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	Version: linux-6.0.1 spark-3.0.0 hadoop-3.2.0-src hadoop-3.3.0-src spark-2.4.7 linux-4.15.13 hadoop-2.7.4-src Revert   Change

 // SPDX-License-Identifier: GPL-2.0
 /* Copyright (c) 2011-2015 PLUMgrid, http://plumgrid.com
  * Copyright (c) 2016 Facebook
  */
 #include <linux/kernel.h>
 #include <linux/types.h>
 #include <linux/slab.h>
 #include <linux/bpf.h>
 #include <linux/bpf_perf_event.h>
 #include <linux/btf.h>
 #include <linux/filter.h>
 #include <linux/uaccess.h>
 #include <linux/ctype.h>
 #include <linux/kprobes.h>
 #include <linux/spinlock.h>
 #include <linux/syscalls.h>
 #include <linux/error-injection.h>
 #include <linux/btf_ids.h>
 #include <linux/bpf_lsm.h>
 #include <linux/fprobe.h>
 #include <linux/bsearch.h>
 #include <linux/sort.h>
 
 #include <net/bpf_sk_storage.h>
 
 #include <uapi/linux/bpf.h>
 #include <uapi/linux/btf.h>
 
 #include <asm/tlb.h>
 
 #include "trace_probe.h"
 #include "trace.h"
 
 #define CREATE_TRACE_POINTS
 #include "bpf_trace.h"
 
 #define bpf_event_rcu_dereference(p)                    \
     rcu_dereference_protected(p, lockdep_is_held(&bpf_event_mutex))
 
 #ifdef CONFIG_MODULES
 struct bpf_trace_module {
     struct module *module;
     struct list_head list;
 };
 
 static LIST_HEAD(bpf_trace_modules);
 static DEFINE_MUTEX(bpf_module_mutex);
 
 static struct bpf_raw_event_map *bpf_get_raw_tracepoint_module(const char *name)
 {
     struct bpf_raw_event_map *btp, *ret = NULL;
     struct bpf_trace_module *btm;
     unsigned int i;
 
     mutex_lock(&bpf_module_mutex);
     list_for_each_entry(btm, &bpf_trace_modules, list) {
         for (i = 0; i < btm->module->num_bpf_raw_events; ++i) {
             btp = &btm->module->bpf_raw_events[i];
             if (!strcmp(btp->tp->name, name)) {
                 if (try_module_get(btm->module))
                     ret = btp;
                 goto out;
             }
         }
     }
 out:
     mutex_unlock(&bpf_module_mutex);
     return ret;
 }
 #else
 static struct bpf_raw_event_map *bpf_get_raw_tracepoint_module(const char *name)
 {
     return NULL;
 }
 #endif /* CONFIG_MODULES */
 
 u64 bpf_get_stackid(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5);
 u64 bpf_get_stack(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5);
 
 static int bpf_btf_printf_prepare(struct btf_ptr *ptr, u32 btf_ptr_size,
                   u64 flags, const struct btf **btf,
                   s32 *btf_id);
 static u64 bpf_kprobe_multi_cookie(struct bpf_run_ctx *ctx);
 static u64 bpf_kprobe_multi_entry_ip(struct bpf_run_ctx *ctx);
 
 /**
  * trace_call_bpf - invoke BPF program
  * @call: tracepoint event
  * @ctx: opaque context pointer
  *
  * kprobe handlers execute BPF programs via this helper.
  * Can be used from static tracepoints in the future.
  *
  * Return: BPF programs always return an integer which is interpreted by
  * kprobe handler as:
  * 0 - return from kprobe (event is filtered out)
  * 1 - store kprobe event into ring buffer
  * Other values are reserved and currently alias to 1
  */
 unsigned int trace_call_bpf(struct trace_event_call *call, void *ctx)
 {
     unsigned int ret;
 
     cant_sleep();
 
     if (unlikely(__this_cpu_inc_return(bpf_prog_active) != 1)) {
         /*
          * since some bpf program is already running on this cpu,
          * don't call into another bpf program (same or different)
          * and don't send kprobe event into ring-buffer,
          * so return zero here
          */
         ret = 0;
         goto out;
     }
 
     /*
      * Instead of moving rcu_read_lock/rcu_dereference/rcu_read_unlock
      * to all call sites, we did a bpf_prog_array_valid() there to check
      * whether call->prog_array is empty or not, which is
      * a heuristic to speed up execution.
      *
      * If bpf_prog_array_valid() fetched prog_array was
      * non-NULL, we go into trace_call_bpf() and do the actual
      * proper rcu_dereference() under RCU lock.
      * If it turns out that prog_array is NULL then, we bail out.
      * For the opposite, if the bpf_prog_array_valid() fetched pointer
      * was NULL, you'll skip the prog_array with the risk of missing
      * out of events when it was updated in between this and the
      * rcu_dereference() which is accepted risk.
      */
     rcu_read_lock();
     ret = bpf_prog_run_array(rcu_dereference(call->prog_array),
                  ctx, bpf_prog_run);
     rcu_read_unlock();
 
  out:
     __this_cpu_dec(bpf_prog_active);
 
     return ret;
 }
 
 #ifdef CONFIG_BPF_KPROBE_OVERRIDE
 BPF_CALL_2(bpf_override_return, struct pt_regs *, regs, unsigned long, rc)
 {
     regs_set_return_value(regs, rc);
     override_function_with_return(regs);
     return 0;
 }
 
 static const struct bpf_func_proto bpf_override_return_proto = {
     .func       = bpf_override_return,
     .gpl_only   = true,
     .ret_type   = RET_INTEGER,
     .arg1_type  = ARG_PTR_TO_CTX,
     .arg2_type  = ARG_ANYTHING,
 };
 #endif
 
 static __always_inline int
 bpf_probe_read_user_common(void *dst, u32 size, const void __user *unsafe_ptr)
 {
     int ret;
 
     ret = copy_from_user_nofault(dst, unsafe_ptr, size);
     if (unlikely(ret < 0))
         memset(dst, 0, size);
     return ret;
 }
 
 BPF_CALL_3(bpf_probe_read_user, void *, dst, u32, size,
        const void __user *, unsafe_ptr)
 {
     return bpf_probe_read_user_common(dst, size, unsafe_ptr);
 }
 
 const struct bpf_func_proto bpf_probe_read_user_proto = {
     .func       = bpf_probe_read_user,
     .gpl_only   = true,
     .ret_type   = RET_INTEGER,
     .arg1_type  = ARG_PTR_TO_UNINIT_MEM,
     .arg2_type  = ARG_CONST_SIZE_OR_ZERO,
     .arg3_type  = ARG_ANYTHING,
 };
 
 static __always_inline int
 bpf_probe_read_user_str_common(void *dst, u32 size,
                    const void __user *unsafe_ptr)
 {
     int ret;
 
     /*
      * NB: We rely on strncpy_from_user() not copying junk past the NUL
      * terminator into `dst`.
      *
      * strncpy_from_user() does long-sized strides in the fast path. If the
      * strncpy does not mask out the bytes after the NUL in `unsafe_ptr`,
      * then there could be junk after the NUL in `dst`. If user takes `dst`
      * and keys a hash map with it, then semantically identical strings can
      * occupy multiple entries in the map.
      */
     ret = strncpy_from_user_nofault(dst, unsafe_ptr, size);
     if (unlikely(ret < 0))
         memset(dst, 0, size);
     return ret;
 }
 
 BPF_CALL_3(bpf_probe_read_user_str, void *, dst, u32, size,
        const void __user *, unsafe_ptr)
 {
     return bpf_probe_read_user_str_common(dst, size, unsafe_ptr);
 }
 
 const struct bpf_func_proto bpf_probe_read_user_str_proto = {
     .func       = bpf_probe_read_user_str,
     .gpl_only   = true,
     .ret_type   = RET_INTEGER,
     .arg1_type  = ARG_PTR_TO_UNINIT_MEM,
     .arg2_type  = ARG_CONST_SIZE_OR_ZERO,
     .arg3_type  = ARG_ANYTHING,
 };
 
 static __always_inline int
 bpf_probe_read_kernel_common(void *dst, u32 size, const void *unsafe_ptr)
 {
     int ret;
 
     ret = copy_from_kernel_nofault(dst, unsafe_ptr, size);
     if (unlikely(ret < 0))
         memset(dst, 0, size);
     return ret;
 }
 
 BPF_CALL_3(bpf_probe_read_kernel, void *, dst, u32, size,
        const void *, unsafe_ptr)
 {
     return bpf_probe_read_kernel_common(dst, size, unsafe_ptr);
 }
 
 const struct bpf_func_proto bpf_probe_read_kernel_proto = {
     .func       = bpf_probe_read_kernel,
     .gpl_only   = true,
     .ret_type   = RET_INTEGER,
     .arg1_type  = ARG_PTR_TO_UNINIT_MEM,
     .arg2_type  = ARG_CONST_SIZE_OR_ZERO,
     .arg3_type  = ARG_ANYTHING,
 };
 
 static __always_inline int
 bpf_probe_read_kernel_str_common(void *dst, u32 size, const void *unsafe_ptr)
 {
     int ret;
 
     /*
      * The strncpy_from_kernel_nofault() call will likely not fill the
      * entire buffer, but that's okay in this circumstance as we're probing
      * arbitrary memory anyway similar to bpf_probe_read_*() and might
      * as well probe the stack. Thus, memory is explicitly cleared
      * only in error case, so that improper users ignoring return
      * code altogether don't copy garbage; otherwise length of string
      * is returned that can be used for bpf_perf_event_output() et al.
      */
     ret = strncpy_from_kernel_nofault(dst, unsafe_ptr, size);
     if (unlikely(ret < 0))
         memset(dst, 0, size);
     return ret;
 }
 
 BPF_CALL_3(bpf_probe_read_kernel_str, void *, dst, u32, size,
        const void *, unsafe_ptr)
 {
     return bpf_probe_read_kernel_str_common(dst, size, unsafe_ptr);
 }
 
 const struct bpf_func_proto bpf_probe_read_kernel_str_proto = {
     .func       = bpf_probe_read_kernel_str,
     .gpl_only   = true,
     .ret_type   = RET_INTEGER,
     .arg1_type  = ARG_PTR_TO_UNINIT_MEM,
     .arg2_type  = ARG_CONST_SIZE_OR_ZERO,
     .arg3_type  = ARG_ANYTHING,
 };
 
 #ifdef CONFIG_ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE
 BPF_CALL_3(bpf_probe_read_compat, void *, dst, u32, size,
        const void *, unsafe_ptr)
 {
     if ((unsigned long)unsafe_ptr < TASK_SIZE) {
         return bpf_probe_read_user_common(dst, size,
                 (__force void __user *)unsafe_ptr);
     }
     return bpf_probe_read_kernel_common(dst, size, unsafe_ptr);
 }
 
 static const struct bpf_func_proto bpf_probe_read_compat_proto = {
     .func       = bpf_probe_read_compat,
     .gpl_only   = 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_3(bpf_probe_read_compat_str, void *, dst, u32, size,
        const void *, unsafe_ptr)
 {
     if ((unsigned long)unsafe_ptr < TASK_SIZE) {
         return bpf_probe_read_user_str_common(dst, size,
                 (__force void __user *)unsafe_ptr);
     }
     return bpf_probe_read_kernel_str_common(dst, size, unsafe_ptr);
 }
 
 static const struct bpf_func_proto bpf_probe_read_compat_str_proto = {
     .func       = bpf_probe_read_compat_str,
     .gpl_only   = true,
     .ret_type   = RET_INTEGER,
     .arg1_type  = ARG_PTR_TO_UNINIT_MEM,
     .arg2_type  = ARG_CONST_SIZE_OR_ZERO,
     .arg3_type  = ARG_ANYTHING,
 };
 #endif /* CONFIG_ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE */
 
