diff options
Diffstat (limited to 'tools/testing/selftests/bpf/progs/map_kptr_race.c')
| -rw-r--r-- | tools/testing/selftests/bpf/progs/map_kptr_race.c | 197 |
1 files changed, 197 insertions, 0 deletions
diff --git a/tools/testing/selftests/bpf/progs/map_kptr_race.c b/tools/testing/selftests/bpf/progs/map_kptr_race.c new file mode 100644 index 000000000000..f6f136cd8f60 --- /dev/null +++ b/tools/testing/selftests/bpf/progs/map_kptr_race.c @@ -0,0 +1,197 @@ +// 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"; |