0) {
  		err = -EFAULT;
  		goto free_value;
  	}
  
  	err = 0;
  
  free_value:
  	kvfree(value);
  free_key:
  	kvfree(key);
  err_put:
  	bpf_map_write_active_dec(map);
  	fdput(f);
  	return err;
  }
  
  #define BPF_MAP_FREEZE_LAST_FIELD map_fd
  
  static int map_freeze(const union bpf_attr *attr)
  {
  	int err = 0, ufd = attr->map_fd;
  	struct bpf_map *map;
  	struct fd f;
  
  	if (CHECK_ATTR(BPF_MAP_FREEZE))
  		return -EINVAL;
  
  	f = fdget(ufd);
  	map = __bpf_map_get(f);
  	if (IS_ERR(map))
  		return PTR_ERR(map);
  
  	if (map->map_type == BPF_MAP_TYPE_STRUCT_OPS ||
  	    map_value_has_timer(map)) {
  		fdput(f);
  		return -ENOTSUPP;
  	}
  
  	mutex_lock(&map->freeze_mutex);
  	if (bpf_map_write_active(map)) {
  		err = -EBUSY;
  		goto err_put;
  	}
  	if (READ_ONCE(map->frozen)) {
  		err = -EBUSY;
  		goto err_put;
  	}
  	if (!bpf_capable()) {
  		err = -EPERM;
  		goto err_put;
  	}
  
  	WRITE_ONCE(map->frozen, true);
  err_put:
  	mutex_unlock(&map->freeze_mutex);
  	fdput(f);
  	return err;
  }
  
  static const struct bpf_prog_ops * const bpf_prog_types[] = {
  #define BPF_PROG_TYPE(_id, _name, prog_ctx_type, kern_ctx_type) \
  	[_id] = & _name ## _prog_ops,
  #define BPF_MAP_TYPE(_id, _ops)
  #define BPF_LINK_TYPE(_id, _name)
  #include <linux/bpf_types.h>
  #undef BPF_PROG_TYPE
  #undef BPF_MAP_TYPE
  #undef BPF_LINK_TYPE
  };
  
  static int find_prog_type(enum bpf_prog_type type, struct bpf_prog *prog)
  {
  	const struct bpf_prog_ops *ops;
  
  	if (type >= ARRAY_SIZE(bpf_prog_types))
  		return -EINVAL;
  	type = array_index_nospec(type, ARRAY_SIZE(bpf_prog_types));
  	ops = bpf_prog_types[type];
  	if (!ops)
  		return -EINVAL;
  
  	if (!bpf_prog_is_dev_bound(prog->aux))
  		prog->aux->ops = ops;
  	else
  		prog->aux->ops = &bpf_offload_prog_ops;
  	prog->type = type;
  	return 0;
  }
  
  enum bpf_audit {
  	BPF_AUDIT_LOAD,
  	BPF_AUDIT_UNLOAD,
  	BPF_AUDIT_MAX,
  };
  
  static const char * const bpf_audit_str[BPF_AUDIT_MAX] = {
  	[BPF_AUDIT_LOAD]   = "LOAD",
  	[BPF_AUDIT_UNLOAD] = "UNLOAD",
  };
  
  static void bpf_audit_prog(const struct bpf_prog *prog, unsigned int op)
  {
  	struct audit_context *ctx = NULL;
  	struct audit_buffer *ab;
  
  	if (WARN_ON_ONCE(op >= BPF_AUDIT_MAX))
  		return;
  	if (audit_enabled == AUDIT_OFF)
  		return;
  	if (op == BPF_AUDIT_LOAD)
  		ctx = audit_context();
  	ab = audit_log_start(ctx, GFP_ATOMIC, AUDIT_BPF);
  	if (unlikely(!ab))
  		return;
  	audit_log_format(ab, "prog-id=%u op=%s",
  			 prog->aux->id, bpf_audit_str[op]);
  	audit_log_end(ab);
  }
  
  static int bpf_prog_alloc_id(struct bpf_prog *prog)
  {
  	int id;
  
  	idr_preload(GFP_KERNEL);
  	spin_lock_bh(&prog_idr_lock);
  	id = idr_alloc_cyclic(&prog_idr, prog, 1, INT_MAX, GFP_ATOMIC);
  	if (id > 0)
  		prog->aux->id = id;
  	spin_unlock_bh(&prog_idr_lock);
  	idr_preload_end();
  
  	/* id is in [1, INT_MAX) */
  	if (WARN_ON_ONCE(!id))
  		return -ENOSPC;
  
  	return id > 0 ? 0 : id;
  }
  
  void bpf_prog_free_id(struct bpf_prog *prog, bool do_idr_lock)
  {
  	unsigned long flags;
  
  	/* cBPF to eBPF migrations are currently not in the idr store.
  	 * Offloaded programs are removed from the store when their device
  	 * disappears - even if someone grabs an fd to them they are unusable,
  	 * simply waiting for refcnt to drop to be freed.
  	 */
  	if (!prog->aux->id)
  		return;
  
  	if (do_idr_lock)
  		spin_lock_irqsave(&prog_idr_lock, flags);
  	else
  		__acquire(&prog_idr_lock);
  
  	idr_remove(&prog_idr, prog->aux->id);
  	prog->aux->id = 0;
  
  	if (do_idr_lock)
  		spin_unlock_irqrestore(&prog_idr_lock, flags);
  	else
  		__release(&prog_idr_lock);
  }
  
  static void __bpf_prog_put_rcu(struct rcu_head *rcu)
  {
  	struct bpf_prog_aux *aux = container_of(rcu, struct bpf_prog_aux, rcu);
  
  	kvfree(aux->func_info);
  	kfree(aux->func_info_aux);
  	free_uid(aux->user);
  	security_bpf_prog_free(aux);
  	bpf_prog_free(aux->prog);
  }
  
  static void __bpf_prog_put_noref(struct bpf_prog *prog, bool deferred)
  {
  	bpf_prog_kallsyms_del_all(prog);
  	btf_put(prog->aux->btf);
  	kvfree(prog->aux->jited_linfo);
  	kvfree(prog->aux->linfo);
  	kfree(prog->aux->kfunc_tab);
  	if (prog->aux->attach_btf)
  		btf_put(prog->aux->attach_btf);
  
  	if (deferred) {
  		if (prog->aux->sleepable)
  			call_rcu_tasks_trace(&prog->aux->rcu, __bpf_prog_put_rcu);
  		else
  			call_rcu(&prog->aux->rcu, __bpf_prog_put_rcu);
  	} else {
  		__bpf_prog_put_rcu(&prog->aux->rcu);
  	}
  }
  
  static void bpf_prog_put_deferred(struct work_struct *work)
  {
  	struct bpf_prog_aux *aux;
  	struct bpf_prog *prog;
  
  	aux = container_of(work, struct bpf_prog_aux, work);
  	prog = aux->prog;
  	perf_event_bpf_event(prog, PERF_BPF_EVENT_PROG_UNLOAD, 0);
  	bpf_audit_prog(prog, BPF_AUDIT_UNLOAD);
  	__bpf_prog_put_noref(prog, true);
  }
  
  static void __bpf_prog_put(struct bpf_prog *prog, bool do_idr_lock)
  {
  	struct bpf_prog_aux *aux = prog->aux;
  
  	if (atomic64_dec_and_test(&aux->refcnt)) {
  		/* bpf_prog_free_id() must be called first */
  		bpf_prog_free_id(prog, do_idr_lock);
  
  		if (in_irq() || irqs_disabled()) {
  			INIT_WORK(&aux->work, bpf_prog_put_deferred);
  			schedule_work(&aux->work);
  		} else {
  			bpf_prog_put_deferred(&aux->work);
  		}
  	}
  }
  
  void bpf_prog_put(struct bpf_prog *prog)
  {
  	__bpf_prog_put(prog, true);
  }
  EXPORT_SYMBOL_GPL(bpf_prog_put);
  
  static int bpf_prog_release(struct inode *inode, struct file *filp)
  {
  	struct bpf_prog *prog = filp->private_data;
  
  	bpf_prog_put(prog);
  	return 0;
  }
  
  struct bpf_prog_kstats {
  	u64 nsecs;
  	u64 cnt;
  	u64 misses;
  };
  
  static void bpf_prog_get_stats(const struct bpf_prog *prog,
  			       struct bpf_prog_kstats *stats)
  {
  	u64 nsecs = 0, cnt = 0, misses = 0;
  	int cpu;
  
  	for_each_possible_cpu(cpu) {
  		const struct bpf_prog_stats *st;
  		unsigned int start;
  		u64 tnsecs, tcnt, tmisses;
  
  		st = per_cpu_ptr(prog->stats, cpu);
  		do {
  			start = u64_stats_fetch_begin_irq(&st->syncp);
  			tnsecs = u64_stats_read(&st->nsecs);
  			tcnt = u64_stats_read(&st->cnt);
  			tmisses = u64_stats_read(&st->misses);
  		} while (u64_stats_fetch_retry_irq(&st->syncp, start));
  		nsecs += tnsecs;
  		cnt += tcnt;
  		misses += tmisses;
  	}
  	stats->nsecs = nsecs;
  	stats->cnt = cnt;
  	stats->misses = misses;
  }
  
  #ifdef CONFIG_PROC_FS
  static void bpf_prog_show_fdinfo(struct seq_file *m, struct file *filp)
  {
  	const struct bpf_prog *prog = filp->private_data;
  	char prog_tag[sizeof(prog->tag) * 2 + 1] = { };
  	struct bpf_prog_kstats stats;
  
  	bpf_prog_get_stats(prog, &stats);
  	bin2hex(prog_tag, prog->tag, sizeof(prog->tag));
  	seq_printf(m,
  		   "prog_type:\t%u\n"
  		   "prog_jited:\t%u\n"
  		   "prog_tag:\t%s\n"
  		   "memlock:\t%llu\n"
  		   "prog_id:\t%u\n"
  		   "run_time_ns:\t%llu\n"
  		   "run_cnt:\t%llu\n"
  		   "recursion_misses:\t%llu\n"
  		   "verified_insns:\t%u\n",
  		   prog->type,
  		   prog->jited,
  		   prog_tag,
  		   prog->pages * 1ULL << PAGE_SHIFT,
  		   prog->aux->id,
  		   stats.nsecs,
  		   stats.cnt,
  		   stats.misses,
  		   prog->aux->verified_insns);
  }
  #endif
  
  const struct file_operations bpf_prog_fops = {
  #ifdef CONFIG_PROC_FS
  	.show_fdinfo	= bpf_prog_show_fdinfo,
  #endif
  	.release	= bpf_prog_release,
  	.read		= bpf_dummy_read,
  	.write		= bpf_dummy_write,
  };
  
  int bpf_prog_new_fd(struct bpf_prog *prog)
  {
  	int ret;
  
  	ret = security_bpf_prog(prog);
  	if (ret < 0)
  		return ret;
  
  	return anon_inode_getfd("bpf-prog", &bpf_prog_fops, prog,
  				O_RDWR | O_CLOEXEC);
  }
  
  static struct bpf_prog *____bpf_prog_get(struct fd f)
  {
  	if (!f.file)
  		return ERR_PTR(-EBADF);
  	if (f.file->f_op != &bpf_prog_fops) {
  		fdput(f);
  		return ERR_PTR(-EINVAL);
  	}
  
  	return f.file->private_data;
  }
  
  void bpf_prog_add(struct bpf_prog *prog, int i)
  {
  	atomic64_add(i, &prog->aux->refcnt);
  }
  EXPORT_SYMBOL_GPL(bpf_prog_add);
  
  void bpf_prog_sub(struct bpf_prog *prog, int i)
  {
  	/* Only to be used for undoing previous bpf_prog_add() in some
  	 * error path. We still know that another entity in our call
  	 * path holds a reference to the program, thus atomic_sub() can
  	 * be safely used in such cases!
  	 */
  	WARN_ON(atomic64_sub_return(i, &prog->aux->refcnt) == 0);
  }
  EXPORT_SYMBOL_GPL(bpf_prog_sub);
  
  void bpf_prog_inc(struct bpf_prog *prog)
  {
  	atomic64_inc(&prog->aux->refcnt);
  }
  EXPORT_SYMBOL_GPL(bpf_prog_inc);
  
  /* prog_idr_lock should have been held */
  struct bpf_prog *bpf_prog_inc_not_zero(struct bpf_prog *prog)
  {
  	int refold;
  
  	refold = atomic64_fetch_add_unless(&prog->aux->refcnt, 1, 0);
  
  	if (!refold)
  		return ERR_PTR(-ENOENT);
  
  	return prog;
  }
  EXPORT_SYMBOL_GPL(bpf_prog_inc_not_zero);
  
  bool bpf_prog_get_ok(struct bpf_prog *prog,
  			    enum bpf_prog_type *attach_type, bool attach_drv)
  {
  	/* not an attachment, just a refcount inc, always allow */
  	if (!attach_type)
  		return true;
  
  	if (prog->type != *attach_type)
  		return false;
  	if (bpf_prog_is_dev_bound(prog->aux) && !attach_drv)
  		return false;
  
  	return true;
  }
  
  static struct bpf_prog *__bpf_prog_get(u32 ufd, enum bpf_prog_type *attach_type,
  				       bool attach_drv)
  {
  	struct fd f = fdget(ufd);
  	struct bpf_prog *prog;
  
  	prog = ____bpf_prog_get(f);
  	if (IS_ERR(prog))
  		return prog;
  	if (!bpf_prog_get_ok(prog, attach_type, attach_drv)) {
  		prog = ERR_PTR(-EINVAL);
  		goto out;
  	}
  
  	bpf_prog_inc(prog);
  out:
  	fdput(f);
  	return prog;
  }
  
  struct bpf_prog *bpf_prog_get(u32 ufd)
  {
  	return __bpf_prog_get(ufd, NULL, false);
  }
  
  struct bpf_prog *bpf_prog_get_type_dev(u32 ufd, enum bpf_prog_type type,
  				       bool attach_drv)
  {
  	return __bpf_prog_get(ufd, &type, attach_drv);
  }
  EXPORT_SYMBOL_GPL(bpf_prog_get_type_dev);
  
