TOMOYO Linux Cross Reference
Linux/kernel/bpf/helpers.c

   // SPDX-License-Identifier: GPL-2.0-only
   /* Copyright (c) 2011-2014 PLUMgrid, http://plumgrid.com
    */
   #include <linux/bpf.h>
   #include <linux/btf.h>
   #include <linux/bpf-cgroup.h>
   #include <linux/cgroup.h>
   #include <linux/rcupdate.h>
   #include <linux/random.h>
  #include <linux/smp.h>
  #include <linux/topology.h>
  #include <linux/ktime.h>
  #include <linux/sched.h>
  #include <linux/uidgid.h>
  #include <linux/filter.h>
  #include <linux/ctype.h>
  #include <linux/jiffies.h>
  #include <linux/pid_namespace.h>
  #include <linux/poison.h>
  #include <linux/proc_ns.h>
  #include <linux/sched/task.h>
  #include <linux/security.h>
  #include <linux/btf_ids.h>
  #include <linux/bpf_mem_alloc.h>
  #include <linux/kasan.h>
  
  #include "../../lib/kstrtox.h"
  
  /* If kernel subsystem is allowing eBPF programs to call this function,
   * inside its own verifier_ops->get_func_proto() callback it should return
   * bpf_map_lookup_elem_proto, so that verifier can properly check the arguments
   *
   * Different map implementations will rely on rcu in map methods
   * lookup/update/delete, therefore eBPF programs must run under rcu lock
   * if program is allowed to access maps, so check rcu_read_lock_held() or
   * rcu_read_lock_trace_held() in all three functions.
   */
  BPF_CALL_2(bpf_map_lookup_elem, struct bpf_map *, map, void *, key)
  {
          WARN_ON_ONCE(!rcu_read_lock_held() && !rcu_read_lock_trace_held() &&
                       !rcu_read_lock_bh_held());
          return (unsigned long) map->ops->map_lookup_elem(map, key);
  }
  
  const struct bpf_func_proto bpf_map_lookup_elem_proto = {
          .func           = bpf_map_lookup_elem,
          .gpl_only       = false,
          .pkt_access     = true,
          .ret_type       = RET_PTR_TO_MAP_VALUE_OR_NULL,
          .arg1_type      = ARG_CONST_MAP_PTR,
          .arg2_type      = ARG_PTR_TO_MAP_KEY,
  };
  
  BPF_CALL_4(bpf_map_update_elem, struct bpf_map *, map, void *, key,
             void *, value, u64, flags)
  {
          WARN_ON_ONCE(!rcu_read_lock_held() && !rcu_read_lock_trace_held() &&
                       !rcu_read_lock_bh_held());
          return map->ops->map_update_elem(map, key, value, flags);
  }
  
  const struct bpf_func_proto bpf_map_update_elem_proto = {
          .func           = bpf_map_update_elem,
          .gpl_only       = false,
          .pkt_access     = true,
          .ret_type       = RET_INTEGER,
          .arg1_type      = ARG_CONST_MAP_PTR,
          .arg2_type      = ARG_PTR_TO_MAP_KEY,
          .arg3_type      = ARG_PTR_TO_MAP_VALUE,
          .arg4_type      = ARG_ANYTHING,
  };
  
  BPF_CALL_2(bpf_map_delete_elem, struct bpf_map *, map, void *, key)
  {
          WARN_ON_ONCE(!rcu_read_lock_held() && !rcu_read_lock_trace_held() &&
                       !rcu_read_lock_bh_held());
          return map->ops->map_delete_elem(map, key);
  }
  
  const struct bpf_func_proto bpf_map_delete_elem_proto = {
          .func           = bpf_map_delete_elem,
          .gpl_only       = false,
          .pkt_access     = true,
          .ret_type       = RET_INTEGER,
          .arg1_type      = ARG_CONST_MAP_PTR,
          .arg2_type      = ARG_PTR_TO_MAP_KEY,
  };
  
  BPF_CALL_3(bpf_map_push_elem, struct bpf_map *, map, void *, value, u64, flags)
  {
          return map->ops->map_push_elem(map, value, flags);
  }
  
  const struct bpf_func_proto bpf_map_push_elem_proto = {
          .func           = bpf_map_push_elem,
          .gpl_only       = false,
          .pkt_access     = true,
          .ret_type       = RET_INTEGER,
          .arg1_type      = ARG_CONST_MAP_PTR,
         .arg2_type      = ARG_PTR_TO_MAP_VALUE,
         .arg3_type      = ARG_ANYTHING,
 };
 
 BPF_CALL_2(bpf_map_pop_elem, struct bpf_map *, map, void *, value)
 {
         return map->ops->map_pop_elem(map, value);
 }
 
 const struct bpf_func_proto bpf_map_pop_elem_proto = {
         .func           = bpf_map_pop_elem,
         .gpl_only       = false,
         .ret_type       = RET_INTEGER,
         .arg1_type      = ARG_CONST_MAP_PTR,
         .arg2_type      = ARG_PTR_TO_MAP_VALUE | MEM_UNINIT,
 };
 
 BPF_CALL_2(bpf_map_peek_elem, struct bpf_map *, map, void *, value)
 {
         return map->ops->map_peek_elem(map, value);
 }
 
 const struct bpf_func_proto bpf_map_peek_elem_proto = {
         .func           = bpf_map_peek_elem,
         .gpl_only       = false,
         .ret_type       = RET_INTEGER,
         .arg1_type      = ARG_CONST_MAP_PTR,
         .arg2_type      = ARG_PTR_TO_MAP_VALUE | MEM_UNINIT,
 };
 
 BPF_CALL_3(bpf_map_lookup_percpu_elem, struct bpf_map *, map, void *, key, u32, cpu)
 {
         WARN_ON_ONCE(!rcu_read_lock_held() && !rcu_read_lock_bh_held());
         return (unsigned long) map->ops->map_lookup_percpu_elem(map, key, cpu);
 }
 
 const struct bpf_func_proto bpf_map_lookup_percpu_elem_proto = {
         .func           = bpf_map_lookup_percpu_elem,
         .gpl_only       = false,
         .pkt_access     = true,
         .ret_type       = RET_PTR_TO_MAP_VALUE_OR_NULL,
         .arg1_type      = ARG_CONST_MAP_PTR,
         .arg2_type      = ARG_PTR_TO_MAP_KEY,
         .arg3_type      = ARG_ANYTHING,
 };
 
 const struct bpf_func_proto bpf_get_prandom_u32_proto = {
         .func           = bpf_user_rnd_u32,
         .gpl_only       = false,
         .ret_type       = RET_INTEGER,
 };
 
 BPF_CALL_0(bpf_get_smp_processor_id)
 {
         return smp_processor_id();
 }
 
 const struct bpf_func_proto bpf_get_smp_processor_id_proto = {
         .func           = bpf_get_smp_processor_id,
         .gpl_only       = false,
         .ret_type       = RET_INTEGER,
 };
 
 BPF_CALL_0(bpf_get_numa_node_id)
 {
         return numa_node_id();
 }
 
 const struct bpf_func_proto bpf_get_numa_node_id_proto = {
         .func           = bpf_get_numa_node_id,
         .gpl_only       = false,
         .ret_type       = RET_INTEGER,
 };
 
 BPF_CALL_0(bpf_ktime_get_ns)
 {
         /* NMI safe access to clock monotonic */
         return ktime_get_mono_fast_ns();
 }
 
 const struct bpf_func_proto bpf_ktime_get_ns_proto = {
         .func           = bpf_ktime_get_ns,
         .gpl_only       = false,
         .ret_type       = RET_INTEGER,
 };
 
 BPF_CALL_0(bpf_ktime_get_boot_ns)
 {
         /* NMI safe access to clock boottime */
         return ktime_get_boot_fast_ns();
 }
 
 const struct bpf_func_proto bpf_ktime_get_boot_ns_proto = {
         .func           = bpf_ktime_get_boot_ns,
         .gpl_only       = false,
         .ret_type       = RET_INTEGER,
 };
 
 BPF_CALL_0(bpf_ktime_get_coarse_ns)
 {
         return ktime_get_coarse_ns();
 }
 
 const struct bpf_func_proto bpf_ktime_get_coarse_ns_proto = {
         .func           = bpf_ktime_get_coarse_ns,
         .gpl_only       = false,
         .ret_type       = RET_INTEGER,
 };
 
 BPF_CALL_0(bpf_ktime_get_tai_ns)
 {
         /* NMI safe access to clock tai */
         return ktime_get_tai_fast_ns();
 }
 
 const struct bpf_func_proto bpf_ktime_get_tai_ns_proto = {
         .func           = bpf_ktime_get_tai_ns,
         .gpl_only       = false,
         .ret_type       = RET_INTEGER,
 };
 
 BPF_CALL_0(bpf_get_current_pid_tgid)
 {
         struct task_struct *task = current;
 
         if (unlikely(!task))
                 return -EINVAL;
 
         return (u64) task->tgid << 32 | task->pid;
 }
 
 const struct bpf_func_proto bpf_get_current_pid_tgid_proto = {
         .func           = bpf_get_current_pid_tgid,
         .gpl_only       = false,
         .ret_type       = RET_INTEGER,
 };
 
 BPF_CALL_0(bpf_get_current_uid_gid)
 {
         struct task_struct *task = current;
         kuid_t uid;
         kgid_t gid;
 
         if (unlikely(!task))
                 return -EINVAL;
 
         current_uid_gid(&uid, &gid);
         return (u64) from_kgid(&init_user_ns, gid) << 32 |
                      from_kuid(&init_user_ns, uid);
 }
 
 const struct bpf_func_proto bpf_get_current_uid_gid_proto = {
         .func           = bpf_get_current_uid_gid,
         .gpl_only       = false,
         .ret_type       = RET_INTEGER,
 };
 
 BPF_CALL_2(bpf_get_current_comm, char *, buf, u32, size)
 {
         struct task_struct *task = current;
 
         if (unlikely(!task))
                 goto err_clear;
 
         /* Verifier guarantees that size > 0 */
         strscpy_pad(buf, task->comm, size);
         return 0;
 err_clear:
         memset(buf, 0, size);
         return -EINVAL;
 }
 
 const struct bpf_func_proto bpf_get_current_comm_proto = {
         .func           = bpf_get_current_comm,
         .gpl_only       = false,
         .ret_type       = RET_INTEGER,
         .arg1_type      = ARG_PTR_TO_UNINIT_MEM,
         .arg2_type      = ARG_CONST_SIZE,
 };
 
 #if defined(CONFIG_QUEUED_SPINLOCKS) || defined(CONFIG_BPF_ARCH_SPINLOCK)
 
 static inline void __bpf_spin_lock(struct bpf_spin_lock *lock)
 {
         arch_spinlock_t *l = (void *)lock;
         union {
                 __u32 val;
                 arch_spinlock_t lock;
         } u = { .lock = __ARCH_SPIN_LOCK_UNLOCKED };
 
         compiletime_assert(u.val == 0, "__ARCH_SPIN_LOCK_UNLOCKED not 0");
         BUILD_BUG_ON(sizeof(*l) != sizeof(__u32));
         BUILD_BUG_ON(sizeof(*lock) != sizeof(__u32));
         preempt_disable();
         arch_spin_lock(l);
 }
 
 static inline void __bpf_spin_unlock(struct bpf_spin_lock *lock)
 {
         arch_spinlock_t *l = (void *)lock;
 
         arch_spin_unlock(l);
         preempt_enable();
 }
 
 #else
 
 static inline void __bpf_spin_lock(struct bpf_spin_lock *lock)
 {
         atomic_t *l = (void *)lock;
 
         BUILD_BUG_ON(sizeof(*l) != sizeof(*lock));
         do {
                 atomic_cond_read_relaxed(l, !VAL);
         } while (atomic_xchg(l, 1));
 }
 
 static inline void __bpf_spin_unlock(struct bpf_spin_lock *lock)
 {
         atomic_t *l = (void *)lock;
 
         atomic_set_release(l, 0);
 }
 
 #endif
 
 static DEFINE_PER_CPU(unsigned long, irqsave_flags);
 
 static inline void __bpf_spin_lock_irqsave(struct bpf_spin_lock *lock)
 {
         unsigned long flags;
 
         local_irq_save(flags);
         __bpf_spin_lock(lock);
         __this_cpu_write(irqsave_flags, flags);
 }
 
 NOTRACE_BPF_CALL_1(bpf_spin_lock, struct bpf_spin_lock *, lock)
 {
         __bpf_spin_lock_irqsave(lock);
         return 0;
 }
 
 const struct bpf_func_proto bpf_spin_lock_proto = {
         .func           = bpf_spin_lock,
         .gpl_only       = false,
         .ret_type       = RET_VOID,
         .arg1_type      = ARG_PTR_TO_SPIN_LOCK,
         .arg1_btf_id    = BPF_PTR_POISON,
 };
 
 static inline void __bpf_spin_unlock_irqrestore(struct bpf_spin_lock *lock)
 {
         unsigned long flags;
 
         flags = __this_cpu_read(irqsave_flags);
         __bpf_spin_unlock(lock);
         local_irq_restore(flags);
 }
 
 NOTRACE_BPF_CALL_1(bpf_spin_unlock, struct bpf_spin_lock *, lock)
 {
         __bpf_spin_unlock_irqrestore(lock);
         return 0;
 }
 
 const struct bpf_func_proto bpf_spin_unlock_proto = {
         .func           = bpf_spin_unlock,
         .gpl_only       = false,
         .ret_type       = RET_VOID,
         .arg1_type      = ARG_PTR_TO_SPIN_LOCK,
         .arg1_btf_id    = BPF_PTR_POISON,
 };
 
 void copy_map_value_locked(struct bpf_map *map, void *dst, void *src,
                            bool lock_src)
 {
         struct bpf_spin_lock *lock;
 
         if (lock_src)
                 lock = src + map->record->spin_lock_off;
         else
                 lock = dst + map->record->spin_lock_off;
         preempt_disable();
         __bpf_spin_lock_irqsave(lock);
         copy_map_value(map, dst, src);
         __bpf_spin_unlock_irqrestore(lock);
         preempt_enable();
 }
 
 BPF_CALL_0(bpf_jiffies64)
 {
         return get_jiffies_64();
 }
 
 const struct bpf_func_proto bpf_jiffies64_proto = {
         .func           = bpf_jiffies64,
         .gpl_only       = false,
         .ret_type       = RET_INTEGER,
 };
 
 #ifdef CONFIG_CGROUPS
 BPF_CALL_0(bpf_get_current_cgroup_id)
 {
         struct cgroup *cgrp;
         u64 cgrp_id;
 
         rcu_read_lock();
         cgrp = task_dfl_cgroup(current);
         cgrp_id = cgroup_id(cgrp);
         rcu_read_unlock();
 
         return cgrp_id;
 }
 
 const struct bpf_func_proto bpf_get_current_cgroup_id_proto = {
         .func           = bpf_get_current_cgroup_id,
         .gpl_only       = false,
         .ret_type       = RET_INTEGER,
 };
 
