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// SPDX-License-Identifier: GPL-2.0
/* Copyright (c) 2022 Meta Platforms, Inc. and affiliates. */
#include <linux/bpf.h>
#include <bpf/bpf_helpers.h>
#include <bpf/bpf_core_read.h>
struct task_struct___bad {
int pid;
int fake_field;
void *fake_field_subprog;
} __attribute__((preserve_access_index));
SEC("?raw_tp/sys_enter")
int bad_relo(const void *ctx)
{
static struct task_struct___bad *t;
return bpf_core_field_size(t->fake_field);
}
static __noinline int bad_subprog(void)
{
static struct task_struct___bad *t;
/* ugliness below is a field offset relocation */
return (void *)&t->fake_field_subprog - (void *)t;
}
SEC("?raw_tp/sys_enter")
int bad_relo_subprog(const void *ctx)
{
static struct task_struct___bad *t;
return bad_subprog() + bpf_core_field_size(t->pid);
}
struct {
__uint(type, BPF_MAP_TYPE_ARRAY);
__uint(max_entries, 1);
__type(key, int);
__type(value, int);
} existing_map SEC(".maps");
struct {
__uint(type, BPF_MAP_TYPE_ARRAY);
__uint(max_entries, 1);
__type(key, int);
__type(value, int);
} missing_map SEC(".maps");
SEC("?raw_tp/sys_enter")
int use_missing_map(const void *ctx)
{
int zero = 0, *value;
value = bpf_map_lookup_elem(&existing_map, &zero);
value = bpf_map_lookup_elem(&missing_map, &zero);
return value != NULL;
}
char _license[] SEC("license") = "GPL";
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