cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
Log | Files | Refs | README | LICENSE | sfeed.txt

test_perf_buffer.c (884B)

      1// SPDX-License-Identifier: GPL-2.0
      2// Copyright (c) 2019 Facebook
      3
      4#include <linux/ptrace.h>
      5#include <linux/bpf.h>
      6#include <bpf/bpf_helpers.h>
      7#include <bpf/bpf_tracing.h>
      8
      9struct {
     10	__uint(type, BPF_MAP_TYPE_ARRAY);
     11	__type(key, int);
     12	__type(value, int);
     13	__uint(max_entries, 1);
     14} my_pid_map SEC(".maps");
     15
     16struct {
     17	__uint(type, BPF_MAP_TYPE_PERF_EVENT_ARRAY);
     18	__type(key, int);
     19	__type(value, int);
     20} perf_buf_map SEC(".maps");
     21
     22SEC("tp/raw_syscalls/sys_enter")
     23int handle_sys_enter(void *ctx)
     24{
     25	int zero = 0, *my_pid, cur_pid;
     26	int cpu = bpf_get_smp_processor_id();
     27
     28	my_pid = bpf_map_lookup_elem(&my_pid_map, &zero);
     29	if (!my_pid)
     30		return 1;
     31
     32	cur_pid = bpf_get_current_pid_tgid() >> 32;
     33	if (cur_pid != *my_pid)
     34		return 1;
     35
     36	bpf_perf_event_output(ctx, &perf_buf_map, BPF_F_CURRENT_CPU,
     37			      &cpu, sizeof(cpu));
     38	return 1;
     39}
     40
     41char _license[] SEC("license") = "GPL";