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1// SPDX-License-Identifier: GPL-2.02/* Copyright (c) 2023 Facebook */3#include "vmlinux.h"4#include "bpf_tracing_net.h"5#include <bpf/bpf_helpers.h>6#include <bpf/bpf_tracing.h>7#include <bpf/bpf_core_read.h>8 9void *local_storage_ptr = NULL;10void *sk_ptr = NULL;11int cookie_found = 0;12__u64 cookie = 0;13__u32 omem = 0;14 15struct {16 __uint(type, BPF_MAP_TYPE_SK_STORAGE);17 __uint(map_flags, BPF_F_NO_PREALLOC);18 __type(key, int);19 __type(value, int);20} sk_storage SEC(".maps");21 22SEC("fexit/bpf_local_storage_destroy")23int BPF_PROG(bpf_local_storage_destroy, struct bpf_local_storage *local_storage)24{25 struct sock *sk;26 27 if (local_storage_ptr != local_storage)28 return 0;29 30 sk = bpf_core_cast(sk_ptr, struct sock);31 if (sk->sk_cookie.counter != cookie)32 return 0;33 34 cookie_found++;35 omem = sk->sk_omem_alloc.counter;36 local_storage_ptr = NULL;37 38 return 0;39}40 41SEC("fentry/inet6_sock_destruct")42int BPF_PROG(inet6_sock_destruct, struct sock *sk)43{44 int *value;45 46 if (!cookie || sk->sk_cookie.counter != cookie)47 return 0;48 49 value = bpf_sk_storage_get(&sk_storage, sk, 0, 0);50 if (value && *value == 0xdeadbeef) {51 cookie_found++;52 sk_ptr = sk;53 local_storage_ptr = sk->sk_bpf_storage;54 }55 56 return 0;57}58 59char _license[] SEC("license") = "GPL";60