70 lines
1.5 KiB
C
70 lines
1.5 KiB
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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#include <bpf/bpf_tracing.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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#define VM_EXEC 0x00000004
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#define DNAME_INLINE_LEN 32
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pid_t target_pid = 0;
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char d_iname[DNAME_INLINE_LEN] = {0};
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__u32 found_vm_exec = 0;
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__u64 addr = 0;
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int find_zero_ret = -1;
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int find_addr_ret = -1;
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static long check_vma(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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if (vma->vm_file)
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bpf_probe_read_kernel_str(d_iname, DNAME_INLINE_LEN - 1,
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vma->vm_file->f_path.dentry->d_iname);
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/* check for VM_EXEC */
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if (vma->vm_flags & VM_EXEC)
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found_vm_exec = 1;
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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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if (task->pid != target_pid)
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return 0;
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find_addr_ret = bpf_find_vma(task, addr, check_vma, &data, 0);
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/* this should return -ENOENT */
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find_zero_ret = bpf_find_vma(task, 0, check_vma, &data, 0);
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return 0;
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}
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SEC("perf_event")
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int handle_pe(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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if (task->pid != target_pid)
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return 0;
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find_addr_ret = bpf_find_vma(task, addr, check_vma, &data, 0);
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/* In NMI, this should return -EBUSY, as the previous call is using
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* the irq_work.
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*/
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find_zero_ret = bpf_find_vma(task, 0, check_vma, &data, 0);
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return 0;
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}
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