 BPF_CALL_1(bpf_get_current_ancestor_cgroup_id, int, ancestor_level)
 {
         struct cgroup *cgrp;
         struct cgroup *ancestor;
         u64 cgrp_id;
 
         rcu_read_lock();
         cgrp = task_dfl_cgroup(current);
         ancestor = cgroup_ancestor(cgrp, ancestor_level);
         cgrp_id = ancestor ? cgroup_id(ancestor) : 0;
         rcu_read_unlock();
 
         return cgrp_id;
 }
 
 const struct bpf_func_proto bpf_get_current_ancestor_cgroup_id_proto = {
         .func           = bpf_get_current_ancestor_cgroup_id,
         .gpl_only       = false,
         .ret_type       = RET_INTEGER,
         .arg1_type      = ARG_ANYTHING,
 };
 #endif /* CONFIG_CGROUPS */
 
 #define BPF_STRTOX_BASE_MASK 0x1F
 
 static int __bpf_strtoull(const char *buf, size_t buf_len, u64 flags,
                           unsigned long long *res, bool *is_negative)
 {
         unsigned int base = flags & BPF_STRTOX_BASE_MASK;
         const char *cur_buf = buf;
         size_t cur_len = buf_len;
         unsigned int consumed;
         size_t val_len;
         char str[64];
 
         if (!buf || !buf_len || !res || !is_negative)
                 return -EINVAL;
 
         if (base != 0 && base != 8 && base != 10 && base != 16)
                 return -EINVAL;
 
         if (flags & ~BPF_STRTOX_BASE_MASK)
                 return -EINVAL;
 
         while (cur_buf < buf + buf_len && isspace(*cur_buf))
                 ++cur_buf;
 
         *is_negative = (cur_buf < buf + buf_len && *cur_buf == '-');
         if (*is_negative)
                 ++cur_buf;
 
         consumed = cur_buf - buf;
         cur_len -= consumed;
         if (!cur_len)
                 return -EINVAL;
 
         cur_len = min(cur_len, sizeof(str) - 1);
         memcpy(str, cur_buf, cur_len);
         str[cur_len] = '\0';
         cur_buf = str;
 
         cur_buf = _parse_integer_fixup_radix(cur_buf, &base);
         val_len = _parse_integer(cur_buf, base, res);
 
         if (val_len & KSTRTOX_OVERFLOW)
                 return -ERANGE;
 
         if (val_len == 0)
                 return -EINVAL;
 
         cur_buf += val_len;
         consumed += cur_buf - str;
 
         return consumed;
 }
 
 static int __bpf_strtoll(const char *buf, size_t buf_len, u64 flags,
                          long long *res)
 {
         unsigned long long _res;
         bool is_negative;
         int err;
 
         err = __bpf_strtoull(buf, buf_len, flags, &_res, &is_negative);
         if (err < 0)
                 return err;
         if (is_negative) {
                 if ((long long)-_res > 0)
                         return -ERANGE;
                 *res = -_res;
         } else {
                 if ((long long)_res < 0)
                         return -ERANGE;
                 *res = _res;
         }
         return err;
 }
 
 BPF_CALL_4(bpf_strtol, const char *, buf, size_t, buf_len, u64, flags,
            s64 *, res)
 {
         long long _res;
         int err;
 
         *res = 0;
         err = __bpf_strtoll(buf, buf_len, flags, &_res);
         if (err < 0)
                 return err;
         if (_res != (long)_res)
                 return -ERANGE;
         *res = _res;
         return err;
 }
 
 const struct bpf_func_proto bpf_strtol_proto = {
         .func           = bpf_strtol,
         .gpl_only       = false,
         .ret_type       = RET_INTEGER,
         .arg1_type      = ARG_PTR_TO_MEM | MEM_RDONLY,
         .arg2_type      = ARG_CONST_SIZE,
         .arg3_type      = ARG_ANYTHING,
         .arg4_type      = ARG_PTR_TO_FIXED_SIZE_MEM | MEM_UNINIT | MEM_ALIGNED,
         .arg4_size      = sizeof(s64),
 };
 
 BPF_CALL_4(bpf_strtoul, const char *, buf, size_t, buf_len, u64, flags,
            u64 *, res)
 {
         unsigned long long _res;
         bool is_negative;
         int err;
 
         *res = 0;
         err = __bpf_strtoull(buf, buf_len, flags, &_res, &is_negative);
         if (err < 0)
                 return err;
         if (is_negative)
                 return -EINVAL;
         if (_res != (unsigned long)_res)
                 return -ERANGE;
         *res = _res;
         return err;
 }
 
 const struct bpf_func_proto bpf_strtoul_proto = {
         .func           = bpf_strtoul,
         .gpl_only       = false,
         .ret_type       = RET_INTEGER,
         .arg1_type      = ARG_PTR_TO_MEM | MEM_RDONLY,
         .arg2_type      = ARG_CONST_SIZE,
         .arg3_type      = ARG_ANYTHING,
         .arg4_type      = ARG_PTR_TO_FIXED_SIZE_MEM | MEM_UNINIT | MEM_ALIGNED,
         .arg4_size      = sizeof(u64),
 };
 
 BPF_CALL_3(bpf_strncmp, const char *, s1, u32, s1_sz, const char *, s2)
 {
         return strncmp(s1, s2, s1_sz);
 }
 
 static const struct bpf_func_proto bpf_strncmp_proto = {
         .func           = bpf_strncmp,
         .gpl_only       = false,
         .ret_type       = RET_INTEGER,
         .arg1_type      = ARG_PTR_TO_MEM | MEM_RDONLY,
         .arg2_type      = ARG_CONST_SIZE,
         .arg3_type      = ARG_PTR_TO_CONST_STR,
 };
 
 BPF_CALL_4(bpf_get_ns_current_pid_tgid, u64, dev, u64, ino,
            struct bpf_pidns_info *, nsdata, u32, size)
 {
         struct task_struct *task = current;
         struct pid_namespace *pidns;
         int err = -EINVAL;
 
         if (unlikely(size != sizeof(struct bpf_pidns_info)))
                 goto clear;
 
         if (unlikely((u64)(dev_t)dev != dev))
                 goto clear;
 
         if (unlikely(!task))
                 goto clear;
 
         pidns = task_active_pid_ns(task);
         if (unlikely(!pidns)) {
                 err = -ENOENT;
                 goto clear;
         }
 
         if (!ns_match(&pidns->ns, (dev_t)dev, ino))
                 goto clear;
 
         nsdata->pid = task_pid_nr_ns(task, pidns);
         nsdata->tgid = task_tgid_nr_ns(task, pidns);
         return 0;
 clear:
         memset((void *)nsdata, 0, (size_t) size);
         return err;
 }
 
 const struct bpf_func_proto bpf_get_ns_current_pid_tgid_proto = {
         .func           = bpf_get_ns_current_pid_tgid,
         .gpl_only       = false,
         .ret_type       = RET_INTEGER,
         .arg1_type      = ARG_ANYTHING,
         .arg2_type      = ARG_ANYTHING,
         .arg3_type      = ARG_PTR_TO_UNINIT_MEM,
         .arg4_type      = ARG_CONST_SIZE,
 };
 
 static const struct bpf_func_proto bpf_get_raw_smp_processor_id_proto = {
         .func           = bpf_get_raw_cpu_id,
         .gpl_only       = false,
         .ret_type       = RET_INTEGER,
 };
 
 BPF_CALL_5(bpf_event_output_data, void *, ctx, struct bpf_map *, map,
            u64, flags, void *, data, u64, size)
 {
         if (unlikely(flags & ~(BPF_F_INDEX_MASK)))
                 return -EINVAL;
 
         return bpf_event_output(map, flags, data, size, NULL, 0, NULL);
 }
 
 const struct bpf_func_proto bpf_event_output_data_proto =  {
         .func           = bpf_event_output_data,
         .gpl_only       = true,
         .ret_type       = RET_INTEGER,
         .arg1_type      = ARG_PTR_TO_CTX,
         .arg2_type      = ARG_CONST_MAP_PTR,
         .arg3_type      = ARG_ANYTHING,
         .arg4_type      = ARG_PTR_TO_MEM | MEM_RDONLY,
         .arg5_type      = ARG_CONST_SIZE_OR_ZERO,
 };
 
 BPF_CALL_3(bpf_copy_from_user, void *, dst, u32, size,
            const void __user *, user_ptr)
 {
         int ret = copy_from_user(dst, user_ptr, size);
 
         if (unlikely(ret)) {
                 memset(dst, 0, size);
                 ret = -EFAULT;
         }
 
         return ret;
 }
 
 const struct bpf_func_proto bpf_copy_from_user_proto = {
         .func           = bpf_copy_from_user,
         .gpl_only       = false,
         .might_sleep    = true,
         .ret_type       = RET_INTEGER,
         .arg1_type      = ARG_PTR_TO_UNINIT_MEM,
         .arg2_type      = ARG_CONST_SIZE_OR_ZERO,
         .arg3_type      = ARG_ANYTHING,
 };
 
 BPF_CALL_5(bpf_copy_from_user_task, void *, dst, u32, size,
            const void __user *, user_ptr, struct task_struct *, tsk, u64, flags)
 {
         int ret;
 
         /* flags is not used yet */
         if (unlikely(flags))
                 return -EINVAL;
 
         if (unlikely(!size))
                 return 0;
 
         ret = access_process_vm(tsk, (unsigned long)user_ptr, dst, size, 0);
         if (ret == size)
                 return 0;
 
         memset(dst, 0, size);
         /* Return -EFAULT for partial read */
         return ret < 0 ? ret : -EFAULT;
 }
 
 const struct bpf_func_proto bpf_copy_from_user_task_proto = {
         .func           = bpf_copy_from_user_task,
         .gpl_only       = true,
         .might_sleep    = true,
         .ret_type       = RET_INTEGER,
         .arg1_type      = ARG_PTR_TO_UNINIT_MEM,
         .arg2_type      = ARG_CONST_SIZE_OR_ZERO,
         .arg3_type      = ARG_ANYTHING,
         .arg4_type      = ARG_PTR_TO_BTF_ID,
         .arg4_btf_id    = &btf_tracing_ids[BTF_TRACING_TYPE_TASK],
         .arg5_type      = ARG_ANYTHING
 };
 
 BPF_CALL_2(bpf_per_cpu_ptr, const void *, ptr, u32, cpu)
 {
         if (cpu >= nr_cpu_ids)
                 return (unsigned long)NULL;
 
         return (unsigned long)per_cpu_ptr((const void __percpu *)ptr, cpu);
 }
 
 const struct bpf_func_proto bpf_per_cpu_ptr_proto = {
         .func           = bpf_per_cpu_ptr,
         .gpl_only       = false,
         .ret_type       = RET_PTR_TO_MEM_OR_BTF_ID | PTR_MAYBE_NULL | MEM_RDONLY,
         .arg1_type      = ARG_PTR_TO_PERCPU_BTF_ID,
         .arg2_type      = ARG_ANYTHING,
 };
 
 BPF_CALL_1(bpf_this_cpu_ptr, const void *, percpu_ptr)
 {
         return (unsigned long)this_cpu_ptr((const void __percpu *)percpu_ptr);
 }
 
 const struct bpf_func_proto bpf_this_cpu_ptr_proto = {
         .func           = bpf_this_cpu_ptr,
         .gpl_only       = false,
         .ret_type       = RET_PTR_TO_MEM_OR_BTF_ID | MEM_RDONLY,
         .arg1_type      = ARG_PTR_TO_PERCPU_BTF_ID,
 };
 
 static int bpf_trace_copy_string(char *buf, void *unsafe_ptr, char fmt_ptype,
                 size_t bufsz)
 {
         void __user *user_ptr = (__force void __user *)unsafe_ptr;
 
         buf[0] = 0;
 
         switch (fmt_ptype) {
         case 's':
 #ifdef CONFIG_ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE
                 if ((unsigned long)unsafe_ptr < TASK_SIZE)
                         return strncpy_from_user_nofault(buf, user_ptr, bufsz);
                 fallthrough;
 #endif
         case 'k':
                 return strncpy_from_kernel_nofault(buf, unsafe_ptr, bufsz);
         case 'u':
                 return strncpy_from_user_nofault(buf, user_ptr, bufsz);
         }
 
         return -EINVAL;
 }
 
 /* Per-cpu temp buffers used by printf-like helpers to store the bprintf binary
  * arguments representation.
  */
 #define MAX_BPRINTF_BIN_ARGS    512
 
 /* Support executing three nested bprintf helper calls on a given CPU */
 #define MAX_BPRINTF_NEST_LEVEL  3
 struct bpf_bprintf_buffers {
         char bin_args[MAX_BPRINTF_BIN_ARGS];
         char buf[MAX_BPRINTF_BUF];
 };
 
 static DEFINE_PER_CPU(struct bpf_bprintf_buffers[MAX_BPRINTF_NEST_LEVEL], bpf_bprintf_bufs);
 static DEFINE_PER_CPU(int, bpf_bprintf_nest_level);
 
 static int try_get_buffers(struct bpf_bprintf_buffers **bufs)
 {
         int nest_level;
 
         preempt_disable();
         nest_level = this_cpu_inc_return(bpf_bprintf_nest_level);
         if (WARN_ON_ONCE(nest_level > MAX_BPRINTF_NEST_LEVEL)) {
                 this_cpu_dec(bpf_bprintf_nest_level);
                 preempt_enable();
                 return -EBUSY;
         }
         *bufs = this_cpu_ptr(&bpf_bprintf_bufs[nest_level - 1]);
 
         return 0;
 }
 
 void bpf_bprintf_cleanup(struct bpf_bprintf_data *data)
 {
         if (!data->bin_args && !data->buf)
                 return;
         if (WARN_ON_ONCE(this_cpu_read(bpf_bprintf_nest_level) == 0))
                 return;
         this_cpu_dec(bpf_bprintf_nest_level);
         preempt_enable();
 }
 