  /* Initially all BPF programs could be loaded w/o specifying
   * expected_attach_type. Later for some of them specifying expected_attach_type
   * at load time became required so that program could be validated properly.
   * Programs of types that are allowed to be loaded both w/ and w/o (for
   * backward compatibility) expected_attach_type, should have the default attach
   * type assigned to expected_attach_type for the latter case, so that it can be
   * validated later at attach time.
   *
   * bpf_prog_load_fixup_attach_type() sets expected_attach_type in @attr if
   * prog type requires it but has some attach types that have to be backward
   * compatible.
   */
  static void bpf_prog_load_fixup_attach_type(union bpf_attr *attr)
  {
  	switch (attr->prog_type) {
  	case BPF_PROG_TYPE_CGROUP_SOCK:
  		/* Unfortunately BPF_ATTACH_TYPE_UNSPEC enumeration doesn't
  		 * exist so checking for non-zero is the way to go here.
  		 */
  		if (!attr->expected_attach_type)
  			attr->expected_attach_type =
  				BPF_CGROUP_INET_SOCK_CREATE;
  		break;
  	case BPF_PROG_TYPE_SK_REUSEPORT:
  		if (!attr->expected_attach_type)
  			attr->expected_attach_type =
  				BPF_SK_REUSEPORT_SELECT;
  		break;
  	}
  }
  
  static int
  bpf_prog_load_check_attach(enum bpf_prog_type prog_type,
  			   enum bpf_attach_type expected_attach_type,
  			   struct btf *attach_btf, u32 btf_id,
  			   struct bpf_prog *dst_prog)
  {
  	if (btf_id) {
  		if (btf_id > BTF_MAX_TYPE)
  			return -EINVAL;
  
  		if (!attach_btf && !dst_prog)
  			return -EINVAL;
  
  		switch (prog_type) {
  		case BPF_PROG_TYPE_TRACING:
  		case BPF_PROG_TYPE_LSM:
  		case BPF_PROG_TYPE_STRUCT_OPS:
  		case BPF_PROG_TYPE_EXT:
  			break;
  		default:
  			return -EINVAL;
  		}
  	}
  
  	if (attach_btf && (!btf_id || dst_prog))
  		return -EINVAL;
  
  	if (dst_prog && prog_type != BPF_PROG_TYPE_TRACING &&
  	    prog_type != BPF_PROG_TYPE_EXT)
  		return -EINVAL;
  
  	switch (prog_type) {
  	case BPF_PROG_TYPE_CGROUP_SOCK:
  		switch (expected_attach_type) {
  		case BPF_CGROUP_INET_SOCK_CREATE:
  		case BPF_CGROUP_INET_SOCK_RELEASE:
  		case BPF_CGROUP_INET4_POST_BIND:
  		case BPF_CGROUP_INET6_POST_BIND:
  			return 0;
  		default:
  			return -EINVAL;
  		}
  	case BPF_PROG_TYPE_CGROUP_SOCK_ADDR:
  		switch (expected_attach_type) {
  		case BPF_CGROUP_INET4_BIND:
  		case BPF_CGROUP_INET6_BIND:
  		case BPF_CGROUP_INET4_CONNECT:
  		case BPF_CGROUP_INET6_CONNECT:
  		case BPF_CGROUP_INET4_GETPEERNAME:
  		case BPF_CGROUP_INET6_GETPEERNAME:
  		case BPF_CGROUP_INET4_GETSOCKNAME:
  		case BPF_CGROUP_INET6_GETSOCKNAME:
  		case BPF_CGROUP_UDP4_SENDMSG:
  		case BPF_CGROUP_UDP6_SENDMSG:
  		case BPF_CGROUP_UDP4_RECVMSG:
  		case BPF_CGROUP_UDP6_RECVMSG:
  			return 0;
  		default:
  			return -EINVAL;
  		}
  	case BPF_PROG_TYPE_CGROUP_SKB:
  		switch (expected_attach_type) {
  		case BPF_CGROUP_INET_INGRESS:
  		case BPF_CGROUP_INET_EGRESS:
  			return 0;
  		default:
  			return -EINVAL;
  		}
  	case BPF_PROG_TYPE_CGROUP_SOCKOPT:
  		switch (expected_attach_type) {
  		case BPF_CGROUP_SETSOCKOPT:
  		case BPF_CGROUP_GETSOCKOPT:
  			return 0;
  		default:
  			return -EINVAL;
  		}
  	case BPF_PROG_TYPE_SK_LOOKUP:
  		if (expected_attach_type == BPF_SK_LOOKUP)
  			return 0;
  		return -EINVAL;
  	case BPF_PROG_TYPE_SK_REUSEPORT:
  		switch (expected_attach_type) {
  		case BPF_SK_REUSEPORT_SELECT:
  		case BPF_SK_REUSEPORT_SELECT_OR_MIGRATE:
  			return 0;
  		default:
  			return -EINVAL;
  		}
  	case BPF_PROG_TYPE_SYSCALL:
  	case BPF_PROG_TYPE_EXT:
  		if (expected_attach_type)
  			return -EINVAL;
  		fallthrough;
  	default:
  		return 0;
  	}
  }
  
  static bool is_net_admin_prog_type(enum bpf_prog_type prog_type)
  {
  	switch (prog_type) {
  	case BPF_PROG_TYPE_SCHED_CLS:
  	case BPF_PROG_TYPE_SCHED_ACT:
  	case BPF_PROG_TYPE_XDP:
  	case BPF_PROG_TYPE_LWT_IN:
  	case BPF_PROG_TYPE_LWT_OUT:
  	case BPF_PROG_TYPE_LWT_XMIT:
  	case BPF_PROG_TYPE_LWT_SEG6LOCAL:
  	case BPF_PROG_TYPE_SK_SKB:
  	case BPF_PROG_TYPE_SK_MSG:
  	case BPF_PROG_TYPE_LIRC_MODE2:
  	case BPF_PROG_TYPE_FLOW_DISSECTOR:
  	case BPF_PROG_TYPE_CGROUP_DEVICE:
  	case BPF_PROG_TYPE_CGROUP_SOCK:
  	case BPF_PROG_TYPE_CGROUP_SOCK_ADDR:
  	case BPF_PROG_TYPE_CGROUP_SOCKOPT:
  	case BPF_PROG_TYPE_CGROUP_SYSCTL:
  	case BPF_PROG_TYPE_SOCK_OPS:
  	case BPF_PROG_TYPE_EXT: /* extends any prog */
  		return true;
  	case BPF_PROG_TYPE_CGROUP_SKB:
  		/* always unpriv */
  	case BPF_PROG_TYPE_SK_REUSEPORT:
  		/* equivalent to SOCKET_FILTER. need CAP_BPF only */
  	default:
  		return false;
  	}
  }
  
  static bool is_perfmon_prog_type(enum bpf_prog_type prog_type)
  {
  	switch (prog_type) {
  	case BPF_PROG_TYPE_KPROBE:
  	case BPF_PROG_TYPE_TRACEPOINT:
  	case BPF_PROG_TYPE_PERF_EVENT:
  	case BPF_PROG_TYPE_RAW_TRACEPOINT:
  	case BPF_PROG_TYPE_RAW_TRACEPOINT_WRITABLE:
  	case BPF_PROG_TYPE_TRACING:
  	case BPF_PROG_TYPE_LSM:
  	case BPF_PROG_TYPE_STRUCT_OPS: /* has access to struct sock */
  	case BPF_PROG_TYPE_EXT: /* extends any prog */
  		return true;
  	default:
  		return false;
  	}
  }
  
  /* last field in 'union bpf_attr' used by this command */
  #define	BPF_PROG_LOAD_LAST_FIELD core_relo_rec_size
  
  static int bpf_prog_load(union bpf_attr *attr, bpfptr_t uattr)
  {
  	enum bpf_prog_type type = attr->prog_type;
  	struct bpf_prog *prog, *dst_prog = NULL;
  	struct btf *attach_btf = NULL;
  	int err;
  	char license[128];
  	bool is_gpl;
  
  	if (CHECK_ATTR(BPF_PROG_LOAD))
  		return -EINVAL;
  
  	if (attr->prog_flags & ~(BPF_F_STRICT_ALIGNMENT |
  				 BPF_F_ANY_ALIGNMENT |
  				 BPF_F_TEST_STATE_FREQ |
  				 BPF_F_SLEEPABLE |
  				 BPF_F_TEST_RND_HI32 |
  				 BPF_F_XDP_HAS_FRAGS))
  		return -EINVAL;
  
  	if (!IS_ENABLED(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) &&
  	    (attr->prog_flags & BPF_F_ANY_ALIGNMENT) &&
  	    !bpf_capable())
  		return -EPERM;
  
  	/* copy eBPF program license from user space */
  	if (strncpy_from_bpfptr(license,
  				make_bpfptr(attr->license, uattr.is_kernel),
  				sizeof(license) - 1) < 0)
  		return -EFAULT;
  	license[sizeof(license) - 1] = 0;
  
  	/* eBPF programs must be GPL compatible to use GPL-ed functions */
  	is_gpl = license_is_gpl_compatible(license);
  
  	if (attr->insn_cnt == 0 ||
  	    attr->insn_cnt > (bpf_capable() ? BPF_COMPLEXITY_LIMIT_INSNS : BPF_MAXINSNS))
  		return -E2BIG;
  	if (type != BPF_PROG_TYPE_SOCKET_FILTER &&
  	    type != BPF_PROG_TYPE_CGROUP_SKB &&
  	    !bpf_capable())
  		return -EPERM;
  
  	if (is_net_admin_prog_type(type) && !capable(CAP_NET_ADMIN) && !capable(CAP_SYS_ADMIN))
  		return -EPERM;
  	if (is_perfmon_prog_type(type) && !perfmon_capable())
  		return -EPERM;
  
  	/* attach_prog_fd/attach_btf_obj_fd can specify fd of either bpf_prog
  	 * or btf, we need to check which one it is
  	 */
  	if (attr->attach_prog_fd) {
  		dst_prog = bpf_prog_get(attr->attach_prog_fd);
  		if (IS_ERR(dst_prog)) {
  			dst_prog = NULL;
  			attach_btf = btf_get_by_fd(attr->attach_btf_obj_fd);
  			if (IS_ERR(attach_btf))
  				return -EINVAL;
  			if (!btf_is_kernel(attach_btf)) {
  				/* attaching through specifying bpf_prog's BTF
  				 * objects directly might be supported eventually
  				 */
  				btf_put(attach_btf);
  				return -ENOTSUPP;
  			}
  		}
  	} else if (attr->attach_btf_id) {
  		/* fall back to vmlinux BTF, if BTF type ID is specified */
  		attach_btf = bpf_get_btf_vmlinux();
  		if (IS_ERR(attach_btf))
  			return PTR_ERR(attach_btf);
  		if (!attach_btf)
  			return -EINVAL;
  		btf_get(attach_btf);
  	}
  
  	bpf_prog_load_fixup_attach_type(attr);
  	if (bpf_prog_load_check_attach(type, attr->expected_attach_type,
  				       attach_btf, attr->attach_btf_id,
  				       dst_prog)) {
  		if (dst_prog)
  			bpf_prog_put(dst_prog);
  		if (attach_btf)
  			btf_put(attach_btf);
  		return -EINVAL;
  	}
  
  	/* plain bpf_prog allocation */
  	prog = bpf_prog_alloc(bpf_prog_size(attr->insn_cnt), GFP_USER);
  	if (!prog) {
  		if (dst_prog)
  			bpf_prog_put(dst_prog);
  		if (attach_btf)
  			btf_put(attach_btf);
  		return -ENOMEM;
  	}
  
  	prog->expected_attach_type = attr->expected_attach_type;
  	prog->aux->attach_btf = attach_btf;
  	prog->aux->attach_btf_id = attr->attach_btf_id;
  	prog->aux->dst_prog = dst_prog;
  	prog->aux->offload_requested = !!attr->prog_ifindex;
  	prog->aux->sleepable = attr->prog_flags & BPF_F_SLEEPABLE;
  	prog->aux->xdp_has_frags = attr->prog_flags & BPF_F_XDP_HAS_FRAGS;
  
  	err = security_bpf_prog_alloc(prog->aux);
  	if (err)
  		goto free_prog;
  
  	prog->aux->user = get_current_user();
  	prog->len = attr->insn_cnt;
  
  	err = -EFAULT;
  	if (copy_from_bpfptr(prog->insns,
  			     make_bpfptr(attr->insns, uattr.is_kernel),
  			     bpf_prog_insn_size(prog)) != 0)
  		goto free_prog_sec;
  
  	prog->orig_prog = NULL;
  	prog->jited = 0;
  
  	atomic64_set(&prog->aux->refcnt, 1);
  	prog->gpl_compatible = is_gpl ? 1 : 0;
  
  	if (bpf_prog_is_dev_bound(prog->aux)) {
  		err = bpf_prog_offload_init(prog, attr);
  		if (err)
  			goto free_prog_sec;
  	}
  
  	/* find program type: socket_filter vs tracing_filter */
  	err = find_prog_type(type, prog);
  	if (err < 0)
  		goto free_prog_sec;
  
  	prog->aux->load_time = ktime_get_boottime_ns();
  	err = bpf_obj_name_cpy(prog->aux->name, attr->prog_name,
  			       sizeof(attr->prog_name));
  	if (err < 0)
  		goto free_prog_sec;
  
  	/* run eBPF verifier */
  	err = bpf_check(&prog, attr, uattr);
  	if (err < 0)
  		goto free_used_maps;
  
  	prog = bpf_prog_select_runtime(prog, &err);
  	if (err < 0)
  		goto free_used_maps;
  
  	err = bpf_prog_alloc_id(prog);
  	if (err)
  		goto free_used_maps;
  
  	/* Upon success of bpf_prog_alloc_id(), the BPF prog is
  	 * effectively publicly exposed. However, retrieving via
  	 * bpf_prog_get_fd_by_id() will take another reference,
  	 * therefore it cannot be gone underneath us.
  	 *
  	 * Only for the time /after/ successful bpf_prog_new_fd()
  	 * and before returning to userspace, we might just hold
  	 * one reference and any parallel close on that fd could
  	 * rip everything out. Hence, below notifications must
  	 * happen before bpf_prog_new_fd().
  	 *
  	 * Also, any failure handling from this point onwards must
  	 * be using bpf_prog_put() given the program is exposed.
  	 */
  	bpf_prog_kallsyms_add(prog);
  	perf_event_bpf_event(prog, PERF_BPF_EVENT_PROG_LOAD, 0);
  	bpf_audit_prog(prog, BPF_AUDIT_LOAD);
  
  	err = bpf_prog_new_fd(prog);
  	if (err < 0)
  		bpf_prog_put(prog);
  	return err;
  
  free_used_maps:
  	/* In case we have subprogs, we need to wait for a grace
  	 * period before we can tear down JIT memory since symbols
  	 * are already exposed under kallsyms.
  	 */
  	__bpf_prog_put_noref(prog, prog->aux->func_cnt);
  	return err;
  free_prog_sec:
  	free_uid(prog->aux->user);
  	security_bpf_prog_free(prog->aux);
  free_prog:
  	if (prog->aux->attach_btf)
  		btf_put(prog->aux->attach_btf);
  	bpf_prog_free(prog);
  	return err;
  }
  
