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// SPDX-License-Identifier: GPL-2.0
#include <vmlinux.h>
#include <bpf/bpf_tracing.h>
#include <bpf/bpf_helpers.h>
#include "bpf_experimental.h"
struct foo {
struct bpf_spin_lock lock;
int data;
};
struct array_map {
__uint(type, BPF_MAP_TYPE_ARRAY);
__type(key, int);
__type(value, struct foo);
__uint(max_entries, 1);
} array_map SEC(".maps");
struct {
__uint(type, BPF_MAP_TYPE_ARRAY_OF_MAPS);
__uint(max_entries, 1);
__type(key, int);
__type(value, int);
__array(values, struct array_map);
} map_of_maps SEC(".maps") = {
.values = {
[0] = &array_map,
},
};
SEC(".data.A") struct bpf_spin_lock lockA;
SEC(".data.B") struct bpf_spin_lock lockB;
SEC("?tc")
int lock_id_kptr_preserve(void *ctx)
{
struct foo *f;
f = bpf_obj_new(typeof(*f));
if (!f)
return 0;
bpf_this_cpu_ptr(f);
return 0;
}
SEC("?tc")
int lock_id_global_zero(void *ctx)
{
bpf_this_cpu_ptr(&lockA);
return 0;
}
SEC("?tc")
int lock_id_mapval_preserve(void *ctx)
{
struct foo *f;
int key = 0;
f = bpf_map_lookup_elem(&array_map, &key);
if (!f)
return 0;
bpf_this_cpu_ptr(f);
return 0;
}
SEC("?tc")
int lock_id_innermapval_preserve(void *ctx)
{
struct foo *f;
int key = 0;
void *map;
map = bpf_map_lookup_elem(&map_of_maps, &key);
if (!map)
return 0;
f = bpf_map_lookup_elem(map, &key);
if (!f)
return 0;
bpf_this_cpu_ptr(f);
return 0;
}
#define CHECK(test, A, B) \
SEC("?tc") \
int lock_id_mismatch_##test(void *ctx) \
{ \
struct foo *f1, *f2, *v, *iv; \
int key = 0; \
void *map; \
\
map = bpf_map_lookup_elem(&map_of_maps, &key); \
if (!map) \
return 0; \
iv = bpf_map_lookup_elem(map, &key); \
if (!iv) \
return 0; \
v = bpf_map_lookup_elem(&array_map, &key); \
if (!v) \
return 0; \
f1 = bpf_obj_new(typeof(*f1)); \
if (!f1) \
return 0; \
f2 = bpf_obj_new(typeof(*f2)); \
if (!f2) { \
bpf_obj_drop(f1); \
return 0; \
} \
bpf_spin_lock(A); \
bpf_spin_unlock(B); \
return 0; \
}
CHECK(kptr_kptr, &f1->lock, &f2->lock);
CHECK(kptr_global, &f1->lock, &lockA);
CHECK(kptr_mapval, &f1->lock, &v->lock);
CHECK(kptr_innermapval, &f1->lock, &iv->lock);
CHECK(global_global, &lockA, &lockB);
CHECK(global_kptr, &lockA, &f1->lock);
CHECK(global_mapval, &lockA, &v->lock);
CHECK(global_innermapval, &lockA, &iv->lock);
SEC("?tc")
int lock_id_mismatch_mapval_mapval(void *ctx)
{
struct foo *f1, *f2;
int key = 0;
f1 = bpf_map_lookup_elem(&array_map, &key);
if (!f1)
return 0;
f2 = bpf_map_lookup_elem(&array_map, &key);
if (!f2)
return 0;
bpf_spin_lock(&f1->lock);
f1->data = 42;
bpf_spin_unlock(&f2->lock);
return 0;
}
CHECK(mapval_kptr, &v->lock, &f1->lock);
CHECK(mapval_global, &v->lock, &lockB);
CHECK(mapval_innermapval, &v->lock, &iv->lock);
SEC("?tc")
int lock_id_mismatch_innermapval_innermapval1(void *ctx)
{
struct foo *f1, *f2;
int key = 0;
void *map;
map = bpf_map_lookup_elem(&map_of_maps, &key);
if (!map)
return 0;
f1 = bpf_map_lookup_elem(map, &key);
if (!f1)
return 0;
f2 = bpf_map_lookup_elem(map, &key);
if (!f2)
return 0;
bpf_spin_lock(&f1->lock);
f1->data = 42;
bpf_spin_unlock(&f2->lock);
return 0;
}
SEC("?tc")
int lock_id_mismatch_innermapval_innermapval2(void *ctx)
{
struct foo *f1, *f2;
int key = 0;
void *map;
map = bpf_map_lookup_elem(&map_of_maps, &key);
if (!map)
return 0;
f1 = bpf_map_lookup_elem(map, &key);
if (!f1)
return 0;
map = bpf_map_lookup_elem(&map_of_maps, &key);
if (!map)
return 0;
f2 = bpf_map_lookup_elem(map, &key);
if (!f2)
return 0;
bpf_spin_lock(&f1->lock);
f1->data = 42;
bpf_spin_unlock(&f2->lock);
return 0;
}
CHECK(innermapval_kptr, &iv->lock, &f1->lock);
CHECK(innermapval_global, &iv->lock, &lockA);
CHECK(innermapval_mapval, &iv->lock, &v->lock);
#undef CHECK
__noinline
int global_subprog(struct __sk_buff *ctx)
{
volatile int ret = 0;
if (ctx->protocol)
ret += ctx->protocol;
return ret + ctx->mark;
}
__noinline
static int static_subprog_call_global(struct __sk_buff *ctx)
{
volatile int ret = 0;
if (ctx->protocol)
return ret;
return ret + ctx->len + global_subprog(ctx);
}
SEC("?tc")
int lock_global_subprog_call1(struct __sk_buff *ctx)
{
int ret = 0;
bpf_spin_lock(&lockA);
if (ctx->mark == 42)
ret = global_subprog(ctx);
bpf_spin_unlock(&lockA);
return ret;
}
SEC("?tc")
int lock_global_subprog_call2(struct __sk_buff *ctx)
{
int ret = 0;
bpf_spin_lock(&lockA);
if (ctx->mark == 42)
ret = static_subprog_call_global(ctx);
bpf_spin_unlock(&lockA);
return ret;
}
char _license[] SEC("license") = "GPL";
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