 BPF_CALL_3(bpf_probe_write_user, void __user *, unsafe_ptr, const void *, src,
        u32, size)
 {
     /*
      * Ensure we're in user context which is safe for the helper to
      * run. This helper has no business in a kthread.
      *
      * access_ok() should prevent writing to non-user memory, but in
      * some situations (nommu, temporary switch, etc) access_ok() does
      * not provide enough validation, hence the check on KERNEL_DS.
      *
      * nmi_uaccess_okay() ensures the probe is not run in an interim
      * state, when the task or mm are switched. This is specifically
      * required to prevent the use of temporary mm.
      */
 
     if (unlikely(in_interrupt() ||
              current->flags & (PF_KTHREAD | PF_EXITING)))
         return -EPERM;
     if (unlikely(!nmi_uaccess_okay()))
         return -EPERM;
 
     return copy_to_user_nofault(unsafe_ptr, src, size);
 }
 
 static const struct bpf_func_proto bpf_probe_write_user_proto = {
     .func       = bpf_probe_write_user,
     .gpl_only   = true,
     .ret_type   = RET_INTEGER,
     .arg1_type  = ARG_ANYTHING,
     .arg2_type  = ARG_PTR_TO_MEM | MEM_RDONLY,
     .arg3_type  = ARG_CONST_SIZE,
 };
 
 static const struct bpf_func_proto *bpf_get_probe_write_proto(void)
 {
     if (!capable(CAP_SYS_ADMIN))
         return NULL;
 
     pr_warn_ratelimited("%s[%d] is installing a program with bpf_probe_write_user helper that may corrupt user memory!",
                 current->comm, task_pid_nr(current));
 
     return &bpf_probe_write_user_proto;
 }
 
 static DEFINE_RAW_SPINLOCK(trace_printk_lock);
 
 #define MAX_TRACE_PRINTK_VARARGS    3
 #define BPF_TRACE_PRINTK_SIZE       1024
 
 BPF_CALL_5(bpf_trace_printk, char *, fmt, u32, fmt_size, u64, arg1,
        u64, arg2, u64, arg3)
 {
     u64 args[MAX_TRACE_PRINTK_VARARGS] = { arg1, arg2, arg3 };
     u32 *bin_args;
     static char buf[BPF_TRACE_PRINTK_SIZE];
     unsigned long flags;
     int ret;
 
     ret = bpf_bprintf_prepare(fmt, fmt_size, args, &bin_args,
                   MAX_TRACE_PRINTK_VARARGS);
     if (ret < 0)
         return ret;
 
     raw_spin_lock_irqsave(&trace_printk_lock, flags);
     ret = bstr_printf(buf, sizeof(buf), fmt, bin_args);
 
     trace_bpf_trace_printk(buf);
     raw_spin_unlock_irqrestore(&trace_printk_lock, flags);
 
     bpf_bprintf_cleanup();
 
     return ret;
 }
 
 static const struct bpf_func_proto bpf_trace_printk_proto = {
     .func       = bpf_trace_printk,
     .gpl_only   = true,
     .ret_type   = RET_INTEGER,
     .arg1_type  = ARG_PTR_TO_MEM | MEM_RDONLY,
     .arg2_type  = ARG_CONST_SIZE,
 };
 
 static void __set_printk_clr_event(void)
 {
     /*
      * This program might be calling bpf_trace_printk,
      * so enable the associated bpf_trace/bpf_trace_printk event.
      * Repeat this each time as it is possible a user has
      * disabled bpf_trace_printk events.  By loading a program
      * calling bpf_trace_printk() however the user has expressed
      * the intent to see such events.
      */
     if (trace_set_clr_event("bpf_trace", "bpf_trace_printk", 1))
         pr_warn_ratelimited("could not enable bpf_trace_printk events");
 }
 
 const struct bpf_func_proto *bpf_get_trace_printk_proto(void)
 {
     __set_printk_clr_event();
     return &bpf_trace_printk_proto;
 }
 
 BPF_CALL_4(bpf_trace_vprintk, char *, fmt, u32, fmt_size, const void *, data,
        u32, data_len)
 {
     static char buf[BPF_TRACE_PRINTK_SIZE];
     unsigned long flags;
     int ret, num_args;
     u32 *bin_args;
 
     if (data_len & 7 || data_len > MAX_BPRINTF_VARARGS * 8 ||
         (data_len && !data))
         return -EINVAL;
     num_args = data_len / 8;
 
     ret = bpf_bprintf_prepare(fmt, fmt_size, data, &bin_args, num_args);
     if (ret < 0)
         return ret;
 
     raw_spin_lock_irqsave(&trace_printk_lock, flags);
     ret = bstr_printf(buf, sizeof(buf), fmt, bin_args);
 
     trace_bpf_trace_printk(buf);
     raw_spin_unlock_irqrestore(&trace_printk_lock, flags);
 
     bpf_bprintf_cleanup();
 
     return ret;
 }
 
 static const struct bpf_func_proto bpf_trace_vprintk_proto = {
     .func       = bpf_trace_vprintk,
     .gpl_only   = true,
     .ret_type   = RET_INTEGER,
     .arg1_type  = ARG_PTR_TO_MEM | MEM_RDONLY,
     .arg2_type  = ARG_CONST_SIZE,
     .arg3_type  = ARG_PTR_TO_MEM | PTR_MAYBE_NULL | MEM_RDONLY,
     .arg4_type  = ARG_CONST_SIZE_OR_ZERO,
 };
 
 const struct bpf_func_proto *bpf_get_trace_vprintk_proto(void)
 {
     __set_printk_clr_event();
     return &bpf_trace_vprintk_proto;
 }
 
 BPF_CALL_5(bpf_seq_printf, struct seq_file *, m, char *, fmt, u32, fmt_size,
        const void *, data, u32, data_len)
 {
     int err, num_args;
     u32 *bin_args;
 
     if (data_len & 7 || data_len > MAX_BPRINTF_VARARGS * 8 ||
         (data_len && !data))
         return -EINVAL;
     num_args = data_len / 8;
 
     err = bpf_bprintf_prepare(fmt, fmt_size, data, &bin_args, num_args);
     if (err < 0)
         return err;
 
     seq_bprintf(m, fmt, bin_args);
 
     bpf_bprintf_cleanup();
 
     return seq_has_overflowed(m) ? -EOVERFLOW : 0;
 }
 
 BTF_ID_LIST_SINGLE(btf_seq_file_ids, struct, seq_file)
 
 static const struct bpf_func_proto bpf_seq_printf_proto = {
     .func       = bpf_seq_printf,
     .gpl_only   = true,
     .ret_type   = RET_INTEGER,
     .arg1_type  = ARG_PTR_TO_BTF_ID,
     .arg1_btf_id    = &btf_seq_file_ids[0],
     .arg2_type  = ARG_PTR_TO_MEM | MEM_RDONLY,
     .arg3_type  = ARG_CONST_SIZE,
     .arg4_type      = ARG_PTR_TO_MEM | PTR_MAYBE_NULL | MEM_RDONLY,
     .arg5_type      = ARG_CONST_SIZE_OR_ZERO,
 };
 
 BPF_CALL_3(bpf_seq_write, struct seq_file *, m, const void *, data, u32, len)
 {
     return seq_write(m, data, len) ? -EOVERFLOW : 0;
 }
 
 static const struct bpf_func_proto bpf_seq_write_proto = {
     .func       = bpf_seq_write,
     .gpl_only   = true,
     .ret_type   = RET_INTEGER,
     .arg1_type  = ARG_PTR_TO_BTF_ID,
     .arg1_btf_id    = &btf_seq_file_ids[0],
     .arg2_type  = ARG_PTR_TO_MEM | MEM_RDONLY,
     .arg3_type  = ARG_CONST_SIZE_OR_ZERO,
 };
 
 BPF_CALL_4(bpf_seq_printf_btf, struct seq_file *, m, struct btf_ptr *, ptr,
        u32, btf_ptr_size, u64, flags)
 {
     const struct btf *btf;
     s32 btf_id;
     int ret;
 
     ret = bpf_btf_printf_prepare(ptr, btf_ptr_size, flags, &btf, &btf_id);
     if (ret)
         return ret;
 
     return btf_type_seq_show_flags(btf, btf_id, ptr->ptr, m, flags);
 }
 
 static const struct bpf_func_proto bpf_seq_printf_btf_proto = {
     .func       = bpf_seq_printf_btf,
     .gpl_only   = true,
     .ret_type   = RET_INTEGER,
     .arg1_type  = ARG_PTR_TO_BTF_ID,
     .arg1_btf_id    = &btf_seq_file_ids[0],
     .arg2_type  = ARG_PTR_TO_MEM | MEM_RDONLY,
     .arg3_type  = ARG_CONST_SIZE_OR_ZERO,
     .arg4_type  = ARG_ANYTHING,
 };
 
 static __always_inline int
 get_map_perf_counter(struct bpf_map *map, u64 flags,
              u64 *value, u64 *enabled, u64 *running)
 {
     struct bpf_array *array = container_of(map, struct bpf_array, map);
     unsigned int cpu = smp_processor_id();
     u64 index = flags & BPF_F_INDEX_MASK;
     struct bpf_event_entry *ee;
 
     if (unlikely(flags & ~(BPF_F_INDEX_MASK)))
         return -EINVAL;
     if (index == BPF_F_CURRENT_CPU)
         index = cpu;
     if (unlikely(index >= array->map.max_entries))
         return -E2BIG;
 
     ee = READ_ONCE(array->ptrs[index]);
     if (!ee)
         return -ENOENT;
 
     return perf_event_read_local(ee->event, value, enabled, running);
 }
 
 BPF_CALL_2(bpf_perf_event_read, struct bpf_map *, map, u64, flags)
 {
     u64 value = 0;
     int err;
 
     err = get_map_perf_counter(map, flags, &value, NULL, NULL);
     /*
      * this api is ugly since we miss [-22..-2] range of valid
      * counter values, but that's uapi
      */
     if (err)
         return err;
     return value;
 }
 
 static const struct bpf_func_proto bpf_perf_event_read_proto = {
     .func       = bpf_perf_event_read,
     .gpl_only   = true,
     .ret_type   = RET_INTEGER,
     .arg1_type  = ARG_CONST_MAP_PTR,
     .arg2_type  = ARG_ANYTHING,
 };
 