  #define BPF_OBJ_LAST_FIELD file_flags
  
  static int bpf_obj_pin(const union bpf_attr *attr)
  {
  	if (CHECK_ATTR(BPF_OBJ) || attr->file_flags != 0)
  		return -EINVAL;
  
  	return bpf_obj_pin_user(attr->bpf_fd, u64_to_user_ptr(attr->pathname));
  }
  
  static int bpf_obj_get(const union bpf_attr *attr)
  {
  	if (CHECK_ATTR(BPF_OBJ) || attr->bpf_fd != 0 ||
  	    attr->file_flags & ~BPF_OBJ_FLAG_MASK)
  		return -EINVAL;
  
  	return bpf_obj_get_user(u64_to_user_ptr(attr->pathname),
  				attr->file_flags);
  }
  
  void bpf_link_init(struct bpf_link *link, enum bpf_link_type type,
  		   const struct bpf_link_ops *ops, struct bpf_prog *prog)
  {
  	atomic64_set(&link->refcnt, 1);
  	link->type = type;
  	link->id = 0;
  	link->ops = ops;
  	link->prog = prog;
  }
  
  static void bpf_link_free_id(int id)
  {
  	if (!id)
  		return;
  
  	spin_lock_bh(&link_idr_lock);
  	idr_remove(&link_idr, id);
  	spin_unlock_bh(&link_idr_lock);
  }
  
  /* Clean up bpf_link and corresponding anon_inode file and FD. After
   * anon_inode is created, bpf_link can't be just kfree()'d due to deferred
   * anon_inode's release() call. This helper marksbpf_link as
   * defunct, releases anon_inode file and puts reserved FD. bpf_prog's refcnt
   * is not decremented, it's the responsibility of a calling code that failed
   * to complete bpf_link initialization.
   */
  void bpf_link_cleanup(struct bpf_link_primer *primer)
  {
  	primer->link->prog = NULL;
  	bpf_link_free_id(primer->id);
  	fput(primer->file);
  	put_unused_fd(primer->fd);
  }
  
  void bpf_link_inc(struct bpf_link *link)
  {
  	atomic64_inc(&link->refcnt);
  }
  
  /* bpf_link_free is guaranteed to be called from process context */
  static void bpf_link_free(struct bpf_link *link)
  {
  	bpf_link_free_id(link->id);
  	if (link->prog) {
  		/* detach BPF program, clean up used resources */
  		link->ops->release(link);
  		bpf_prog_put(link->prog);
  	}
  	/* free bpf_link and its containing memory */
  	link->ops->dealloc(link);
  }
  
  static void bpf_link_put_deferred(struct work_struct *work)
  {
  	struct bpf_link *link = container_of(work, struct bpf_link, work);
  
  	bpf_link_free(link);
  }
  
  /* bpf_link_put can be called from atomic context, but ensures that resources
   * are freed from process context
   */
  void bpf_link_put(struct bpf_link *link)
  {
  	if (!atomic64_dec_and_test(&link->refcnt))
  		return;
  
  	if (in_atomic()) {
  		INIT_WORK(&link->work, bpf_link_put_deferred);
  		schedule_work(&link->work);
  	} else {
  		bpf_link_free(link);
  	}
  }
  EXPORT_SYMBOL(bpf_link_put);
  
  static int bpf_link_release(struct inode *inode, struct file *filp)
  {
  	struct bpf_link *link = filp->private_data;
  
  	bpf_link_put(link);
  	return 0;
  }
  
  #ifdef CONFIG_PROC_FS
  #define BPF_PROG_TYPE(_id, _name, prog_ctx_type, kern_ctx_type)
  #define BPF_MAP_TYPE(_id, _ops)
  #define BPF_LINK_TYPE(_id, _name) [_id] = #_name,
  static const char *bpf_link_type_strs[] = {
  	[BPF_LINK_TYPE_UNSPEC] = "<invalid>",
  #include <linux/bpf_types.h>
  };
  #undef BPF_PROG_TYPE
  #undef BPF_MAP_TYPE
  #undef BPF_LINK_TYPE
  
  static void bpf_link_show_fdinfo(struct seq_file *m, struct file *filp)
  {
  	const struct bpf_link *link = filp->private_data;
  	const struct bpf_prog *prog = link->prog;
  	char prog_tag[sizeof(prog->tag) * 2 + 1] = { };
  
  	bin2hex(prog_tag, prog->tag, sizeof(prog->tag));
  	seq_printf(m,
  		   "link_type:\t%s\n"
  		   "link_id:\t%u\n"
  		   "prog_tag:\t%s\n"
  		   "prog_id:\t%u\n",
  		   bpf_link_type_strs[link->type],
  		   link->id,
  		   prog_tag,
  		   prog->aux->id);
  	if (link->ops->show_fdinfo)
  		link->ops->show_fdinfo(link, m);
  }
  #endif
  
  static const struct file_operations bpf_link_fops = {
  #ifdef CONFIG_PROC_FS
  	.show_fdinfo	= bpf_link_show_fdinfo,
  #endif
  	.release	= bpf_link_release,
  	.read		= bpf_dummy_read,
  	.write		= bpf_dummy_write,
  };
  
  static int bpf_link_alloc_id(struct bpf_link *link)
  {
  	int id;
  
  	idr_preload(GFP_KERNEL);
  	spin_lock_bh(&link_idr_lock);
  	id = idr_alloc_cyclic(&link_idr, link, 1, INT_MAX, GFP_ATOMIC);
  	spin_unlock_bh(&link_idr_lock);
  	idr_preload_end();
  
  	return id;
  }
  
  /* Prepare bpf_link to be exposed to user-space by allocating anon_inode file,
   * reserving unused FD and allocating ID from link_idr. This is to be paired
   * with bpf_link_settle() to install FD and ID and expose bpf_link to
   * user-space, if bpf_link is successfully attached. If not, bpf_link and
   * pre-allocated resources are to be freed with bpf_cleanup() call. All the
   * transient state is passed around in struct bpf_link_primer.
   * This is preferred way to create and initialize bpf_link, especially when
   * there are complicated and expensive operations in between creating bpf_link
   * itself and attaching it to BPF hook. By using bpf_link_prime() and
   * bpf_link_settle() kernel code using bpf_link doesn't have to perform
   * expensive (and potentially failing) roll back operations in a rare case
   * that file, FD, or ID can't be allocated.
   */
  int bpf_link_prime(struct bpf_link *link, struct bpf_link_primer *primer)
  {
  	struct file *file;
  	int fd, id;
  
  	fd = get_unused_fd_flags(O_CLOEXEC);
  	if (fd < 0)
  		return fd;
  
  
  	id = bpf_link_alloc_id(link);
  	if (id < 0) {
  		put_unused_fd(fd);
  		return id;
  	}
  
  	file = anon_inode_getfile("bpf_link", &bpf_link_fops, link, O_CLOEXEC);
  	if (IS_ERR(file)) {
  		bpf_link_free_id(id);
  		put_unused_fd(fd);
  		return PTR_ERR(file);
  	}
  
  	primer->link = link;
  	primer->file = file;
  	primer->fd = fd;
  	primer->id = id;
  	return 0;
  }
  
  int bpf_link_settle(struct bpf_link_primer *primer)
  {
  	/* make bpf_link fetchable by ID */
  	spin_lock_bh(&link_idr_lock);
  	primer->link->id = primer->id;
  	spin_unlock_bh(&link_idr_lock);
  	/* make bpf_link fetchable by FD */
  	fd_install(primer->fd, primer->file);
  	/* pass through installed FD */
  	return primer->fd;
  }
  
  int bpf_link_new_fd(struct bpf_link *link)
  {
  	return anon_inode_getfd("bpf-link", &bpf_link_fops, link, O_CLOEXEC);
  }
  
  struct bpf_link *bpf_link_get_from_fd(u32 ufd)
  {
  	struct fd f = fdget(ufd);
  	struct bpf_link *link;
  
  	if (!f.file)
  		return ERR_PTR(-EBADF);
  	if (f.file->f_op != &bpf_link_fops) {
  		fdput(f);
  		return ERR_PTR(-EINVAL);
  	}
  
  	link = f.file->private_data;
  	bpf_link_inc(link);
  	fdput(f);
  
  	return link;
  }
  EXPORT_SYMBOL(bpf_link_get_from_fd);
  
  struct bpf_tracing_link {
  	struct bpf_link link;
  	enum bpf_attach_type attach_type;
  	struct bpf_trampoline *trampoline;
  	struct bpf_prog *tgt_prog;
  };
  
  static void bpf_tracing_link_release(struct bpf_link *link)
  {
  	struct bpf_tracing_link *tr_link =
  		container_of(link, struct bpf_tracing_link, link);
  
  	WARN_ON_ONCE(bpf_trampoline_unlink_prog(link->prog,
  						tr_link->trampoline));
  
  	bpf_trampoline_put(tr_link->trampoline);
  
  	/* tgt_prog is NULL if target is a kernel function */
  	if (tr_link->tgt_prog)
  		bpf_prog_put(tr_link->tgt_prog);
  }
  
  static void bpf_tracing_link_dealloc(struct bpf_link *link)
  {
  	struct bpf_tracing_link *tr_link =
  		container_of(link, struct bpf_tracing_link, link);
  
  	kfree(tr_link);
  }
  
  static void bpf_tracing_link_show_fdinfo(const struct bpf_link *link,
  					 struct seq_file *seq)
  {
  	struct bpf_tracing_link *tr_link =
  		container_of(link, struct bpf_tracing_link, link);
  
  	seq_printf(seq,
  		   "attach_type:\t%d\n",
  		   tr_link->attach_type);
  }
  
  static int bpf_tracing_link_fill_link_info(const struct bpf_link *link,
  					   struct bpf_link_info *info)
  {
  	struct bpf_tracing_link *tr_link =
  		container_of(link, struct bpf_tracing_link, link);
  
  	info->tracing.attach_type = tr_link->attach_type;
  	bpf_trampoline_unpack_key(tr_link->trampoline->key,
  				  &info->tracing.target_obj_id,
  				  &info->tracing.target_btf_id);
  
  	return 0;
  }
  
  static const struct bpf_link_ops bpf_tracing_link_lops = {
  	.release = bpf_tracing_link_release,
  	.dealloc = bpf_tracing_link_dealloc,
  	.show_fdinfo = bpf_tracing_link_show_fdinfo,
  	.fill_link_info = bpf_tracing_link_fill_link_info,
  };
  
  static int bpf_tracing_prog_attach(struct bpf_prog *prog,
  				   int tgt_prog_fd,
  				   u32 btf_id)
  {
  	struct bpf_link_primer link_primer;
  	struct bpf_prog *tgt_prog = NULL;
  	struct bpf_trampoline *tr = NULL;
  	struct bpf_tracing_link *link;
  	u64 key = 0;
  	int err;
  
  	switch (prog->type) {
  	case BPF_PROG_TYPE_TRACING:
  		if (prog->expected_attach_type != BPF_TRACE_FENTRY &&
  		    prog->expected_attach_type != BPF_TRACE_FEXIT &&
  		    prog->expected_attach_type != BPF_MODIFY_RETURN) {
  			err = -EINVAL;
  			goto out_put_prog;
  		}
  		break;
  	case BPF_PROG_TYPE_EXT:
  		if (prog->expected_attach_type != 0) {
  			err = -EINVAL;
  			goto out_put_prog;
  		}
  		break;
  	case BPF_PROG_TYPE_LSM:
  		if (prog->expected_attach_type != BPF_LSM_MAC) {
  			err = -EINVAL;
  			goto out_put_prog;
  		}
  		break;
  	default:
  		err = -EINVAL;
  		goto out_put_prog;
  	}
  
  	if (!!tgt_prog_fd != !!btf_id) {
  		err = -EINVAL;
  		goto out_put_prog;
  	}
  
  	if (tgt_prog_fd) {
  		/* For now we only allow new targets for BPF_PROG_TYPE_EXT */
  		if (prog->type != BPF_PROG_TYPE_EXT) {
  			err = -EINVAL;
  			goto out_put_prog;
  		}
  
  		tgt_prog = bpf_prog_get(tgt_prog_fd);
  		if (IS_ERR(tgt_prog)) {
  			err = PTR_ERR(tgt_prog);
  			tgt_prog = NULL;
  			goto out_put_prog;
  		}
  
  		key = bpf_trampoline_compute_key(tgt_prog, NULL, btf_id);
  	}
  
  	link = kzalloc(sizeof(*link), GFP_USER);
  	if (!link) {
  		err = -ENOMEM;
  		goto out_put_prog;
  	}
  	bpf_link_init(&link->link, BPF_LINK_TYPE_TRACING,
  		      &bpf_tracing_link_lops, prog);
  	link->attach_type = prog->expected_attach_type;
  
  	mutex_lock(&prog->aux->dst_mutex);
  
  	/* There are a few possible cases here:
  	 *
  	 * - if prog->aux->dst_trampoline is set, the program was just loaded
  	 *   and not yet attached to anything, so we can use the values stored
  	 *   in prog->aux
  	 *
  	 * - if prog->aux->dst_trampoline is NULL, the program has already been
           *   attached to a target and its initial target was cleared (below)
  	 *
  	 * - if tgt_prog != NULL, the caller specified tgt_prog_fd +
  	 *   target_btf_id using the link_create API.
  	 *
  	 * - if tgt_prog == NULL when this function was called using the old
  	 *   raw_tracepoint_open API, and we need a target from prog->aux
  	 *
  	 * - if prog->aux->dst_trampoline and tgt_prog is NULL, the program
  	 *   was detached and is going for re-attachment.
  	 */
  	if (!prog->aux->dst_trampoline && !tgt_prog) {
  		/*
  		 * Allow re-attach for TRACING and LSM programs. If it's
  		 * currently linked, bpf_trampoline_link_prog will fail.
  		 * EXT programs need to specify tgt_prog_fd, so they
  		 * re-attach in separate code path.
  		 */
  		if (prog->type != BPF_PROG_TYPE_TRACING &&
  		    prog->type != BPF_PROG_TYPE_LSM) {
  			err = -EINVAL;
  			goto out_unlock;
  		}
  		btf_id = prog->aux->attach_btf_id;
  		key = bpf_trampoline_compute_key(NULL, prog->aux->attach_btf, btf_id);
  	}
  
  	if (!prog->aux->dst_trampoline ||
  	    (key && key != prog->aux->dst_trampoline->key)) {
  		/* If there is no saved target, or the specified target is
  		 * different from the destination specified at load time, we
  		 * need a new trampoline and a check for compatibility
  		 */
  		struct bpf_attach_target_info tgt_info = {};
  
  		err = bpf_check_attach_target(NULL, prog, tgt_prog, btf_id,
  					      &tgt_info);
  		if (err)
  			goto out_unlock;
  
  		tr = bpf_trampoline_get(key, &tgt_info);
  		if (!tr) {
  			err = -ENOMEM;
  			goto out_unlock;
  		}
  	} else {
  		/* The caller didn't specify a target, or the target was the
  		 * same as the destination supplied during program load. This
  		 * means we can reuse the trampoline and reference from program
  		 * load time, and there is no need to allocate a new one. This
  		 * can only happen once for any program, as the saved values in
  		 * prog->aux are cleared below.
  		 */
  		tr = prog->aux->dst_trampoline;
  		tgt_prog = prog->aux->dst_prog;
  	}
  
  	err = bpf_link_prime(&link->link, &link_primer);
  	if (err)
  		goto out_unlock;
  
  	err = bpf_trampoline_link_prog(prog, tr);
  	if (err) {
  		bpf_link_cleanup(&link_primer);
  		link = NULL;
  		goto out_unlock;
  	}
  
  	link->tgt_prog = tgt_prog;
  	link->trampoline = tr;
  
