30 lines
587 B
C
30 lines
587 B
C
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// SPDX-License-Identifier: GPL-2.0
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/* Copyright (c) 2021 Facebook */
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#include "vmlinux.h"
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#include <bpf/bpf_helpers.h>
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char _license[] SEC("license") = "GPL";
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struct callback_ctx {
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int dummy;
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};
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static long write_task(struct task_struct *task, struct vm_area_struct *vma,
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struct callback_ctx *data)
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{
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/* writing to task, which is illegal */
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task->mm = NULL;
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return 0;
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}
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SEC("raw_tp/sys_enter")
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int handle_getpid(void)
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{
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struct task_struct *task = bpf_get_current_task_btf();
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struct callback_ctx data = {};
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bpf_find_vma(task, 0, write_task, &data, 0);
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return 0;
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}
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