 BPF_CALL_4(bpf_perf_event_read_value, struct bpf_map *, map, u64, flags,
        struct bpf_perf_event_value *, buf, u32, size)
 {
     int err = -EINVAL;
 
     if (unlikely(size != sizeof(struct bpf_perf_event_value)))
         goto clear;
     err = get_map_perf_counter(map, flags, &buf->counter, &buf->enabled,
                    &buf->running);
     if (unlikely(err))
         goto clear;
     return 0;
 clear:
     memset(buf, 0, size);
     return err;
 }
 
 static const struct bpf_func_proto bpf_perf_event_read_value_proto = {
     .func       = bpf_perf_event_read_value,
     .gpl_only   = true,
     .ret_type   = RET_INTEGER,
     .arg1_type  = ARG_CONST_MAP_PTR,
     .arg2_type  = ARG_ANYTHING,
     .arg3_type  = ARG_PTR_TO_UNINIT_MEM,
     .arg4_type  = ARG_CONST_SIZE,
 };
 
 static __always_inline u64
 __bpf_perf_event_output(struct pt_regs *regs, struct bpf_map *map,
             u64 flags, struct perf_sample_data *sd)
 {
     struct bpf_array *array = container_of(map, struct bpf_array, map);
     unsigned int cpu = smp_processor_id();
     u64 index = flags & BPF_F_INDEX_MASK;
     struct bpf_event_entry *ee;
     struct perf_event *event;
 
     if (index == BPF_F_CURRENT_CPU)
         index = cpu;
     if (unlikely(index >= array->map.max_entries))
         return -E2BIG;
 
     ee = READ_ONCE(array->ptrs[index]);
     if (!ee)
         return -ENOENT;
 
     event = ee->event;
     if (unlikely(event->attr.type != PERF_TYPE_SOFTWARE ||
              event->attr.config != PERF_COUNT_SW_BPF_OUTPUT))
         return -EINVAL;
 
     if (unlikely(event->oncpu != cpu))
         return -EOPNOTSUPP;
 
     return perf_event_output(event, sd, regs);
 }
 
 /*
  * Support executing tracepoints in normal, irq, and nmi context that each call
  * bpf_perf_event_output
  */
 struct bpf_trace_sample_data {
     struct perf_sample_data sds[3];
 };
 
 static DEFINE_PER_CPU(struct bpf_trace_sample_data, bpf_trace_sds);
 static DEFINE_PER_CPU(int, bpf_trace_nest_level);
 BPF_CALL_5(bpf_perf_event_output, struct pt_regs *, regs, struct bpf_map *, map,
        u64, flags, void *, data, u64, size)
 {
     struct bpf_trace_sample_data *sds = this_cpu_ptr(&bpf_trace_sds);
     int nest_level = this_cpu_inc_return(bpf_trace_nest_level);
     struct perf_raw_record raw = {
         .frag = {
             .size = size,
             .data = data,
         },
     };
     struct perf_sample_data *sd;
     int err;
 
     if (WARN_ON_ONCE(nest_level > ARRAY_SIZE(sds->sds))) {
         err = -EBUSY;
         goto out;
     }
 
     sd = &sds->sds[nest_level - 1];
 
     if (unlikely(flags & ~(BPF_F_INDEX_MASK))) {
         err = -EINVAL;
         goto out;
     }
 
     perf_sample_data_init(sd, 0, 0);
     sd->raw = &raw;
 
     err = __bpf_perf_event_output(regs, map, flags, sd);
 
 out:
     this_cpu_dec(bpf_trace_nest_level);
     return err;
 }
 
 static const struct bpf_func_proto bpf_perf_event_output_proto = {
     .func       = bpf_perf_event_output,
     .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,
 };
 
 static DEFINE_PER_CPU(int, bpf_event_output_nest_level);
 struct bpf_nested_pt_regs {
     struct pt_regs regs[3];
 };
 static DEFINE_PER_CPU(struct bpf_nested_pt_regs, bpf_pt_regs);
 static DEFINE_PER_CPU(struct bpf_trace_sample_data, bpf_misc_sds);
 
 u64 bpf_event_output(struct bpf_map *map, u64 flags, void *meta, u64 meta_size,
              void *ctx, u64 ctx_size, bpf_ctx_copy_t ctx_copy)
 {
     int nest_level = this_cpu_inc_return(bpf_event_output_nest_level);
     struct perf_raw_frag frag = {
         .copy       = ctx_copy,
         .size       = ctx_size,
         .data       = ctx,
     };
     struct perf_raw_record raw = {
         .frag = {
             {
                 .next   = ctx_size ? &frag : NULL,
             },
             .size   = meta_size,
             .data   = meta,
         },
     };
     struct perf_sample_data *sd;
     struct pt_regs *regs;
     u64 ret;
 
     if (WARN_ON_ONCE(nest_level > ARRAY_SIZE(bpf_misc_sds.sds))) {
         ret = -EBUSY;
         goto out;
     }
     sd = this_cpu_ptr(&bpf_misc_sds.sds[nest_level - 1]);
     regs = this_cpu_ptr(&bpf_pt_regs.regs[nest_level - 1]);
 
     perf_fetch_caller_regs(regs);
     perf_sample_data_init(sd, 0, 0);
     sd->raw = &raw;
 
     ret = __bpf_perf_event_output(regs, map, flags, sd);
 out:
     this_cpu_dec(bpf_event_output_nest_level);
     return ret;
 }
 
 BPF_CALL_0(bpf_get_current_task)
 {
     return (long) current;
 }
 
 const struct bpf_func_proto bpf_get_current_task_proto = {
     .func       = bpf_get_current_task,
     .gpl_only   = true,
     .ret_type   = RET_INTEGER,
 };
 
 BPF_CALL_0(bpf_get_current_task_btf)
 {
     return (unsigned long) current;
 }
 
 const struct bpf_func_proto bpf_get_current_task_btf_proto = {
     .func       = bpf_get_current_task_btf,
     .gpl_only   = true,
     .ret_type   = RET_PTR_TO_BTF_ID,
     .ret_btf_id = &btf_tracing_ids[BTF_TRACING_TYPE_TASK],
 };
 
 BPF_CALL_1(bpf_task_pt_regs, struct task_struct *, task)
 {
     return (unsigned long) task_pt_regs(task);
 }
 
 BTF_ID_LIST(bpf_task_pt_regs_ids)
 BTF_ID(struct, pt_regs)
 
 const struct bpf_func_proto bpf_task_pt_regs_proto = {
     .func       = bpf_task_pt_regs,
     .gpl_only   = true,
     .arg1_type  = ARG_PTR_TO_BTF_ID,
     .arg1_btf_id    = &btf_tracing_ids[BTF_TRACING_TYPE_TASK],
     .ret_type   = RET_PTR_TO_BTF_ID,
     .ret_btf_id = &bpf_task_pt_regs_ids[0],
 };
 
 BPF_CALL_2(bpf_current_task_under_cgroup, struct bpf_map *, map, u32, idx)
 {
     struct bpf_array *array = container_of(map, struct bpf_array, map);
     struct cgroup *cgrp;
 
     if (unlikely(idx >= array->map.max_entries))
         return -E2BIG;
 
     cgrp = READ_ONCE(array->ptrs[idx]);
     if (unlikely(!cgrp))
         return -EAGAIN;
 
     return task_under_cgroup_hierarchy(current, cgrp);
 }
 
 static const struct bpf_func_proto bpf_current_task_under_cgroup_proto = {
     .func           = bpf_current_task_under_cgroup,
     .gpl_only       = false,
     .ret_type       = RET_INTEGER,
     .arg1_type      = ARG_CONST_MAP_PTR,
     .arg2_type      = ARG_ANYTHING,
 };
 
 struct send_signal_irq_work {
     struct irq_work irq_work;
     struct task_struct *task;
     u32 sig;
     enum pid_type type;
 };
 
 static DEFINE_PER_CPU(struct send_signal_irq_work, send_signal_work);
 
 static void do_bpf_send_signal(struct irq_work *entry)
 {
     struct send_signal_irq_work *work;
 
     work = container_of(entry, struct send_signal_irq_work, irq_work);
     group_send_sig_info(work->sig, SEND_SIG_PRIV, work->task, work->type);
 }
 
 static int bpf_send_signal_common(u32 sig, enum pid_type type)
 {
     struct send_signal_irq_work *work = NULL;
 
     /* Similar to bpf_probe_write_user, task needs to be
      * in a sound condition and kernel memory access be
      * permitted in order to send signal to the current
      * task.
      */
     if (unlikely(current->flags & (PF_KTHREAD | PF_EXITING)))
         return -EPERM;
     if (unlikely(!nmi_uaccess_okay()))
         return -EPERM;
 
     if (irqs_disabled()) {
         /* Do an early check on signal validity. Otherwise,
          * the error is lost in deferred irq_work.
          */
         if (unlikely(!valid_signal(sig)))
             return -EINVAL;
 
         work = this_cpu_ptr(&send_signal_work);
         if (irq_work_is_busy(&work->irq_work))
             return -EBUSY;
 
         /* Add the current task, which is the target of sending signal,
          * to the irq_work. The current task may change when queued
          * irq works get executed.
          */
         work->task = current;
         work->sig = sig;
         work->type = type;
         irq_work_queue(&work->irq_work);
         return 0;
     }
 
     return group_send_sig_info(sig, SEND_SIG_PRIV, current, type);
 }
 
 BPF_CALL_1(bpf_send_signal, u32, sig)
 {
     return bpf_send_signal_common(sig, PIDTYPE_TGID);
 }
 
 static const struct bpf_func_proto bpf_send_signal_proto = {
     .func       = bpf_send_signal,
     .gpl_only   = false,
     .ret_type   = RET_INTEGER,
     .arg1_type  = ARG_ANYTHING,
 };
 
 BPF_CALL_1(bpf_send_signal_thread, u32, sig)
 {
     return bpf_send_signal_common(sig, PIDTYPE_PID);
 }
 
 static const struct bpf_func_proto bpf_send_signal_thread_proto = {
     .func       = bpf_send_signal_thread,
     .gpl_only   = false,
     .ret_type   = RET_INTEGER,
     .arg1_type  = ARG_ANYTHING,
 };
 
 BPF_CALL_3(bpf_d_path, struct path *, path, char *, buf, u32, sz)
 {
     long len;
     char *p;
 
     if (!sz)
         return 0;
 
     p = d_path(path, buf, sz);
     if (IS_ERR(p)) {
         len = PTR_ERR(p);
     } else {
         len = buf + sz - p;
         memmove(buf, p, len);
     }
 
     return len;
 }
 
 BTF_SET_START(btf_allowlist_d_path)
 #ifdef CONFIG_SECURITY
 BTF_ID(func, security_file_permission)
 BTF_ID(func, security_inode_getattr)
 BTF_ID(func, security_file_open)
 #endif
 #ifdef CONFIG_SECURITY_PATH
 BTF_ID(func, security_path_truncate)
 #endif
 BTF_ID(func, vfs_truncate)
 BTF_ID(func, vfs_fallocate)
 BTF_ID(func, dentry_open)
 BTF_ID(func, vfs_getattr)
 BTF_ID(func, filp_close)
 BTF_SET_END(btf_allowlist_d_path)
 
 static bool bpf_d_path_allowed(const struct bpf_prog *prog)
 {
     if (prog->type == BPF_PROG_TYPE_TRACING &&
         prog->expected_attach_type == BPF_TRACE_ITER)
         return true;
 
     if (prog->type == BPF_PROG_TYPE_LSM)
         return bpf_lsm_is_sleepable_hook(prog->aux->attach_btf_id);
 
     return btf_id_set_contains(&btf_allowlist_d_path,
                    prog->aux->attach_btf_id);
 }
 
 BTF_ID_LIST_SINGLE(bpf_d_path_btf_ids, struct, path)
 
 static const struct bpf_func_proto bpf_d_path_proto = {
     .func       = bpf_d_path,
     .gpl_only   = false,
     .ret_type   = RET_INTEGER,
     .arg1_type  = ARG_PTR_TO_BTF_ID,
     .arg1_btf_id    = &bpf_d_path_btf_ids[0],
     .arg2_type  = ARG_PTR_TO_MEM,
     .arg3_type  = ARG_CONST_SIZE_OR_ZERO,
     .allowed    = bpf_d_path_allowed,
 };
 
 #define BTF_F_ALL   (BTF_F_COMPACT  | BTF_F_NONAME | \
              BTF_F_PTR_RAW | BTF_F_ZERO)
 
 static int bpf_btf_printf_prepare(struct btf_ptr *ptr, u32 btf_ptr_size,
                   u64 flags, const struct btf **btf,
                   s32 *btf_id)
 {
     const struct btf_type *t;
 
     if (unlikely(flags & ~(BTF_F_ALL)))
         return -EINVAL;
 
     if (btf_ptr_size != sizeof(struct btf_ptr))
         return -EINVAL;
 