  	/* Always clear the trampoline and target prog from prog->aux to make
  	 * sure the original attach destination is not kept alive after a
  	 * program is (re-)attached to another target.
  	 */
  	if (prog->aux->dst_prog &&
  	    (tgt_prog_fd || tr != prog->aux->dst_trampoline))
  		/* got extra prog ref from syscall, or attaching to different prog */
  		bpf_prog_put(prog->aux->dst_prog);
  	if (prog->aux->dst_trampoline && tr != prog->aux->dst_trampoline)
  		/* we allocated a new trampoline, so free the old one */
  		bpf_trampoline_put(prog->aux->dst_trampoline);
  
  	prog->aux->dst_prog = NULL;
  	prog->aux->dst_trampoline = NULL;
  	mutex_unlock(&prog->aux->dst_mutex);
  
  	return bpf_link_settle(&link_primer);
  out_unlock:
  	if (tr && tr != prog->aux->dst_trampoline)
  		bpf_trampoline_put(tr);
  	mutex_unlock(&prog->aux->dst_mutex);
  	kfree(link);
  out_put_prog:
  	if (tgt_prog_fd && tgt_prog)
  		bpf_prog_put(tgt_prog);
  	return err;
  }
  
  struct bpf_raw_tp_link {
  	struct bpf_link link;
  	struct bpf_raw_event_map *btp;
  };
  
  static void bpf_raw_tp_link_release(struct bpf_link *link)
  {
  	struct bpf_raw_tp_link *raw_tp =
  		container_of(link, struct bpf_raw_tp_link, link);
  
  	bpf_probe_unregister(raw_tp->btp, raw_tp->link.prog);
  	bpf_put_raw_tracepoint(raw_tp->btp);
  }
  
  static void bpf_raw_tp_link_dealloc(struct bpf_link *link)
  {
  	struct bpf_raw_tp_link *raw_tp =
  		container_of(link, struct bpf_raw_tp_link, link);
  
  	kfree(raw_tp);
  }
  
  static void bpf_raw_tp_link_show_fdinfo(const struct bpf_link *link,
  					struct seq_file *seq)
  {
  	struct bpf_raw_tp_link *raw_tp_link =
  		container_of(link, struct bpf_raw_tp_link, link);
  
  	seq_printf(seq,
  		   "tp_name:\t%s\n",
  		   raw_tp_link->btp->tp->name);
  }
  
  static int bpf_raw_tp_link_fill_link_info(const struct bpf_link *link,
  					  struct bpf_link_info *info)
  {
  	struct bpf_raw_tp_link *raw_tp_link =
  		container_of(link, struct bpf_raw_tp_link, link);
  	char __user *ubuf = u64_to_user_ptr(info->raw_tracepoint.tp_name);
  	const char *tp_name = raw_tp_link->btp->tp->name;
  	u32 ulen = info->raw_tracepoint.tp_name_len;
  	size_t tp_len = strlen(tp_name);
  
  	if (!ulen ^ !ubuf)
  		return -EINVAL;
  
  	info->raw_tracepoint.tp_name_len = tp_len + 1;
  
  	if (!ubuf)
  		return 0;
  
  	if (ulen >= tp_len + 1) {
  		if (copy_to_user(ubuf, tp_name, tp_len + 1))
  			return -EFAULT;
  	} else {
  		char zero = '\0';
  
  		if (copy_to_user(ubuf, tp_name, ulen - 1))
  			return -EFAULT;
  		if (put_user(zero, ubuf + ulen - 1))
  			return -EFAULT;
  		return -ENOSPC;
  	}
  
  	return 0;
  }
  
  static const struct bpf_link_ops bpf_raw_tp_link_lops = {
  	.release = bpf_raw_tp_link_release,
  	.dealloc = bpf_raw_tp_link_dealloc,
  	.show_fdinfo = bpf_raw_tp_link_show_fdinfo,
  	.fill_link_info = bpf_raw_tp_link_fill_link_info,
  };
  
  #ifdef CONFIG_PERF_EVENTS
  struct bpf_perf_link {
  	struct bpf_link link;
  	struct file *perf_file;
  };
  
  static void bpf_perf_link_release(struct bpf_link *link)
  {
  	struct bpf_perf_link *perf_link = container_of(link, struct bpf_perf_link, link);
  	struct perf_event *event = perf_link->perf_file->private_data;
  
  	perf_event_free_bpf_prog(event);
  	fput(perf_link->perf_file);
  }
  
  static void bpf_perf_link_dealloc(struct bpf_link *link)
  {
  	struct bpf_perf_link *perf_link = container_of(link, struct bpf_perf_link, link);
  
  	kfree(perf_link);
  }
  
  static const struct bpf_link_ops bpf_perf_link_lops = {
  	.release = bpf_perf_link_release,
  	.dealloc = bpf_perf_link_dealloc,
  };
  
  static int bpf_perf_link_attach(const union bpf_attr *attr, struct bpf_prog *prog)
  {
  	struct bpf_link_primer link_primer;
  	struct bpf_perf_link *link;
  	struct perf_event *event;
  	struct file *perf_file;
  	int err;
  
  	if (attr->link_create.flags)
  		return -EINVAL;
  
  	perf_file = perf_event_get(attr->link_create.target_fd);
  	if (IS_ERR(perf_file))
  		return PTR_ERR(perf_file);
  
  	link = kzalloc(sizeof(*link), GFP_USER);
  	if (!link) {
  		err = -ENOMEM;
  		goto out_put_file;
  	}
  	bpf_link_init(&link->link, BPF_LINK_TYPE_PERF_EVENT, &bpf_perf_link_lops, prog);
  	link->perf_file = perf_file;
  
  	err = bpf_link_prime(&link->link, &link_primer);
  	if (err) {
  		kfree(link);
  		goto out_put_file;
  	}
  
  	event = perf_file->private_data;
  	err = perf_event_set_bpf_prog(event, prog, attr->link_create.perf_event.bpf_cookie);
  	if (err) {
  		bpf_link_cleanup(&link_primer);
  		goto out_put_file;
  	}
  	/* perf_event_set_bpf_prog() doesn't take its own refcnt on prog */
  	bpf_prog_inc(prog);
  
  	return bpf_link_settle(&link_primer);
  
  out_put_file:
  	fput(perf_file);
  	return err;
  }
  #else
  static int bpf_perf_link_attach(const union bpf_attr *attr, struct bpf_prog *prog)
  {
  	return -EOPNOTSUPP;
  }
  #endif /* CONFIG_PERF_EVENTS */
  
  #define BPF_RAW_TRACEPOINT_OPEN_LAST_FIELD raw_tracepoint.prog_fd
  
  static int bpf_raw_tracepoint_open(const union bpf_attr *attr)
  {
  	struct bpf_link_primer link_primer;
  	struct bpf_raw_tp_link *link;
  	struct bpf_raw_event_map *btp;
  	struct bpf_prog *prog;
  	const char *tp_name;
  	char buf[128];
  	int err;
  
  	if (CHECK_ATTR(BPF_RAW_TRACEPOINT_OPEN))
  		return -EINVAL;
  
  	prog = bpf_prog_get(attr->raw_tracepoint.prog_fd);
  	if (IS_ERR(prog))
  		return PTR_ERR(prog);
  
  	switch (prog->type) {
  	case BPF_PROG_TYPE_TRACING:
  	case BPF_PROG_TYPE_EXT:
  	case BPF_PROG_TYPE_LSM:
  		if (attr->raw_tracepoint.name) {
  			/* The attach point for this category of programs
  			 * should be specified via btf_id during program load.
  			 */
  			err = -EINVAL;
  			goto out_put_prog;
  		}
  		if (prog->type == BPF_PROG_TYPE_TRACING &&
  		    prog->expected_attach_type == BPF_TRACE_RAW_TP) {
  			tp_name = prog->aux->attach_func_name;
  			break;
  		}
  		err = bpf_tracing_prog_attach(prog, 0, 0);
  		if (err >= 0)
  			return err;
  		goto out_put_prog;
  	case BPF_PROG_TYPE_RAW_TRACEPOINT:
  	case BPF_PROG_TYPE_RAW_TRACEPOINT_WRITABLE:
  		if (strncpy_from_user(buf,
  				      u64_to_user_ptr(attr->raw_tracepoint.name),
  				      sizeof(buf) - 1) < 0) {
  			err = -EFAULT;
  			goto out_put_prog;
  		}
  		buf[sizeof(buf) - 1] = 0;
  		tp_name = buf;
  		break;
  	default:
  		err = -EINVAL;
  		goto out_put_prog;
  	}
  
  	btp = bpf_get_raw_tracepoint(tp_name);
  	if (!btp) {
  		err = -ENOENT;
  		goto out_put_prog;
  	}
  
  	link = kzalloc(sizeof(*link), GFP_USER);
  	if (!link) {
  		err = -ENOMEM;
  		goto out_put_btp;
  	}
  	bpf_link_init(&link->link, BPF_LINK_TYPE_RAW_TRACEPOINT,
  		      &bpf_raw_tp_link_lops, prog);
  	link->btp = btp;
  
  	err = bpf_link_prime(&link->link, &link_primer);
  	if (err) {
  		kfree(link);
  		goto out_put_btp;
  	}
  
  	err = bpf_probe_register(link->btp, prog);
  	if (err) {
  		bpf_link_cleanup(&link_primer);
  		goto out_put_btp;
  	}
  
  	return bpf_link_settle(&link_primer);
  
  out_put_btp:
  	bpf_put_raw_tracepoint(btp);
  out_put_prog:
  	bpf_prog_put(prog);
  	return err;
  }
  
  static int bpf_prog_attach_check_attach_type(const struct bpf_prog *prog,
  					     enum bpf_attach_type attach_type)
  {
  	switch (prog->type) {
  	case BPF_PROG_TYPE_CGROUP_SOCK:
  	case BPF_PROG_TYPE_CGROUP_SOCK_ADDR:
  	case BPF_PROG_TYPE_CGROUP_SOCKOPT:
  	case BPF_PROG_TYPE_SK_LOOKUP:
  		return attach_type == prog->expected_attach_type ? 0 : -EINVAL;
  	case BPF_PROG_TYPE_CGROUP_SKB:
  		if (!capable(CAP_NET_ADMIN))
  			/* cg-skb progs can be loaded by unpriv user.
  			 * check permissions at attach time.
  			 */
  			return -EPERM;
  		return prog->enforce_expected_attach_type &&
  			prog->expected_attach_type != attach_type ?
  			-EINVAL : 0;
  	default:
  		return 0;
  	}
  }
  
  static enum bpf_prog_type
  attach_type_to_prog_type(enum bpf_attach_type attach_type)
  {
  	switch (attach_type) {
  	case BPF_CGROUP_INET_INGRESS:
  	case BPF_CGROUP_INET_EGRESS:
  		return BPF_PROG_TYPE_CGROUP_SKB;
  	case BPF_CGROUP_INET_SOCK_CREATE:
  	case BPF_CGROUP_INET_SOCK_RELEASE:
  	case BPF_CGROUP_INET4_POST_BIND:
  	case BPF_CGROUP_INET6_POST_BIND:
  		return BPF_PROG_TYPE_CGROUP_SOCK;
  	case BPF_CGROUP_INET4_BIND:
  	case BPF_CGROUP_INET6_BIND:
  	case BPF_CGROUP_INET4_CONNECT:
  	case BPF_CGROUP_INET6_CONNECT:
  	case BPF_CGROUP_INET4_GETPEERNAME:
  	case BPF_CGROUP_INET6_GETPEERNAME:
  	case BPF_CGROUP_INET4_GETSOCKNAME:
  	case BPF_CGROUP_INET6_GETSOCKNAME:
  	case BPF_CGROUP_UDP4_SENDMSG:
  	case BPF_CGROUP_UDP6_SENDMSG:
  	case BPF_CGROUP_UDP4_RECVMSG:
  	case BPF_CGROUP_UDP6_RECVMSG:
  		return BPF_PROG_TYPE_CGROUP_SOCK_ADDR;
  	case BPF_CGROUP_SOCK_OPS:
  		return BPF_PROG_TYPE_SOCK_OPS;
  	case BPF_CGROUP_DEVICE:
  		return BPF_PROG_TYPE_CGROUP_DEVICE;
  	case BPF_SK_MSG_VERDICT:
  		return BPF_PROG_TYPE_SK_MSG;
  	case BPF_SK_SKB_STREAM_PARSER:
  	case BPF_SK_SKB_STREAM_VERDICT:
  	case BPF_SK_SKB_VERDICT:
  		return BPF_PROG_TYPE_SK_SKB;
  	case BPF_LIRC_MODE2:
  		return BPF_PROG_TYPE_LIRC_MODE2;
  	case BPF_FLOW_DISSECTOR:
  		return BPF_PROG_TYPE_FLOW_DISSECTOR;
  	case BPF_CGROUP_SYSCTL:
  		return BPF_PROG_TYPE_CGROUP_SYSCTL;
  	case BPF_CGROUP_GETSOCKOPT:
  	case BPF_CGROUP_SETSOCKOPT:
  		return BPF_PROG_TYPE_CGROUP_SOCKOPT;
  	case BPF_TRACE_ITER:
  		return BPF_PROG_TYPE_TRACING;
  	case BPF_SK_LOOKUP:
  		return BPF_PROG_TYPE_SK_LOOKUP;
  	case BPF_XDP:
  		return BPF_PROG_TYPE_XDP;
  	default:
  		return BPF_PROG_TYPE_UNSPEC;
  	}
  }
  