 /*
  * bpf_bprintf_prepare - Generic pass on format strings for bprintf-like helpers
  *
  * Returns a negative value if fmt is an invalid format string or 0 otherwise.
  *
  * This can be used in two ways:
  * - Format string verification only: when data->get_bin_args is false
  * - Arguments preparation: in addition to the above verification, it writes in
  *   data->bin_args a binary representation of arguments usable by bstr_printf
  *   where pointers from BPF have been sanitized.
  *
  * In argument preparation mode, if 0 is returned, safe temporary buffers are
  * allocated and bpf_bprintf_cleanup should be called to free them after use.
  */
 int bpf_bprintf_prepare(char *fmt, u32 fmt_size, const u64 *raw_args,
                         u32 num_args, struct bpf_bprintf_data *data)
 {
         bool get_buffers = (data->get_bin_args && num_args) || data->get_buf;
         char *unsafe_ptr = NULL, *tmp_buf = NULL, *tmp_buf_end, *fmt_end;
         struct bpf_bprintf_buffers *buffers = NULL;
         size_t sizeof_cur_arg, sizeof_cur_ip;
         int err, i, num_spec = 0;
         u64 cur_arg;
         char fmt_ptype, cur_ip[16], ip_spec[] = "%pXX";
 
         fmt_end = strnchr(fmt, fmt_size, 0);
         if (!fmt_end)
                 return -EINVAL;
         fmt_size = fmt_end - fmt;
 
         if (get_buffers && try_get_buffers(&buffers))
                 return -EBUSY;
 
         if (data->get_bin_args) {
                 if (num_args)
                         tmp_buf = buffers->bin_args;
                 tmp_buf_end = tmp_buf + MAX_BPRINTF_BIN_ARGS;
                 data->bin_args = (u32 *)tmp_buf;
         }
 
         if (data->get_buf)
                 data->buf = buffers->buf;
 
         for (i = 0; i < fmt_size; i++) {
                 if ((!isprint(fmt[i]) && !isspace(fmt[i])) || !isascii(fmt[i])) {
                         err = -EINVAL;
                         goto out;
                 }
 
                 if (fmt[i] != '%')
                         continue;
 
                 if (fmt[i + 1] == '%') {
                         i++;
                         continue;
                 }
 
                 if (num_spec >= num_args) {
                         err = -EINVAL;
                         goto out;
                 }
 
                 /* The string is zero-terminated so if fmt[i] != 0, we can
                  * always access fmt[i + 1], in the worst case it will be a 0
                  */
                 i++;
 
                 /* skip optional "[0 +-][num]" width formatting field */
                 while (fmt[i] == '' || fmt[i] == '+'  || fmt[i] == '-' ||
                        fmt[i] == ' ')
                         i++;
                 if (fmt[i] >= '1' && fmt[i] <= '9') {
                         i++;
                         while (fmt[i] >= '' && fmt[i] <= '9')
                                 i++;
                 }
 
                 if (fmt[i] == 'p') {
                         sizeof_cur_arg = sizeof(long);
 
                         if ((fmt[i + 1] == 'k' || fmt[i + 1] == 'u') &&
                             fmt[i + 2] == 's') {
                                 fmt_ptype = fmt[i + 1];
                                 i += 2;
                                 goto fmt_str;
                         }
 
                         if (fmt[i + 1] == 0 || isspace(fmt[i + 1]) ||
                             ispunct(fmt[i + 1]) || fmt[i + 1] == 'K' ||
                             fmt[i + 1] == 'x' || fmt[i + 1] == 's' ||
                             fmt[i + 1] == 'S') {
                                 /* just kernel pointers */
                                 if (tmp_buf)
                                         cur_arg = raw_args[num_spec];
                                 i++;
                                 goto nocopy_fmt;
                         }
 
                         if (fmt[i + 1] == 'B') {
                                 if (tmp_buf)  {
                                         err = snprintf(tmp_buf,
                                                        (tmp_buf_end - tmp_buf),
                                                        "%pB",
                                                        (void *)(long)raw_args[num_spec]);
                                         tmp_buf += (err + 1);
                                 }
 
                                 i++;
                                 num_spec++;
                                 continue;
                         }
 
                         /* only support "%pI4", "%pi4", "%pI6" and "%pi6". */
                         if ((fmt[i + 1] != 'i' && fmt[i + 1] != 'I') ||
                             (fmt[i + 2] != '4' && fmt[i + 2] != '6')) {
                                 err = -EINVAL;
                                 goto out;
                         }
 
                         i += 2;
                         if (!tmp_buf)
                                 goto nocopy_fmt;
 
                         sizeof_cur_ip = (fmt[i] == '4') ? 4 : 16;
                         if (tmp_buf_end - tmp_buf < sizeof_cur_ip) {
                                 err = -ENOSPC;
                                 goto out;
                         }
 
                         unsafe_ptr = (char *)(long)raw_args[num_spec];
                         err = copy_from_kernel_nofault(cur_ip, unsafe_ptr,
                                                        sizeof_cur_ip);
                         if (err < 0)
                                 memset(cur_ip, 0, sizeof_cur_ip);
 
                         /* hack: bstr_printf expects IP addresses to be
                          * pre-formatted as strings, ironically, the easiest way
                          * to do that is to call snprintf.
                          */
                         ip_spec[2] = fmt[i - 1];
                         ip_spec[3] = fmt[i];
                         err = snprintf(tmp_buf, tmp_buf_end - tmp_buf,
                                        ip_spec, &cur_ip);
 
                         tmp_buf += err + 1;
                         num_spec++;
 
                         continue;
                 } else if (fmt[i] == 's') {
                         fmt_ptype = fmt[i];
 fmt_str:
                         if (fmt[i + 1] != 0 &&
                             !isspace(fmt[i + 1]) &&
                             !ispunct(fmt[i + 1])) {
                                 err = -EINVAL;
                                 goto out;
                         }
 
                         if (!tmp_buf)
                                 goto nocopy_fmt;
 
                         if (tmp_buf_end == tmp_buf) {
                                 err = -ENOSPC;
                                 goto out;
                         }
 
                         unsafe_ptr = (char *)(long)raw_args[num_spec];
                         err = bpf_trace_copy_string(tmp_buf, unsafe_ptr,
                                                     fmt_ptype,
                                                     tmp_buf_end - tmp_buf);
                         if (err < 0) {
                                 tmp_buf[0] = '\0';
                                 err = 1;
                         }
 
                         tmp_buf += err;
                         num_spec++;
 
                         continue;
                 } else if (fmt[i] == 'c') {
                         if (!tmp_buf)
                                 goto nocopy_fmt;
 
                         if (tmp_buf_end == tmp_buf) {
                                 err = -ENOSPC;
                                 goto out;
                         }
 
                         *tmp_buf = raw_args[num_spec];
                         tmp_buf++;
                         num_spec++;
 
                         continue;
                 }
 
                 sizeof_cur_arg = sizeof(int);
 
                 if (fmt[i] == 'l') {
                         sizeof_cur_arg = sizeof(long);
                         i++;
                 }
                 if (fmt[i] == 'l') {
                         sizeof_cur_arg = sizeof(long long);
                         i++;
                 }
 
                 if (fmt[i] != 'i' && fmt[i] != 'd' && fmt[i] != 'u' &&
                     fmt[i] != 'x' && fmt[i] != 'X') {
                         err = -EINVAL;
                         goto out;
                 }
 
                 if (tmp_buf)
                         cur_arg = raw_args[num_spec];
 nocopy_fmt:
                 if (tmp_buf) {
                         tmp_buf = PTR_ALIGN(tmp_buf, sizeof(u32));
                         if (tmp_buf_end - tmp_buf < sizeof_cur_arg) {
                                 err = -ENOSPC;
                                 goto out;
                         }
 
                         if (sizeof_cur_arg == 8) {
                                 *(u32 *)tmp_buf = *(u32 *)&cur_arg;
                                 *(u32 *)(tmp_buf + 4) = *((u32 *)&cur_arg + 1);
                         } else {
                                 *(u32 *)tmp_buf = (u32)(long)cur_arg;
                         }
                         tmp_buf += sizeof_cur_arg;
                 }
                 num_spec++;
         }
 
         err = 0;
 out:
         if (err)
                 bpf_bprintf_cleanup(data);
         return err;
 }
 
 BPF_CALL_5(bpf_snprintf, char *, str, u32, str_size, char *, fmt,
            const void *, args, u32, data_len)
 {
         struct bpf_bprintf_data data = {
                 .get_bin_args   = true,
         };
         int err, num_args;
 
         if (data_len % 8 || data_len > MAX_BPRINTF_VARARGS * 8 ||
             (data_len && !args))
                 return -EINVAL;
         num_args = data_len / 8;
 
         /* ARG_PTR_TO_CONST_STR guarantees that fmt is zero-terminated so we
          * can safely give an unbounded size.
          */
         err = bpf_bprintf_prepare(fmt, UINT_MAX, args, num_args, &data);
         if (err < 0)
                 return err;
 
         err = bstr_printf(str, str_size, fmt, data.bin_args);
 
         bpf_bprintf_cleanup(&data);
 
         return err + 1;
 }
 
 const struct bpf_func_proto bpf_snprintf_proto = {
         .func           = bpf_snprintf,
         .gpl_only       = true,
         .ret_type       = RET_INTEGER,
         .arg1_type      = ARG_PTR_TO_MEM_OR_NULL,
         .arg2_type      = ARG_CONST_SIZE_OR_ZERO,
         .arg3_type      = ARG_PTR_TO_CONST_STR,
         .arg4_type      = ARG_PTR_TO_MEM | PTR_MAYBE_NULL | MEM_RDONLY,
         .arg5_type      = ARG_CONST_SIZE_OR_ZERO,
 };
 
 struct bpf_async_cb {
         struct bpf_map *map;
         struct bpf_prog *prog;
         void __rcu *callback_fn;
         void *value;
         union {
                 struct rcu_head rcu;
                 struct work_struct delete_work;
         };
         u64 flags;
 };
 
 /* BPF map elements can contain 'struct bpf_timer'.
  * Such map owns all of its BPF timers.
  * 'struct bpf_timer' is allocated as part of map element allocation
  * and it's zero initialized.
  * That space is used to keep 'struct bpf_async_kern'.
  * bpf_timer_init() allocates 'struct bpf_hrtimer', inits hrtimer, and
  * remembers 'struct bpf_map *' pointer it's part of.
  * bpf_timer_set_callback() increments prog refcnt and assign bpf callback_fn.
  * bpf_timer_start() arms the timer.
  * If user space reference to a map goes to zero at this point
  * ops->map_release_uref callback is responsible for cancelling the timers,
  * freeing their memory, and decrementing prog's refcnts.
  * bpf_timer_cancel() cancels the timer and decrements prog's refcnt.
  * Inner maps can contain bpf timers as well. ops->map_release_uref is
  * freeing the timers when inner map is replaced or deleted by user space.
  */
 struct bpf_hrtimer {
         struct bpf_async_cb cb;
         struct hrtimer timer;
         atomic_t cancelling;
 };
 
 struct bpf_work {
         struct bpf_async_cb cb;
         struct work_struct work;
         struct work_struct delete_work;
 };
 
 /* the actual struct hidden inside uapi struct bpf_timer and bpf_wq */
 struct bpf_async_kern {
         union {
                 struct bpf_async_cb *cb;
                 struct bpf_hrtimer *timer;
                 struct bpf_work *work;
         };
         /* bpf_spin_lock is used here instead of spinlock_t to make
          * sure that it always fits into space reserved by struct bpf_timer
          * regardless of LOCKDEP and spinlock debug flags.
          */
         struct bpf_spin_lock lock;
 } __attribute__((aligned(8)));
 
 enum bpf_async_type {
         BPF_ASYNC_TYPE_TIMER = 0,
         BPF_ASYNC_TYPE_WQ,
 };
 
 static DEFINE_PER_CPU(struct bpf_hrtimer *, hrtimer_running);
 
 static enum hrtimer_restart bpf_timer_cb(struct hrtimer *hrtimer)
 {
         struct bpf_hrtimer *t = container_of(hrtimer, struct bpf_hrtimer, timer);
         struct bpf_map *map = t->cb.map;
         void *value = t->cb.value;
         bpf_callback_t callback_fn;
         void *key;
         u32 idx;
 
         BTF_TYPE_EMIT(struct bpf_timer);
         callback_fn = rcu_dereference_check(t->cb.callback_fn, rcu_read_lock_bh_held());
         if (!callback_fn)
                 goto out;
 
         /* bpf_timer_cb() runs in hrtimer_run_softirq. It doesn't migrate and
          * cannot be preempted by another bpf_timer_cb() on the same cpu.
          * Remember the timer this callback is servicing to prevent
          * deadlock if callback_fn() calls bpf_timer_cancel() or
          * bpf_map_delete_elem() on the same timer.
          */
         this_cpu_write(hrtimer_running, t);
         if (map->map_type == BPF_MAP_TYPE_ARRAY) {
                 struct bpf_array *array = container_of(map, struct bpf_array, map);
 
                 /* compute the key */
                 idx = ((char *)value - array->value) / array->elem_size;
                 key = &idx;
         } else { /* hash or lru */
                 key = value - round_up(map->key_size, 8);
         }
 
         callback_fn((u64)(long)map, (u64)(long)key, (u64)(long)value, 0, 0);
         /* The verifier checked that return value is zero. */
 
         this_cpu_write(hrtimer_running, NULL);
 out:
         return HRTIMER_NORESTART;
 }
 
 static void bpf_wq_work(struct work_struct *work)
 {
         struct bpf_work *w = container_of(work, struct bpf_work, work);
         struct bpf_async_cb *cb = &w->cb;
         struct bpf_map *map = cb->map;
         bpf_callback_t callback_fn;
         void *value = cb->value;
         void *key;
         u32 idx;
 
         BTF_TYPE_EMIT(struct bpf_wq);
 
         callback_fn = READ_ONCE(cb->callback_fn);
         if (!callback_fn)
                 return;
 
         if (map->map_type == BPF_MAP_TYPE_ARRAY) {
                 struct bpf_array *array = container_of(map, struct bpf_array, map);
 
                 /* compute the key */
                 idx = ((char *)value - array->value) / array->elem_size;
                 key = &idx;
         } else { /* hash or lru */
                 key = value - round_up(map->key_size, 8);
         }
 
         rcu_read_lock_trace();
         migrate_disable();
 
         callback_fn((u64)(long)map, (u64)(long)key, (u64)(long)value, 0, 0);
 
         migrate_enable();
         rcu_read_unlock_trace();
 }
 
 static void bpf_wq_delete_work(struct work_struct *work)
 {
         struct bpf_work *w = container_of(work, struct bpf_work, delete_work);
 
         cancel_work_sync(&w->work);
 
         kfree_rcu(w, cb.rcu);
 }
 
 static void bpf_timer_delete_work(struct work_struct *work)
 {
         struct bpf_hrtimer *t = container_of(work, struct bpf_hrtimer, cb.delete_work);
 