     *btf = bpf_get_btf_vmlinux();
 
     if (IS_ERR_OR_NULL(*btf))
         return IS_ERR(*btf) ? PTR_ERR(*btf) : -EINVAL;
 
     if (ptr->type_id > 0)
         *btf_id = ptr->type_id;
     else
         return -EINVAL;
 
     if (*btf_id > 0)
         t = btf_type_by_id(*btf, *btf_id);
     if (*btf_id <= 0 || !t)
         return -ENOENT;
 
     return 0;
 }
 
 BPF_CALL_5(bpf_snprintf_btf, char *, str, u32, str_size, struct btf_ptr *, ptr,
        u32, btf_ptr_size, u64, flags)
 {
     const struct btf *btf;
     s32 btf_id;
     int ret;
 
     ret = bpf_btf_printf_prepare(ptr, btf_ptr_size, flags, &btf, &btf_id);
     if (ret)
         return ret;
 
     return btf_type_snprintf_show(btf, btf_id, ptr->ptr, str, str_size,
                       flags);
 }
 
 const struct bpf_func_proto bpf_snprintf_btf_proto = {
     .func       = bpf_snprintf_btf,
     .gpl_only   = false,
     .ret_type   = RET_INTEGER,
     .arg1_type  = ARG_PTR_TO_MEM,
     .arg2_type  = ARG_CONST_SIZE,
     .arg3_type  = ARG_PTR_TO_MEM | MEM_RDONLY,
     .arg4_type  = ARG_CONST_SIZE,
     .arg5_type  = ARG_ANYTHING,
 };
 
 BPF_CALL_1(bpf_get_func_ip_tracing, void *, ctx)
 {
     /* This helper call is inlined by verifier. */
     return ((u64 *)ctx)[-2];
 }
 
 static const struct bpf_func_proto bpf_get_func_ip_proto_tracing = {
     .func       = bpf_get_func_ip_tracing,
     .gpl_only   = true,
     .ret_type   = RET_INTEGER,
     .arg1_type  = ARG_PTR_TO_CTX,
 };
 
 BPF_CALL_1(bpf_get_func_ip_kprobe, struct pt_regs *, regs)
 {
     struct kprobe *kp = kprobe_running();
 
     return kp ? (uintptr_t)kp->addr : 0;
 }
 
 static const struct bpf_func_proto bpf_get_func_ip_proto_kprobe = {
     .func       = bpf_get_func_ip_kprobe,
     .gpl_only   = true,
     .ret_type   = RET_INTEGER,
     .arg1_type  = ARG_PTR_TO_CTX,
 };
 
 BPF_CALL_1(bpf_get_func_ip_kprobe_multi, struct pt_regs *, regs)
 {
     return bpf_kprobe_multi_entry_ip(current->bpf_ctx);
 }
 
 static const struct bpf_func_proto bpf_get_func_ip_proto_kprobe_multi = {
     .func       = bpf_get_func_ip_kprobe_multi,
     .gpl_only   = false,
     .ret_type   = RET_INTEGER,
     .arg1_type  = ARG_PTR_TO_CTX,
 };
 
 BPF_CALL_1(bpf_get_attach_cookie_kprobe_multi, struct pt_regs *, regs)
 {
     return bpf_kprobe_multi_cookie(current->bpf_ctx);
 }
 
 static const struct bpf_func_proto bpf_get_attach_cookie_proto_kmulti = {
     .func       = bpf_get_attach_cookie_kprobe_multi,
     .gpl_only   = false,
     .ret_type   = RET_INTEGER,
     .arg1_type  = ARG_PTR_TO_CTX,
 };
 
 BPF_CALL_1(bpf_get_attach_cookie_trace, void *, ctx)
 {
     struct bpf_trace_run_ctx *run_ctx;
 
     run_ctx = container_of(current->bpf_ctx, struct bpf_trace_run_ctx, run_ctx);
     return run_ctx->bpf_cookie;
 }
 
 static const struct bpf_func_proto bpf_get_attach_cookie_proto_trace = {
     .func       = bpf_get_attach_cookie_trace,
     .gpl_only   = false,
     .ret_type   = RET_INTEGER,
     .arg1_type  = ARG_PTR_TO_CTX,
 };
 
 BPF_CALL_1(bpf_get_attach_cookie_pe, struct bpf_perf_event_data_kern *, ctx)
 {
     return ctx->event->bpf_cookie;
 }
 
 static const struct bpf_func_proto bpf_get_attach_cookie_proto_pe = {
     .func       = bpf_get_attach_cookie_pe,
     .gpl_only   = false,
     .ret_type   = RET_INTEGER,
     .arg1_type  = ARG_PTR_TO_CTX,
 };
 
 BPF_CALL_1(bpf_get_attach_cookie_tracing, void *, ctx)
 {
     struct bpf_trace_run_ctx *run_ctx;
 
     run_ctx = container_of(current->bpf_ctx, struct bpf_trace_run_ctx, run_ctx);
     return run_ctx->bpf_cookie;
 }
 
 static const struct bpf_func_proto bpf_get_attach_cookie_proto_tracing = {
     .func       = bpf_get_attach_cookie_tracing,
     .gpl_only   = false,
     .ret_type   = RET_INTEGER,
     .arg1_type  = ARG_PTR_TO_CTX,
 };
 
 BPF_CALL_3(bpf_get_branch_snapshot, void *, buf, u32, size, u64, flags)
 {
 #ifndef CONFIG_X86
     return -ENOENT;
 #else
     static const u32 br_entry_size = sizeof(struct perf_branch_entry);
     u32 entry_cnt = size / br_entry_size;
 
     entry_cnt = static_call(perf_snapshot_branch_stack)(buf, entry_cnt);
 
     if (unlikely(flags))
         return -EINVAL;
 
     if (!entry_cnt)
         return -ENOENT;
 
     return entry_cnt * br_entry_size;
 #endif
 }
 
 static const struct bpf_func_proto bpf_get_branch_snapshot_proto = {
     .func       = bpf_get_branch_snapshot,
     .gpl_only   = true,
     .ret_type   = RET_INTEGER,
     .arg1_type  = ARG_PTR_TO_UNINIT_MEM,
     .arg2_type  = ARG_CONST_SIZE_OR_ZERO,
 };
 
 BPF_CALL_3(get_func_arg, void *, ctx, u32, n, u64 *, value)
 {
     /* This helper call is inlined by verifier. */
     u64 nr_args = ((u64 *)ctx)[-1];
 
     if ((u64) n >= nr_args)
         return -EINVAL;
     *value = ((u64 *)ctx)[n];
     return 0;
 }
 
 static const struct bpf_func_proto bpf_get_func_arg_proto = {
     .func       = get_func_arg,
     .ret_type   = RET_INTEGER,
     .arg1_type  = ARG_PTR_TO_CTX,
     .arg2_type  = ARG_ANYTHING,
     .arg3_type  = ARG_PTR_TO_LONG,
 };
 
 BPF_CALL_2(get_func_ret, void *, ctx, u64 *, value)
 {
     /* This helper call is inlined by verifier. */
     u64 nr_args = ((u64 *)ctx)[-1];
 
     *value = ((u64 *)ctx)[nr_args];
     return 0;
 }
 
 static const struct bpf_func_proto bpf_get_func_ret_proto = {
     .func       = get_func_ret,
     .ret_type   = RET_INTEGER,
     .arg1_type  = ARG_PTR_TO_CTX,
     .arg2_type  = ARG_PTR_TO_LONG,
 };
 
 BPF_CALL_1(get_func_arg_cnt, void *, ctx)
 {
     /* This helper call is inlined by verifier. */
     return ((u64 *)ctx)[-1];
 }
 
 static const struct bpf_func_proto bpf_get_func_arg_cnt_proto = {
     .func       = get_func_arg_cnt,
     .ret_type   = RET_INTEGER,
     .arg1_type  = ARG_PTR_TO_CTX,
 };
 
 static const struct bpf_func_proto *
 bpf_tracing_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_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_tail_call:
         return &bpf_tail_call_proto;
     case BPF_FUNC_get_current_pid_tgid:
         return &bpf_get_current_pid_tgid_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_task_pt_regs:
         return &bpf_task_pt_regs_proto;
     case BPF_FUNC_get_current_uid_gid:
         return &bpf_get_current_uid_gid_proto;
     case BPF_FUNC_get_current_comm:
         return &bpf_get_current_comm_proto;
     case BPF_FUNC_trace_printk:
         return bpf_get_trace_printk_proto();
     case BPF_FUNC_get_smp_processor_id:
         return &bpf_get_smp_processor_id_proto;
     case BPF_FUNC_get_numa_node_id:
         return &bpf_get_numa_node_id_proto;
     case BPF_FUNC_perf_event_read:
         return &bpf_perf_event_read_proto;
     case BPF_FUNC_current_task_under_cgroup:
         return &bpf_current_task_under_cgroup_proto;
     case BPF_FUNC_get_prandom_u32:
         return &bpf_get_prandom_u32_proto;
     case BPF_FUNC_probe_write_user:
         return security_locked_down(LOCKDOWN_BPF_WRITE_USER) < 0 ?
                NULL : bpf_get_probe_write_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;
 #ifdef CONFIG_ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE
     case BPF_FUNC_probe_read:
         return security_locked_down(LOCKDOWN_BPF_READ_KERNEL) < 0 ?
                NULL : &bpf_probe_read_compat_proto;
     case BPF_FUNC_probe_read_str:
         return security_locked_down(LOCKDOWN_BPF_READ_KERNEL) < 0 ?
                NULL : &bpf_probe_read_compat_str_proto;
 #endif
 #ifdef CONFIG_CGROUPS
     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
     case BPF_FUNC_send_signal:
         return &bpf_send_signal_proto;
     case BPF_FUNC_send_signal_thread:
         return &bpf_send_signal_thread_proto;
     case BPF_FUNC_perf_event_read_value:
         return &bpf_perf_event_read_value_proto;
     case BPF_FUNC_get_ns_current_pid_tgid:
         return &bpf_get_ns_current_pid_tgid_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_jiffies64:
         return &bpf_jiffies64_proto;
     case BPF_FUNC_get_task_stack:
         return &bpf_get_task_stack_proto;
     case BPF_FUNC_copy_from_user:
         return prog->aux->sleepable ? &bpf_copy_from_user_proto : NULL;
     case BPF_FUNC_copy_from_user_task:
         return prog->aux->sleepable ? &bpf_copy_from_user_task_proto : NULL;
     case BPF_FUNC_snprintf_btf:
         return &bpf_snprintf_btf_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_task_storage_get:
         return &bpf_task_storage_get_proto;
     case BPF_FUNC_task_storage_delete:
         return &bpf_task_storage_delete_proto;
     case BPF_FUNC_for_each_map_elem:
         return &bpf_for_each_map_elem_proto;
     case BPF_FUNC_snprintf:
         return &bpf_snprintf_proto;
     case BPF_FUNC_get_func_ip:
         return &bpf_get_func_ip_proto_tracing;
     case BPF_FUNC_get_branch_snapshot:
         return &bpf_get_branch_snapshot_proto;
     case BPF_FUNC_find_vma:
         return &bpf_find_vma_proto;
     case BPF_FUNC_trace_vprintk:
         return bpf_get_trace_vprintk_proto();
     default:
         return bpf_base_func_proto(func_id);
     }
 }
 
 static const struct bpf_func_proto *
 kprobe_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
 {
     switch (func_id) {
     case BPF_FUNC_perf_event_output:
         return &bpf_perf_event_output_proto;
     case BPF_FUNC_get_stackid:
         return &bpf_get_stackid_proto;
     case BPF_FUNC_get_stack:
         return &bpf_get_stack_proto;
 #ifdef CONFIG_BPF_KPROBE_OVERRIDE
     case BPF_FUNC_override_return:
         return &bpf_override_return_proto;
 #endif
     case BPF_FUNC_get_func_ip:
         return prog->expected_attach_type == BPF_TRACE_KPROBE_MULTI ?
             &bpf_get_func_ip_proto_kprobe_multi :
             &bpf_get_func_ip_proto_kprobe;
     case BPF_FUNC_get_attach_cookie:
         return prog->expected_attach_type == BPF_TRACE_KPROBE_MULTI ?
             &bpf_get_attach_cookie_proto_kmulti :
             &bpf_get_attach_cookie_proto_trace;
     default:
         return bpf_tracing_func_proto(func_id, prog);
     }
 }
 
