1 /* SPDX-License-Identifier: LGPL-2.1-or-later */
2
3 #include <errno.h>
4
5 #include "alloc-util.h"
6 #include "compress.h"
7 #include "fuzz.h"
8
9 typedef struct header {
10 uint32_t alg:2; /* We have only three compression algorithms so far, but we might add more in the
11 * future. Let's make this a bit wider so our fuzzer cases remain stable in the
12 * future. */
13 uint32_t sw_len;
14 uint32_t sw_alloc;
15 uint32_t reserved[3]; /* Extra space to keep fuzz cases stable in case we need to
16 * add stuff in the future. */
17 uint8_t data[];
18 } header;
19
LLVMFuzzerTestOneInput(const uint8_t * data,size_t size)20 int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
21 _cleanup_free_ void *buf = NULL, *buf2 = NULL;
22 int r;
23
24 if (size < offsetof(header, data) + 1)
25 return 0;
26
27 const header *h = (struct header*) data;
28 const size_t data_len = size - offsetof(header, data);
29
30 int alg = h->alg;
31
32 /* We don't want to fill the logs with messages about parse errors.
33 * Disable most logging if not running standalone */
34 if (!getenv("SYSTEMD_LOG_LEVEL"))
35 log_set_max_level(LOG_CRIT);
36
37 log_info("Using compression %s, data size=%zu",
38 compression_to_string(alg),
39 data_len);
40
41 buf = malloc(MAX(size, 128u)); /* Make the buffer a bit larger for very small data */
42 if (!buf) {
43 log_oom();
44 return 0;
45 }
46
47 size_t csize;
48 r = compress_blob_explicit(alg, h->data, data_len, buf, size, &csize);
49 if (r < 0) {
50 log_error_errno(r, "Compression failed: %m");
51 return 0;
52 }
53
54 log_debug("Compressed %zu bytes to → %zu bytes", data_len, csize);
55
56 size_t sw_alloc = MAX(h->sw_alloc, 1u);
57 buf2 = malloc(sw_alloc);
58 if (!buf) {
59 log_oom();
60 return 0;
61 }
62
63 size_t sw_len = MIN(data_len - 1, h->sw_len);
64
65 r = decompress_startswith(alg, buf, csize, &buf2, h->data, sw_len, h->data[sw_len]);
66 assert_se(r > 0);
67
68 return 0;
69 }
70