         /* Cancel the timer and wait for callback to complete if it was running.
          * If hrtimer_cancel() can be safely called it's safe to call
          * kfree_rcu(t) right after for both preallocated and non-preallocated
          * maps.  The async->cb = NULL was already done and no code path can see
          * address 't' anymore. Timer if armed for existing bpf_hrtimer before
          * bpf_timer_cancel_and_free will have been cancelled.
          */
         hrtimer_cancel(&t->timer);
         kfree_rcu(t, cb.rcu);
 }
 
 static int __bpf_async_init(struct bpf_async_kern *async, struct bpf_map *map, u64 flags,
                             enum bpf_async_type type)
 {
         struct bpf_async_cb *cb;
         struct bpf_hrtimer *t;
         struct bpf_work *w;
         clockid_t clockid;
         size_t size;
         int ret = 0;
 
         if (in_nmi())
                 return -EOPNOTSUPP;
 
         switch (type) {
         case BPF_ASYNC_TYPE_TIMER:
                 size = sizeof(struct bpf_hrtimer);
                 break;
         case BPF_ASYNC_TYPE_WQ:
                 size = sizeof(struct bpf_work);
                 break;
         default:
                 return -EINVAL;
         }
 
         __bpf_spin_lock_irqsave(&async->lock);
         t = async->timer;
         if (t) {
                 ret = -EBUSY;
                 goto out;
         }
 
         /* allocate hrtimer via map_kmalloc to use memcg accounting */
         cb = bpf_map_kmalloc_node(map, size, GFP_ATOMIC, map->numa_node);
         if (!cb) {
                 ret = -ENOMEM;
                 goto out;
         }
 
         switch (type) {
         case BPF_ASYNC_TYPE_TIMER:
                 clockid = flags & (MAX_CLOCKS - 1);
                 t = (struct bpf_hrtimer *)cb;
 
                 atomic_set(&t->cancelling, 0);
                 INIT_WORK(&t->cb.delete_work, bpf_timer_delete_work);
                 hrtimer_init(&t->timer, clockid, HRTIMER_MODE_REL_SOFT);
                 t->timer.function = bpf_timer_cb;
                 cb->value = (void *)async - map->record->timer_off;
                 break;
         case BPF_ASYNC_TYPE_WQ:
                 w = (struct bpf_work *)cb;
 
                 INIT_WORK(&w->work, bpf_wq_work);
                 INIT_WORK(&w->delete_work, bpf_wq_delete_work);
                 cb->value = (void *)async - map->record->wq_off;
                 break;
         }
         cb->map = map;
         cb->prog = NULL;
         cb->flags = flags;
         rcu_assign_pointer(cb->callback_fn, NULL);
 
         WRITE_ONCE(async->cb, cb);
         /* Guarantee the order between async->cb and map->usercnt. So
          * when there are concurrent uref release and bpf timer init, either
          * bpf_timer_cancel_and_free() called by uref release reads a no-NULL
          * timer or atomic64_read() below returns a zero usercnt.
          */
         smp_mb();
         if (!atomic64_read(&map->usercnt)) {
                 /* maps with timers must be either held by user space
                  * or pinned in bpffs.
                  */
                 WRITE_ONCE(async->cb, NULL);
                 kfree(cb);
                 ret = -EPERM;
         }
 out:
         __bpf_spin_unlock_irqrestore(&async->lock);
         return ret;
 }
 
 BPF_CALL_3(bpf_timer_init, struct bpf_async_kern *, timer, struct bpf_map *, map,
            u64, flags)
 {
         clock_t clockid = flags & (MAX_CLOCKS - 1);
 
         BUILD_BUG_ON(MAX_CLOCKS != 16);
         BUILD_BUG_ON(sizeof(struct bpf_async_kern) > sizeof(struct bpf_timer));
         BUILD_BUG_ON(__alignof__(struct bpf_async_kern) != __alignof__(struct bpf_timer));
 
         if (flags >= MAX_CLOCKS ||
             /* similar to timerfd except _ALARM variants are not supported */
             (clockid != CLOCK_MONOTONIC &&
              clockid != CLOCK_REALTIME &&
              clockid != CLOCK_BOOTTIME))
                 return -EINVAL;
 
         return __bpf_async_init(timer, map, flags, BPF_ASYNC_TYPE_TIMER);
 }
 
 static const struct bpf_func_proto bpf_timer_init_proto = {
         .func           = bpf_timer_init,
         .gpl_only       = true,
         .ret_type       = RET_INTEGER,
         .arg1_type      = ARG_PTR_TO_TIMER,
         .arg2_type      = ARG_CONST_MAP_PTR,
         .arg3_type      = ARG_ANYTHING,
 };
 
 static int __bpf_async_set_callback(struct bpf_async_kern *async, void *callback_fn,
                                     struct bpf_prog_aux *aux, unsigned int flags,
                                     enum bpf_async_type type)
 {
         struct bpf_prog *prev, *prog = aux->prog;
         struct bpf_async_cb *cb;
         int ret = 0;
 
         if (in_nmi())
                 return -EOPNOTSUPP;
         __bpf_spin_lock_irqsave(&async->lock);
         cb = async->cb;
         if (!cb) {
                 ret = -EINVAL;
                 goto out;
         }
         if (!atomic64_read(&cb->map->usercnt)) {
                 /* maps with timers must be either held by user space
                  * or pinned in bpffs. Otherwise timer might still be
                  * running even when bpf prog is detached and user space
                  * is gone, since map_release_uref won't ever be called.
                  */
                 ret = -EPERM;
                 goto out;
         }
         prev = cb->prog;
         if (prev != prog) {
                 /* Bump prog refcnt once. Every bpf_timer_set_callback()
                  * can pick different callback_fn-s within the same prog.
                  */
                 prog = bpf_prog_inc_not_zero(prog);
                 if (IS_ERR(prog)) {
                         ret = PTR_ERR(prog);
                         goto out;
                 }
                 if (prev)
                         /* Drop prev prog refcnt when swapping with new prog */
                         bpf_prog_put(prev);
                 cb->prog = prog;
         }
         rcu_assign_pointer(cb->callback_fn, callback_fn);
 out:
         __bpf_spin_unlock_irqrestore(&async->lock);
         return ret;
 }
 
 BPF_CALL_3(bpf_timer_set_callback, struct bpf_async_kern *, timer, void *, callback_fn,
            struct bpf_prog_aux *, aux)
 {
         return __bpf_async_set_callback(timer, callback_fn, aux, 0, BPF_ASYNC_TYPE_TIMER);
 }
 
 static const struct bpf_func_proto bpf_timer_set_callback_proto = {
         .func           = bpf_timer_set_callback,
         .gpl_only       = true,
         .ret_type       = RET_INTEGER,
         .arg1_type      = ARG_PTR_TO_TIMER,
         .arg2_type      = ARG_PTR_TO_FUNC,
 };
 
 BPF_CALL_3(bpf_timer_start, struct bpf_async_kern *, timer, u64, nsecs, u64, flags)
 {
         struct bpf_hrtimer *t;
         int ret = 0;
         enum hrtimer_mode mode;
 
         if (in_nmi())
                 return -EOPNOTSUPP;
         if (flags & ~(BPF_F_TIMER_ABS | BPF_F_TIMER_CPU_PIN))
                 return -EINVAL;
         __bpf_spin_lock_irqsave(&timer->lock);
         t = timer->timer;
         if (!t || !t->cb.prog) {
                 ret = -EINVAL;
                 goto out;
         }
 
         if (flags & BPF_F_TIMER_ABS)
                 mode = HRTIMER_MODE_ABS_SOFT;
         else
                 mode = HRTIMER_MODE_REL_SOFT;
 
         if (flags & BPF_F_TIMER_CPU_PIN)
                 mode |= HRTIMER_MODE_PINNED;
 
         hrtimer_start(&t->timer, ns_to_ktime(nsecs), mode);
 out:
         __bpf_spin_unlock_irqrestore(&timer->lock);
         return ret;
 }
 
 static const struct bpf_func_proto bpf_timer_start_proto = {
         .func           = bpf_timer_start,
         .gpl_only       = true,
         .ret_type       = RET_INTEGER,
         .arg1_type      = ARG_PTR_TO_TIMER,
         .arg2_type      = ARG_ANYTHING,
         .arg3_type      = ARG_ANYTHING,
 };
 
 static void drop_prog_refcnt(struct bpf_async_cb *async)
 {
         struct bpf_prog *prog = async->prog;
 
         if (prog) {
                 bpf_prog_put(prog);
                 async->prog = NULL;
                 rcu_assign_pointer(async->callback_fn, NULL);
         }
 }
 
 BPF_CALL_1(bpf_timer_cancel, struct bpf_async_kern *, timer)
 {
         struct bpf_hrtimer *t, *cur_t;
         bool inc = false;
         int ret = 0;
 
         if (in_nmi())
                 return -EOPNOTSUPP;
         rcu_read_lock();
         __bpf_spin_lock_irqsave(&timer->lock);
         t = timer->timer;
         if (!t) {
                 ret = -EINVAL;
                 goto out;
         }
 
         cur_t = this_cpu_read(hrtimer_running);
         if (cur_t == t) {
                 /* If bpf callback_fn is trying to bpf_timer_cancel()
                  * its own timer the hrtimer_cancel() will deadlock
                  * since it waits for callback_fn to finish.
                  */
                 ret = -EDEADLK;
                 goto out;
         }
 
         /* Only account in-flight cancellations when invoked from a timer
          * callback, since we want to avoid waiting only if other _callbacks_
          * are waiting on us, to avoid introducing lockups. Non-callback paths
          * are ok, since nobody would synchronously wait for their completion.
          */
         if (!cur_t)
                 goto drop;
         atomic_inc(&t->cancelling);
         /* Need full barrier after relaxed atomic_inc */
         smp_mb__after_atomic();
         inc = true;
         if (atomic_read(&cur_t->cancelling)) {
                 /* We're cancelling timer t, while some other timer callback is
                  * attempting to cancel us. In such a case, it might be possible
                  * that timer t belongs to the other callback, or some other
                  * callback waiting upon it (creating transitive dependencies
                  * upon us), and we will enter a deadlock if we continue
                  * cancelling and waiting for it synchronously, since it might
                  * do the same. Bail!
                  */
                 ret = -EDEADLK;
                 goto out;
         }
 drop:
         drop_prog_refcnt(&t->cb);
 out:
         __bpf_spin_unlock_irqrestore(&timer->lock);
         /* Cancel the timer and wait for associated callback to finish
          * if it was running.
          */
         ret = ret ?: hrtimer_cancel(&t->timer);
         if (inc)
                 atomic_dec(&t->cancelling);
         rcu_read_unlock();
         return ret;
 }
 
 static const struct bpf_func_proto bpf_timer_cancel_proto = {
         .func           = bpf_timer_cancel,
         .gpl_only       = true,
         .ret_type       = RET_INTEGER,
         .arg1_type      = ARG_PTR_TO_TIMER,
 };
 
 static struct bpf_async_cb *__bpf_async_cancel_and_free(struct bpf_async_kern *async)
 {
         struct bpf_async_cb *cb;
 
         /* Performance optimization: read async->cb without lock first. */
         if (!READ_ONCE(async->cb))
                 return NULL;
 
         __bpf_spin_lock_irqsave(&async->lock);
         /* re-read it under lock */
         cb = async->cb;
         if (!cb)
                 goto out;
         drop_prog_refcnt(cb);
         /* The subsequent bpf_timer_start/cancel() helpers won't be able to use
          * this timer, since it won't be initialized.
          */
         WRITE_ONCE(async->cb, NULL);
 out:
         __bpf_spin_unlock_irqrestore(&async->lock);
         return cb;
 }
 
 /* This function is called by map_delete/update_elem for individual element and
  * by ops->map_release_uref when the user space reference to a map reaches zero.
  */
 void bpf_timer_cancel_and_free(void *val)
 {
         struct bpf_hrtimer *t;
 
         t = (struct bpf_hrtimer *)__bpf_async_cancel_and_free(val);
 
         if (!t)
                 return;
         /* We check that bpf_map_delete/update_elem() was called from timer
          * callback_fn. In such case we don't call hrtimer_cancel() (since it
          * will deadlock) and don't call hrtimer_try_to_cancel() (since it will
          * just return -1). Though callback_fn is still running on this cpu it's
          * safe to do kfree(t) because bpf_timer_cb() read everything it needed
          * from 't'. The bpf subprog callback_fn won't be able to access 't',
          * since async->cb = NULL was already done. The timer will be
          * effectively cancelled because bpf_timer_cb() will return
          * HRTIMER_NORESTART.
          *
          * However, it is possible the timer callback_fn calling us armed the
          * timer _before_ calling us, such that failing to cancel it here will
          * cause it to possibly use struct hrtimer after freeing bpf_hrtimer.
          * Therefore, we _need_ to cancel any outstanding timers before we do
          * kfree_rcu, even though no more timers can be armed.
          *
          * Moreover, we need to schedule work even if timer does not belong to
          * the calling callback_fn, as on two different CPUs, we can end up in a
          * situation where both sides run in parallel, try to cancel one
          * another, and we end up waiting on both sides in hrtimer_cancel
          * without making forward progress, since timer1 depends on time2
          * callback to finish, and vice versa.
          *
          *  CPU 1 (timer1_cb)                   CPU 2 (timer2_cb)
          *  bpf_timer_cancel_and_free(timer2)   bpf_timer_cancel_and_free(timer1)
          *
          * To avoid these issues, punt to workqueue context when we are in a
          * timer callback.
          */
         if (this_cpu_read(hrtimer_running))
                 queue_work(system_unbound_wq, &t->cb.delete_work);
         else
                 bpf_timer_delete_work(&t->cb.delete_work);
 }
 
 /* This function is called by map_delete/update_elem for individual element and
  * by ops->map_release_uref when the user space reference to a map reaches zero.
  */
 void bpf_wq_cancel_and_free(void *val)
 {
         struct bpf_work *work;
 
         BTF_TYPE_EMIT(struct bpf_wq);
 
         work = (struct bpf_work *)__bpf_async_cancel_and_free(val);
         if (!work)
                 return;
         /* Trigger cancel of the sleepable work, but *do not* wait for
          * it to finish if it was running as we might not be in a
          * sleepable context.
          * kfree will be called once the work has finished.
          */
         schedule_work(&work->delete_work);
 }
 
 BPF_CALL_2(bpf_kptr_xchg, void *, map_value, void *, ptr)
 {
         unsigned long *kptr = map_value;
 
         /* This helper may be inlined by verifier. */
         return xchg(kptr, (unsigned long)ptr);
 }
 
 /* Unlike other PTR_TO_BTF_ID helpers the btf_id in bpf_kptr_xchg()
  * helper is determined dynamically by the verifier. Use BPF_PTR_POISON to
  * denote type that verifier will determine.
  */
 static const struct bpf_func_proto bpf_kptr_xchg_proto = {
         .func         = bpf_kptr_xchg,
         .gpl_only     = false,
         .ret_type     = RET_PTR_TO_BTF_ID_OR_NULL,
         .ret_btf_id   = BPF_PTR_POISON,
         .arg1_type    = ARG_PTR_TO_KPTR,
         .arg2_type    = ARG_PTR_TO_BTF_ID_OR_NULL | OBJ_RELEASE,
         .arg2_btf_id  = BPF_PTR_POISON,
 };
 
