1169691Skan// SPDX-License-Identifier: GPL-2.0 2169691Skan 3169691Skan#include "vmlinux.h" 4169691Skan#include <bpf/bpf_helpers.h> 5169691Skan#include <bpf/bpf_tracing.h> 6169691Skan 7169691Skanchar _license[] SEC("license") = "GPL"; 8169691Skan 9169691Skan#ifndef EBUSY 10169691Skan#define EBUSY 16 11169691Skan#endif 12169691Skan 13169691Skanextern bool CONFIG_PREEMPT __kconfig __weak; 14169691Skanint nr_get_errs = 0; 15169691Skanint nr_del_errs = 0; 16169691Skan 17169691Skanstruct { 18169691Skan __uint(type, BPF_MAP_TYPE_TASK_STORAGE); 19169691Skan __uint(map_flags, BPF_F_NO_PREALLOC); 20169691Skan __type(key, int); 21169691Skan __type(value, int); 22169691Skan} task_storage SEC(".maps"); 23169691Skan 24169691SkanSEC("lsm.s/socket_post_create") 25169691Skanint BPF_PROG(socket_post_create, struct socket *sock, int family, int type, 26169691Skan int protocol, int kern) 27169691Skan{ 28169691Skan struct task_struct *task; 29169691Skan int ret, zero = 0; 30169691Skan int *value; 31169691Skan 32169691Skan if (!CONFIG_PREEMPT) 33169691Skan return 0; 34169691Skan 35169691Skan task = bpf_get_current_task_btf(); 36169691Skan value = bpf_task_storage_get(&task_storage, task, &zero, 37169691Skan BPF_LOCAL_STORAGE_GET_F_CREATE); 38169691Skan if (!value) 39169691Skan __sync_fetch_and_add(&nr_get_errs, 1); 40169691Skan 41169691Skan ret = bpf_task_storage_delete(&task_storage, 42169691Skan bpf_get_current_task_btf()); 43169691Skan if (ret == -EBUSY) 44169691Skan __sync_fetch_and_add(&nr_del_errs, 1); 45169691Skan 46169691Skan return 0; 47169691Skan} 48169691Skan