// SPDX-License-Identifier: GPL-2.0
/* Copyright (c) 2021 Facebook */
#include "vmlinux.h"
#include <bpf/bpf_helpers.h>
#include <bpf/bpf_tracing.h>
char _license[] SEC("license") = "GPL";
struct callback_ctx {
int dummy;
};
#define VM_EXEC 0x00000004
#define DNAME_INLINE_LEN 32
pid_t target_pid = 0;
char d_iname[DNAME_INLINE_LEN] = {0};
__u32 found_vm_exec = 0;
__u64 addr = 0;
int find_zero_ret = -1;
int find_addr_ret = -1;
static long check_vma(struct task_struct *task, struct vm_area_struct *vma,
struct callback_ctx *data)
{
if (vma->vm_file)
bpf_probe_read_kernel_str(d_iname, DNAME_INLINE_LEN - 1,
vma->vm_file->f_path.dentry->d_iname);
/* check for VM_EXEC */
if (vma->vm_flags & VM_EXEC)
found_vm_exec = 1;
return 0;
}
SEC("raw_tp/sys_enter")
int handle_getpid(void)
{
struct task_struct *task = bpf_get_current_task_btf();
struct callback_ctx data = {};
if (task->pid != target_pid)
return 0;
find_addr_ret = bpf_find_vma(task, addr, check_vma, &data, 0);
/* this should return -ENOENT */
find_zero_ret = bpf_find_vma(task, 0, check_vma, &data, 0);
return 0;
}
SEC("perf_event")
int handle_pe(void)
{
struct task_struct *task = bpf_get_current_task_btf();
struct callback_ctx data = {};
if (task->pid != target_pid)
return 0;
find_addr_ret = bpf_find_vma(task, addr, check_vma, &data, 0);
/* In NMI, this should return -EBUSY, as the previous call is using
* the irq_work.
*/
find_zero_ret = bpf_find_vma(task, 0, check_vma, &data, 0);
return 0;
}