 /* Since the upper 8 bits of dynptr->size is reserved, the
  * maximum supported size is 2^24 - 1.
  */
 #define DYNPTR_MAX_SIZE ((1UL << 24) - 1)
 #define DYNPTR_TYPE_SHIFT       28
 #define DYNPTR_SIZE_MASK        0xFFFFFF
 #define DYNPTR_RDONLY_BIT       BIT(31)
 
 bool __bpf_dynptr_is_rdonly(const struct bpf_dynptr_kern *ptr)
 {
         return ptr->size & DYNPTR_RDONLY_BIT;
 }
 
 void bpf_dynptr_set_rdonly(struct bpf_dynptr_kern *ptr)
 {
         ptr->size |= DYNPTR_RDONLY_BIT;
 }
 
 static void bpf_dynptr_set_type(struct bpf_dynptr_kern *ptr, enum bpf_dynptr_type type)
 {
         ptr->size |= type << DYNPTR_TYPE_SHIFT;
 }
 
 static enum bpf_dynptr_type bpf_dynptr_get_type(const struct bpf_dynptr_kern *ptr)
 {
         return (ptr->size & ~(DYNPTR_RDONLY_BIT)) >> DYNPTR_TYPE_SHIFT;
 }
 
 u32 __bpf_dynptr_size(const struct bpf_dynptr_kern *ptr)
 {
         return ptr->size & DYNPTR_SIZE_MASK;
 }
 
 static void bpf_dynptr_set_size(struct bpf_dynptr_kern *ptr, u32 new_size)
 {
         u32 metadata = ptr->size & ~DYNPTR_SIZE_MASK;
 
         ptr->size = new_size | metadata;
 }
 
 int bpf_dynptr_check_size(u32 size)
 {
         return size > DYNPTR_MAX_SIZE ? -E2BIG : 0;
 }
 
 void bpf_dynptr_init(struct bpf_dynptr_kern *ptr, void *data,
                      enum bpf_dynptr_type type, u32 offset, u32 size)
 {
         ptr->data = data;
         ptr->offset = offset;
         ptr->size = size;
         bpf_dynptr_set_type(ptr, type);
 }
 
 void bpf_dynptr_set_null(struct bpf_dynptr_kern *ptr)
 {
         memset(ptr, 0, sizeof(*ptr));
 }
 
 static int bpf_dynptr_check_off_len(const struct bpf_dynptr_kern *ptr, u32 offset, u32 len)
 {
         u32 size = __bpf_dynptr_size(ptr);
 
         if (len > size || offset > size - len)
                 return -E2BIG;
 
         return 0;
 }
 
 BPF_CALL_4(bpf_dynptr_from_mem, void *, data, u32, size, u64, flags, struct bpf_dynptr_kern *, ptr)
 {
         int err;
 
         BTF_TYPE_EMIT(struct bpf_dynptr);
 
         err = bpf_dynptr_check_size(size);
         if (err)
                 goto error;
 
         /* flags is currently unsupported */
         if (flags) {
                 err = -EINVAL;
                 goto error;
         }
 
         bpf_dynptr_init(ptr, data, BPF_DYNPTR_TYPE_LOCAL, 0, size);
 
         return 0;
 
 error:
         bpf_dynptr_set_null(ptr);
         return err;
 }
 
 static const struct bpf_func_proto bpf_dynptr_from_mem_proto = {
         .func           = bpf_dynptr_from_mem,
         .gpl_only       = false,
         .ret_type       = RET_INTEGER,
         .arg1_type      = ARG_PTR_TO_UNINIT_MEM,
         .arg2_type      = ARG_CONST_SIZE_OR_ZERO,
         .arg3_type      = ARG_ANYTHING,
         .arg4_type      = ARG_PTR_TO_DYNPTR | DYNPTR_TYPE_LOCAL | MEM_UNINIT,
 };
 
 BPF_CALL_5(bpf_dynptr_read, void *, dst, u32, len, const struct bpf_dynptr_kern *, src,
            u32, offset, u64, flags)
 {
         enum bpf_dynptr_type type;
         int err;
 
         if (!src->data || flags)
                 return -EINVAL;
 
         err = bpf_dynptr_check_off_len(src, offset, len);
         if (err)
                 return err;
 
         type = bpf_dynptr_get_type(src);
 
         switch (type) {
         case BPF_DYNPTR_TYPE_LOCAL:
         case BPF_DYNPTR_TYPE_RINGBUF:
                 /* Source and destination may possibly overlap, hence use memmove to
                  * copy the data. E.g. bpf_dynptr_from_mem may create two dynptr
                  * pointing to overlapping PTR_TO_MAP_VALUE regions.
                  */
                 memmove(dst, src->data + src->offset + offset, len);
                 return 0;
         case BPF_DYNPTR_TYPE_SKB:
                 return __bpf_skb_load_bytes(src->data, src->offset + offset, dst, len);
         case BPF_DYNPTR_TYPE_XDP:
                 return __bpf_xdp_load_bytes(src->data, src->offset + offset, dst, len);
         default:
                 WARN_ONCE(true, "bpf_dynptr_read: unknown dynptr type %d\n", type);
                 return -EFAULT;
         }
 }
 
 static const struct bpf_func_proto bpf_dynptr_read_proto = {
         .func           = bpf_dynptr_read,
         .gpl_only       = false,
         .ret_type       = RET_INTEGER,
         .arg1_type      = ARG_PTR_TO_UNINIT_MEM,
         .arg2_type      = ARG_CONST_SIZE_OR_ZERO,
         .arg3_type      = ARG_PTR_TO_DYNPTR | MEM_RDONLY,
         .arg4_type      = ARG_ANYTHING,
         .arg5_type      = ARG_ANYTHING,
 };
 
 BPF_CALL_5(bpf_dynptr_write, const struct bpf_dynptr_kern *, dst, u32, offset, void *, src,
            u32, len, u64, flags)
 {
         enum bpf_dynptr_type type;
         int err;
 
         if (!dst->data || __bpf_dynptr_is_rdonly(dst))
                 return -EINVAL;
 
         err = bpf_dynptr_check_off_len(dst, offset, len);
         if (err)
                 return err;
 
         type = bpf_dynptr_get_type(dst);
 
         switch (type) {
         case BPF_DYNPTR_TYPE_LOCAL:
         case BPF_DYNPTR_TYPE_RINGBUF:
                 if (flags)
                         return -EINVAL;
                 /* Source and destination may possibly overlap, hence use memmove to
                  * copy the data. E.g. bpf_dynptr_from_mem may create two dynptr
                  * pointing to overlapping PTR_TO_MAP_VALUE regions.
                  */
                 memmove(dst->data + dst->offset + offset, src, len);
                 return 0;
         case BPF_DYNPTR_TYPE_SKB:
                 return __bpf_skb_store_bytes(dst->data, dst->offset + offset, src, len,
                                              flags);
         case BPF_DYNPTR_TYPE_XDP:
                 if (flags)
                         return -EINVAL;
                 return __bpf_xdp_store_bytes(dst->data, dst->offset + offset, src, len);
         default:
                 WARN_ONCE(true, "bpf_dynptr_write: unknown dynptr type %d\n", type);
                 return -EFAULT;
         }
 }
 
 static const struct bpf_func_proto bpf_dynptr_write_proto = {
         .func           = bpf_dynptr_write,
         .gpl_only       = false,
         .ret_type       = RET_INTEGER,
         .arg1_type      = ARG_PTR_TO_DYNPTR | MEM_RDONLY,
         .arg2_type      = ARG_ANYTHING,
         .arg3_type      = ARG_PTR_TO_MEM | MEM_RDONLY,
         .arg4_type      = ARG_CONST_SIZE_OR_ZERO,
         .arg5_type      = ARG_ANYTHING,
 };
 
 BPF_CALL_3(bpf_dynptr_data, const struct bpf_dynptr_kern *, ptr, u32, offset, u32, len)
 {
         enum bpf_dynptr_type type;
         int err;
 
         if (!ptr->data)
                 return 0;
 
         err = bpf_dynptr_check_off_len(ptr, offset, len);
         if (err)
                 return 0;
 
         if (__bpf_dynptr_is_rdonly(ptr))
                 return 0;
 
         type = bpf_dynptr_get_type(ptr);
 
         switch (type) {
         case BPF_DYNPTR_TYPE_LOCAL:
         case BPF_DYNPTR_TYPE_RINGBUF:
                 return (unsigned long)(ptr->data + ptr->offset + offset);
         case BPF_DYNPTR_TYPE_SKB:
         case BPF_DYNPTR_TYPE_XDP:
                 /* skb and xdp dynptrs should use bpf_dynptr_slice / bpf_dynptr_slice_rdwr */
                 return 0;
         default:
                 WARN_ONCE(true, "bpf_dynptr_data: unknown dynptr type %d\n", type);
                 return 0;
         }
 }
 
 static const struct bpf_func_proto bpf_dynptr_data_proto = {
         .func           = bpf_dynptr_data,
         .gpl_only       = false,
         .ret_type       = RET_PTR_TO_DYNPTR_MEM_OR_NULL,
         .arg1_type      = ARG_PTR_TO_DYNPTR | MEM_RDONLY,
         .arg2_type      = ARG_ANYTHING,
         .arg3_type      = ARG_CONST_ALLOC_SIZE_OR_ZERO,
 };
 
 const struct bpf_func_proto bpf_get_current_task_proto __weak;
 const struct bpf_func_proto bpf_get_current_task_btf_proto __weak;
 const struct bpf_func_proto bpf_probe_read_user_proto __weak;
 const struct bpf_func_proto bpf_probe_read_user_str_proto __weak;
 const struct bpf_func_proto bpf_probe_read_kernel_proto __weak;
 const struct bpf_func_proto bpf_probe_read_kernel_str_proto __weak;
 const struct bpf_func_proto bpf_task_pt_regs_proto __weak;
 
 const struct bpf_func_proto *
 bpf_base_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
 {
         switch (func_id) {
         case BPF_FUNC_map_lookup_elem:
                 return &bpf_map_lookup_elem_proto;
         case BPF_FUNC_map_update_elem:
                 return &bpf_map_update_elem_proto;
         case BPF_FUNC_map_delete_elem:
                 return &bpf_map_delete_elem_proto;
         case BPF_FUNC_map_push_elem:
                 return &bpf_map_push_elem_proto;
         case BPF_FUNC_map_pop_elem:
                 return &bpf_map_pop_elem_proto;
         case BPF_FUNC_map_peek_elem:
                 return &bpf_map_peek_elem_proto;
         case BPF_FUNC_map_lookup_percpu_elem:
                 return &bpf_map_lookup_percpu_elem_proto;
         case BPF_FUNC_get_prandom_u32:
                 return &bpf_get_prandom_u32_proto;
         case BPF_FUNC_get_smp_processor_id:
                 return &bpf_get_raw_smp_processor_id_proto;
         case BPF_FUNC_get_numa_node_id:
                 return &bpf_get_numa_node_id_proto;
         case BPF_FUNC_tail_call:
                 return &bpf_tail_call_proto;
         case BPF_FUNC_ktime_get_ns:
                 return &bpf_ktime_get_ns_proto;
         case BPF_FUNC_ktime_get_boot_ns:
                 return &bpf_ktime_get_boot_ns_proto;
         case BPF_FUNC_ktime_get_tai_ns:
                 return &bpf_ktime_get_tai_ns_proto;
         case BPF_FUNC_ringbuf_output:
                 return &bpf_ringbuf_output_proto;
         case BPF_FUNC_ringbuf_reserve:
                 return &bpf_ringbuf_reserve_proto;
         case BPF_FUNC_ringbuf_submit:
                 return &bpf_ringbuf_submit_proto;
         case BPF_FUNC_ringbuf_discard:
                 return &bpf_ringbuf_discard_proto;
         case BPF_FUNC_ringbuf_query:
                 return &bpf_ringbuf_query_proto;
         case BPF_FUNC_strncmp:
                 return &bpf_strncmp_proto;
         case BPF_FUNC_strtol:
                 return &bpf_strtol_proto;
         case BPF_FUNC_strtoul:
                 return &bpf_strtoul_proto;
         case BPF_FUNC_get_current_pid_tgid:
                 return &bpf_get_current_pid_tgid_proto;
         case BPF_FUNC_get_ns_current_pid_tgid:
                 return &bpf_get_ns_current_pid_tgid_proto;
         default:
                 break;
         }
 
         if (!bpf_token_capable(prog->aux->token, CAP_BPF))
                 return NULL;
 
         switch (func_id) {
         case BPF_FUNC_spin_lock:
                 return &bpf_spin_lock_proto;
         case BPF_FUNC_spin_unlock:
                 return &bpf_spin_unlock_proto;
         case BPF_FUNC_jiffies64:
                 return &bpf_jiffies64_proto;
         case BPF_FUNC_per_cpu_ptr:
                 return &bpf_per_cpu_ptr_proto;
         case BPF_FUNC_this_cpu_ptr:
                 return &bpf_this_cpu_ptr_proto;
         case BPF_FUNC_timer_init:
                 return &bpf_timer_init_proto;
         case BPF_FUNC_timer_set_callback:
                 return &bpf_timer_set_callback_proto;
         case BPF_FUNC_timer_start:
                 return &bpf_timer_start_proto;
         case BPF_FUNC_timer_cancel:
                 return &bpf_timer_cancel_proto;
         case BPF_FUNC_kptr_xchg:
                 return &bpf_kptr_xchg_proto;
         case BPF_FUNC_for_each_map_elem:
                 return &bpf_for_each_map_elem_proto;
         case BPF_FUNC_loop:
                 return &bpf_loop_proto;
         case BPF_FUNC_user_ringbuf_drain:
                 return &bpf_user_ringbuf_drain_proto;
         case BPF_FUNC_ringbuf_reserve_dynptr:
                 return &bpf_ringbuf_reserve_dynptr_proto;
         case BPF_FUNC_ringbuf_submit_dynptr:
                 return &bpf_ringbuf_submit_dynptr_proto;
         case BPF_FUNC_ringbuf_discard_dynptr:
                 return &bpf_ringbuf_discard_dynptr_proto;
         case BPF_FUNC_dynptr_from_mem:
                 return &bpf_dynptr_from_mem_proto;
         case BPF_FUNC_dynptr_read:
                 return &bpf_dynptr_read_proto;
         case BPF_FUNC_dynptr_write:
                 return &bpf_dynptr_write_proto;
         case BPF_FUNC_dynptr_data:
                 return &bpf_dynptr_data_proto;
 #ifdef CONFIG_CGROUPS
         case BPF_FUNC_cgrp_storage_get:
                 return &bpf_cgrp_storage_get_proto;
         case BPF_FUNC_cgrp_storage_delete:
                 return &bpf_cgrp_storage_delete_proto;
         case BPF_FUNC_get_current_cgroup_id:
                 return &bpf_get_current_cgroup_id_proto;
         case BPF_FUNC_get_current_ancestor_cgroup_id:
                 return &bpf_get_current_ancestor_cgroup_id_proto;
 #endif
         default:
                 break;
         }
 
         if (!bpf_token_capable(prog->aux->token, CAP_PERFMON))
                 return NULL;
 
         switch (func_id) {
         case BPF_FUNC_trace_printk:
                 return bpf_get_trace_printk_proto();
         case BPF_FUNC_get_current_task:
                 return &bpf_get_current_task_proto;
         case BPF_FUNC_get_current_task_btf:
                 return &bpf_get_current_task_btf_proto;
         case BPF_FUNC_probe_read_user:
                 return &bpf_probe_read_user_proto;
         case BPF_FUNC_probe_read_kernel:
                 return security_locked_down(LOCKDOWN_BPF_READ_KERNEL) < 0 ?
                        NULL : &bpf_probe_read_kernel_proto;
         case BPF_FUNC_probe_read_user_str:
                 return &bpf_probe_read_user_str_proto;
         case BPF_FUNC_probe_read_kernel_str:
                 return security_locked_down(LOCKDOWN_BPF_READ_KERNEL) < 0 ?
                        NULL : &bpf_probe_read_kernel_str_proto;
         case BPF_FUNC_snprintf_btf:
                 return &bpf_snprintf_btf_proto;
         case BPF_FUNC_snprintf:
                 return &bpf_snprintf_proto;
         case BPF_FUNC_task_pt_regs:
                 return &bpf_task_pt_regs_proto;
         case BPF_FUNC_trace_vprintk:
                 return bpf_get_trace_vprintk_proto();
         default:
                 return NULL;
         }
 }
 
 void bpf_list_head_free(const struct btf_field *field, void *list_head,
                         struct bpf_spin_lock *spin_lock)
 {
         struct list_head *head = list_head, *orig_head = list_head;
 
