Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1// SPDX-License-Identifier: GPL-2.0
2/* Copyright (c) 2025 Meta Platforms, Inc. and affiliates. */
3
4#include <vmlinux.h>
5#include <string.h>
6#include <stdbool.h>
7#include <bpf/bpf_helpers.h>
8#include <bpf/bpf_tracing.h>
9#include "bpf_misc.h"
10
11char _license[] SEC("license") = "GPL";
12
13const void *user_ptr = NULL;
14
15struct elem {
16 char data[128];
17 struct bpf_task_work tw;
18};
19
20struct {
21 __uint(type, BPF_MAP_TYPE_HASH);
22 __uint(map_flags, BPF_F_NO_PREALLOC);
23 __uint(max_entries, 1);
24 __type(key, int);
25 __type(value, struct elem);
26} hmap SEC(".maps");
27
28struct {
29 __uint(type, BPF_MAP_TYPE_ARRAY);
30 __uint(max_entries, 1);
31 __type(key, int);
32 __type(value, struct elem);
33} arrmap SEC(".maps");
34
35static int process_work(struct bpf_map *map, void *key, void *value)
36{
37 struct elem *work = value;
38
39 bpf_copy_from_user_str(work->data, sizeof(work->data), (const void *)user_ptr, 0);
40 return 0;
41}
42
43int key = 0;
44
45SEC("perf_event")
46__failure __msg("doesn't match map pointer in R3")
47int mismatch_map(struct pt_regs *args)
48{
49 struct elem *work;
50 struct task_struct *task;
51
52 task = bpf_get_current_task_btf();
53 work = bpf_map_lookup_elem(&arrmap, &key);
54 if (!work)
55 return 0;
56 bpf_task_work_schedule_resume(task, &work->tw, &hmap, process_work);
57 return 0;
58}
59
60SEC("perf_event")
61__failure __msg("arg#1 doesn't point to a map value")
62int no_map_task_work(struct pt_regs *args)
63{
64 struct task_struct *task;
65 struct bpf_task_work tw;
66
67 task = bpf_get_current_task_btf();
68 bpf_task_work_schedule_resume(task, &tw, &hmap, process_work);
69 return 0;
70}
71
72SEC("perf_event")
73__failure __msg("Possibly NULL pointer passed to trusted arg1")
74int task_work_null(struct pt_regs *args)
75{
76 struct task_struct *task;
77
78 task = bpf_get_current_task_btf();
79 bpf_task_work_schedule_resume(task, NULL, &hmap, process_work);
80 return 0;
81}
82
83SEC("perf_event")
84__failure __msg("Possibly NULL pointer passed to trusted arg2")
85int map_null(struct pt_regs *args)
86{
87 struct elem *work;
88 struct task_struct *task;
89
90 task = bpf_get_current_task_btf();
91 work = bpf_map_lookup_elem(&arrmap, &key);
92 if (!work)
93 return 0;
94 bpf_task_work_schedule_resume(task, &work->tw, NULL, process_work);
95 return 0;
96}