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// SPDX-License-Identifier: GPL-2.0
/* Copyright (c) 2026 Meta Platforms, Inc. and affiliates. */
#include <vmlinux.h>
#include <bpf/bpf_helpers.h>
#include <bpf/bpf_tracing.h>
#include "../test_kmods/bpf_testmod_kfunc.h"
struct map_value {
struct prog_test_ref_kfunc __kptr *ref_ptr;
};
struct {
__uint(type, BPF_MAP_TYPE_HASH);
__uint(map_flags, BPF_F_NO_PREALLOC);
__type(key, int);
__type(value, struct map_value);
__uint(max_entries, 1);
} race_hash_map SEC(".maps");
struct {
__uint(type, BPF_MAP_TYPE_PERCPU_HASH);
__uint(map_flags, BPF_F_NO_PREALLOC);
__type(key, int);
__type(value, struct map_value);
__uint(max_entries, 1);
} race_percpu_hash_map SEC(".maps");
struct {
__uint(type, BPF_MAP_TYPE_SK_STORAGE);
__uint(map_flags, BPF_F_NO_PREALLOC);
__type(key, int);
__type(value, struct map_value);
} race_sk_ls_map SEC(".maps");
int num_of_refs;
int sk_ls_leak_done;
int target_map_id;
int map_freed;
const volatile int nr_cpus;
SEC("tc")
int test_htab_leak(struct __sk_buff *skb)
{
struct prog_test_ref_kfunc *p, *old;
struct map_value val = {};
struct map_value *v;
int key = 0;
if (bpf_map_update_elem(&race_hash_map, &key, &val, BPF_ANY))
return 1;
v = bpf_map_lookup_elem(&race_hash_map, &key);
if (!v)
return 2;
p = bpf_kfunc_call_test_acquire(&(unsigned long){0});
if (!p)
return 3;
old = bpf_kptr_xchg(&v->ref_ptr, p);
if (old)
bpf_kfunc_call_test_release(old);
bpf_map_delete_elem(&race_hash_map, &key);
p = bpf_kfunc_call_test_acquire(&(unsigned long){0});
if (!p)
return 4;
old = bpf_kptr_xchg(&v->ref_ptr, p);
if (old)
bpf_kfunc_call_test_release(old);
return 0;
}
static int fill_percpu_kptr(struct map_value *v)
{
struct prog_test_ref_kfunc *p, *old;
p = bpf_kfunc_call_test_acquire(&(unsigned long){0});
if (!p)
return 1;
old = bpf_kptr_xchg(&v->ref_ptr, p);
if (old)
bpf_kfunc_call_test_release(old);
return 0;
}
SEC("tc")
int test_percpu_htab_leak(struct __sk_buff *skb)
{
struct map_value *v, *arr[16] = {};
struct map_value val = {};
int key = 0;
int err = 0;
if (bpf_map_update_elem(&race_percpu_hash_map, &key, &val, BPF_ANY))
return 1;
for (int i = 0; i < nr_cpus; i++) {
v = bpf_map_lookup_percpu_elem(&race_percpu_hash_map, &key, i);
if (!v)
return 2;
arr[i] = v;
}
bpf_map_delete_elem(&race_percpu_hash_map, &key);
for (int i = 0; i < nr_cpus; i++) {
v = arr[i];
err = fill_percpu_kptr(v);
if (err)
return 3;
}
return 0;
}
SEC("tp_btf/inet_sock_set_state")
int BPF_PROG(test_sk_ls_leak, struct sock *sk, int oldstate, int newstate)
{
struct prog_test_ref_kfunc *p, *old;
struct map_value *v;
if (newstate != BPF_TCP_SYN_SENT)
return 0;
if (sk_ls_leak_done)
return 0;
v = bpf_sk_storage_get(&race_sk_ls_map, sk, NULL,
BPF_SK_STORAGE_GET_F_CREATE);
if (!v)
return 0;
p = bpf_kfunc_call_test_acquire(&(unsigned long){0});
if (!p)
return 0;
old = bpf_kptr_xchg(&v->ref_ptr, p);
if (old)
bpf_kfunc_call_test_release(old);
bpf_sk_storage_delete(&race_sk_ls_map, sk);
p = bpf_kfunc_call_test_acquire(&(unsigned long){0});
if (!p)
return 0;
old = bpf_kptr_xchg(&v->ref_ptr, p);
if (old)
bpf_kfunc_call_test_release(old);
sk_ls_leak_done = 1;
return 0;
}
long target_map_ptr;
SEC("fentry/bpf_map_put")
int BPF_PROG(map_put, struct bpf_map *map)
{
if (target_map_id && map->id == (u32)target_map_id)
target_map_ptr = (long)map;
return 0;
}
SEC("fexit/htab_map_free")
int BPF_PROG(htab_map_free, struct bpf_map *map)
{
if (target_map_ptr && (long)map == target_map_ptr)
map_freed = 1;
return 0;
}
SEC("fexit/bpf_sk_storage_map_free")
int BPF_PROG(sk_map_free, struct bpf_map *map)
{
if (target_map_ptr && (long)map == target_map_ptr)
map_freed = 1;
return 0;
}
SEC("syscall")
int count_ref(void *ctx)
{
struct prog_test_ref_kfunc *p;
unsigned long arg = 0;
p = bpf_kfunc_call_test_acquire(&arg);
if (!p)
return 1;
num_of_refs = p->cnt.refs.counter;
bpf_kfunc_call_test_release(p);
return 0;
}
char _license[] SEC("license") = "GPL";
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