1 // SPDX-License-Identifier: GPL-2.0
2 /* Copyright (c) 2024 Meta Platforms, Inc. and affiliates. */
3
4 #define BPF_NO_KFUNC_PROTOTYPES
5 #include <vmlinux.h>
6 #include <bpf/bpf_helpers.h>
7 #include <bpf/bpf_tracing.h>
8 #include "bpf_misc.h"
9 #include "bpf_experimental.h"
10 #include "bpf_arena_common.h"
11
12 #define ARENA_SIZE (1ull << 32)
13
14 struct {
15 __uint(type, BPF_MAP_TYPE_ARENA);
16 __uint(map_flags, BPF_F_MMAPABLE);
17 __uint(max_entries, ARENA_SIZE / PAGE_SIZE);
18 } arena SEC(".maps");
19
20 SEC("syscall")
21 __success __retval(0)
22 int big_alloc1(void *ctx)
23 {
24 #if defined(__BPF_FEATURE_ADDR_SPACE_CAST)
25 volatile char __arena *page1, *page2, *no_page, *page3;
26 void __arena *base;
27
28 page1 = base = bpf_arena_alloc_pages(&arena, NULL, 1, NUMA_NO_NODE, 0);
29 if (!page1)
30 return 1;
31 *page1 = 1;
32 page2 = bpf_arena_alloc_pages(&arena, base + ARENA_SIZE - PAGE_SIZE,
33 1, NUMA_NO_NODE, 0);
34 if (!page2)
35 return 2;
36 *page2 = 2;
37 no_page = bpf_arena_alloc_pages(&arena, base + ARENA_SIZE,
38 1, NUMA_NO_NODE, 0);
39 if (no_page)
40 return 3;
41 if (*page1 != 1)
42 return 4;
43 if (*page2 != 2)
44 return 5;
45 bpf_arena_free_pages(&arena, (void __arena *)page1, 1);
46 if (*page2 != 2)
47 return 6;
48 if (*page1 != 0) /* use-after-free should return 0 */
49 return 7;
50 page3 = bpf_arena_alloc_pages(&arena, NULL, 1, NUMA_NO_NODE, 0);
51 if (!page3)
52 return 8;
53 *page3 = 3;
54 if (page1 != page3)
55 return 9;
56 if (*page2 != 2)
57 return 10;
58 if (*(page1 + PAGE_SIZE) != 0)
59 return 11;
60 if (*(page1 - PAGE_SIZE) != 0)
61 return 12;
62 if (*(page2 + PAGE_SIZE) != 0)
63 return 13;
64 if (*(page2 - PAGE_SIZE) != 0)
65 return 14;
66 #endif
67 return 0;
68 }
69 char _license[] SEC("license") = "GPL";
70
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