         BUILD_BUG_ON(sizeof(struct list_head) > sizeof(struct bpf_list_head));
         BUILD_BUG_ON(__alignof__(struct list_head) > __alignof__(struct bpf_list_head));
 
         /* Do the actual list draining outside the lock to not hold the lock for
          * too long, and also prevent deadlocks if tracing programs end up
          * executing on entry/exit of functions called inside the critical
          * section, and end up doing map ops that call bpf_list_head_free for
          * the same map value again.
          */
         __bpf_spin_lock_irqsave(spin_lock);
         if (!head->next || list_empty(head))
                 goto unlock;
         head = head->next;
 unlock:
         INIT_LIST_HEAD(orig_head);
         __bpf_spin_unlock_irqrestore(spin_lock);
 
         while (head != orig_head) {
                 void *obj = head;
 
                 obj -= field->graph_root.node_offset;
                 head = head->next;
                 /* The contained type can also have resources, including a
                  * bpf_list_head which needs to be freed.
                  */
                 migrate_disable();
                 __bpf_obj_drop_impl(obj, field->graph_root.value_rec, false);
                 migrate_enable();
         }
 }
 
 /* Like rbtree_postorder_for_each_entry_safe, but 'pos' and 'n' are
  * 'rb_node *', so field name of rb_node within containing struct is not
  * needed.
  *
  * Since bpf_rb_tree's node type has a corresponding struct btf_field with
  * graph_root.node_offset, it's not necessary to know field name
  * or type of node struct
  */
 #define bpf_rbtree_postorder_for_each_entry_safe(pos, n, root) \
         for (pos = rb_first_postorder(root); \
             pos && ({ n = rb_next_postorder(pos); 1; }); \
             pos = n)
 
 void bpf_rb_root_free(const struct btf_field *field, void *rb_root,
                       struct bpf_spin_lock *spin_lock)
 {
         struct rb_root_cached orig_root, *root = rb_root;
         struct rb_node *pos, *n;
         void *obj;
 
         BUILD_BUG_ON(sizeof(struct rb_root_cached) > sizeof(struct bpf_rb_root));
         BUILD_BUG_ON(__alignof__(struct rb_root_cached) > __alignof__(struct bpf_rb_root));
 
         __bpf_spin_lock_irqsave(spin_lock);
         orig_root = *root;
         *root = RB_ROOT_CACHED;
         __bpf_spin_unlock_irqrestore(spin_lock);
 
         bpf_rbtree_postorder_for_each_entry_safe(pos, n, &orig_root.rb_root) {
                 obj = pos;
                 obj -= field->graph_root.node_offset;
 
 
                 migrate_disable();
                 __bpf_obj_drop_impl(obj, field->graph_root.value_rec, false);
                 migrate_enable();
         }
 }
 
 __bpf_kfunc_start_defs();
 
 __bpf_kfunc void *bpf_obj_new_impl(u64 local_type_id__k, void *meta__ign)
 {
         struct btf_struct_meta *meta = meta__ign;
         u64 size = local_type_id__k;
         void *p;
 
         p = bpf_mem_alloc(&bpf_global_ma, size);
         if (!p)
                 return NULL;
         if (meta)
                 bpf_obj_init(meta->record, p);
         return p;
 }
 
 __bpf_kfunc void *bpf_percpu_obj_new_impl(u64 local_type_id__k, void *meta__ign)
 {
         u64 size = local_type_id__k;
 
         /* The verifier has ensured that meta__ign must be NULL */
         return bpf_mem_alloc(&bpf_global_percpu_ma, size);
 }
 
 /* Must be called under migrate_disable(), as required by bpf_mem_free */
 void __bpf_obj_drop_impl(void *p, const struct btf_record *rec, bool percpu)
 {
         struct bpf_mem_alloc *ma;
 
         if (rec && rec->refcount_off >= 0 &&
             !refcount_dec_and_test((refcount_t *)(p + rec->refcount_off))) {
                 /* Object is refcounted and refcount_dec didn't result in 0
                  * refcount. Return without freeing the object
                  */
                 return;
         }
 
         if (rec)
                 bpf_obj_free_fields(rec, p);
 
         if (percpu)
                 ma = &bpf_global_percpu_ma;
         else
                 ma = &bpf_global_ma;
         bpf_mem_free_rcu(ma, p);
 }
 
 __bpf_kfunc void bpf_obj_drop_impl(void *p__alloc, void *meta__ign)
 {
         struct btf_struct_meta *meta = meta__ign;
         void *p = p__alloc;
 
         __bpf_obj_drop_impl(p, meta ? meta->record : NULL, false);
 }
 
 __bpf_kfunc void bpf_percpu_obj_drop_impl(void *p__alloc, void *meta__ign)
 {
         /* The verifier has ensured that meta__ign must be NULL */
         bpf_mem_free_rcu(&bpf_global_percpu_ma, p__alloc);
 }
 
 __bpf_kfunc void *bpf_refcount_acquire_impl(void *p__refcounted_kptr, void *meta__ign)
 {
         struct btf_struct_meta *meta = meta__ign;
         struct bpf_refcount *ref;
 
         /* Could just cast directly to refcount_t *, but need some code using
          * bpf_refcount type so that it is emitted in vmlinux BTF
          */
         ref = (struct bpf_refcount *)(p__refcounted_kptr + meta->record->refcount_off);
         if (!refcount_inc_not_zero((refcount_t *)ref))
                 return NULL;
 
         /* Verifier strips KF_RET_NULL if input is owned ref, see is_kfunc_ret_null
          * in verifier.c
          */
         return (void *)p__refcounted_kptr;
 }
 
 static int __bpf_list_add(struct bpf_list_node_kern *node,
                           struct bpf_list_head *head,
                           bool tail, struct btf_record *rec, u64 off)
 {
         struct list_head *n = &node->list_head, *h = (void *)head;
 
         /* If list_head was 0-initialized by map, bpf_obj_init_field wasn't
          * called on its fields, so init here
          */
         if (unlikely(!h->next))
                 INIT_LIST_HEAD(h);
 
         /* node->owner != NULL implies !list_empty(n), no need to separately
          * check the latter
          */
         if (cmpxchg(&node->owner, NULL, BPF_PTR_POISON)) {
                 /* Only called from BPF prog, no need to migrate_disable */
                 __bpf_obj_drop_impl((void *)n - off, rec, false);
                 return -EINVAL;
         }
 
         tail ? list_add_tail(n, h) : list_add(n, h);
         WRITE_ONCE(node->owner, head);
 
         return 0;
 }
 
 __bpf_kfunc int bpf_list_push_front_impl(struct bpf_list_head *head,
                                          struct bpf_list_node *node,
                                          void *meta__ign, u64 off)
 {
         struct bpf_list_node_kern *n = (void *)node;
         struct btf_struct_meta *meta = meta__ign;
 
         return __bpf_list_add(n, head, false, meta ? meta->record : NULL, off);
 }
 
 __bpf_kfunc int bpf_list_push_back_impl(struct bpf_list_head *head,
                                         struct bpf_list_node *node,
                                         void *meta__ign, u64 off)
 {
         struct bpf_list_node_kern *n = (void *)node;
         struct btf_struct_meta *meta = meta__ign;
 
         return __bpf_list_add(n, head, true, meta ? meta->record : NULL, off);
 }
 
 static struct bpf_list_node *__bpf_list_del(struct bpf_list_head *head, bool tail)
 {
         struct list_head *n, *h = (void *)head;
         struct bpf_list_node_kern *node;
 
         /* If list_head was 0-initialized by map, bpf_obj_init_field wasn't
          * called on its fields, so init here
          */
         if (unlikely(!h->next))
                 INIT_LIST_HEAD(h);
         if (list_empty(h))
                 return NULL;
 
         n = tail ? h->prev : h->next;
         node = container_of(n, struct bpf_list_node_kern, list_head);
         if (WARN_ON_ONCE(READ_ONCE(node->owner) != head))
                 return NULL;
 
         list_del_init(n);
         WRITE_ONCE(node->owner, NULL);
         return (struct bpf_list_node *)n;
 }
 
 __bpf_kfunc struct bpf_list_node *bpf_list_pop_front(struct bpf_list_head *head)
 {
         return __bpf_list_del(head, false);
 }
 
 __bpf_kfunc struct bpf_list_node *bpf_list_pop_back(struct bpf_list_head *head)
 {
         return __bpf_list_del(head, true);
 }
 
 __bpf_kfunc struct bpf_rb_node *bpf_rbtree_remove(struct bpf_rb_root *root,
                                                   struct bpf_rb_node *node)
 {
         struct bpf_rb_node_kern *node_internal = (struct bpf_rb_node_kern *)node;
         struct rb_root_cached *r = (struct rb_root_cached *)root;
         struct rb_node *n = &node_internal->rb_node;
 
         /* node_internal->owner != root implies either RB_EMPTY_NODE(n) or
          * n is owned by some other tree. No need to check RB_EMPTY_NODE(n)
          */
         if (READ_ONCE(node_internal->owner) != root)
                 return NULL;
 
         rb_erase_cached(n, r);
         RB_CLEAR_NODE(n);
         WRITE_ONCE(node_internal->owner, NULL);
         return (struct bpf_rb_node *)n;
 }
 
 /* Need to copy rbtree_add_cached's logic here because our 'less' is a BPF
  * program
  */
 static int __bpf_rbtree_add(struct bpf_rb_root *root,
                             struct bpf_rb_node_kern *node,
                             void *less, struct btf_record *rec, u64 off)
 {
         struct rb_node **link = &((struct rb_root_cached *)root)->rb_root.rb_node;
         struct rb_node *parent = NULL, *n = &node->rb_node;
         bpf_callback_t cb = (bpf_callback_t)less;
         bool leftmost = true;
 
         /* node->owner != NULL implies !RB_EMPTY_NODE(n), no need to separately
          * check the latter
          */
         if (cmpxchg(&node->owner, NULL, BPF_PTR_POISON)) {
                 /* Only called from BPF prog, no need to migrate_disable */
                 __bpf_obj_drop_impl((void *)n - off, rec, false);
                 return -EINVAL;
         }
 
         while (*link) {
                 parent = *link;
                 if (cb((uintptr_t)node, (uintptr_t)parent, 0, 0, 0)) {
                         link = &parent->rb_left;
                 } else {
                         link = &parent->rb_right;
                         leftmost = false;
                 }
         }
 
         rb_link_node(n, parent, link);
         rb_insert_color_cached(n, (struct rb_root_cached *)root, leftmost);
         WRITE_ONCE(node->owner, root);
         return 0;
 }
 
 __bpf_kfunc int bpf_rbtree_add_impl(struct bpf_rb_root *root, struct bpf_rb_node *node,
                                     bool (less)(struct bpf_rb_node *a, const struct bpf_rb_node *b),
                                     void *meta__ign, u64 off)
 {
         struct btf_struct_meta *meta = meta__ign;
         struct bpf_rb_node_kern *n = (void *)node;
 
         return __bpf_rbtree_add(root, n, (void *)less, meta ? meta->record : NULL, off);
 }
 
 __bpf_kfunc struct bpf_rb_node *bpf_rbtree_first(struct bpf_rb_root *root)
 {
         struct rb_root_cached *r = (struct rb_root_cached *)root;
 
         return (struct bpf_rb_node *)rb_first_cached(r);
 }
 
 /**
  * bpf_task_acquire - Acquire a reference to a task. A task acquired by this
  * kfunc which is not stored in a map as a kptr, must be released by calling
  * bpf_task_release().
  * @p: The task on which a reference is being acquired.
  */
 __bpf_kfunc struct task_struct *bpf_task_acquire(struct task_struct *p)
 {
         if (refcount_inc_not_zero(&p->rcu_users))
                 return p;
         return NULL;
 }
 
 /**
  * bpf_task_release - Release the reference acquired on a task.
  * @p: The task on which a reference is being released.
  */
 __bpf_kfunc void bpf_task_release(struct task_struct *p)
 {
         put_task_struct_rcu_user(p);
 }
 
 __bpf_kfunc void bpf_task_release_dtor(void *p)
 {
         put_task_struct_rcu_user(p);
 }
 CFI_NOSEAL(bpf_task_release_dtor);
 
 #ifdef CONFIG_CGROUPS
 /**
  * bpf_cgroup_acquire - Acquire a reference to a cgroup. A cgroup acquired by
  * this kfunc which is not stored in a map as a kptr, must be released by
  * calling bpf_cgroup_release().
  * @cgrp: The cgroup on which a reference is being acquired.
  */
 __bpf_kfunc struct cgroup *bpf_cgroup_acquire(struct cgroup *cgrp)
 {
         return cgroup_tryget(cgrp) ? cgrp : NULL;
 }
 
 /**
  * bpf_cgroup_release - Release the reference acquired on a cgroup.
  * If this kfunc is invoked in an RCU read region, the cgroup is guaranteed to
  * not be freed until the current grace period has ended, even if its refcount
  * drops to 0.
  * @cgrp: The cgroup on which a reference is being released.
  */
 __bpf_kfunc void bpf_cgroup_release(struct cgroup *cgrp)
 {
         cgroup_put(cgrp);
 }
 