  #define BPF_PROG_ATTACH_LAST_FIELD replace_bpf_fd
  
  #define BPF_F_ATTACH_MASK \
  	(BPF_F_ALLOW_OVERRIDE | BPF_F_ALLOW_MULTI | BPF_F_REPLACE)
  
  static int bpf_prog_attach(const union bpf_attr *attr)
  {
  	enum bpf_prog_type ptype;
  	struct bpf_prog *prog;
  	int ret;
  
  	if (CHECK_ATTR(BPF_PROG_ATTACH))
  		return -EINVAL;
  
  	if (attr->attach_flags & ~BPF_F_ATTACH_MASK)
  		return -EINVAL;
  
  	ptype = attach_type_to_prog_type(attr->attach_type);
  	if (ptype == BPF_PROG_TYPE_UNSPEC)
  		return -EINVAL;
  
  	prog = bpf_prog_get_type(attr->attach_bpf_fd, ptype);
  	if (IS_ERR(prog))
  		return PTR_ERR(prog);
  
  	if (bpf_prog_attach_check_attach_type(prog, attr->attach_type)) {
  		bpf_prog_put(prog);
  		return -EINVAL;
  	}
  
  	switch (ptype) {
  	case BPF_PROG_TYPE_SK_SKB:
  	case BPF_PROG_TYPE_SK_MSG:
  		ret = sock_map_get_from_fd(attr, prog);
  		break;
  	case BPF_PROG_TYPE_LIRC_MODE2:
  		ret = lirc_prog_attach(attr, prog);
  		break;
  	case BPF_PROG_TYPE_FLOW_DISSECTOR:
  		ret = netns_bpf_prog_attach(attr, prog);
  		break;
  	case BPF_PROG_TYPE_CGROUP_DEVICE:
  	case BPF_PROG_TYPE_CGROUP_SKB:
  	case BPF_PROG_TYPE_CGROUP_SOCK:
  	case BPF_PROG_TYPE_CGROUP_SOCK_ADDR:
  	case BPF_PROG_TYPE_CGROUP_SOCKOPT:
  	case BPF_PROG_TYPE_CGROUP_SYSCTL:
  	case BPF_PROG_TYPE_SOCK_OPS:
  		ret = cgroup_bpf_prog_attach(attr, ptype, prog);
  		break;
  	default:
  		ret = -EINVAL;
  	}
  
  	if (ret)
  		bpf_prog_put(prog);
  	return ret;
  }
  
  #define BPF_PROG_DETACH_LAST_FIELD attach_type
  
  static int bpf_prog_detach(const union bpf_attr *attr)
  {
  	enum bpf_prog_type ptype;
  
  	if (CHECK_ATTR(BPF_PROG_DETACH))
  		return -EINVAL;
  
  	ptype = attach_type_to_prog_type(attr->attach_type);
  
  	switch (ptype) {
  	case BPF_PROG_TYPE_SK_MSG:
  	case BPF_PROG_TYPE_SK_SKB:
  		return sock_map_prog_detach(attr, ptype);
  	case BPF_PROG_TYPE_LIRC_MODE2:
  		return lirc_prog_detach(attr);
  	case BPF_PROG_TYPE_FLOW_DISSECTOR:
  		return netns_bpf_prog_detach(attr, ptype);
  	case BPF_PROG_TYPE_CGROUP_DEVICE:
  	case BPF_PROG_TYPE_CGROUP_SKB:
  	case BPF_PROG_TYPE_CGROUP_SOCK:
  	case BPF_PROG_TYPE_CGROUP_SOCK_ADDR:
  	case BPF_PROG_TYPE_CGROUP_SOCKOPT:
  	case BPF_PROG_TYPE_CGROUP_SYSCTL:
  	case BPF_PROG_TYPE_SOCK_OPS:
  		return cgroup_bpf_prog_detach(attr, ptype);
  	default:
  		return -EINVAL;
  	}
  }
  
  #define BPF_PROG_QUERY_LAST_FIELD query.prog_cnt
  
  static int bpf_prog_query(const union bpf_attr *attr,
  			  union bpf_attr __user *uattr)
  {
  	if (!capable(CAP_NET_ADMIN))
  		return -EPERM;
  	if (CHECK_ATTR(BPF_PROG_QUERY))
  		return -EINVAL;
  	if (attr->query.query_flags & ~BPF_F_QUERY_EFFECTIVE)
  		return -EINVAL;
  
  	switch (attr->query.attach_type) {
  	case BPF_CGROUP_INET_INGRESS:
  	case BPF_CGROUP_INET_EGRESS:
  	case BPF_CGROUP_INET_SOCK_CREATE:
  	case BPF_CGROUP_INET_SOCK_RELEASE:
  	case BPF_CGROUP_INET4_BIND:
  	case BPF_CGROUP_INET6_BIND:
  	case BPF_CGROUP_INET4_POST_BIND:
  	case BPF_CGROUP_INET6_POST_BIND:
  	case BPF_CGROUP_INET4_CONNECT:
  	case BPF_CGROUP_INET6_CONNECT:
  	case BPF_CGROUP_INET4_GETPEERNAME:
  	case BPF_CGROUP_INET6_GETPEERNAME:
  	case BPF_CGROUP_INET4_GETSOCKNAME:
  	case BPF_CGROUP_INET6_GETSOCKNAME:
  	case BPF_CGROUP_UDP4_SENDMSG:
  	case BPF_CGROUP_UDP6_SENDMSG:
  	case BPF_CGROUP_UDP4_RECVMSG:
  	case BPF_CGROUP_UDP6_RECVMSG:
  	case BPF_CGROUP_SOCK_OPS:
  	case BPF_CGROUP_DEVICE:
  	case BPF_CGROUP_SYSCTL:
  	case BPF_CGROUP_GETSOCKOPT:
  	case BPF_CGROUP_SETSOCKOPT:
  		return cgroup_bpf_prog_query(attr, uattr);
  	case BPF_LIRC_MODE2:
  		return lirc_prog_query(attr, uattr);
  	case BPF_FLOW_DISSECTOR:
  	case BPF_SK_LOOKUP:
  		return netns_bpf_prog_query(attr, uattr);
  	case BPF_SK_SKB_STREAM_PARSER:
  	case BPF_SK_SKB_STREAM_VERDICT:
  	case BPF_SK_MSG_VERDICT:
  	case BPF_SK_SKB_VERDICT:
  		return sock_map_bpf_prog_query(attr, uattr);
  	default:
  		return -EINVAL;
  	}
  }
  
  #define BPF_PROG_TEST_RUN_LAST_FIELD test.batch_size
  
  static int bpf_prog_test_run(const union bpf_attr *attr,
  			     union bpf_attr __user *uattr)
  {
  	struct bpf_prog *prog;
  	int ret = -ENOTSUPP;
  
  	if (CHECK_ATTR(BPF_PROG_TEST_RUN))
  		return -EINVAL;
  
  	if ((attr->test.ctx_size_in && !attr->test.ctx_in) ||
  	    (!attr->test.ctx_size_in && attr->test.ctx_in))
  		return -EINVAL;
  
  	if ((attr->test.ctx_size_out && !attr->test.ctx_out) ||
  	    (!attr->test.ctx_size_out && attr->test.ctx_out))
  		return -EINVAL;
  
  	prog = bpf_prog_get(attr->test.prog_fd);
  	if (IS_ERR(prog))
  		return PTR_ERR(prog);
  
  	if (prog->aux->ops->test_run)
  		ret = prog->aux->ops->test_run(prog, attr, uattr);
  
  	bpf_prog_put(prog);
  	return ret;
  }
  
  #define BPF_OBJ_GET_NEXT_ID_LAST_FIELD next_id
  
  static int bpf_obj_get_next_id(const union bpf_attr *attr,
  			       union bpf_attr __user *uattr,
  			       struct idr *idr,
  			       spinlock_t *lock)
  {
  	u32 next_id = attr->start_id;
  	int err = 0;
  
  	if (CHECK_ATTR(BPF_OBJ_GET_NEXT_ID) || next_id >= INT_MAX)
  		return -EINVAL;
  
  	if (!capable(CAP_SYS_ADMIN))
  		return -EPERM;
  
  	next_id++;
  	spin_lock_bh(lock);
  	if (!idr_get_next(idr, &next_id))
  		err = -ENOENT;
  	spin_unlock_bh(lock);
  
  	if (!err)
  		err = put_user(next_id, &uattr->next_id);
  
  	return err;
  }
  
  struct bpf_map *bpf_map_get_curr_or_next(u32 *id)
  {
  	struct bpf_map *map;
  
  	spin_lock_bh(&map_idr_lock);
  again:
  	map = idr_get_next(&map_idr, id);
  	if (map) {
  		map = __bpf_map_inc_not_zero(map, false);
  		if (IS_ERR(map)) {
  			(*id)++;
  			goto again;
  		}
  	}
  	spin_unlock_bh(&map_idr_lock);
  
  	return map;
  }
  
  struct bpf_prog *bpf_prog_get_curr_or_next(u32 *id)
  {
  	struct bpf_prog *prog;
  
  	spin_lock_bh(&prog_idr_lock);
  again:
  	prog = idr_get_next(&prog_idr, id);
  	if (prog) {
  		prog = bpf_prog_inc_not_zero(prog);
  		if (IS_ERR(prog)) {
  			(*id)++;
  			goto again;
  		}
  	}
  	spin_unlock_bh(&prog_idr_lock);
  
  	return prog;
  }
  
  #define BPF_PROG_GET_FD_BY_ID_LAST_FIELD prog_id
  
  struct bpf_prog *bpf_prog_by_id(u32 id)
  {
  	struct bpf_prog *prog;
  
  	if (!id)
  		return ERR_PTR(-ENOENT);
  
  	spin_lock_bh(&prog_idr_lock);
  	prog = idr_find(&prog_idr, id);
  	if (prog)
  		prog = bpf_prog_inc_not_zero(prog);
  	else
  		prog = ERR_PTR(-ENOENT);
  	spin_unlock_bh(&prog_idr_lock);
  	return prog;
  }
  
  static int bpf_prog_get_fd_by_id(const union bpf_attr *attr)
  {
  	struct bpf_prog *prog;
  	u32 id = attr->prog_id;
  	int fd;
  
  	if (CHECK_ATTR(BPF_PROG_GET_FD_BY_ID))
  		return -EINVAL;
  
  	if (!capable(CAP_SYS_ADMIN))
  		return -EPERM;
  
  	prog = bpf_prog_by_id(id);
  	if (IS_ERR(prog))
  		return PTR_ERR(prog);
  
  	fd = bpf_prog_new_fd(prog);
  	if (fd < 0)
  		bpf_prog_put(prog);
  
  	return fd;
  }
  
  #define BPF_MAP_GET_FD_BY_ID_LAST_FIELD open_flags
  
  static int bpf_map_get_fd_by_id(const union bpf_attr *attr)
  {
  	struct bpf_map *map;
  	u32 id = attr->map_id;
  	int f_flags;
  	int fd;
  
  	if (CHECK_ATTR(BPF_MAP_GET_FD_BY_ID) ||
  	    attr->open_flags & ~BPF_OBJ_FLAG_MASK)
  		return -EINVAL;
  
  	if (!capable(CAP_SYS_ADMIN))
  		return -EPERM;
  
  	f_flags = bpf_get_file_flag(attr->open_flags);
  	if (f_flags < 0)
  		return f_flags;
  
  	spin_lock_bh(&map_idr_lock);
  	map = idr_find(&map_idr, id);
  	if (map)
  		map = __bpf_map_inc_not_zero(map, true);
  	else
  		map = ERR_PTR(-ENOENT);
  	spin_unlock_bh(&map_idr_lock);
  
  	if (IS_ERR(map))
  		return PTR_ERR(map);
  
  	fd = bpf_map_new_fd(map, f_flags);
  	if (fd < 0)
  		bpf_map_put_with_uref(map);
  
  	return fd;
  }
  
  static const struct bpf_map *bpf_map_from_imm(const struct bpf_prog *prog,
  					      unsigned long addr, u32 *off,
  					      u32 *type)
  {
  	const struct bpf_map *map;
  	int i;
  
  	mutex_lock(&prog->aux->used_maps_mutex);
  	for (i = 0, *off = 0; i < prog->aux->used_map_cnt; i++) {
  		map = prog->aux->used_maps[i];
  		if (map == (void *)addr) {
  			*type = BPF_PSEUDO_MAP_FD;
  			goto out;
  		}
  		if (!map->ops->map_direct_value_meta)
  			continue;
  		if (!map->ops->map_direct_value_meta(map, addr, off)) {
  			*type = BPF_PSEUDO_MAP_VALUE;
  			goto out;
  		}
  	}
  	map = NULL;
  
  out:
  	mutex_unlock(&prog->aux->used_maps_mutex);
  	return map;
  }
  
  static struct bpf_insn *bpf_insn_prepare_dump(const struct bpf_prog *prog,
  					      const struct cred *f_cred)
  {
  	const struct bpf_map *map;
  	struct bpf_insn *insns;
  	u32 off, type;
  	u64 imm;
  	u8 code;
  	int i;
  
  	insns = kmemdup(prog->insnsi, bpf_prog_insn_size(prog),
  			GFP_USER);
  	if (!insns)
  		return insns;
  
  	for (i = 0; i < prog->len; i++) {
  		code = insns[i].code;
  
  		if (code == (BPF_JMP | BPF_TAIL_CALL)) {
  			insns[i].code = BPF_JMP | BPF_CALL;
  			insns[i].imm = BPF_FUNC_tail_call;
  			/* fall-through */
  		}
  		if (code == (BPF_JMP | BPF_CALL) ||
  		    code == (BPF_JMP | BPF_CALL_ARGS)) {
  			if (code == (BPF_JMP | BPF_CALL_ARGS))
  				insns[i].code = BPF_JMP | BPF_CALL;
  			if (!bpf_dump_raw_ok(f_cred))
  				insns[i].imm = 0;
  			continue;
  		}
  		if (BPF_CLASS(code) == BPF_LDX && BPF_MODE(code) == BPF_PROBE_MEM) {
  			insns[i].code = BPF_LDX | BPF_SIZE(code) | BPF_MEM;
  			continue;
  		}
  
  		if (code != (BPF_LD | BPF_IMM | BPF_DW))
  			continue;
  
  		imm = ((u64)insns[i + 1].imm << 32) | (u32)insns[i].imm;
  		map = bpf_map_from_imm(prog, imm, &off, &type);
  		if (map) {
  			insns[i].src_reg = type;
  			insns[i].imm = map->id;
  			insns[i + 1].imm = off;
  			continue;
  		}
  	}
  
  	return insns;
  }
  
  static int set_info_rec_size(struct bpf_prog_info *info)
  {
  	/*
  	 * Ensure info.*_rec_size is the same as kernel expected size
  	 *
  	 * or
  	 *
  	 * Only allow zero *_rec_size if both _rec_size and _cnt are
  	 * zero.  In this case, the kernel will set the expected
  	 * _rec_size back to the info.
  	 */
  
  	if ((info->nr_func_info || info->func_info_rec_size) &&
  	    info->func_info_rec_size != sizeof(struct bpf_func_info))
  		return -EINVAL;
  
  	if ((info->nr_line_info || info->line_info_rec_size) &&
  	    info->line_info_rec_size != sizeof(struct bpf_line_info))
  		return -EINVAL;
  
  	if ((info->nr_jited_line_info || info->jited_line_info_rec_size) &&
  	    info->jited_line_info_rec_size != sizeof(__u64))
  		return -EINVAL;
  
  	info->func_info_rec_size = sizeof(struct bpf_func_info);
  	info->line_info_rec_size = sizeof(struct bpf_line_info);
  	info->jited_line_info_rec_size = sizeof(__u64);
  
  	return 0;
  }
  
  static int bpf_prog_get_info_by_fd(struct file *file,
  				   struct bpf_prog *prog,
  				   const union bpf_attr *attr,
  				   union bpf_attr __user *uattr)
  {
  	struct bpf_prog_info __user *uinfo = u64_to_user_ptr(attr->info.info);
  	struct bpf_prog_info info;
  	u32 info_len = attr->info.info_len;
  	struct bpf_prog_kstats stats;
  	char __user *uinsns;
  	u32 ulen;
  	int err;
  
  	err = bpf_check_uarg_tail_zero(USER_BPFPTR(uinfo), sizeof(info), info_len);
  	if (err)
  		return err;
  	info_len = min_t(u32, sizeof(info), info_len);
  
