diff options
Diffstat (limited to 'tools/testing/selftests/bpf/progs/verifier_arena_large.c')
| -rw-r--r-- | tools/testing/selftests/bpf/progs/verifier_arena_large.c | 175 |
1 files changed, 175 insertions, 0 deletions
diff --git a/tools/testing/selftests/bpf/progs/verifier_arena_large.c b/tools/testing/selftests/bpf/progs/verifier_arena_large.c new file mode 100644 index 000000000000..f94f30cf1bb8 --- /dev/null +++ b/tools/testing/selftests/bpf/progs/verifier_arena_large.c @@ -0,0 +1,175 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright (c) 2024 Meta Platforms, Inc. and affiliates. */ + +#define BPF_NO_KFUNC_PROTOTYPES +#include <vmlinux.h> +#include <bpf/bpf_helpers.h> +#include <bpf/bpf_tracing.h> +#include "bpf_misc.h" +#include "bpf_experimental.h" +#include "bpf_arena_common.h" + +#define ARENA_SIZE (1ull << 32) + +struct { + __uint(type, BPF_MAP_TYPE_ARENA); + __uint(map_flags, BPF_F_MMAPABLE); + __uint(max_entries, ARENA_SIZE / PAGE_SIZE); +} arena SEC(".maps"); + +SEC("syscall") +__success __retval(0) +int big_alloc1(void *ctx) +{ +#if defined(__BPF_FEATURE_ADDR_SPACE_CAST) + volatile char __arena *page1, *page2, *no_page, *page3; + void __arena *base; + + page1 = base = bpf_arena_alloc_pages(&arena, NULL, 1, NUMA_NO_NODE, 0); + if (!page1) + return 1; + *page1 = 1; + page2 = bpf_arena_alloc_pages(&arena, base + ARENA_SIZE - PAGE_SIZE * 2, + 1, NUMA_NO_NODE, 0); + if (!page2) + return 2; + *page2 = 2; + no_page = bpf_arena_alloc_pages(&arena, base + ARENA_SIZE - PAGE_SIZE, + 1, NUMA_NO_NODE, 0); + if (no_page) + return 3; + if (*page1 != 1) + return 4; + if (*page2 != 2) + return 5; + bpf_arena_free_pages(&arena, (void __arena *)page1, 1); + if (*page2 != 2) + return 6; + if (*page1 != 0) /* use-after-free should return 0 */ + return 7; + page3 = bpf_arena_alloc_pages(&arena, NULL, 1, NUMA_NO_NODE, 0); + if (!page3) + return 8; + *page3 = 3; + if (page1 != page3) + return 9; + if (*page2 != 2) + return 10; + if (*(page1 + PAGE_SIZE) != 0) + return 11; + if (*(page1 - PAGE_SIZE) != 0) + return 12; + if (*(page2 + PAGE_SIZE) != 0) + return 13; + if (*(page2 - PAGE_SIZE) != 0) + return 14; +#endif + return 0; +} + +#if defined(__BPF_FEATURE_ADDR_SPACE_CAST) +#define PAGE_CNT 100 +__u8 __arena * __arena page[PAGE_CNT]; /* occupies the first page */ +__u8 __arena *base; + +/* + * Check that arena's range_tree algorithm allocates pages sequentially + * on the first pass and then fills in all gaps on the second pass. + */ +__noinline int alloc_pages(int page_cnt, int pages_atonce, bool first_pass, + int max_idx, int step) +{ + __u8 __arena *pg; + int i, pg_idx; + + for (i = 0; i < page_cnt; i++) { + pg = bpf_arena_alloc_pages(&arena, NULL, pages_atonce, + NUMA_NO_NODE, 0); + if (!pg) + return step; + pg_idx = (unsigned long) (pg - base) / PAGE_SIZE; + if (first_pass) { + /* Pages must be allocated sequentially */ + if (pg_idx != i) + return step + 100; + } else { + /* Allocator must fill into gaps */ + if (pg_idx >= max_idx || (pg_idx & 1)) + return step + 200; + } + *pg = pg_idx; + page[pg_idx] = pg; + cond_break; + } + return 0; +} + +SEC("syscall") +__success __retval(0) +int big_alloc2(void *ctx) +{ + __u8 __arena *pg; + int i, err; + + base = bpf_arena_alloc_pages(&arena, NULL, 1, NUMA_NO_NODE, 0); + if (!base) + return 1; + bpf_arena_free_pages(&arena, (void __arena *)base, 1); + + err = alloc_pages(PAGE_CNT, 1, true, PAGE_CNT, 2); + if (err) + return err; + + /* Clear all even pages */ + for (i = 0; i < PAGE_CNT; i += 2) { + pg = page[i]; + if (*pg != i) + return 3; + bpf_arena_free_pages(&arena, (void __arena *)pg, 1); + page[i] = NULL; + cond_break; + } + + /* Allocate into freed gaps */ + err = alloc_pages(PAGE_CNT / 2, 1, false, PAGE_CNT, 4); + if (err) + return err; + + /* Free pairs of pages */ + for (i = 0; i < PAGE_CNT; i += 4) { + pg = page[i]; + if (*pg != i) + return 5; + bpf_arena_free_pages(&arena, (void __arena *)pg, 2); + page[i] = NULL; + page[i + 1] = NULL; + cond_break; + } + + /* Allocate 2 pages at a time into freed gaps */ + err = alloc_pages(PAGE_CNT / 4, 2, false, PAGE_CNT, 6); + if (err) + return err; + + /* Check pages without freeing */ + for (i = 0; i < PAGE_CNT; i += 2) { + pg = page[i]; + if (*pg != i) + return 7; + cond_break; + } + + pg = bpf_arena_alloc_pages(&arena, NULL, 1, NUMA_NO_NODE, 0); + + if (!pg) + return 8; + /* + * The first PAGE_CNT pages are occupied. The new page + * must be above. + */ + if ((pg - base) / PAGE_SIZE < PAGE_CNT) + return 9; + return 0; +} +#endif +char _license[] SEC("license") = "GPL"; |