src/fuzz/fuzz-unit-file.c

   1 /* SPDX-License-Identifier: LGPL-2.1+ */
   2
   3 #include "conf-parser.h"
   4 #include "fd-util.h"
   5 #include "fileio.h"
   6 #include "fuzz.h"
   7 #include "install.h"
   8 #include "load-fragment.h"
   9 #include "string-util.h"
  10 #include "unit.h"
  11
  12 int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
  13         _cleanup_free_ char *out = NULL; /* out should be freed after g */
  14         size_t out_size;
  15         _cleanup_fclose_ FILE *f = NULL, *g = NULL;
  16         _cleanup_free_ char *p = NULL;
  17         UnitType t;
  18         _cleanup_(manager_freep) Manager *m = NULL;
  19         Unit *u;
  20         const char *name;
  21         long offset;
  22
  23         if (size == 0)
  24                 return 0;
  25
  26         f = fmemopen((char*) data, size, "re");
  27         assert_se(f);
  28
  29         if (read_line(f, LINE_MAX, &p) < 0)
  30                 return 0;
  31
  32         t = unit_type_from_string(p);
  33         if (t < 0)
  34                 return 0;
  35
  36         if (!unit_vtable[t]->load)
  37                 return 0;
  38
  39         offset = ftell(f);
  40         assert_se(offset >= 0);
  41
  42         for (;;) {
  43                 _cleanup_free_ char *l = NULL;
  44                 const char *ll;
  45
  46                 if (read_line(f, LONG_LINE_MAX, &l) <= 0)
  47                         break;
  48
  49                 ll = l + strspn(l, WHITESPACE);
  50
  51                 if (startswith(ll, "ListenNetlink=")) {
  52                         /* ListenNetlink causes a false positive in msan,
  53                          * let's skip this for now. */
  54                         log_notice("Skipping test because ListenNetlink= is present");
  55                         return 0;
  56                 }
  57         }
  58
  59         assert_se(fseek(f, offset, SEEK_SET) == 0);
  60
  61         /* We don't want to fill the logs with messages about parse errors.
  62          * Disable most logging if not running standalone */
  63         if (!getenv("SYSTEMD_LOG_LEVEL"))
  64                 log_set_max_level(LOG_CRIT);
  65
  66         assert_se(manager_new(UNIT_FILE_SYSTEM, MANAGER_TEST_RUN_MINIMAL, &m) >= 0);
  67
  68         name = strjoina("a.", unit_type_to_string(t));
  69         assert_se(unit_new_for_name(m, unit_vtable[t]->object_size, name, &u) >= 0);
  70
  71         (void) config_parse(name, name, f,
  72                             UNIT_VTABLE(u)->sections,
  73                             config_item_perf_lookup, load_fragment_gperf_lookup,
  74                             CONFIG_PARSE_ALLOW_INCLUDE, u);
  75
  76         g = open_memstream(&out, &out_size);
  77         assert_se(g);
  78
  79         unit_dump(u, g, "");
  80
  81         return 0;
  82 }