 /* bpf+kprobe programs can access fields of 'struct pt_regs' */
 static bool kprobe_prog_is_valid_access(int off, int size, enum bpf_access_type type,
                     const struct bpf_prog *prog,
                     struct bpf_insn_access_aux *info)
 {
     if (off < 0 || off >= sizeof(struct pt_regs))
         return false;
     if (type != BPF_READ)
         return false;
     if (off % size != 0)
         return false;
     /*
      * Assertion for 32 bit to make sure last 8 byte access
      * (BPF_DW) to the last 4 byte member is disallowed.
      */
     if (off + size > sizeof(struct pt_regs))
         return false;
 
     return true;
 }
 
 const struct bpf_verifier_ops kprobe_verifier_ops = {
     .get_func_proto  = kprobe_prog_func_proto,
     .is_valid_access = kprobe_prog_is_valid_access,
 };
 
 const struct bpf_prog_ops kprobe_prog_ops = {
 };
 
 BPF_CALL_5(bpf_perf_event_output_tp, void *, tp_buff, struct bpf_map *, map,
        u64, flags, void *, data, u64, size)
 {
     struct pt_regs *regs = *(struct pt_regs **)tp_buff;
 
     /*
      * r1 points to perf tracepoint buffer where first 8 bytes are hidden
      * from bpf program and contain a pointer to 'struct pt_regs'. Fetch it
      * from there and call the same bpf_perf_event_output() helper inline.
      */
     return ____bpf_perf_event_output(regs, map, flags, data, size);
 }
 
 static const struct bpf_func_proto bpf_perf_event_output_proto_tp = {
     .func       = bpf_perf_event_output_tp,
     .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_get_stackid_tp, void *, tp_buff, struct bpf_map *, map,
        u64, flags)
 {
     struct pt_regs *regs = *(struct pt_regs **)tp_buff;
 
     /*
      * Same comment as in bpf_perf_event_output_tp(), only that this time
      * the other helper's function body cannot be inlined due to being
      * external, thus we need to call raw helper function.
      */
     return bpf_get_stackid((unsigned long) regs, (unsigned long) map,
                    flags, 0, 0);
 }
 
 static const struct bpf_func_proto bpf_get_stackid_proto_tp = {
     .func       = bpf_get_stackid_tp,
     .gpl_only   = true,
     .ret_type   = RET_INTEGER,
     .arg1_type  = ARG_PTR_TO_CTX,
     .arg2_type  = ARG_CONST_MAP_PTR,
     .arg3_type  = ARG_ANYTHING,
 };
 
 BPF_CALL_4(bpf_get_stack_tp, void *, tp_buff, void *, buf, u32, size,
        u64, flags)
 {
     struct pt_regs *regs = *(struct pt_regs **)tp_buff;
 
     return bpf_get_stack((unsigned long) regs, (unsigned long) buf,
                  (unsigned long) size, flags, 0);
 }
 
 static const struct bpf_func_proto bpf_get_stack_proto_tp = {
     .func       = bpf_get_stack_tp,
     .gpl_only   = true,
     .ret_type   = RET_INTEGER,
     .arg1_type  = ARG_PTR_TO_CTX,
     .arg2_type  = ARG_PTR_TO_UNINIT_MEM,
     .arg3_type  = ARG_CONST_SIZE_OR_ZERO,
     .arg4_type  = ARG_ANYTHING,
 };
 
 static const struct bpf_func_proto *
 tp_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
 {
     switch (func_id) {
     case BPF_FUNC_perf_event_output:
         return &bpf_perf_event_output_proto_tp;
     case BPF_FUNC_get_stackid:
         return &bpf_get_stackid_proto_tp;
     case BPF_FUNC_get_stack:
         return &bpf_get_stack_proto_tp;
     case BPF_FUNC_get_attach_cookie:
         return &bpf_get_attach_cookie_proto_trace;
     default:
         return bpf_tracing_func_proto(func_id, prog);
     }
 }
 
 static bool tp_prog_is_valid_access(int off, int size, enum bpf_access_type type,
                     const struct bpf_prog *prog,
                     struct bpf_insn_access_aux *info)
 {
     if (off < sizeof(void *) || off >= PERF_MAX_TRACE_SIZE)
         return false;
     if (type != BPF_READ)
         return false;
     if (off % size != 0)
         return false;
 
     BUILD_BUG_ON(PERF_MAX_TRACE_SIZE % sizeof(__u64));
     return true;
 }
 
 const struct bpf_verifier_ops tracepoint_verifier_ops = {
     .get_func_proto  = tp_prog_func_proto,
     .is_valid_access = tp_prog_is_valid_access,
 };
 
 const struct bpf_prog_ops tracepoint_prog_ops = {
 };
 
 BPF_CALL_3(bpf_perf_prog_read_value, struct bpf_perf_event_data_kern *, ctx,
        struct bpf_perf_event_value *, buf, u32, size)
 {
     int err = -EINVAL;
 
     if (unlikely(size != sizeof(struct bpf_perf_event_value)))
         goto clear;
     err = perf_event_read_local(ctx->event, &buf->counter, &buf->enabled,
                     &buf->running);
     if (unlikely(err))
         goto clear;
     return 0;
 clear:
     memset(buf, 0, size);
     return err;
 }
 
 static const struct bpf_func_proto bpf_perf_prog_read_value_proto = {
          .func           = bpf_perf_prog_read_value,
          .gpl_only       = true,
          .ret_type       = RET_INTEGER,
          .arg1_type      = ARG_PTR_TO_CTX,
          .arg2_type      = ARG_PTR_TO_UNINIT_MEM,
          .arg3_type      = ARG_CONST_SIZE,
 };
 
 BPF_CALL_4(bpf_read_branch_records, struct bpf_perf_event_data_kern *, ctx,
        void *, buf, u32, size, u64, flags)
 {
     static const u32 br_entry_size = sizeof(struct perf_branch_entry);
     struct perf_branch_stack *br_stack = ctx->data->br_stack;
     u32 to_copy;
 
     if (unlikely(flags & ~BPF_F_GET_BRANCH_RECORDS_SIZE))
         return -EINVAL;
 
     if (unlikely(!br_stack))
         return -ENOENT;
 
     if (flags & BPF_F_GET_BRANCH_RECORDS_SIZE)
         return br_stack->nr * br_entry_size;
 
     if (!buf || (size % br_entry_size != 0))
         return -EINVAL;
 
     to_copy = min_t(u32, br_stack->nr * br_entry_size, size);
     memcpy(buf, br_stack->entries, to_copy);
 
     return to_copy;
 }
 
 static const struct bpf_func_proto bpf_read_branch_records_proto = {
     .func           = bpf_read_branch_records,
     .gpl_only       = true,
     .ret_type       = RET_INTEGER,
     .arg1_type      = ARG_PTR_TO_CTX,
     .arg2_type      = ARG_PTR_TO_MEM_OR_NULL,
     .arg3_type      = ARG_CONST_SIZE_OR_ZERO,
     .arg4_type      = ARG_ANYTHING,
 };
 
 static const struct bpf_func_proto *
 pe_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
 {
     switch (func_id) {
     case BPF_FUNC_perf_event_output:
         return &bpf_perf_event_output_proto_tp;
     case BPF_FUNC_get_stackid:
         return &bpf_get_stackid_proto_pe;
     case BPF_FUNC_get_stack:
         return &bpf_get_stack_proto_pe;
     case BPF_FUNC_perf_prog_read_value:
         return &bpf_perf_prog_read_value_proto;
     case BPF_FUNC_read_branch_records:
         return &bpf_read_branch_records_proto;
     case BPF_FUNC_get_attach_cookie:
         return &bpf_get_attach_cookie_proto_pe;
     default:
         return bpf_tracing_func_proto(func_id, prog);
     }
 }
 
 /*
  * bpf_raw_tp_regs are separate from bpf_pt_regs used from skb/xdp
  * to avoid potential recursive reuse issue when/if tracepoints are added
  * inside bpf_*_event_output, bpf_get_stackid and/or bpf_get_stack.
  *
  * Since raw tracepoints run despite bpf_prog_active, support concurrent usage
  * in normal, irq, and nmi context.
  */
 struct bpf_raw_tp_regs {
     struct pt_regs regs[3];
 };
 static DEFINE_PER_CPU(struct bpf_raw_tp_regs, bpf_raw_tp_regs);
 static DEFINE_PER_CPU(int, bpf_raw_tp_nest_level);
 static struct pt_regs *get_bpf_raw_tp_regs(void)
 {
     struct bpf_raw_tp_regs *tp_regs = this_cpu_ptr(&bpf_raw_tp_regs);
     int nest_level = this_cpu_inc_return(bpf_raw_tp_nest_level);
 
     if (WARN_ON_ONCE(nest_level > ARRAY_SIZE(tp_regs->regs))) {
         this_cpu_dec(bpf_raw_tp_nest_level);
         return ERR_PTR(-EBUSY);
     }
 
     return &tp_regs->regs[nest_level - 1];
 }
 
 static void put_bpf_raw_tp_regs(void)
 {
     this_cpu_dec(bpf_raw_tp_nest_level);
 }
 
 BPF_CALL_5(bpf_perf_event_output_raw_tp, struct bpf_raw_tracepoint_args *, args,
        struct bpf_map *, map, u64, flags, void *, data, u64, size)
 {
     struct pt_regs *regs = get_bpf_raw_tp_regs();
     int ret;
 
     if (IS_ERR(regs))
         return PTR_ERR(regs);
 
     perf_fetch_caller_regs(regs);
     ret = ____bpf_perf_event_output(regs, map, flags, data, size);
 
     put_bpf_raw_tp_regs();
     return ret;
 }
 
 static const struct bpf_func_proto bpf_perf_event_output_proto_raw_tp = {
     .func       = bpf_perf_event_output_raw_tp,
     .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,
 };
 
 extern const struct bpf_func_proto bpf_skb_output_proto;
 extern const struct bpf_func_proto bpf_xdp_output_proto;
 extern const struct bpf_func_proto bpf_xdp_get_buff_len_trace_proto;
 
