97 lines
2.1 KiB
C
97 lines
2.1 KiB
C
// SPDX-License-Identifier: GPL-2.0
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/* Copyright (c) 2025 Meta Platforms, Inc. and affiliates. */
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#include <vmlinux.h>
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#include <string.h>
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#include <stdbool.h>
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#include <bpf/bpf_helpers.h>
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#include <bpf/bpf_tracing.h>
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#include "bpf_misc.h"
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char _license[] SEC("license") = "GPL";
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const void *user_ptr = NULL;
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struct elem {
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char data[128];
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struct bpf_task_work tw;
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};
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struct {
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__uint(type, BPF_MAP_TYPE_HASH);
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__uint(map_flags, BPF_F_NO_PREALLOC);
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__uint(max_entries, 1);
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__type(key, int);
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__type(value, struct elem);
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} hmap SEC(".maps");
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struct {
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__uint(type, BPF_MAP_TYPE_ARRAY);
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__uint(max_entries, 1);
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__type(key, int);
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__type(value, struct elem);
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} arrmap SEC(".maps");
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static int process_work(struct bpf_map *map, void *key, void *value)
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{
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struct elem *work = value;
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bpf_copy_from_user_str(work->data, sizeof(work->data), (const void *)user_ptr, 0);
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return 0;
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}
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int key = 0;
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SEC("perf_event")
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__failure __msg("doesn't match map pointer in R3")
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int mismatch_map(struct pt_regs *args)
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{
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struct elem *work;
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struct task_struct *task;
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task = bpf_get_current_task_btf();
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work = bpf_map_lookup_elem(&arrmap, &key);
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if (!work)
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return 0;
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bpf_task_work_schedule_resume_impl(task, &work->tw, &hmap, process_work, NULL);
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return 0;
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}
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SEC("perf_event")
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__failure __msg("arg#1 doesn't point to a map value")
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int no_map_task_work(struct pt_regs *args)
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{
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struct task_struct *task;
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struct bpf_task_work tw;
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task = bpf_get_current_task_btf();
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bpf_task_work_schedule_resume_impl(task, &tw, &hmap, process_work, NULL);
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return 0;
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}
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SEC("perf_event")
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__failure __msg("Possibly NULL pointer passed to trusted arg1")
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int task_work_null(struct pt_regs *args)
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{
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struct task_struct *task;
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task = bpf_get_current_task_btf();
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bpf_task_work_schedule_resume_impl(task, NULL, &hmap, process_work, NULL);
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return 0;
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}
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SEC("perf_event")
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__failure __msg("Possibly NULL pointer passed to trusted arg2")
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int map_null(struct pt_regs *args)
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{
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struct elem *work;
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struct task_struct *task;
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task = bpf_get_current_task_btf();
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work = bpf_map_lookup_elem(&arrmap, &key);
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if (!work)
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return 0;
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bpf_task_work_schedule_resume_impl(task, &work->tw, NULL, process_work, NULL);
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return 0;
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}
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