  	memset(&info, 0, sizeof(info));
  	if (copy_from_user(&info, uinfo, info_len))
  		return -EFAULT;
  
  	info.type = prog->type;
  	info.id = prog->aux->id;
  	info.load_time = prog->aux->load_time;
  	info.created_by_uid = from_kuid_munged(current_user_ns(),
  					       prog->aux->user->uid);
  	info.gpl_compatible = prog->gpl_compatible;
  
  	memcpy(info.tag, prog->tag, sizeof(prog->tag));
  	memcpy(info.name, prog->aux->name, sizeof(prog->aux->name));
  
  	mutex_lock(&prog->aux->used_maps_mutex);
  	ulen = info.nr_map_ids;
  	info.nr_map_ids = prog->aux->used_map_cnt;
  	ulen = min_t(u32, info.nr_map_ids, ulen);
  	if (ulen) {
  		u32 __user *user_map_ids = u64_to_user_ptr(info.map_ids);
  		u32 i;
  
  		for (i = 0; i < ulen; i++)
  			if (put_user(prog->aux->used_maps[i]->id,
  				     &user_map_ids[i])) {
  				mutex_unlock(&prog->aux->used_maps_mutex);
  				return -EFAULT;
  			}
  	}
  	mutex_unlock(&prog->aux->used_maps_mutex);
  
  	err = set_info_rec_size(&info);
  	if (err)
  		return err;
  
  	bpf_prog_get_stats(prog, &stats);
  	info.run_time_ns = stats.nsecs;
  	info.run_cnt = stats.cnt;
  	info.recursion_misses = stats.misses;
  
  	info.verified_insns = prog->aux->verified_insns;
  
  	if (!bpf_capable()) {
  		info.jited_prog_len = 0;
  		info.xlated_prog_len = 0;
  		info.nr_jited_ksyms = 0;
  		info.nr_jited_func_lens = 0;
  		info.nr_func_info = 0;
  		info.nr_line_info = 0;
  		info.nr_jited_line_info = 0;
  		goto done;
  	}
  
  	ulen = info.xlated_prog_len;
  	info.xlated_prog_len = bpf_prog_insn_size(prog);
  	if (info.xlated_prog_len && ulen) {
  		struct bpf_insn *insns_sanitized;
  		bool fault;
  
  		if (prog->blinded && !bpf_dump_raw_ok(file->f_cred)) {
  			info.xlated_prog_insns = 0;
  			goto done;
  		}
  		insns_sanitized = bpf_insn_prepare_dump(prog, file->f_cred);
  		if (!insns_sanitized)
  			return -ENOMEM;
  		uinsns = u64_to_user_ptr(info.xlated_prog_insns);
  		ulen = min_t(u32, info.xlated_prog_len, ulen);
  		fault = copy_to_user(uinsns, insns_sanitized, ulen);
  		kfree(insns_sanitized);
  		if (fault)
  			return -EFAULT;
  	}
  
  	if (bpf_prog_is_dev_bound(prog->aux)) {
  		err = bpf_prog_offload_info_fill(&info, prog);
  		if (err)
  			return err;
  		goto done;
  	}
  
  	/* NOTE: the following code is supposed to be skipped for offload.
  	 * bpf_prog_offload_info_fill() is the place to fill similar fields
  	 * for offload.
  	 */
  	ulen = info.jited_prog_len;
  	if (prog->aux->func_cnt) {
  		u32 i;
  
  		info.jited_prog_len = 0;
  		for (i = 0; i < prog->aux->func_cnt; i++)
  			info.jited_prog_len += prog->aux->func[i]->jited_len;
  	} else {
  		info.jited_prog_len = prog->jited_len;
  	}
  
  	if (info.jited_prog_len && ulen) {
  		if (bpf_dump_raw_ok(file->f_cred)) {
  			uinsns = u64_to_user_ptr(info.jited_prog_insns);
  			ulen = min_t(u32, info.jited_prog_len, ulen);
  
  			/* for multi-function programs, copy the JITed
  			 * instructions for all the functions
  			 */
  			if (prog->aux->func_cnt) {
  				u32 len, free, i;
  				u8 *img;
  
  				free = ulen;
  				for (i = 0; i < prog->aux->func_cnt; i++) {
  					len = prog->aux->func[i]->jited_len;
  					len = min_t(u32, len, free);
  					img = (u8 *) prog->aux->func[i]->bpf_func;
  					if (copy_to_user(uinsns, img, len))
  						return -EFAULT;
  					uinsns += len;
  					free -= len;
  					if (!free)
  						break;
  				}
  			} else {
  				if (copy_to_user(uinsns, prog->bpf_func, ulen))
  					return -EFAULT;
  			}
  		} else {
  			info.jited_prog_insns = 0;
  		}
  	}
  
  	ulen = info.nr_jited_ksyms;
  	info.nr_jited_ksyms = prog->aux->func_cnt ? : 1;
  	if (ulen) {
  		if (bpf_dump_raw_ok(file->f_cred)) {
  			unsigned long ksym_addr;
  			u64 __user *user_ksyms;
  			u32 i;
  
  			/* copy the address of the kernel symbol
  			 * corresponding to each function
  			 */
  			ulen = min_t(u32, info.nr_jited_ksyms, ulen);
  			user_ksyms = u64_to_user_ptr(info.jited_ksyms);
  			if (prog->aux->func_cnt) {
  				for (i = 0; i < ulen; i++) {
  					ksym_addr = (unsigned long)
  						prog->aux->func[i]->bpf_func;
  					if (put_user((u64) ksym_addr,
  						     &user_ksyms[i]))
  						return -EFAULT;
  				}
  			} else {
  				ksym_addr = (unsigned long) prog->bpf_func;
  				if (put_user((u64) ksym_addr, &user_ksyms[0]))
  					return -EFAULT;
  			}
  		} else {
  			info.jited_ksyms = 0;
  		}
  	}
  
  	ulen = info.nr_jited_func_lens;
  	info.nr_jited_func_lens = prog->aux->func_cnt ? : 1;
  	if (ulen) {
  		if (bpf_dump_raw_ok(file->f_cred)) {
  			u32 __user *user_lens;
  			u32 func_len, i;
  
  			/* copy the JITed image lengths for each function */
  			ulen = min_t(u32, info.nr_jited_func_lens, ulen);
  			user_lens = u64_to_user_ptr(info.jited_func_lens);
  			if (prog->aux->func_cnt) {
  				for (i = 0; i < ulen; i++) {
  					func_len =
  						prog->aux->func[i]->jited_len;
  					if (put_user(func_len, &user_lens[i]))
  						return -EFAULT;
  				}
  			} else {
  				func_len = prog->jited_len;
  				if (put_user(func_len, &user_lens[0]))
  					return -EFAULT;
  			}
  		} else {
  			info.jited_func_lens = 0;
  		}
  	}
  
  	if (prog->aux->btf)
  		info.btf_id = btf_obj_id(prog->aux->btf);
  
  	ulen = info.nr_func_info;
  	info.nr_func_info = prog->aux->func_info_cnt;
  	if (info.nr_func_info && ulen) {
  		char __user *user_finfo;
  
  		user_finfo = u64_to_user_ptr(info.func_info);
  		ulen = min_t(u32, info.nr_func_info, ulen);
  		if (copy_to_user(user_finfo, prog->aux->func_info,
  				 info.func_info_rec_size * ulen))
  			return -EFAULT;
  	}
  
  	ulen = info.nr_line_info;
  	info.nr_line_info = prog->aux->nr_linfo;
  	if (info.nr_line_info && ulen) {
  		__u8 __user *user_linfo;
  
  		user_linfo = u64_to_user_ptr(info.line_info);
  		ulen = min_t(u32, info.nr_line_info, ulen);
  		if (copy_to_user(user_linfo, prog->aux->linfo,
  				 info.line_info_rec_size * ulen))
  			return -EFAULT;
  	}
  
  	ulen = info.nr_jited_line_info;
  	if (prog->aux->jited_linfo)
  		info.nr_jited_line_info = prog->aux->nr_linfo;
  	else
  		info.nr_jited_line_info = 0;
  	if (info.nr_jited_line_info && ulen) {
  		if (bpf_dump_raw_ok(file->f_cred)) {
  			__u64 __user *user_linfo;
  			u32 i;
  
  			user_linfo = u64_to_user_ptr(info.jited_line_info);
  			ulen = min_t(u32, info.nr_jited_line_info, ulen);
  			for (i = 0; i < ulen; i++) {
  				if (put_user((__u64)(long)prog->aux->jited_linfo[i],
  					     &user_linfo[i]))
  					return -EFAULT;
  			}
  		} else {
  			info.jited_line_info = 0;
  		}
  	}
  
  	ulen = info.nr_prog_tags;
  	info.nr_prog_tags = prog->aux->func_cnt ? : 1;
  	if (ulen) {
  		__u8 __user (*user_prog_tags)[BPF_TAG_SIZE];
  		u32 i;
  
  		user_prog_tags = u64_to_user_ptr(info.prog_tags);
  		ulen = min_t(u32, info.nr_prog_tags, ulen);
  		if (prog->aux->func_cnt) {
  			for (i = 0; i < ulen; i++) {
  				if (copy_to_user(user_prog_tags[i],
  						 prog->aux->func[i]->tag,
  						 BPF_TAG_SIZE))
  					return -EFAULT;
  			}
  		} else {
  			if (copy_to_user(user_prog_tags[0],
  					 prog->tag, BPF_TAG_SIZE))
  				return -EFAULT;
  		}
  	}
  
  done:
  	if (copy_to_user(uinfo, &info, info_len) ||
  	    put_user(info_len, &uattr->info.info_len))
  		return -EFAULT;
  
  	return 0;
  }
  
  static int bpf_map_get_info_by_fd(struct file *file,
  				  struct bpf_map *map,
  				  const union bpf_attr *attr,
  				  union bpf_attr __user *uattr)
  {
  	struct bpf_map_info __user *uinfo = u64_to_user_ptr(attr->info.info);
  	struct bpf_map_info info;
  	u32 info_len = attr->info.info_len;
  	int err;
  
  	err = bpf_check_uarg_tail_zero(USER_BPFPTR(uinfo), sizeof(info), info_len);
  	if (err)
  		return err;
  	info_len = min_t(u32, sizeof(info), info_len);
  
  	memset(&info, 0, sizeof(info));
  	info.type = map->map_type;
  	info.id = map->id;
  	info.key_size = map->key_size;
  	info.value_size = map->value_size;
  	info.max_entries = map->max_entries;
  	info.map_flags = map->map_flags;
  	info.map_extra = map->map_extra;
  	memcpy(info.name, map->name, sizeof(map->name));
  
  	if (map->btf) {
  		info.btf_id = btf_obj_id(map->btf);
  		info.btf_key_type_id = map->btf_key_type_id;
  		info.btf_value_type_id = map->btf_value_type_id;
  	}
  	info.btf_vmlinux_value_type_id = map->btf_vmlinux_value_type_id;
  
  	if (bpf_map_is_dev_bound(map)) {
  		err = bpf_map_offload_info_fill(&info, map);
  		if (err)
  			return err;
  	}
  
  	if (copy_to_user(uinfo, &info, info_len) ||
  	    put_user(info_len, &uattr->info.info_len))
  		return -EFAULT;
  
  	return 0;
  }
  
  static int bpf_btf_get_info_by_fd(struct file *file,
  				  struct btf *btf,
  				  const union bpf_attr *attr,
  				  union bpf_attr __user *uattr)
  {
  	struct bpf_btf_info __user *uinfo = u64_to_user_ptr(attr->info.info);
  	u32 info_len = attr->info.info_len;
  	int err;
  
  	err = bpf_check_uarg_tail_zero(USER_BPFPTR(uinfo), sizeof(*uinfo), info_len);
  	if (err)
  		return err;
  
  	return btf_get_info_by_fd(btf, attr, uattr);
  }
  
  static int bpf_link_get_info_by_fd(struct file *file,
  				  struct bpf_link *link,
  				  const union bpf_attr *attr,
  				  union bpf_attr __user *uattr)
  {
  	struct bpf_link_info __user *uinfo = u64_to_user_ptr(attr->info.info);
  	struct bpf_link_info info;
  	u32 info_len = attr->info.info_len;
  	int err;
  
  	err = bpf_check_uarg_tail_zero(USER_BPFPTR(uinfo), sizeof(info), info_len);
  	if (err)
  		return err;
  	info_len = min_t(u32, sizeof(info), info_len);
  
  	memset(&info, 0, sizeof(info));
  	if (copy_from_user(&info, uinfo, info_len))
  		return -EFAULT;
  
  	info.type = link->type;
  	info.id = link->id;
  	info.prog_id = link->prog->aux->id;
  
  	if (link->ops->fill_link_info) {
  		err = link->ops->fill_link_info(link, &info);
  		if (err)
  			return err;
  	}
  
  	if (copy_to_user(uinfo, &info, info_len) ||
  	    put_user(info_len, &uattr->info.info_len))
  		return -EFAULT;
  
  	return 0;
  }
  
  
  #define BPF_OBJ_GET_INFO_BY_FD_LAST_FIELD info.info
  
  static int bpf_obj_get_info_by_fd(const union bpf_attr *attr,
  				  union bpf_attr __user *uattr)
  {
  	int ufd = attr->info.bpf_fd;
  	struct fd f;
  	int err;
  
  	if (CHECK_ATTR(BPF_OBJ_GET_INFO_BY_FD))
  		return -EINVAL;
  
  	f = fdget(ufd);
  	if (!f.file)
  		return -EBADFD;
  
  	if (f.file->f_op == &bpf_prog_fops)
  		err = bpf_prog_get_info_by_fd(f.file, f.file->private_data, attr,
  					      uattr);
  	else if (f.file->f_op == &bpf_map_fops)
  		err = bpf_map_get_info_by_fd(f.file, f.file->private_data, attr,
  					     uattr);
  	else if (f.file->f_op == &btf_fops)
  		err = bpf_btf_get_info_by_fd(f.file, f.file->private_data, attr, uattr);
  	else if (f.file->f_op == &bpf_link_fops)
  		err = bpf_link_get_info_by_fd(f.file, f.file->private_data,
  					      attr, uattr);
  	else
  		err = -EINVAL;
  
  	fdput(f);
  	return err;
  }
  
  #define BPF_BTF_LOAD_LAST_FIELD btf_log_level
  
  static int bpf_btf_load(const union bpf_attr *attr, bpfptr_t uattr)
  {
  	if (CHECK_ATTR(BPF_BTF_LOAD))
  		return -EINVAL;
  
  	if (!bpf_capable())
  		return -EPERM;
  
  	return btf_new_fd(attr, uattr);
  }
  
  #define BPF_BTF_GET_FD_BY_ID_LAST_FIELD btf_id
  
  static int bpf_btf_get_fd_by_id(const union bpf_attr *attr)
  {
  	if (CHECK_ATTR(BPF_BTF_GET_FD_BY_ID))
  		return -EINVAL;
  