 BPF_CALL_3(bpf_get_stackid_raw_tp, struct bpf_raw_tracepoint_args *, args,
        struct bpf_map *, map, u64, flags)
 {
     struct pt_regs *regs = get_bpf_raw_tp_regs();
     int ret;
 
     if (IS_ERR(regs))
         return PTR_ERR(regs);
 
     perf_fetch_caller_regs(regs);
     /* similar to bpf_perf_event_output_tp, but pt_regs fetched differently */
     ret = bpf_get_stackid((unsigned long) regs, (unsigned long) map,
                   flags, 0, 0);
     put_bpf_raw_tp_regs();
     return ret;
 }
 
 static const struct bpf_func_proto bpf_get_stackid_proto_raw_tp = {
     .func       = bpf_get_stackid_raw_tp,
     .gpl_only   = true,
     .ret_type   = RET_INTEGER,
     .arg1_type  = ARG_PTR_TO_CTX,
     .arg2_type  = ARG_CONST_MAP_PTR,
     .arg3_type  = ARG_ANYTHING,
 };
 
 BPF_CALL_4(bpf_get_stack_raw_tp, struct bpf_raw_tracepoint_args *, args,
        void *, buf, u32, size, u64, flags)
 {
     struct pt_regs *regs = get_bpf_raw_tp_regs();
     int ret;
 
     if (IS_ERR(regs))
         return PTR_ERR(regs);
 
     perf_fetch_caller_regs(regs);
     ret = bpf_get_stack((unsigned long) regs, (unsigned long) buf,
                 (unsigned long) size, flags, 0);
     put_bpf_raw_tp_regs();
     return ret;
 }
 
 static const struct bpf_func_proto bpf_get_stack_proto_raw_tp = {
     .func       = bpf_get_stack_raw_tp,
     .gpl_only   = true,
     .ret_type   = RET_INTEGER,
     .arg1_type  = ARG_PTR_TO_CTX,
     .arg2_type  = ARG_PTR_TO_MEM | MEM_RDONLY,
     .arg3_type  = ARG_CONST_SIZE_OR_ZERO,
     .arg4_type  = ARG_ANYTHING,
 };
 
 static const struct bpf_func_proto *
 raw_tp_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
 {
     switch (func_id) {
     case BPF_FUNC_perf_event_output:
         return &bpf_perf_event_output_proto_raw_tp;
     case BPF_FUNC_get_stackid:
         return &bpf_get_stackid_proto_raw_tp;
     case BPF_FUNC_get_stack:
         return &bpf_get_stack_proto_raw_tp;
     default:
         return bpf_tracing_func_proto(func_id, prog);
     }
 }
 
 const struct bpf_func_proto *
 tracing_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
 {
     const struct bpf_func_proto *fn;
 
     switch (func_id) {
 #ifdef CONFIG_NET
     case BPF_FUNC_skb_output:
         return &bpf_skb_output_proto;
     case BPF_FUNC_xdp_output:
         return &bpf_xdp_output_proto;
     case BPF_FUNC_skc_to_tcp6_sock:
         return &bpf_skc_to_tcp6_sock_proto;
     case BPF_FUNC_skc_to_tcp_sock:
         return &bpf_skc_to_tcp_sock_proto;
     case BPF_FUNC_skc_to_tcp_timewait_sock:
         return &bpf_skc_to_tcp_timewait_sock_proto;
     case BPF_FUNC_skc_to_tcp_request_sock:
         return &bpf_skc_to_tcp_request_sock_proto;
     case BPF_FUNC_skc_to_udp6_sock:
         return &bpf_skc_to_udp6_sock_proto;
     case BPF_FUNC_skc_to_unix_sock:
         return &bpf_skc_to_unix_sock_proto;
     case BPF_FUNC_skc_to_mptcp_sock:
         return &bpf_skc_to_mptcp_sock_proto;
     case BPF_FUNC_sk_storage_get:
         return &bpf_sk_storage_get_tracing_proto;
     case BPF_FUNC_sk_storage_delete:
         return &bpf_sk_storage_delete_tracing_proto;
     case BPF_FUNC_sock_from_file:
         return &bpf_sock_from_file_proto;
     case BPF_FUNC_get_socket_cookie:
         return &bpf_get_socket_ptr_cookie_proto;
     case BPF_FUNC_xdp_get_buff_len:
         return &bpf_xdp_get_buff_len_trace_proto;
 #endif
     case BPF_FUNC_seq_printf:
         return prog->expected_attach_type == BPF_TRACE_ITER ?
                &bpf_seq_printf_proto :
                NULL;
     case BPF_FUNC_seq_write:
         return prog->expected_attach_type == BPF_TRACE_ITER ?
                &bpf_seq_write_proto :
                NULL;
     case BPF_FUNC_seq_printf_btf:
         return prog->expected_attach_type == BPF_TRACE_ITER ?
                &bpf_seq_printf_btf_proto :
                NULL;
     case BPF_FUNC_d_path:
         return &bpf_d_path_proto;
     case BPF_FUNC_get_func_arg:
         return bpf_prog_has_trampoline(prog) ? &bpf_get_func_arg_proto : NULL;
     case BPF_FUNC_get_func_ret:
         return bpf_prog_has_trampoline(prog) ? &bpf_get_func_ret_proto : NULL;
     case BPF_FUNC_get_func_arg_cnt:
         return bpf_prog_has_trampoline(prog) ? &bpf_get_func_arg_cnt_proto : NULL;
     case BPF_FUNC_get_attach_cookie:
         return bpf_prog_has_trampoline(prog) ? &bpf_get_attach_cookie_proto_tracing : NULL;
     default:
         fn = raw_tp_prog_func_proto(func_id, prog);
         if (!fn && prog->expected_attach_type == BPF_TRACE_ITER)
             fn = bpf_iter_get_func_proto(func_id, prog);
         return fn;
     }
 }
 
 static bool raw_tp_prog_is_valid_access(int off, int size,
                     enum bpf_access_type type,
                     const struct bpf_prog *prog,
                     struct bpf_insn_access_aux *info)
 {
     return bpf_tracing_ctx_access(off, size, type);
 }
 
 static bool tracing_prog_is_valid_access(int off, int size,
                      enum bpf_access_type type,
                      const struct bpf_prog *prog,
                      struct bpf_insn_access_aux *info)
 {
     return bpf_tracing_btf_ctx_access(off, size, type, prog, info);
 }
 
 int __weak bpf_prog_test_run_tracing(struct bpf_prog *prog,
                      const union bpf_attr *kattr,
                      union bpf_attr __user *uattr)
 {
     return -ENOTSUPP;
 }
 
 const struct bpf_verifier_ops raw_tracepoint_verifier_ops = {
     .get_func_proto  = raw_tp_prog_func_proto,
     .is_valid_access = raw_tp_prog_is_valid_access,
 };
 
 const struct bpf_prog_ops raw_tracepoint_prog_ops = {
 #ifdef CONFIG_NET
     .test_run = bpf_prog_test_run_raw_tp,
 #endif
 };
 
 const struct bpf_verifier_ops tracing_verifier_ops = {
     .get_func_proto  = tracing_prog_func_proto,
     .is_valid_access = tracing_prog_is_valid_access,
 };
 
 const struct bpf_prog_ops tracing_prog_ops = {
     .test_run = bpf_prog_test_run_tracing,
 };
 
 static bool raw_tp_writable_prog_is_valid_access(int off, int size,
                          enum bpf_access_type type,
                          const struct bpf_prog *prog,
                          struct bpf_insn_access_aux *info)
 {
     if (off == 0) {
         if (size != sizeof(u64) || type != BPF_READ)
             return false;
         info->reg_type = PTR_TO_TP_BUFFER;
     }
     return raw_tp_prog_is_valid_access(off, size, type, prog, info);
 }
 
 const struct bpf_verifier_ops raw_tracepoint_writable_verifier_ops = {
     .get_func_proto  = raw_tp_prog_func_proto,
     .is_valid_access = raw_tp_writable_prog_is_valid_access,
 };
 
 const struct bpf_prog_ops raw_tracepoint_writable_prog_ops = {
 };
 
 static bool pe_prog_is_valid_access(int off, int size, enum bpf_access_type type,
                     const struct bpf_prog *prog,
                     struct bpf_insn_access_aux *info)
 {
     const int size_u64 = sizeof(u64);
 
     if (off < 0 || off >= sizeof(struct bpf_perf_event_data))
         return false;
     if (type != BPF_READ)
         return false;
     if (off % size != 0) {
         if (sizeof(unsigned long) != 4)
             return false;
         if (size != 8)
             return false;
         if (off % size != 4)
             return false;
     }
 
     switch (off) {
     case bpf_ctx_range(struct bpf_perf_event_data, sample_period):
         bpf_ctx_record_field_size(info, size_u64);
         if (!bpf_ctx_narrow_access_ok(off, size, size_u64))
             return false;
         break;
     case bpf_ctx_range(struct bpf_perf_event_data, addr):
         bpf_ctx_record_field_size(info, size_u64);
         if (!bpf_ctx_narrow_access_ok(off, size, size_u64))
             return false;
         break;
     default:
         if (size != sizeof(long))
             return false;
     }
 
     return true;
 }
 
 static u32 pe_prog_convert_ctx_access(enum bpf_access_type type,
                       const struct bpf_insn *si,
                       struct bpf_insn *insn_buf,
                       struct bpf_prog *prog, u32 *target_size)
 {
     struct bpf_insn *insn = insn_buf;
 
     switch (si->off) {
     case offsetof(struct bpf_perf_event_data, sample_period):
         *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct bpf_perf_event_data_kern,
                                data), si->dst_reg, si->src_reg,
                       offsetof(struct bpf_perf_event_data_kern, data));
         *insn++ = BPF_LDX_MEM(BPF_DW, si->dst_reg, si->dst_reg,
                       bpf_target_off(struct perf_sample_data, period, 8,
                              target_size));
         break;
     case offsetof(struct bpf_perf_event_data, addr):
         *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct bpf_perf_event_data_kern,
                                data), si->dst_reg, si->src_reg,
                       offsetof(struct bpf_perf_event_data_kern, data));
         *insn++ = BPF_LDX_MEM(BPF_DW, si->dst_reg, si->dst_reg,
                       bpf_target_off(struct perf_sample_data, addr, 8,
                              target_size));
         break;
     default:
         *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct bpf_perf_event_data_kern,
                                regs), si->dst_reg, si->src_reg,
                       offsetof(struct bpf_perf_event_data_kern, regs));
         *insn++ = BPF_LDX_MEM(BPF_SIZEOF(long), si->dst_reg, si->dst_reg,
                       si->off);
         break;
     }
 
     return insn - insn_buf;
 }
 
 const struct bpf_verifier_ops perf_event_verifier_ops = {
     .get_func_proto     = pe_prog_func_proto,
     .is_valid_access    = pe_prog_is_valid_access,
     .convert_ctx_access = pe_prog_convert_ctx_access,
 };
 
 const struct bpf_prog_ops perf_event_prog_ops = {
 };
 
 static DEFINE_MUTEX(bpf_event_mutex);
 
 #define BPF_TRACE_MAX_PROGS 64
 
 int perf_event_attach_bpf_prog(struct perf_event *event,
                    struct bpf_prog *prog,
                    u64 bpf_cookie)
 {
     struct bpf_prog_array *old_array;
     struct bpf_prog_array *new_array;
     int ret = -EEXIST;
 
     /*
      * Kprobe override only works if they are on the function entry,
      * and only if they are on the opt-in list.
      */
     if (prog->kprobe_override &&
         (!trace_kprobe_on_func_entry(event->tp_event) ||
          !trace_kprobe_error_injectable(event->tp_event)))
         return -EINVAL;
 
     mutex_lock(&bpf_event_mutex);
 
     if (event->prog)
         goto unlock;
 
     old_array = bpf_event_rcu_dereference(event->tp_event->prog_array);
     if (old_array &&
         bpf_prog_array_length(old_array) >= BPF_TRACE_MAX_PROGS) {
         ret = -E2BIG;
         goto unlock;
     }
 
     ret = bpf_prog_array_copy(old_array, NULL, prog, bpf_cookie, &new_array);
     if (ret < 0)
         goto unlock;
 