 __bpf_kfunc void bpf_cgroup_release_dtor(void *cgrp)
 {
         cgroup_put(cgrp);
 }
 CFI_NOSEAL(bpf_cgroup_release_dtor);
 
 /**
  * bpf_cgroup_ancestor - Perform a lookup on an entry in a cgroup's ancestor
  * array. A cgroup returned by this kfunc which is not subsequently stored in a
  * map, must be released by calling bpf_cgroup_release().
  * @cgrp: The cgroup for which we're performing a lookup.
  * @level: The level of ancestor to look up.
  */
 __bpf_kfunc struct cgroup *bpf_cgroup_ancestor(struct cgroup *cgrp, int level)
 {
         struct cgroup *ancestor;
 
         if (level > cgrp->level || level < 0)
                 return NULL;
 
         /* cgrp's refcnt could be 0 here, but ancestors can still be accessed */
         ancestor = cgrp->ancestors[level];
         if (!cgroup_tryget(ancestor))
                 return NULL;
         return ancestor;
 }
 
 /**
  * bpf_cgroup_from_id - Find a cgroup from its ID. A cgroup returned by this
  * kfunc which is not subsequently stored in a map, must be released by calling
  * bpf_cgroup_release().
  * @cgid: cgroup id.
  */
 __bpf_kfunc struct cgroup *bpf_cgroup_from_id(u64 cgid)
 {
         struct cgroup *cgrp;
 
         cgrp = cgroup_get_from_id(cgid);
         if (IS_ERR(cgrp))
                 return NULL;
         return cgrp;
 }
 
 /**
  * bpf_task_under_cgroup - wrap task_under_cgroup_hierarchy() as a kfunc, test
  * task's membership of cgroup ancestry.
  * @task: the task to be tested
  * @ancestor: possible ancestor of @task's cgroup
  *
  * Tests whether @task's default cgroup hierarchy is a descendant of @ancestor.
  * It follows all the same rules as cgroup_is_descendant, and only applies
  * to the default hierarchy.
  */
 __bpf_kfunc long bpf_task_under_cgroup(struct task_struct *task,
                                        struct cgroup *ancestor)
 {
         long ret;
 
         rcu_read_lock();
         ret = task_under_cgroup_hierarchy(task, ancestor);
         rcu_read_unlock();
         return ret;
 }
 
 /**
  * bpf_task_get_cgroup1 - Acquires the associated cgroup of a task within a
  * specific cgroup1 hierarchy. The cgroup1 hierarchy is identified by its
  * hierarchy ID.
  * @task: The target task
  * @hierarchy_id: The ID of a cgroup1 hierarchy
  *
  * On success, the cgroup is returen. On failure, NULL is returned.
  */
 __bpf_kfunc struct cgroup *
 bpf_task_get_cgroup1(struct task_struct *task, int hierarchy_id)
 {
         struct cgroup *cgrp = task_get_cgroup1(task, hierarchy_id);
 
         if (IS_ERR(cgrp))
                 return NULL;
         return cgrp;
 }
 #endif /* CONFIG_CGROUPS */
 
 /**
  * bpf_task_from_pid - Find a struct task_struct from its pid by looking it up
  * in the root pid namespace idr. If a task is returned, it must either be
  * stored in a map, or released with bpf_task_release().
  * @pid: The pid of the task being looked up.
  */
 __bpf_kfunc struct task_struct *bpf_task_from_pid(s32 pid)
 {
         struct task_struct *p;
 
         rcu_read_lock();
         p = find_task_by_pid_ns(pid, &init_pid_ns);
         if (p)
                 p = bpf_task_acquire(p);
         rcu_read_unlock();
 
         return p;
 }
 
 /**
  * bpf_dynptr_slice() - Obtain a read-only pointer to the dynptr data.
  * @p: The dynptr whose data slice to retrieve
  * @offset: Offset into the dynptr
  * @buffer__opt: User-provided buffer to copy contents into.  May be NULL
  * @buffer__szk: Size (in bytes) of the buffer if present. This is the
  *               length of the requested slice. This must be a constant.
  *
  * For non-skb and non-xdp type dynptrs, there is no difference between
  * bpf_dynptr_slice and bpf_dynptr_data.
  *
  *  If buffer__opt is NULL, the call will fail if buffer_opt was needed.
  *
  * If the intention is to write to the data slice, please use
  * bpf_dynptr_slice_rdwr.
  *
  * The user must check that the returned pointer is not null before using it.
  *
  * Please note that in the case of skb and xdp dynptrs, bpf_dynptr_slice
  * does not change the underlying packet data pointers, so a call to
  * bpf_dynptr_slice will not invalidate any ctx->data/data_end pointers in
  * the bpf program.
  *
  * Return: NULL if the call failed (eg invalid dynptr), pointer to a read-only
  * data slice (can be either direct pointer to the data or a pointer to the user
  * provided buffer, with its contents containing the data, if unable to obtain
  * direct pointer)
  */
 __bpf_kfunc void *bpf_dynptr_slice(const struct bpf_dynptr *p, u32 offset,
                                    void *buffer__opt, u32 buffer__szk)
 {
         const struct bpf_dynptr_kern *ptr = (struct bpf_dynptr_kern *)p;
         enum bpf_dynptr_type type;
         u32 len = buffer__szk;
         int err;
 
         if (!ptr->data)
                 return NULL;
 
         err = bpf_dynptr_check_off_len(ptr, offset, len);
         if (err)
                 return NULL;
 
         type = bpf_dynptr_get_type(ptr);
 
         switch (type) {
         case BPF_DYNPTR_TYPE_LOCAL:
         case BPF_DYNPTR_TYPE_RINGBUF:
                 return ptr->data + ptr->offset + offset;
         case BPF_DYNPTR_TYPE_SKB:
                 if (buffer__opt)
                         return skb_header_pointer(ptr->data, ptr->offset + offset, len, buffer__opt);
                 else
                         return skb_pointer_if_linear(ptr->data, ptr->offset + offset, len);
         case BPF_DYNPTR_TYPE_XDP:
         {
                 void *xdp_ptr = bpf_xdp_pointer(ptr->data, ptr->offset + offset, len);
                 if (!IS_ERR_OR_NULL(xdp_ptr))
                         return xdp_ptr;
 
                 if (!buffer__opt)
                         return NULL;
                 bpf_xdp_copy_buf(ptr->data, ptr->offset + offset, buffer__opt, len, false);
                 return buffer__opt;
         }
         default:
                 WARN_ONCE(true, "unknown dynptr type %d\n", type);
                 return NULL;
         }
 }
 
 /**
  * bpf_dynptr_slice_rdwr() - Obtain a writable pointer to the dynptr data.
  * @p: The dynptr whose data slice to retrieve
  * @offset: Offset into the dynptr
  * @buffer__opt: User-provided buffer to copy contents into. May be NULL
  * @buffer__szk: Size (in bytes) of the buffer if present. This is the
  *               length of the requested slice. This must be a constant.
  *
  * For non-skb and non-xdp type dynptrs, there is no difference between
  * bpf_dynptr_slice and bpf_dynptr_data.
  *
  * If buffer__opt is NULL, the call will fail if buffer_opt was needed.
  *
  * The returned pointer is writable and may point to either directly the dynptr
  * data at the requested offset or to the buffer if unable to obtain a direct
  * data pointer to (example: the requested slice is to the paged area of an skb
  * packet). In the case where the returned pointer is to the buffer, the user
  * is responsible for persisting writes through calling bpf_dynptr_write(). This
  * usually looks something like this pattern:
  *
  * struct eth_hdr *eth = bpf_dynptr_slice_rdwr(&dynptr, 0, buffer, sizeof(buffer));
  * if (!eth)
  *      return TC_ACT_SHOT;
  *
  * // mutate eth header //
  *
  * if (eth == buffer)
  *      bpf_dynptr_write(&ptr, 0, buffer, sizeof(buffer), 0);
  *
  * Please note that, as in the example above, the user must check that the
  * returned pointer is not null before using it.
  *
  * Please also note that in the case of skb and xdp dynptrs, bpf_dynptr_slice_rdwr
  * does not change the underlying packet data pointers, so a call to
  * bpf_dynptr_slice_rdwr will not invalidate any ctx->data/data_end pointers in
  * the bpf program.
  *
  * Return: NULL if the call failed (eg invalid dynptr), pointer to a
  * data slice (can be either direct pointer to the data or a pointer to the user
  * provided buffer, with its contents containing the data, if unable to obtain
  * direct pointer)
  */
 __bpf_kfunc void *bpf_dynptr_slice_rdwr(const struct bpf_dynptr *p, u32 offset,
                                         void *buffer__opt, u32 buffer__szk)
 {
         const struct bpf_dynptr_kern *ptr = (struct bpf_dynptr_kern *)p;
 
         if (!ptr->data || __bpf_dynptr_is_rdonly(ptr))
                 return NULL;
 
         /* bpf_dynptr_slice_rdwr is the same logic as bpf_dynptr_slice.
          *
          * For skb-type dynptrs, it is safe to write into the returned pointer
          * if the bpf program allows skb data writes. There are two possibilities
          * that may occur when calling bpf_dynptr_slice_rdwr:
          *
          * 1) The requested slice is in the head of the skb. In this case, the
          * returned pointer is directly to skb data, and if the skb is cloned, the
          * verifier will have uncloned it (see bpf_unclone_prologue()) already.
          * The pointer can be directly written into.
          *
          * 2) Some portion of the requested slice is in the paged buffer area.
          * In this case, the requested data will be copied out into the buffer
          * and the returned pointer will be a pointer to the buffer. The skb
          * will not be pulled. To persist the write, the user will need to call
          * bpf_dynptr_write(), which will pull the skb and commit the write.
          *
          * Similarly for xdp programs, if the requested slice is not across xdp
          * fragments, then a direct pointer will be returned, otherwise the data
          * will be copied out into the buffer and the user will need to call
          * bpf_dynptr_write() to commit changes.
          */
         return bpf_dynptr_slice(p, offset, buffer__opt, buffer__szk);
 }
 
 __bpf_kfunc int bpf_dynptr_adjust(const struct bpf_dynptr *p, u32 start, u32 end)
 {
         struct bpf_dynptr_kern *ptr = (struct bpf_dynptr_kern *)p;
         u32 size;
 
         if (!ptr->data || start > end)
                 return -EINVAL;
 
         size = __bpf_dynptr_size(ptr);
 
         if (start > size || end > size)
                 return -ERANGE;
 
         ptr->offset += start;
         bpf_dynptr_set_size(ptr, end - start);
 
         return 0;
 }
 
 __bpf_kfunc bool bpf_dynptr_is_null(const struct bpf_dynptr *p)
 {
         struct bpf_dynptr_kern *ptr = (struct bpf_dynptr_kern *)p;
 
         return !ptr->data;
 }
 
 __bpf_kfunc bool bpf_dynptr_is_rdonly(const struct bpf_dynptr *p)
 {
         struct bpf_dynptr_kern *ptr = (struct bpf_dynptr_kern *)p;
 
         if (!ptr->data)
                 return false;
 
         return __bpf_dynptr_is_rdonly(ptr);
 }
 
 __bpf_kfunc __u32 bpf_dynptr_size(const struct bpf_dynptr *p)
 {
         struct bpf_dynptr_kern *ptr = (struct bpf_dynptr_kern *)p;
 
         if (!ptr->data)
                 return -EINVAL;
 
         return __bpf_dynptr_size(ptr);
 }
 
 __bpf_kfunc int bpf_dynptr_clone(const struct bpf_dynptr *p,
                                  struct bpf_dynptr *clone__uninit)
 {
         struct bpf_dynptr_kern *clone = (struct bpf_dynptr_kern *)clone__uninit;
         struct bpf_dynptr_kern *ptr = (struct bpf_dynptr_kern *)p;
 
         if (!ptr->data) {
                 bpf_dynptr_set_null(clone);
                 return -EINVAL;
         }
 
         *clone = *ptr;
 
         return 0;
 }
 
 __bpf_kfunc void *bpf_cast_to_kern_ctx(void *obj)
 {
         return obj;
 }
 
 __bpf_kfunc void *bpf_rdonly_cast(const void *obj__ign, u32 btf_id__k)
 {
         return (void *)obj__ign;
 }
 
 __bpf_kfunc void bpf_rcu_read_lock(void)
 {
         rcu_read_lock();
 }
 
 __bpf_kfunc void bpf_rcu_read_unlock(void)
 {
         rcu_read_unlock();
 }
 
 struct bpf_throw_ctx {
         struct bpf_prog_aux *aux;
         u64 sp;
         u64 bp;
         int cnt;
 };
 
 static bool bpf_stack_walker(void *cookie, u64 ip, u64 sp, u64 bp)
 {
         struct bpf_throw_ctx *ctx = cookie;
         struct bpf_prog *prog;
 
         if (!is_bpf_text_address(ip))
                 return !ctx->cnt;
         prog = bpf_prog_ksym_find(ip);
         ctx->cnt++;
         if (bpf_is_subprog(prog))
                 return true;
         ctx->aux = prog->aux;
         ctx->sp = sp;
         ctx->bp = bp;
         return false;
 }
 
 __bpf_kfunc void bpf_throw(u64 cookie)
 {
         struct bpf_throw_ctx ctx = {};
 
         arch_bpf_stack_walk(bpf_stack_walker, &ctx);
         WARN_ON_ONCE(!ctx.aux);
         if (ctx.aux)
                 WARN_ON_ONCE(!ctx.aux->exception_boundary);
         WARN_ON_ONCE(!ctx.bp);
         WARN_ON_ONCE(!ctx.cnt);
         /* Prevent KASAN false positives for CONFIG_KASAN_STACK by unpoisoning
          * deeper stack depths than ctx.sp as we do not return from bpf_throw,
          * which skips compiler generated instrumentation to do the same.
          */
         kasan_unpoison_task_stack_below((void *)(long)ctx.sp);
         ctx.aux->bpf_exception_cb(cookie, ctx.sp, ctx.bp, 0, 0);
         WARN(1, "A call to BPF exception callback should never return\n");
 }
 
 __bpf_kfunc int bpf_wq_init(struct bpf_wq *wq, void *p__map, unsigned int flags)
 {
         struct bpf_async_kern *async = (struct bpf_async_kern *)wq;
         struct bpf_map *map = p__map;
 