  	if (!capable(CAP_SYS_ADMIN))
  		return -EPERM;
  
  	return btf_get_fd_by_id(attr->btf_id);
  }
  
  static int bpf_task_fd_query_copy(const union bpf_attr *attr,
  				    union bpf_attr __user *uattr,
  				    u32 prog_id, u32 fd_type,
  				    const char *buf, u64 probe_offset,
  				    u64 probe_addr)
  {
  	char __user *ubuf = u64_to_user_ptr(attr->task_fd_query.buf);
  	u32 len = buf ? strlen(buf) : 0, input_len;
  	int err = 0;
  
  	if (put_user(len, &uattr->task_fd_query.buf_len))
  		return -EFAULT;
  	input_len = attr->task_fd_query.buf_len;
  	if (input_len && ubuf) {
  		if (!len) {
  			/* nothing to copy, just make ubuf NULL terminated */
  			char zero = '\0';
  
  			if (put_user(zero, ubuf))
  				return -EFAULT;
  		} else if (input_len >= len + 1) {
  			/* ubuf can hold the string with NULL terminator */
  			if (copy_to_user(ubuf, buf, len + 1))
  				return -EFAULT;
  		} else {
  			/* ubuf cannot hold the string with NULL terminator,
  			 * do a partial copy with NULL terminator.
  			 */
  			char zero = '\0';
  
  			err = -ENOSPC;
  			if (copy_to_user(ubuf, buf, input_len - 1))
  				return -EFAULT;
  			if (put_user(zero, ubuf + input_len - 1))
  				return -EFAULT;
  		}
  	}
  
  	if (put_user(prog_id, &uattr->task_fd_query.prog_id) ||
  	    put_user(fd_type, &uattr->task_fd_query.fd_type) ||
  	    put_user(probe_offset, &uattr->task_fd_query.probe_offset) ||
  	    put_user(probe_addr, &uattr->task_fd_query.probe_addr))
  		return -EFAULT;
  
  	return err;
  }
  
  #define BPF_TASK_FD_QUERY_LAST_FIELD task_fd_query.probe_addr
  
  static int bpf_task_fd_query(const union bpf_attr *attr,
  			     union bpf_attr __user *uattr)
  {
  	pid_t pid = attr->task_fd_query.pid;
  	u32 fd = attr->task_fd_query.fd;
  	const struct perf_event *event;
  	struct task_struct *task;
  	struct file *file;
  	int err;
  
  	if (CHECK_ATTR(BPF_TASK_FD_QUERY))
  		return -EINVAL;
  
  	if (!capable(CAP_SYS_ADMIN))
  		return -EPERM;
  
  	if (attr->task_fd_query.flags != 0)
  		return -EINVAL;
  
  	task = get_pid_task(find_vpid(pid), PIDTYPE_PID);
  	if (!task)
  		return -ENOENT;
  
  	err = 0;
  	file = fget_task(task, fd);
  	put_task_struct(task);
  	if (!file)
  		return -EBADF;
  
  	if (file->f_op == &bpf_link_fops) {
  		struct bpf_link *link = file->private_data;
  
  		if (link->ops == &bpf_raw_tp_link_lops) {
  			struct bpf_raw_tp_link *raw_tp =
  				container_of(link, struct bpf_raw_tp_link, link);
  			struct bpf_raw_event_map *btp = raw_tp->btp;
  
  			err = bpf_task_fd_query_copy(attr, uattr,
  						     raw_tp->link.prog->aux->id,
  						     BPF_FD_TYPE_RAW_TRACEPOINT,
  						     btp->tp->name, 0, 0);
  			goto put_file;
  		}
  		goto out_not_supp;
  	}
  
  	event = perf_get_event(file);
  	if (!IS_ERR(event)) {
  		u64 probe_offset, probe_addr;
  		u32 prog_id, fd_type;
  		const char *buf;
  
  		err = bpf_get_perf_event_info(event, &prog_id, &fd_type,
  					      &buf, &probe_offset,
  					      &probe_addr);
  		if (!err)
  			err = bpf_task_fd_query_copy(attr, uattr, prog_id,
  						     fd_type, buf,
  						     probe_offset,
  						     probe_addr);
  		goto put_file;
  	}
  
  out_not_supp:
  	err = -ENOTSUPP;
  put_file:
  	fput(file);
  	return err;
  }
  
  #define BPF_MAP_BATCH_LAST_FIELD batch.flags
  
  #define BPF_DO_BATCH(fn)			\
  	do {					\
  		if (!fn) {			\
  			err = -ENOTSUPP;	\
  			goto err_put;		\
  		}				\
  		err = fn(map, attr, uattr);	\
  	} while (0)
  
  static int bpf_map_do_batch(const union bpf_attr *attr,
  			    union bpf_attr __user *uattr,
  			    int cmd)
  {
  	bool has_read  = cmd == BPF_MAP_LOOKUP_BATCH ||
  			 cmd == BPF_MAP_LOOKUP_AND_DELETE_BATCH;
  	bool has_write = cmd != BPF_MAP_LOOKUP_BATCH;
  	struct bpf_map *map;
  	int err, ufd;
  	struct fd f;
  
  	if (CHECK_ATTR(BPF_MAP_BATCH))
  		return -EINVAL;
  
  	ufd = attr->batch.map_fd;
  	f = fdget(ufd);
  	map = __bpf_map_get(f);
  	if (IS_ERR(map))
  		return PTR_ERR(map);
  	if (has_write)
  		bpf_map_write_active_inc(map);
  	if (has_read && !(map_get_sys_perms(map, f) & FMODE_CAN_READ)) {
  		err = -EPERM;
  		goto err_put;
  	}
  	if (has_write && !(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) {
  		err = -EPERM;
  		goto err_put;
  	}
  
  	if (cmd == BPF_MAP_LOOKUP_BATCH)
  		BPF_DO_BATCH(map->ops->map_lookup_batch);
  	else if (cmd == BPF_MAP_LOOKUP_AND_DELETE_BATCH)
  		BPF_DO_BATCH(map->ops->map_lookup_and_delete_batch);
  	else if (cmd == BPF_MAP_UPDATE_BATCH)
  		BPF_DO_BATCH(map->ops->map_update_batch);
  	else
  		BPF_DO_BATCH(map->ops->map_delete_batch);
  err_put:
  	if (has_write)
  		bpf_map_write_active_dec(map);
  	fdput(f);
  	return err;
  }
  
  static int tracing_bpf_link_attach(const union bpf_attr *attr, bpfptr_t uattr,
  				   struct bpf_prog *prog)
  {
  	if (attr->link_create.attach_type != prog->expected_attach_type)
  		return -EINVAL;
  
  	if (prog->expected_attach_type == BPF_TRACE_ITER)
  		return bpf_iter_link_attach(attr, uattr, prog);
  	else if (prog->type == BPF_PROG_TYPE_EXT)
  		return bpf_tracing_prog_attach(prog,
  					       attr->link_create.target_fd,
  					       attr->link_create.target_btf_id);
  	return -EINVAL;
  }
  
  #define BPF_LINK_CREATE_LAST_FIELD link_create.kprobe_multi.cookies
  static int link_create(union bpf_attr *attr, bpfptr_t uattr)
  {
  	enum bpf_prog_type ptype;
  	struct bpf_prog *prog;
  	int ret;
  
  	if (CHECK_ATTR(BPF_LINK_CREATE))
  		return -EINVAL;
  
  	prog = bpf_prog_get(attr->link_create.prog_fd);
  	if (IS_ERR(prog))
  		return PTR_ERR(prog);
  
  	ret = bpf_prog_attach_check_attach_type(prog,
  						attr->link_create.attach_type);
  	if (ret)
  		goto out;
  
  	switch (prog->type) {
  	case BPF_PROG_TYPE_EXT:
  		ret = tracing_bpf_link_attach(attr, uattr, prog);
  		goto out;
  	case BPF_PROG_TYPE_PERF_EVENT:
  	case BPF_PROG_TYPE_TRACEPOINT:
  		if (attr->link_create.attach_type != BPF_PERF_EVENT) {
  			ret = -EINVAL;
  			goto out;
  		}
  		ptype = prog->type;
  		break;
  	case BPF_PROG_TYPE_KPROBE:
  		if (attr->link_create.attach_type != BPF_PERF_EVENT &&
  		    attr->link_create.attach_type != BPF_TRACE_KPROBE_MULTI) {
  			ret = -EINVAL;
  			goto out;
  		}
  		ptype = prog->type;
  		break;
  	default:
  		ptype = attach_type_to_prog_type(attr->link_create.attach_type);
  		if (ptype == BPF_PROG_TYPE_UNSPEC || ptype != prog->type) {
  			ret = -EINVAL;
  			goto out;
  		}
  		break;
  	}
  
  	switch (ptype) {
  	case BPF_PROG_TYPE_CGROUP_SKB:
  	case BPF_PROG_TYPE_CGROUP_SOCK:
  	case BPF_PROG_TYPE_CGROUP_SOCK_ADDR:
  	case BPF_PROG_TYPE_SOCK_OPS:
  	case BPF_PROG_TYPE_CGROUP_DEVICE:
  	case BPF_PROG_TYPE_CGROUP_SYSCTL:
  	case BPF_PROG_TYPE_CGROUP_SOCKOPT:
  		ret = cgroup_bpf_link_attach(attr, prog);
  		break;
  	case BPF_PROG_TYPE_TRACING:
  		ret = tracing_bpf_link_attach(attr, uattr, prog);
  		break;
  	case BPF_PROG_TYPE_FLOW_DISSECTOR:
  	case BPF_PROG_TYPE_SK_LOOKUP:
  		ret = netns_bpf_link_create(attr, prog);
  		break;
  #ifdef CONFIG_NET
  	case BPF_PROG_TYPE_XDP:
  		ret = bpf_xdp_link_attach(attr, prog);
  		break;
  #endif
  	case BPF_PROG_TYPE_PERF_EVENT:
  	case BPF_PROG_TYPE_TRACEPOINT:
  		ret = bpf_perf_link_attach(attr, prog);
  		break;
  	case BPF_PROG_TYPE_KPROBE:
  		if (attr->link_create.attach_type == BPF_PERF_EVENT)
  			ret = bpf_perf_link_attach(attr, prog);
  		else
  			ret = bpf_kprobe_multi_link_attach(attr, prog);
  		break;
  	default:
  		ret = -EINVAL;
  	}
  
  out:
  	if (ret < 0)
  		bpf_prog_put(prog);
  	return ret;
  }
  
  #define BPF_LINK_UPDATE_LAST_FIELD link_update.old_prog_fd
  
  static int link_update(union bpf_attr *attr)
  {
  	struct bpf_prog *old_prog = NULL, *new_prog;
  	struct bpf_link *link;
  	u32 flags;
  	int ret;
  
  	if (CHECK_ATTR(BPF_LINK_UPDATE))
  		return -EINVAL;
  
  	flags = attr->link_update.flags;
  	if (flags & ~BPF_F_REPLACE)
  		return -EINVAL;
  
  	link = bpf_link_get_from_fd(attr->link_update.link_fd);
  	if (IS_ERR(link))
  		return PTR_ERR(link);
  
  	new_prog = bpf_prog_get(attr->link_update.new_prog_fd);
  	if (IS_ERR(new_prog)) {
  		ret = PTR_ERR(new_prog);
  		goto out_put_link;
  	}
  
  	if (flags & BPF_F_REPLACE) {
  		old_prog = bpf_prog_get(attr->link_update.old_prog_fd);
  		if (IS_ERR(old_prog)) {
  			ret = PTR_ERR(old_prog);
  			old_prog = NULL;
  			goto out_put_progs;
  		}
  	} else if (attr->link_update.old_prog_fd) {
  		ret = -EINVAL;
  		goto out_put_progs;
  	}
  
  	if (link->ops->update_prog)
  		ret = link->ops->update_prog(link, new_prog, old_prog);
  	else
  		ret = -EINVAL;
  
  out_put_progs:
  	if (old_prog)
  		bpf_prog_put(old_prog);
  	if (ret)
  		bpf_prog_put(new_prog);
  out_put_link:
  	bpf_link_put(link);
  	return ret;
  }
  
  #define BPF_LINK_DETACH_LAST_FIELD link_detach.link_fd
  
  static int link_detach(union bpf_attr *attr)
  {
  	struct bpf_link *link;
  	int ret;
  
  	if (CHECK_ATTR(BPF_LINK_DETACH))
  		return -EINVAL;
  
  	link = bpf_link_get_from_fd(attr->link_detach.link_fd);
  	if (IS_ERR(link))
  		return PTR_ERR(link);
  
  	if (link->ops->detach)
  		ret = link->ops->detach(link);
  	else
  		ret = -EOPNOTSUPP;
  
  	bpf_link_put(link);
  	return ret;
  }
  
  static struct bpf_link *bpf_link_inc_not_zero(struct bpf_link *link)
  {
  	return atomic64_fetch_add_unless(&link->refcnt, 1, 0) ? link : ERR_PTR(-ENOENT);
  }
  
  struct bpf_link *bpf_link_by_id(u32 id)
  {
  	struct bpf_link *link;
  
  	if (!id)
  		return ERR_PTR(-ENOENT);
  
  	spin_lock_bh(&link_idr_lock);
  	/* before link is "settled", ID is 0, pretend it doesn't exist yet */
  	link = idr_find(&link_idr, id);
  	if (link) {
  		if (link->id)
  			link = bpf_link_inc_not_zero(link);
  		else
  			link = ERR_PTR(-EAGAIN);
  	} else {
  		link = ERR_PTR(-ENOENT);
  	}
  	spin_unlock_bh(&link_idr_lock);
  	return link;
  }
  
  #define BPF_LINK_GET_FD_BY_ID_LAST_FIELD link_id
  
  static int bpf_link_get_fd_by_id(const union bpf_attr *attr)
  {
  	struct bpf_link *link;
  	u32 id = attr->link_id;
  	int fd;
  
  	if (CHECK_ATTR(BPF_LINK_GET_FD_BY_ID))
  		return -EINVAL;
  
  	if (!capable(CAP_SYS_ADMIN))
  		return -EPERM;
  
  	link = bpf_link_by_id(id);
  	if (IS_ERR(link))
  		return PTR_ERR(link);
  
  	fd = bpf_link_new_fd(link);
  	if (fd < 0)
  		bpf_link_put(link);
  
  	return fd;
  }
  
  DEFINE_MUTEX(bpf_stats_enabled_mutex);
  
  static int bpf_stats_release(struct inode *inode, struct file *file)
  {
  	mutex_lock(&bpf_stats_enabled_mutex);
  	static_key_slow_dec(&bpf_stats_enabled_key.key);
  	mutex_unlock(&bpf_stats_enabled_mutex);
  	return 0;
  }
  
  static const struct file_operations bpf_stats_fops = {
  	.release = bpf_stats_release,
  };
  
  static int bpf_enable_runtime_stats(void)
  {
  	int fd;
  
  	mutex_lock(&bpf_stats_enabled_mutex);
  
