// SPDX-License-Identifier: GPL-2.0 /* Copyright (c) 2022 Meta Platforms, Inc. and affiliates. */ #include "vmlinux.h" #include <bpf/bpf_helpers.h> #include <bpf/bpf_tracing.h> char _license[] SEC("license") = "GPL"; struct { __uint(type, BPF_MAP_TYPE_CGRP_STORAGE); __uint(map_flags, BPF_F_NO_PREALLOC); __type(key, int); __type(value, long); } map_a SEC(".maps"); struct { __uint(type, BPF_MAP_TYPE_CGRP_STORAGE); __uint(map_flags, BPF_F_NO_PREALLOC); __type(key, int); __type(value, long); } map_b SEC(".maps"); #define MAGIC_VALUE 0xabcd1234 pid_t target_pid = 0; int mismatch_cnt = 0; int enter_cnt = 0; int exit_cnt = 0; SEC("tp_btf/sys_enter") int BPF_PROG(on_enter, struct pt_regs *regs, long id) { struct task_struct *task; long *ptr; int err; task = bpf_get_current_task_btf(); if (task->pid != target_pid) return 0; /* populate value 0 */ ptr = bpf_cgrp_storage_get(&map_a, task->cgroups->dfl_cgrp, 0, BPF_LOCAL_STORAGE_GET_F_CREATE); if (!ptr) return 0; /* delete value 0 */ err = bpf_cgrp_storage_delete(&map_a, task->cgroups->dfl_cgrp); if (err) return 0; /* value is not available */ ptr = bpf_cgrp_storage_get(&map_a, task->cgroups->dfl_cgrp, 0, 0); if (ptr) return 0; /* re-populate the value */ ptr = bpf_cgrp_storage_get(&map_a, task->cgroups->dfl_cgrp, 0, BPF_LOCAL_STORAGE_GET_F_CREATE); if (!ptr) return 0; __sync_fetch_and_add(&enter_cnt, 1); *ptr = MAGIC_VALUE + enter_cnt; return 0; } SEC("tp_btf/sys_exit") int BPF_PROG(on_exit, struct pt_regs *regs, long id) { struct task_struct *task; long *ptr; task = bpf_get_current_task_btf(); if (task->pid != target_pid) return 0; ptr = bpf_cgrp_storage_get(&map_a, task->cgroups->dfl_cgrp, 0, BPF_LOCAL_STORAGE_GET_F_CREATE); if (!ptr) return 0; __sync_fetch_and_add(&exit_cnt, 1); if (*ptr != MAGIC_VALUE + exit_cnt) __sync_fetch_and_add(&mismatch_cnt, 1); return 0; }