     /* set the new array to event->tp_event and set event->prog */
     event->prog = prog;
     event->bpf_cookie = bpf_cookie;
     rcu_assign_pointer(event->tp_event->prog_array, new_array);
     bpf_prog_array_free_sleepable(old_array);
 
 unlock:
     mutex_unlock(&bpf_event_mutex);
     return ret;
 }
 
 void perf_event_detach_bpf_prog(struct perf_event *event)
 {
     struct bpf_prog_array *old_array;
     struct bpf_prog_array *new_array;
     int ret;
 
     mutex_lock(&bpf_event_mutex);
 
     if (!event->prog)
         goto unlock;
 
     old_array = bpf_event_rcu_dereference(event->tp_event->prog_array);
     ret = bpf_prog_array_copy(old_array, event->prog, NULL, 0, &new_array);
     if (ret == -ENOENT)
         goto unlock;
     if (ret < 0) {
         bpf_prog_array_delete_safe(old_array, event->prog);
     } else {
         rcu_assign_pointer(event->tp_event->prog_array, new_array);
         bpf_prog_array_free_sleepable(old_array);
     }
 
     bpf_prog_put(event->prog);
     event->prog = NULL;
 
 unlock:
     mutex_unlock(&bpf_event_mutex);
 }
 
 int perf_event_query_prog_array(struct perf_event *event, void __user *info)
 {
     struct perf_event_query_bpf __user *uquery = info;
     struct perf_event_query_bpf query = {};
     struct bpf_prog_array *progs;
     u32 *ids, prog_cnt, ids_len;
     int ret;
 
     if (!perfmon_capable())
         return -EPERM;
     if (event->attr.type != PERF_TYPE_TRACEPOINT)
         return -EINVAL;
     if (copy_from_user(&query, uquery, sizeof(query)))
         return -EFAULT;
 
     ids_len = query.ids_len;
     if (ids_len > BPF_TRACE_MAX_PROGS)
         return -E2BIG;
     ids = kcalloc(ids_len, sizeof(u32), GFP_USER | __GFP_NOWARN);
     if (!ids)
         return -ENOMEM;
     /*
      * The above kcalloc returns ZERO_SIZE_PTR when ids_len = 0, which
      * is required when user only wants to check for uquery->prog_cnt.
      * There is no need to check for it since the case is handled
      * gracefully in bpf_prog_array_copy_info.
      */
 
     mutex_lock(&bpf_event_mutex);
     progs = bpf_event_rcu_dereference(event->tp_event->prog_array);
     ret = bpf_prog_array_copy_info(progs, ids, ids_len, &prog_cnt);
     mutex_unlock(&bpf_event_mutex);
 
     if (copy_to_user(&uquery->prog_cnt, &prog_cnt, sizeof(prog_cnt)) ||
         copy_to_user(uquery->ids, ids, ids_len * sizeof(u32)))
         ret = -EFAULT;
 
     kfree(ids);
     return ret;
 }
 
 extern struct bpf_raw_event_map __start__bpf_raw_tp[];
 extern struct bpf_raw_event_map __stop__bpf_raw_tp[];
 
 struct bpf_raw_event_map *bpf_get_raw_tracepoint(const char *name)
 {
     struct bpf_raw_event_map *btp = __start__bpf_raw_tp;
 
     for (; btp < __stop__bpf_raw_tp; btp++) {
         if (!strcmp(btp->tp->name, name))
             return btp;
     }
 
     return bpf_get_raw_tracepoint_module(name);
 }
 
 void bpf_put_raw_tracepoint(struct bpf_raw_event_map *btp)
 {
     struct module *mod;
 
     preempt_disable();
     mod = __module_address((unsigned long)btp);
     module_put(mod);
     preempt_enable();
 }
 
 static __always_inline
 void __bpf_trace_run(struct bpf_prog *prog, u64 *args)
 {
     cant_sleep();
     rcu_read_lock();
     (void) bpf_prog_run(prog, args);
     rcu_read_unlock();
 }
 
 #define UNPACK(...)         __VA_ARGS__
 #define REPEAT_1(FN, DL, X, ...)    FN(X)
 #define REPEAT_2(FN, DL, X, ...)    FN(X) UNPACK DL REPEAT_1(FN, DL, __VA_ARGS__)
 #define REPEAT_3(FN, DL, X, ...)    FN(X) UNPACK DL REPEAT_2(FN, DL, __VA_ARGS__)
 #define REPEAT_4(FN, DL, X, ...)    FN(X) UNPACK DL REPEAT_3(FN, DL, __VA_ARGS__)
 #define REPEAT_5(FN, DL, X, ...)    FN(X) UNPACK DL REPEAT_4(FN, DL, __VA_ARGS__)
 #define REPEAT_6(FN, DL, X, ...)    FN(X) UNPACK DL REPEAT_5(FN, DL, __VA_ARGS__)
 #define REPEAT_7(FN, DL, X, ...)    FN(X) UNPACK DL REPEAT_6(FN, DL, __VA_ARGS__)
 #define REPEAT_8(FN, DL, X, ...)    FN(X) UNPACK DL REPEAT_7(FN, DL, __VA_ARGS__)
 #define REPEAT_9(FN, DL, X, ...)    FN(X) UNPACK DL REPEAT_8(FN, DL, __VA_ARGS__)
 #define REPEAT_10(FN, DL, X, ...)   FN(X) UNPACK DL REPEAT_9(FN, DL, __VA_ARGS__)
 #define REPEAT_11(FN, DL, X, ...)   FN(X) UNPACK DL REPEAT_10(FN, DL, __VA_ARGS__)
 #define REPEAT_12(FN, DL, X, ...)   FN(X) UNPACK DL REPEAT_11(FN, DL, __VA_ARGS__)
 #define REPEAT(X, FN, DL, ...)      REPEAT_##X(FN, DL, __VA_ARGS__)
 
 #define SARG(X)     u64 arg##X
 #define COPY(X)     args[X] = arg##X
 
 #define __DL_COM    (,)
 #define __DL_SEM    (;)
 
 #define __SEQ_0_11  0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11
 
 #define BPF_TRACE_DEFN_x(x)                     \
     void bpf_trace_run##x(struct bpf_prog *prog,            \
                   REPEAT(x, SARG, __DL_COM, __SEQ_0_11))    \
     {                               \
         u64 args[x];                        \
         REPEAT(x, COPY, __DL_SEM, __SEQ_0_11);          \
         __bpf_trace_run(prog, args);                \
     }                               \
     EXPORT_SYMBOL_GPL(bpf_trace_run##x)
 BPF_TRACE_DEFN_x(1);
 BPF_TRACE_DEFN_x(2);
 BPF_TRACE_DEFN_x(3);
 BPF_TRACE_DEFN_x(4);
 BPF_TRACE_DEFN_x(5);
 BPF_TRACE_DEFN_x(6);
 BPF_TRACE_DEFN_x(7);
 BPF_TRACE_DEFN_x(8);
 BPF_TRACE_DEFN_x(9);
 BPF_TRACE_DEFN_x(10);
 BPF_TRACE_DEFN_x(11);
 BPF_TRACE_DEFN_x(12);
 
 static int __bpf_probe_register(struct bpf_raw_event_map *btp, struct bpf_prog *prog)
 {
     struct tracepoint *tp = btp->tp;
 
     /*
      * check that program doesn't access arguments beyond what's
      * available in this tracepoint
      */
     if (prog->aux->max_ctx_offset > btp->num_args * sizeof(u64))
         return -EINVAL;
 
     if (prog->aux->max_tp_access > btp->writable_size)
         return -EINVAL;
 
     return tracepoint_probe_register_may_exist(tp, (void *)btp->bpf_func,
                            prog);
 }
 
 int bpf_probe_register(struct bpf_raw_event_map *btp, struct bpf_prog *prog)
 {
     return __bpf_probe_register(btp, prog);
 }
 
 int bpf_probe_unregister(struct bpf_raw_event_map *btp, struct bpf_prog *prog)
 {
     return tracepoint_probe_unregister(btp->tp, (void *)btp->bpf_func, prog);
 }
 
 int bpf_get_perf_event_info(const struct perf_event *event, u32 *prog_id,
                 u32 *fd_type, const char **buf,
                 u64 *probe_offset, u64 *probe_addr)
 {
     bool is_tracepoint, is_syscall_tp;
     struct bpf_prog *prog;
     int flags, err = 0;
 
     prog = event->prog;
     if (!prog)
         return -ENOENT;
 
     /* not supporting BPF_PROG_TYPE_PERF_EVENT yet */
     if (prog->type == BPF_PROG_TYPE_PERF_EVENT)
         return -EOPNOTSUPP;
 
     *prog_id = prog->aux->id;
     flags = event->tp_event->flags;
     is_tracepoint = flags & TRACE_EVENT_FL_TRACEPOINT;
     is_syscall_tp = is_syscall_trace_event(event->tp_event);
 
     if (is_tracepoint || is_syscall_tp) {
         *buf = is_tracepoint ? event->tp_event->tp->name
                      : event->tp_event->name;
         *fd_type = BPF_FD_TYPE_TRACEPOINT;
         *probe_offset = 0x0;
         *probe_addr = 0x0;
     } else {
         /* kprobe/uprobe */
         err = -EOPNOTSUPP;
 #ifdef CONFIG_KPROBE_EVENTS
         if (flags & TRACE_EVENT_FL_KPROBE)
             err = bpf_get_kprobe_info(event, fd_type, buf,
                           probe_offset, probe_addr,
                           event->attr.type == PERF_TYPE_TRACEPOINT);
 #endif
 #ifdef CONFIG_UPROBE_EVENTS
         if (flags & TRACE_EVENT_FL_UPROBE)
             err = bpf_get_uprobe_info(event, fd_type, buf,
                           probe_offset,
                           event->attr.type == PERF_TYPE_TRACEPOINT);
 #endif
     }
 
     return err;
 }
 
 static int __init send_signal_irq_work_init(void)
 {
     int cpu;
     struct send_signal_irq_work *work;
 
     for_each_possible_cpu(cpu) {
         work = per_cpu_ptr(&send_signal_work, cpu);
         init_irq_work(&work->irq_work, do_bpf_send_signal);
     }
     return 0;
 }
 
 subsys_initcall(send_signal_irq_work_init);
 
