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 9 void *sk_ptr = NULL; 10 int cookie_found = 0; 11 __u64 cookie = 0; 12 __u32 omem = 0; 13 14 struct { 15 __uint(type, BPF_MAP_TYPE_SK_STORAGE); 16 __uint(map_flags, BPF_F_NO_PREALLOC); 17 __type(key, int); 18 __type(value, int); 19 } sk_storage SEC(".maps"); 20 21 SEC("fexit/bpf_sk_storage_free") 22 int BPF_PROG(bpf_sk_storage_free, struct sock *sk) 23 { 24 if (sk_ptr != sk) 25 return 0; 26 27 if (sk->sk_cookie.counter != cookie) 28 return 0; 29 30 cookie_found++; 31 omem = sk->sk_omem_alloc.counter; 32 33 return 0; 34 } 35 36 SEC("fentry/inet6_sock_destruct") 37 int BPF_PROG(inet6_sock_destruct, struct sock *sk) 38 { 39 int *value; 40 41 if (!cookie || sk->sk_cookie.counter != cookie) 42 return 0; 43 44 value = bpf_sk_storage_get(&sk_storage, sk, 0, 0); 45 if (value && *value == 0xdeadbeef) { 46 cookie_found++; 47 sk_ptr = sk; 48 } 49 50 return 0; 51 } 52 53 char _license[] SEC("license") = "GPL"; 54