         BUILD_BUG_ON(sizeof(struct bpf_async_kern) > sizeof(struct bpf_wq));
         BUILD_BUG_ON(__alignof__(struct bpf_async_kern) != __alignof__(struct bpf_wq));
 
         if (flags)
                 return -EINVAL;
 
         return __bpf_async_init(async, map, flags, BPF_ASYNC_TYPE_WQ);
 }
 
 __bpf_kfunc int bpf_wq_start(struct bpf_wq *wq, unsigned int flags)
 {
         struct bpf_async_kern *async = (struct bpf_async_kern *)wq;
         struct bpf_work *w;
 
         if (in_nmi())
                 return -EOPNOTSUPP;
         if (flags)
                 return -EINVAL;
         w = READ_ONCE(async->work);
         if (!w || !READ_ONCE(w->cb.prog))
                 return -EINVAL;
 
         schedule_work(&w->work);
         return 0;
 }
 
 __bpf_kfunc int bpf_wq_set_callback_impl(struct bpf_wq *wq,
                                          int (callback_fn)(void *map, int *key, void *value),
                                          unsigned int flags,
                                          void *aux__ign)
 {
         struct bpf_prog_aux *aux = (struct bpf_prog_aux *)aux__ign;
         struct bpf_async_kern *async = (struct bpf_async_kern *)wq;
 
         if (flags)
                 return -EINVAL;
 
         return __bpf_async_set_callback(async, callback_fn, aux, flags, BPF_ASYNC_TYPE_WQ);
 }
 
 __bpf_kfunc void bpf_preempt_disable(void)
 {
         preempt_disable();
 }
 
 __bpf_kfunc void bpf_preempt_enable(void)
 {
         preempt_enable();
 }
 
 struct bpf_iter_bits {
         __u64 __opaque[2];
 } __aligned(8);
 
 struct bpf_iter_bits_kern {
         union {
                 unsigned long *bits;
                 unsigned long bits_copy;
         };
         u32 nr_bits;
         int bit;
 } __aligned(8);
 
 /**
  * bpf_iter_bits_new() - Initialize a new bits iterator for a given memory area
  * @it: The new bpf_iter_bits to be created
  * @unsafe_ptr__ign: A pointer pointing to a memory area to be iterated over
  * @nr_words: The size of the specified memory area, measured in 8-byte units.
  * Due to the limitation of memalloc, it can't be greater than 512.
  *
  * This function initializes a new bpf_iter_bits structure for iterating over
  * a memory area which is specified by the @unsafe_ptr__ign and @nr_words. It
  * copies the data of the memory area to the newly created bpf_iter_bits @it for
  * subsequent iteration operations.
  *
  * On success, 0 is returned. On failure, ERR is returned.
  */
 __bpf_kfunc int
 bpf_iter_bits_new(struct bpf_iter_bits *it, const u64 *unsafe_ptr__ign, u32 nr_words)
 {
         struct bpf_iter_bits_kern *kit = (void *)it;
         u32 nr_bytes = nr_words * sizeof(u64);
         u32 nr_bits = BYTES_TO_BITS(nr_bytes);
         int err;
 
         BUILD_BUG_ON(sizeof(struct bpf_iter_bits_kern) != sizeof(struct bpf_iter_bits));
         BUILD_BUG_ON(__alignof__(struct bpf_iter_bits_kern) !=
                      __alignof__(struct bpf_iter_bits));
 
         kit->nr_bits = 0;
         kit->bits_copy = 0;
         kit->bit = -1;
 
         if (!unsafe_ptr__ign || !nr_words)
                 return -EINVAL;
 
         /* Optimization for u64 mask */
         if (nr_bits == 64) {
                 err = bpf_probe_read_kernel_common(&kit->bits_copy, nr_bytes, unsafe_ptr__ign);
                 if (err)
                         return -EFAULT;
 
                 kit->nr_bits = nr_bits;
                 return 0;
         }
 
         /* Fallback to memalloc */
         kit->bits = bpf_mem_alloc(&bpf_global_ma, nr_bytes);
         if (!kit->bits)
                 return -ENOMEM;
 
         err = bpf_probe_read_kernel_common(kit->bits, nr_bytes, unsafe_ptr__ign);
         if (err) {
                 bpf_mem_free(&bpf_global_ma, kit->bits);
                 return err;
         }
 
         kit->nr_bits = nr_bits;
         return 0;
 }
 
 /**
  * bpf_iter_bits_next() - Get the next bit in a bpf_iter_bits
  * @it: The bpf_iter_bits to be checked
  *
  * This function returns a pointer to a number representing the value of the
  * next bit in the bits.
  *
  * If there are no further bits available, it returns NULL.
  */
 __bpf_kfunc int *bpf_iter_bits_next(struct bpf_iter_bits *it)
 {
         struct bpf_iter_bits_kern *kit = (void *)it;
         u32 nr_bits = kit->nr_bits;
         const unsigned long *bits;
         int bit;
 
         if (nr_bits == 0)
                 return NULL;
 
         bits = nr_bits == 64 ? &kit->bits_copy : kit->bits;
         bit = find_next_bit(bits, nr_bits, kit->bit + 1);
         if (bit >= nr_bits) {
                 kit->nr_bits = 0;
                 return NULL;
         }
 
         kit->bit = bit;
         return &kit->bit;
 }
 
 /**
  * bpf_iter_bits_destroy() - Destroy a bpf_iter_bits
  * @it: The bpf_iter_bits to be destroyed
  *
  * Destroy the resource associated with the bpf_iter_bits.
  */
 __bpf_kfunc void bpf_iter_bits_destroy(struct bpf_iter_bits *it)
 {
         struct bpf_iter_bits_kern *kit = (void *)it;
 
         if (kit->nr_bits <= 64)
                 return;
         bpf_mem_free(&bpf_global_ma, kit->bits);
 }
 
 __bpf_kfunc_end_defs();
 
 BTF_KFUNCS_START(generic_btf_ids)
 #ifdef CONFIG_CRASH_DUMP
 BTF_ID_FLAGS(func, crash_kexec, KF_DESTRUCTIVE)
 #endif
 BTF_ID_FLAGS(func, bpf_obj_new_impl, KF_ACQUIRE | KF_RET_NULL)
 BTF_ID_FLAGS(func, bpf_percpu_obj_new_impl, KF_ACQUIRE | KF_RET_NULL)
 BTF_ID_FLAGS(func, bpf_obj_drop_impl, KF_RELEASE)
 BTF_ID_FLAGS(func, bpf_percpu_obj_drop_impl, KF_RELEASE)
 BTF_ID_FLAGS(func, bpf_refcount_acquire_impl, KF_ACQUIRE | KF_RET_NULL | KF_RCU)
 BTF_ID_FLAGS(func, bpf_list_push_front_impl)
 BTF_ID_FLAGS(func, bpf_list_push_back_impl)
 BTF_ID_FLAGS(func, bpf_list_pop_front, KF_ACQUIRE | KF_RET_NULL)
 BTF_ID_FLAGS(func, bpf_list_pop_back, KF_ACQUIRE | KF_RET_NULL)
 BTF_ID_FLAGS(func, bpf_task_acquire, KF_ACQUIRE | KF_RCU | KF_RET_NULL)
 BTF_ID_FLAGS(func, bpf_task_release, KF_RELEASE)
 BTF_ID_FLAGS(func, bpf_rbtree_remove, KF_ACQUIRE | KF_RET_NULL)
 BTF_ID_FLAGS(func, bpf_rbtree_add_impl)
 BTF_ID_FLAGS(func, bpf_rbtree_first, KF_RET_NULL)
 
 #ifdef CONFIG_CGROUPS
 BTF_ID_FLAGS(func, bpf_cgroup_acquire, KF_ACQUIRE | KF_RCU | KF_RET_NULL)
 BTF_ID_FLAGS(func, bpf_cgroup_release, KF_RELEASE)
 BTF_ID_FLAGS(func, bpf_cgroup_ancestor, KF_ACQUIRE | KF_RCU | KF_RET_NULL)
 BTF_ID_FLAGS(func, bpf_cgroup_from_id, KF_ACQUIRE | KF_RET_NULL)
 BTF_ID_FLAGS(func, bpf_task_under_cgroup, KF_RCU)
 BTF_ID_FLAGS(func, bpf_task_get_cgroup1, KF_ACQUIRE | KF_RCU | KF_RET_NULL)
 #endif
 BTF_ID_FLAGS(func, bpf_task_from_pid, KF_ACQUIRE | KF_RET_NULL)
 BTF_ID_FLAGS(func, bpf_throw)
 BTF_KFUNCS_END(generic_btf_ids)
 
 static const struct btf_kfunc_id_set generic_kfunc_set = {
         .owner = THIS_MODULE,
         .set   = &generic_btf_ids,
 };
 
 
 BTF_ID_LIST(generic_dtor_ids)
 BTF_ID(struct, task_struct)
 BTF_ID(func, bpf_task_release_dtor)
 #ifdef CONFIG_CGROUPS
 BTF_ID(struct, cgroup)
 BTF_ID(func, bpf_cgroup_release_dtor)
 #endif
 
 BTF_KFUNCS_START(common_btf_ids)
 BTF_ID_FLAGS(func, bpf_cast_to_kern_ctx)
 BTF_ID_FLAGS(func, bpf_rdonly_cast)
 BTF_ID_FLAGS(func, bpf_rcu_read_lock)
 BTF_ID_FLAGS(func, bpf_rcu_read_unlock)
 BTF_ID_FLAGS(func, bpf_dynptr_slice, KF_RET_NULL)
 BTF_ID_FLAGS(func, bpf_dynptr_slice_rdwr, KF_RET_NULL)
 BTF_ID_FLAGS(func, bpf_iter_num_new, KF_ITER_NEW)
 BTF_ID_FLAGS(func, bpf_iter_num_next, KF_ITER_NEXT | KF_RET_NULL)
 BTF_ID_FLAGS(func, bpf_iter_num_destroy, KF_ITER_DESTROY)
 BTF_ID_FLAGS(func, bpf_iter_task_vma_new, KF_ITER_NEW | KF_RCU)
 BTF_ID_FLAGS(func, bpf_iter_task_vma_next, KF_ITER_NEXT | KF_RET_NULL)
 BTF_ID_FLAGS(func, bpf_iter_task_vma_destroy, KF_ITER_DESTROY)
 #ifdef CONFIG_CGROUPS
 BTF_ID_FLAGS(func, bpf_iter_css_task_new, KF_ITER_NEW | KF_TRUSTED_ARGS)
 BTF_ID_FLAGS(func, bpf_iter_css_task_next, KF_ITER_NEXT | KF_RET_NULL)
 BTF_ID_FLAGS(func, bpf_iter_css_task_destroy, KF_ITER_DESTROY)
 BTF_ID_FLAGS(func, bpf_iter_css_new, KF_ITER_NEW | KF_TRUSTED_ARGS | KF_RCU_PROTECTED)
 BTF_ID_FLAGS(func, bpf_iter_css_next, KF_ITER_NEXT | KF_RET_NULL)
 BTF_ID_FLAGS(func, bpf_iter_css_destroy, KF_ITER_DESTROY)
 #endif
 BTF_ID_FLAGS(func, bpf_iter_task_new, KF_ITER_NEW | KF_TRUSTED_ARGS | KF_RCU_PROTECTED)
 BTF_ID_FLAGS(func, bpf_iter_task_next, KF_ITER_NEXT | KF_RET_NULL)
 BTF_ID_FLAGS(func, bpf_iter_task_destroy, KF_ITER_DESTROY)
 BTF_ID_FLAGS(func, bpf_dynptr_adjust)
 BTF_ID_FLAGS(func, bpf_dynptr_is_null)
 BTF_ID_FLAGS(func, bpf_dynptr_is_rdonly)
 BTF_ID_FLAGS(func, bpf_dynptr_size)
 BTF_ID_FLAGS(func, bpf_dynptr_clone)
 BTF_ID_FLAGS(func, bpf_modify_return_test_tp)
 BTF_ID_FLAGS(func, bpf_wq_init)
 BTF_ID_FLAGS(func, bpf_wq_set_callback_impl)
 BTF_ID_FLAGS(func, bpf_wq_start)
 BTF_ID_FLAGS(func, bpf_preempt_disable)
 BTF_ID_FLAGS(func, bpf_preempt_enable)
 BTF_ID_FLAGS(func, bpf_iter_bits_new, KF_ITER_NEW)
 BTF_ID_FLAGS(func, bpf_iter_bits_next, KF_ITER_NEXT | KF_RET_NULL)
 BTF_ID_FLAGS(func, bpf_iter_bits_destroy, KF_ITER_DESTROY)
 BTF_KFUNCS_END(common_btf_ids)
 
 static const struct btf_kfunc_id_set common_kfunc_set = {
         .owner = THIS_MODULE,
         .set   = &common_btf_ids,
 };
 
 static int __init kfunc_init(void)
 {
         int ret;
         const struct btf_id_dtor_kfunc generic_dtors[] = {
                 {
                         .btf_id       = generic_dtor_ids[0],
                         .kfunc_btf_id = generic_dtor_ids[1]
                 },
 #ifdef CONFIG_CGROUPS
                 {
                         .btf_id       = generic_dtor_ids[2],
                         .kfunc_btf_id = generic_dtor_ids[3]
                 },
 #endif
         };
 
         ret = register_btf_kfunc_id_set(BPF_PROG_TYPE_TRACING, &generic_kfunc_set);
         ret = ret ?: register_btf_kfunc_id_set(BPF_PROG_TYPE_SCHED_CLS, &generic_kfunc_set);
         ret = ret ?: register_btf_kfunc_id_set(BPF_PROG_TYPE_XDP, &generic_kfunc_set);
         ret = ret ?: register_btf_kfunc_id_set(BPF_PROG_TYPE_STRUCT_OPS, &generic_kfunc_set);
         ret = ret ?: register_btf_kfunc_id_set(BPF_PROG_TYPE_SYSCALL, &generic_kfunc_set);
         ret = ret ?: register_btf_id_dtor_kfuncs(generic_dtors,
                                                   ARRAY_SIZE(generic_dtors),
                                                   THIS_MODULE);
         return ret ?: register_btf_kfunc_id_set(BPF_PROG_TYPE_UNSPEC, &common_kfunc_set);
 }
 
 late_initcall(kfunc_init);
 
 /* Get a pointer to dynptr data up to len bytes for read only access. If
  * the dynptr doesn't have continuous data up to len bytes, return NULL.
  */
 const void *__bpf_dynptr_data(const struct bpf_dynptr_kern *ptr, u32 len)
 {
         const struct bpf_dynptr *p = (struct bpf_dynptr *)ptr;
 
         return bpf_dynptr_slice(p, 0, NULL, len);
 }
 
 /* Get a pointer to dynptr data up to len bytes for read write access. If
  * the dynptr doesn't have continuous data up to len bytes, or the dynptr
  * is read only, return NULL.
  */
 void *__bpf_dynptr_data_rw(const struct bpf_dynptr_kern *ptr, u32 len)
 {
         if (__bpf_dynptr_is_rdonly(ptr))
                 return NULL;
         return (void *)__bpf_dynptr_data(ptr, len);
 }
 

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