src/fuzz/fuzz-bootspec.c

   1 /* SPDX-License-Identifier: LGPL-2.1-or-later */
   2
   3 #include <string.h>
   4
   5 #include "bootspec.h"
   6 #include "env-util.h"
   7 #include "escape.h"
   8 #include "fuzz.h"
   9 #include "fd-util.h"
  10 #include "json.h"
  11
  12 static int json_dispatch_config(const char *name, JsonVariant *variant, JsonDispatchFlags flags, void *userdata) {
  13         BootConfig *config = ASSERT_PTR(userdata);
  14
  15         const char *s = json_variant_string(variant);
  16         if (!s)
  17                 return -EINVAL;
  18
  19         _cleanup_fclose_ FILE *f = NULL;
  20         assert_se(f = data_to_file((const uint8_t*) s, strlen(s)));
  21
  22         (void) boot_loader_read_conf(config, f, "memstream");
  23         return 0;
  24 }
  25
  26 static int json_dispatch_entries(const char *name, JsonVariant *variant, JsonDispatchFlags flags, void *userdata) {
  27         BootConfig *config = ASSERT_PTR(userdata);
  28         JsonVariant *entry;
  29
  30         JSON_VARIANT_ARRAY_FOREACH(entry, variant) {
  31                 if (!json_variant_is_array(entry) ||
  32                     json_variant_elements(entry) < 1)
  33                         return -EINVAL;
  34
  35                 JsonVariant *v;
  36                 const char *id = NULL, *raw = NULL;
  37                 _cleanup_free_ char *data = NULL;
  38                 ssize_t len = -ENODATA;
  39
  40                 v = json_variant_by_index(entry, 0);
  41                 if (v)
  42                         id = json_variant_string(v);
  43                 if (!id)
  44                         continue;
  45
  46                 v = json_variant_by_index(entry, 1);
  47                 if (v)
  48                         raw = json_variant_string(v);
  49                 if (raw)
  50                         len = cunescape(raw, UNESCAPE_RELAX | UNESCAPE_ACCEPT_NUL, &data);
  51                 if (len >= 0) {
  52                         _cleanup_fclose_ FILE *f = NULL;
  53                         assert_se(f = data_to_file((const uint8_t*) data, len));
  54
  55                         assert_se(boot_config_load_type1(config, f, "/", "/entries", id) != -ENOMEM);
  56                 }
  57         }
  58
  59         return 0;
  60 }
  61
  62 static int json_dispatch_loader(const char *name, JsonVariant *variant, JsonDispatchFlags flags, void *userdata) {
  63         BootConfig *config = ASSERT_PTR(userdata);
  64         _cleanup_strv_free_ char **entries = NULL;
  65         int r;
  66
  67         r = json_dispatch_strv(name, variant, flags, &entries);
  68         if (r < 0)
  69                 return r;
  70
  71         (void) boot_config_augment_from_loader(config, entries, false);
  72         return 0;
  73 }
  74
  75 static const JsonDispatch data_dispatch[] = {
  76         { "config",  JSON_VARIANT_STRING, json_dispatch_config,  0, 0 },
  77         { "entries", JSON_VARIANT_ARRAY,  json_dispatch_entries, 0, 0 },
  78         { "loader",  JSON_VARIANT_ARRAY,  json_dispatch_loader,  0, 0 },
  79         {}
  80 };
  81
  82 int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
  83         _cleanup_free_ const char *datadup = NULL;
  84         _cleanup_(boot_config_free) BootConfig config = BOOT_CONFIG_NULL;
  85         int r;
  86
  87         if (outside_size_range(size, 0, 65536))
  88                 return 0;
  89
  90         /* Disable most logging if not running standalone */
  91         if (!getenv("SYSTEMD_LOG_LEVEL"))
  92                 log_set_max_level(LOG_CRIT);
  93
  94         assert_se(datadup = memdup_suffix0(data, size));
  95
  96         _cleanup_(json_variant_unrefp) JsonVariant *v = NULL;
  97         r = json_parse(datadup, 0, &v, NULL, NULL);
  98         if (r < 0)
  99                 return 0;
 100
 101         r = json_dispatch(v, data_dispatch, NULL, 0, &config);
 102         if (r < 0)
 103                 return 0;
 104
 105         assert_se(boot_config_finalize(&config) >= 0);
 106
 107         (void) boot_config_select_special_entries(&config, /* skip_efivars= */ false);
 108
 109         _cleanup_close_ int orig_stdout_fd = -EBADF;
 110         if (getenv_bool("SYSTEMD_FUZZ_OUTPUT") <= 0) {
 111                 orig_stdout_fd = fcntl(fileno(stdout), F_DUPFD_CLOEXEC, 3);
 112                 if (orig_stdout_fd < 0)
 113                         log_warning_errno(orig_stdout_fd, "Failed to duplicate fd 1: %m");
 114                 else
 115                         assert_se(freopen("/dev/null", "w", stdout));
 116         }
 117
 118         (void) show_boot_entries(&config, JSON_FORMAT_OFF);
 119         (void) show_boot_entries(&config, JSON_FORMAT_PRETTY);
 120
 121         if (orig_stdout_fd >= 0)
 122                 assert_se(freopen(FORMAT_PROC_FD_PATH(orig_stdout_fd), "w", stdout));
 123
 124         return 0;
 125 }