1// SPDX-License-Identifier: GPL-2.0 2/* 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