 #ifdef CONFIG_MODULES
 static int bpf_event_notify(struct notifier_block *nb, unsigned long op,
                 void *module)
 {
     struct bpf_trace_module *btm, *tmp;
     struct module *mod = module;
     int ret = 0;
 
     if (mod->num_bpf_raw_events == 0 ||
         (op != MODULE_STATE_COMING && op != MODULE_STATE_GOING))
         goto out;
 
     mutex_lock(&bpf_module_mutex);
 
     switch (op) {
     case MODULE_STATE_COMING:
         btm = kzalloc(sizeof(*btm), GFP_KERNEL);
         if (btm) {
             btm->module = module;
             list_add(&btm->list, &bpf_trace_modules);
         } else {
             ret = -ENOMEM;
         }
         break;
     case MODULE_STATE_GOING:
         list_for_each_entry_safe(btm, tmp, &bpf_trace_modules, list) {
             if (btm->module == module) {
                 list_del(&btm->list);
                 kfree(btm);
                 break;
             }
         }
         break;
     }
 
     mutex_unlock(&bpf_module_mutex);
 
 out:
     return notifier_from_errno(ret);
 }
 
 static struct notifier_block bpf_module_nb = {
     .notifier_call = bpf_event_notify,
 };
 
 static int __init bpf_event_init(void)
 {
     register_module_notifier(&bpf_module_nb);
     return 0;
 }
 
 fs_initcall(bpf_event_init);
 #endif /* CONFIG_MODULES */
 
 #ifdef CONFIG_FPROBE
 struct bpf_kprobe_multi_link {
     struct bpf_link link;
     struct fprobe fp;
     unsigned long *addrs;
     u64 *cookies;
     u32 cnt;
 };
 
 struct bpf_kprobe_multi_run_ctx {
     struct bpf_run_ctx run_ctx;
     struct bpf_kprobe_multi_link *link;
     unsigned long entry_ip;
 };
 
 struct user_syms {
     const char **syms;
     char *buf;
 };
 
 static int copy_user_syms(struct user_syms *us, unsigned long __user *usyms, u32 cnt)
 {
     unsigned long __user usymbol;
     const char **syms = NULL;
     char *buf = NULL, *p;
     int err = -ENOMEM;
     unsigned int i;
 
     syms = kvmalloc_array(cnt, sizeof(*syms), GFP_KERNEL);
     if (!syms)
         goto error;
 
     buf = kvmalloc_array(cnt, KSYM_NAME_LEN, GFP_KERNEL);
     if (!buf)
         goto error;
 
     for (p = buf, i = 0; i < cnt; i++) {
         if (__get_user(usymbol, usyms + i)) {
             err = -EFAULT;
             goto error;
         }
         err = strncpy_from_user(p, (const char __user *) usymbol, KSYM_NAME_LEN);
         if (err == KSYM_NAME_LEN)
             err = -E2BIG;
         if (err < 0)
             goto error;
         syms[i] = p;
         p += err + 1;
     }
 
     us->syms = syms;
     us->buf = buf;
     return 0;
 
 error:
     if (err) {
         kvfree(syms);
         kvfree(buf);
     }
     return err;
 }
 
 static void free_user_syms(struct user_syms *us)
 {
     kvfree(us->syms);
     kvfree(us->buf);
 }
 
 static void bpf_kprobe_multi_link_release(struct bpf_link *link)
 {
     struct bpf_kprobe_multi_link *kmulti_link;
 
     kmulti_link = container_of(link, struct bpf_kprobe_multi_link, link);
     unregister_fprobe(&kmulti_link->fp);
 }
 
 static void bpf_kprobe_multi_link_dealloc(struct bpf_link *link)
 {
     struct bpf_kprobe_multi_link *kmulti_link;
 
     kmulti_link = container_of(link, struct bpf_kprobe_multi_link, link);
     kvfree(kmulti_link->addrs);
     kvfree(kmulti_link->cookies);
     kfree(kmulti_link);
 }
 
 static const struct bpf_link_ops bpf_kprobe_multi_link_lops = {
     .release = bpf_kprobe_multi_link_release,
     .dealloc = bpf_kprobe_multi_link_dealloc,
 };
 
 static void bpf_kprobe_multi_cookie_swap(void *a, void *b, int size, const void *priv)
 {
     const struct bpf_kprobe_multi_link *link = priv;
     unsigned long *addr_a = a, *addr_b = b;
     u64 *cookie_a, *cookie_b;
 
     cookie_a = link->cookies + (addr_a - link->addrs);
     cookie_b = link->cookies + (addr_b - link->addrs);
 
     /* swap addr_a/addr_b and cookie_a/cookie_b values */
     swap(*addr_a, *addr_b);
     swap(*cookie_a, *cookie_b);
 }
 
 static int __bpf_kprobe_multi_cookie_cmp(const void *a, const void *b)
 {
     const unsigned long *addr_a = a, *addr_b = b;
 
     if (*addr_a == *addr_b)
         return 0;
     return *addr_a < *addr_b ? -1 : 1;
 }
 
 static int bpf_kprobe_multi_cookie_cmp(const void *a, const void *b, const void *priv)
 {
     return __bpf_kprobe_multi_cookie_cmp(a, b);
 }
 
 static u64 bpf_kprobe_multi_cookie(struct bpf_run_ctx *ctx)
 {
     struct bpf_kprobe_multi_run_ctx *run_ctx;
     struct bpf_kprobe_multi_link *link;
     u64 *cookie, entry_ip;
     unsigned long *addr;
 
     if (WARN_ON_ONCE(!ctx))
         return 0;
     run_ctx = container_of(current->bpf_ctx, struct bpf_kprobe_multi_run_ctx, run_ctx);
     link = run_ctx->link;
     if (!link->cookies)
         return 0;
     entry_ip = run_ctx->entry_ip;
     addr = bsearch(&entry_ip, link->addrs, link->cnt, sizeof(entry_ip),
                __bpf_kprobe_multi_cookie_cmp);
     if (!addr)
         return 0;
     cookie = link->cookies + (addr - link->addrs);
     return *cookie;
 }
 
 static u64 bpf_kprobe_multi_entry_ip(struct bpf_run_ctx *ctx)
 {
     struct bpf_kprobe_multi_run_ctx *run_ctx;
 
     run_ctx = container_of(current->bpf_ctx, struct bpf_kprobe_multi_run_ctx, run_ctx);
     return run_ctx->entry_ip;
 }
 
 static int
 kprobe_multi_link_prog_run(struct bpf_kprobe_multi_link *link,
                unsigned long entry_ip, struct pt_regs *regs)
 {
     struct bpf_kprobe_multi_run_ctx run_ctx = {
         .link = link,
         .entry_ip = entry_ip,
     };
     struct bpf_run_ctx *old_run_ctx;
     int err;
 
     if (unlikely(__this_cpu_inc_return(bpf_prog_active) != 1)) {
         err = 0;
         goto out;
     }
 
     migrate_disable();
     rcu_read_lock();
     old_run_ctx = bpf_set_run_ctx(&run_ctx.run_ctx);
     err = bpf_prog_run(link->link.prog, regs);
     bpf_reset_run_ctx(old_run_ctx);
     rcu_read_unlock();
     migrate_enable();
 
  out:
     __this_cpu_dec(bpf_prog_active);
     return err;
 }
 
 static void
 kprobe_multi_link_handler(struct fprobe *fp, unsigned long entry_ip,
               struct pt_regs *regs)
 {
     struct bpf_kprobe_multi_link *link;
 
     link = container_of(fp, struct bpf_kprobe_multi_link, fp);
     kprobe_multi_link_prog_run(link, entry_ip, regs);
 }
 
 static int symbols_cmp_r(const void *a, const void *b, const void *priv)
 {
     const char **str_a = (const char **) a;
     const char **str_b = (const char **) b;
 
     return strcmp(*str_a, *str_b);
 }
 
 struct multi_symbols_sort {
     const char **funcs;
     u64 *cookies;
 };
 
 static void symbols_swap_r(void *a, void *b, int size, const void *priv)
 {
     const struct multi_symbols_sort *data = priv;
     const char **name_a = a, **name_b = b;
 
     swap(*name_a, *name_b);
 
     /* If defined, swap also related cookies. */
     if (data->cookies) {
         u64 *cookie_a, *cookie_b;
 
         cookie_a = data->cookies + (name_a - data->funcs);
         cookie_b = data->cookies + (name_b - data->funcs);
         swap(*cookie_a, *cookie_b);
     }
 }
 
 int bpf_kprobe_multi_link_attach(const union bpf_attr *attr, struct bpf_prog *prog)
 {
     struct bpf_kprobe_multi_link *link = NULL;
     struct bpf_link_primer link_primer;
     void __user *ucookies;
     unsigned long *addrs;
     u32 flags, cnt, size;
     void __user *uaddrs;
     u64 *cookies = NULL;
     void __user *usyms;
     int err;
 
     /* no support for 32bit archs yet */
     if (sizeof(u64) != sizeof(void *))
         return -EOPNOTSUPP;
 
     if (prog->expected_attach_type != BPF_TRACE_KPROBE_MULTI)
         return -EINVAL;
 
     flags = attr->link_create.kprobe_multi.flags;
     if (flags & ~BPF_F_KPROBE_MULTI_RETURN)
         return -EINVAL;
 
     uaddrs = u64_to_user_ptr(attr->link_create.kprobe_multi.addrs);
     usyms = u64_to_user_ptr(attr->link_create.kprobe_multi.syms);
     if (!!uaddrs == !!usyms)
         return -EINVAL;
 
     cnt = attr->link_create.kprobe_multi.cnt;
     if (!cnt)
         return -EINVAL;
 
     size = cnt * sizeof(*addrs);
     addrs = kvmalloc_array(cnt, sizeof(*addrs), GFP_KERNEL);
     if (!addrs)
         return -ENOMEM;
 
     ucookies = u64_to_user_ptr(attr->link_create.kprobe_multi.cookies);
     if (ucookies) {
         cookies = kvmalloc_array(cnt, sizeof(*addrs), GFP_KERNEL);
         if (!cookies) {
             err = -ENOMEM;
             goto error;
         }
         if (copy_from_user(cookies, ucookies, size)) {
             err = -EFAULT;
             goto error;
         }
     }
 
     if (uaddrs) {
         if (copy_from_user(addrs, uaddrs, size)) {
             err = -EFAULT;
             goto error;
         }
     } else {
         struct multi_symbols_sort data = {
             .cookies = cookies,
         };
         struct user_syms us;
 
         err = copy_user_syms(&us, usyms, cnt);
         if (err)
             goto error;
 
         if (cookies)
             data.funcs = us.syms;
 
         sort_r(us.syms, cnt, sizeof(*us.syms), symbols_cmp_r,
                symbols_swap_r, &data);
 
         err = ftrace_lookup_symbols(us.syms, cnt, addrs);
         free_user_syms(&us);
         if (err)
             goto error;
     }
 
     link = kzalloc(sizeof(*link), GFP_KERNEL);
     if (!link) {
         err = -ENOMEM;
         goto error;
     }
 
     bpf_link_init(&link->link, BPF_LINK_TYPE_KPROBE_MULTI,
               &bpf_kprobe_multi_link_lops, prog);
 
     err = bpf_link_prime(&link->link, &link_primer);
     if (err)
         goto error;
 
     if (flags & BPF_F_KPROBE_MULTI_RETURN)
         link->fp.exit_handler = kprobe_multi_link_handler;
     else
         link->fp.entry_handler = kprobe_multi_link_handler;
 
     link->addrs = addrs;
     link->cookies = cookies;
     link->cnt = cnt;
 
     if (cookies) {
         /*
          * Sorting addresses will trigger sorting cookies as well
          * (check bpf_kprobe_multi_cookie_swap). This way we can
          * find cookie based on the address in bpf_get_attach_cookie
          * helper.
          */
         sort_r(addrs, cnt, sizeof(*addrs),
                bpf_kprobe_multi_cookie_cmp,
                bpf_kprobe_multi_cookie_swap,
                link);
     }
 
     err = register_fprobe_ips(&link->fp, addrs, cnt);
     if (err) {
         bpf_link_cleanup(&link_primer);
         return err;
     }
 
     return bpf_link_settle(&link_primer);
 
 error:
     kfree(link);
     kvfree(addrs);
     kvfree(cookies);
     return err;
 }
 #else /* !CONFIG_FPROBE */
 int bpf_kprobe_multi_link_attach(const union bpf_attr *attr, struct bpf_prog *prog)
 {
     return -EOPNOTSUPP;
 }
 static u64 bpf_kprobe_multi_cookie(struct bpf_run_ctx *ctx)
 {
     return 0;
 }
 static u64 bpf_kprobe_multi_entry_ip(struct bpf_run_ctx *ctx)
 {
     return 0;
 }
 #endif