  	/* Set a very high limit to avoid overflow */
  	if (static_key_count(&bpf_stats_enabled_key.key) > INT_MAX / 2) {
  		mutex_unlock(&bpf_stats_enabled_mutex);
  		return -EBUSY;
  	}
  
  	fd = anon_inode_getfd("bpf-stats", &bpf_stats_fops, NULL, O_CLOEXEC);
  	if (fd >= 0)
  		static_key_slow_inc(&bpf_stats_enabled_key.key);
  
  	mutex_unlock(&bpf_stats_enabled_mutex);
  	return fd;
  }
  
  #define BPF_ENABLE_STATS_LAST_FIELD enable_stats.type
  
  static int bpf_enable_stats(union bpf_attr *attr)
  {
  
  	if (CHECK_ATTR(BPF_ENABLE_STATS))
  		return -EINVAL;
  
  	if (!capable(CAP_SYS_ADMIN))
  		return -EPERM;
  
  	switch (attr->enable_stats.type) {
  	case BPF_STATS_RUN_TIME:
  		return bpf_enable_runtime_stats();
  	default:
  		break;
  	}
  	return -EINVAL;
  }
  
  #define BPF_ITER_CREATE_LAST_FIELD iter_create.flags
  
  static int bpf_iter_create(union bpf_attr *attr)
  {
  	struct bpf_link *link;
  	int err;
  
  	if (CHECK_ATTR(BPF_ITER_CREATE))
  		return -EINVAL;
  
  	if (attr->iter_create.flags)
  		return -EINVAL;
  
  	link = bpf_link_get_from_fd(attr->iter_create.link_fd);
  	if (IS_ERR(link))
  		return PTR_ERR(link);
  
  	err = bpf_iter_new_fd(link);
  	bpf_link_put(link);
  
  	return err;
  }
  
  #define BPF_PROG_BIND_MAP_LAST_FIELD prog_bind_map.flags
  
  static int bpf_prog_bind_map(union bpf_attr *attr)
  {
  	struct bpf_prog *prog;
  	struct bpf_map *map;
  	struct bpf_map **used_maps_old, **used_maps_new;
  	int i, ret = 0;
  
  	if (CHECK_ATTR(BPF_PROG_BIND_MAP))
  		return -EINVAL;
  
  	if (attr->prog_bind_map.flags)
  		return -EINVAL;
  
  	prog = bpf_prog_get(attr->prog_bind_map.prog_fd);
  	if (IS_ERR(prog))
  		return PTR_ERR(prog);
  
  	map = bpf_map_get(attr->prog_bind_map.map_fd);
  	if (IS_ERR(map)) {
  		ret = PTR_ERR(map);
  		goto out_prog_put;
  	}
  
  	mutex_lock(&prog->aux->used_maps_mutex);
  
  	used_maps_old = prog->aux->used_maps;
  
  	for (i = 0; i < prog->aux->used_map_cnt; i++)
  		if (used_maps_old[i] == map) {
  			bpf_map_put(map);
  			goto out_unlock;
  		}
  
  	used_maps_new = kmalloc_array(prog->aux->used_map_cnt + 1,
  				      sizeof(used_maps_new[0]),
  				      GFP_KERNEL);
  	if (!used_maps_new) {
  		ret = -ENOMEM;
  		goto out_unlock;
  	}
  
  	memcpy(used_maps_new, used_maps_old,
  	       sizeof(used_maps_old[0]) * prog->aux->used_map_cnt);
  	used_maps_new[prog->aux->used_map_cnt] = map;
  
  	prog->aux->used_map_cnt++;
  	prog->aux->used_maps = used_maps_new;
  
  	kfree(used_maps_old);
  
  out_unlock:
  	mutex_unlock(&prog->aux->used_maps_mutex);
  
  	if (ret)
  		bpf_map_put(map);
  out_prog_put:
  	bpf_prog_put(prog);
  	return ret;
  }
  
  static int __sys_bpf(int cmd, bpfptr_t uattr, unsigned int size)
  {
  	union bpf_attr attr;
  	int err;
  
  	if (sysctl_unprivileged_bpf_disabled && !bpf_capable())
  		return -EPERM;
  
  	err = bpf_check_uarg_tail_zero(uattr, sizeof(attr), size);
  	if (err)
  		return err;
  	size = min_t(u32, size, sizeof(attr));
  
  	/* copy attributes from user space, may be less than sizeof(bpf_attr) */
  	memset(&attr, 0, sizeof(attr));
  	if (copy_from_bpfptr(&attr, uattr, size) != 0)
  		return -EFAULT;
  
  	err = security_bpf(cmd, &attr, size);
  	if (err < 0)
  		return err;
  
  	switch (cmd) {
  	case BPF_MAP_CREATE:
  		err = map_create(&attr);
  		break;
  	case BPF_MAP_LOOKUP_ELEM:
  		err = map_lookup_elem(&attr);
  		break;
  	case BPF_MAP_UPDATE_ELEM:
  		err = map_update_elem(&attr, uattr);
  		break;
  	case BPF_MAP_DELETE_ELEM:
  		err = map_delete_elem(&attr);
  		break;
  	case BPF_MAP_GET_NEXT_KEY:
  		err = map_get_next_key(&attr);
  		break;
  	case BPF_MAP_FREEZE:
  		err = map_freeze(&attr);
  		break;
  	case BPF_PROG_LOAD:
  		err = bpf_prog_load(&attr, uattr);
  		break;
  	case BPF_OBJ_PIN:
  		err = bpf_obj_pin(&attr);
  		break;
  	case BPF_OBJ_GET:
  		err = bpf_obj_get(&attr);
  		break;
  	case BPF_PROG_ATTACH:
  		err = bpf_prog_attach(&attr);
  		break;
  	case BPF_PROG_DETACH:
  		err = bpf_prog_detach(&attr);
  		break;
  	case BPF_PROG_QUERY:
  		err = bpf_prog_query(&attr, uattr.user);
  		break;
  	case BPF_PROG_TEST_RUN:
  		err = bpf_prog_test_run(&attr, uattr.user);
  		break;
  	case BPF_PROG_GET_NEXT_ID:
  		err = bpf_obj_get_next_id(&attr, uattr.user,
  					  &prog_idr, &prog_idr_lock);
  		break;
  	case BPF_MAP_GET_NEXT_ID:
  		err = bpf_obj_get_next_id(&attr, uattr.user,
  					  &map_idr, &map_idr_lock);
  		break;
  	case BPF_BTF_GET_NEXT_ID:
  		err = bpf_obj_get_next_id(&attr, uattr.user,
  					  &btf_idr, &btf_idr_lock);
  		break;
  	case BPF_PROG_GET_FD_BY_ID:
  		err = bpf_prog_get_fd_by_id(&attr);
  		break;
  	case BPF_MAP_GET_FD_BY_ID:
  		err = bpf_map_get_fd_by_id(&attr);
  		break;
  	case BPF_OBJ_GET_INFO_BY_FD:
  		err = bpf_obj_get_info_by_fd(&attr, uattr.user);
  		break;
  	case BPF_RAW_TRACEPOINT_OPEN:
  		err = bpf_raw_tracepoint_open(&attr);
  		break;
  	case BPF_BTF_LOAD:
  		err = bpf_btf_load(&attr, uattr);
  		break;
  	case BPF_BTF_GET_FD_BY_ID:
  		err = bpf_btf_get_fd_by_id(&attr);
  		break;
  	case BPF_TASK_FD_QUERY:
  		err = bpf_task_fd_query(&attr, uattr.user);
  		break;
  	case BPF_MAP_LOOKUP_AND_DELETE_ELEM:
  		err = map_lookup_and_delete_elem(&attr);
  		break;
  	case BPF_MAP_LOOKUP_BATCH:
  		err = bpf_map_do_batch(&attr, uattr.user, BPF_MAP_LOOKUP_BATCH);
  		break;
  	case BPF_MAP_LOOKUP_AND_DELETE_BATCH:
  		err = bpf_map_do_batch(&attr, uattr.user,
  				       BPF_MAP_LOOKUP_AND_DELETE_BATCH);
  		break;
  	case BPF_MAP_UPDATE_BATCH:
  		err = bpf_map_do_batch(&attr, uattr.user, BPF_MAP_UPDATE_BATCH);
  		break;
  	case BPF_MAP_DELETE_BATCH:
  		err = bpf_map_do_batch(&attr, uattr.user, BPF_MAP_DELETE_BATCH);
  		break;
  	case BPF_LINK_CREATE:
  		err = link_create(&attr, uattr);
  		break;
  	case BPF_LINK_UPDATE:
  		err = link_update(&attr);
  		break;
  	case BPF_LINK_GET_FD_BY_ID:
  		err = bpf_link_get_fd_by_id(&attr);
  		break;
  	case BPF_LINK_GET_NEXT_ID:
  		err = bpf_obj_get_next_id(&attr, uattr.user,
  					  &link_idr, &link_idr_lock);
  		break;
  	case BPF_ENABLE_STATS:
  		err = bpf_enable_stats(&attr);
  		break;
  	case BPF_ITER_CREATE:
  		err = bpf_iter_create(&attr);
  		break;
  	case BPF_LINK_DETACH:
  		err = link_detach(&attr);
  		break;
  	case BPF_PROG_BIND_MAP:
  		err = bpf_prog_bind_map(&attr);
  		break;
  	default:
  		err = -EINVAL;
  		break;
  	}
  
  	return err;
  }
  
  SYSCALL_DEFINE3(bpf, int, cmd, union bpf_attr __user *, uattr, unsigned int, size)
  {
  	return __sys_bpf(cmd, USER_BPFPTR(uattr), size);
  }
  
  static bool syscall_prog_is_valid_access(int off, int size,
  					 enum bpf_access_type type,
  					 const struct bpf_prog *prog,
  					 struct bpf_insn_access_aux *info)
  {
  	if (off < 0 || off >= U16_MAX)
  		return false;
  	if (off % size != 0)
  		return false;
  	return true;
  }
  
  BPF_CALL_3(bpf_sys_bpf, int, cmd, union bpf_attr *, attr, u32, attr_size)
  {
  	struct bpf_prog * __maybe_unused prog;
  
  	switch (cmd) {
  	case BPF_MAP_CREATE:
  	case BPF_MAP_UPDATE_ELEM:
  	case BPF_MAP_FREEZE:
  	case BPF_PROG_LOAD:
  	case BPF_BTF_LOAD:
  	case BPF_LINK_CREATE:
  	case BPF_RAW_TRACEPOINT_OPEN:
  		break;
  #ifdef CONFIG_BPF_JIT /* __bpf_prog_enter_sleepable used by trampoline and JIT */
  	case BPF_PROG_TEST_RUN:
  		if (attr->test.data_in || attr->test.data_out ||
  		    attr->test.ctx_out || attr->test.duration ||
  		    attr->test.repeat || attr->test.flags)
  			return -EINVAL;
  
  		prog = bpf_prog_get_type(attr->test.prog_fd, BPF_PROG_TYPE_SYSCALL);
  		if (IS_ERR(prog))
  			return PTR_ERR(prog);
  
  		if (attr->test.ctx_size_in < prog->aux->max_ctx_offset ||
  		    attr->test.ctx_size_in > U16_MAX) {
  			bpf_prog_put(prog);
  			return -EINVAL;
  		}
  
  		if (!__bpf_prog_enter_sleepable(prog)) {
  			/* recursion detected */
  			bpf_prog_put(prog);
  			return -EBUSY;
  		}
  		attr->test.retval = bpf_prog_run(prog, (void *) (long) attr->test.ctx_in);
  		__bpf_prog_exit_sleepable(prog, 0 /* bpf_prog_run does runtime stats */);
  		bpf_prog_put(prog);
  		return 0;
  #endif
  	default:
  		return -EINVAL;
  	}
  	return __sys_bpf(cmd, KERNEL_BPFPTR(attr), attr_size);
  }
  EXPORT_SYMBOL(bpf_sys_bpf);
  
  static const struct bpf_func_proto bpf_sys_bpf_proto = {
  	.func		= bpf_sys_bpf,
  	.gpl_only	= false,
  	.ret_type	= RET_INTEGER,
  	.arg1_type	= ARG_ANYTHING,
  	.arg2_type	= ARG_PTR_TO_MEM | MEM_RDONLY,
  	.arg3_type	= ARG_CONST_SIZE,
  };
  
  const struct bpf_func_proto * __weak
  tracing_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
  {
  	return bpf_base_func_proto(func_id);
  }
  
  BPF_CALL_1(bpf_sys_close, u32, fd)
  {
  	/* When bpf program calls this helper there should not be
  	 * an fdget() without matching completed fdput().
  	 * This helper is allowed in the following callchain only:
  	 * sys_bpf->prog_test_run->bpf_prog->bpf_sys_close
  	 */
  	return close_fd(fd);
  }
  
  static const struct bpf_func_proto bpf_sys_close_proto = {
  	.func		= bpf_sys_close,
  	.gpl_only	= false,
  	.ret_type	= RET_INTEGER,
  	.arg1_type	= ARG_ANYTHING,
  };
  
  BPF_CALL_4(bpf_kallsyms_lookup_name, const char *, name, int, name_sz, int, flags, u64 *, res)
  {
  	if (flags)
  		return -EINVAL;
  
  	if (name_sz <= 1 || name[name_sz - 1])
  		return -EINVAL;
  
  	if (!bpf_dump_raw_ok(current_cred()))
  		return -EPERM;
  
  	*res = kallsyms_lookup_name(name);
  	return *res ? 0 : -ENOENT;
  }
  
  const struct bpf_func_proto bpf_kallsyms_lookup_name_proto = {
  	.func		= bpf_kallsyms_lookup_name,
  	.gpl_only	= false,
  	.ret_type	= RET_INTEGER,
  	.arg1_type	= ARG_PTR_TO_MEM,
  	.arg2_type	= ARG_CONST_SIZE_OR_ZERO,
  	.arg3_type	= ARG_ANYTHING,
  	.arg4_type	= ARG_PTR_TO_LONG,
  };
  
  static const struct bpf_func_proto *
  syscall_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
  {
  	switch (func_id) {
  	case BPF_FUNC_sys_bpf:
  		return &bpf_sys_bpf_proto;
  	case BPF_FUNC_btf_find_by_name_kind:
  		return &bpf_btf_find_by_name_kind_proto;
  	case BPF_FUNC_sys_close:
  		return &bpf_sys_close_proto;
  	case BPF_FUNC_kallsyms_lookup_name:
  		return &bpf_kallsyms_lookup_name_proto;
  	default:
  		return tracing_prog_func_proto(func_id, prog);
  	}
  }
  
  const struct bpf_verifier_ops bpf_syscall_verifier_ops = {
  	.get_func_proto  = syscall_prog_func_proto,
  	.is_valid_access = syscall_prog_is_valid_access,
  };
  
  const struct bpf_prog_ops bpf_syscall_prog_ops = {
  	.test_run = bpf_prog_test_run_syscall,
  };
  