fuzzer for I/O log timing files

MANIFEST

@@ -118,6 +118,7 @@ lib/iolog/iolog_path.c
 lib/iolog/iolog_util.c
 lib/iolog/regress/fuzz/fuzz_iolog_json.c
 lib/iolog/regress/fuzz/fuzz_iolog_legacy.c
+lib/iolog/regress/fuzz/fuzz_iolog_timing.c
 lib/iolog/regress/host_port/host_port_test.c  
 lib/iolog/regress/iolog_json/check_iolog_json.c
 lib/iolog/regress/iolog_json/test1.in

lib/iolog/regress/fuzz/fuzz_iolog_timing.c

@@ -0,0 +1,95 @@
+/*
+ * Copyright (c) 2021 Todd C. Miller <Todd.Miller@sudo.ws>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#include <config.h>
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <fcntl.h>
+#include <unistd.h>
+#if defined(HAVE_STDINT_H)
+# include <stdint.h>
+#elif defined(HAVE_INTTYPES_H)
+# include <inttypes.h>
+#endif
+#ifdef HAVE_STDBOOL_H
+# include <stdbool.h>
+#else
+# include "compat/stdbool.h"
+#endif /* HAVE_STDBOOL_H */
+
+#include "sudo_compat.h"
+#include "sudo_debug.h"
+#include "sudo_eventlog.h"
+#include "sudo_fatal.h"
+#include "sudo_iolog.h"
+#include "sudo_util.h"
+
+int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size)
+{
+    struct iolog_file iolog_file = { true };
+    struct timing_closure closure;
+    char logdir[] = "/tmp/timing.XXXXXX";
+    int dfd = -1, fd = -1;
+
+    if (mkdtemp(logdir) == NULL) {
+	sudo_warn_nodebug("unable to make temp dir");
+	return 0;
+    }
+    dfd = open(logdir, O_RDONLY);
+    if (dfd == -1) {
+	sudo_warn_nodebug("unable to open %s", logdir);
+	goto cleanup;
+    }
+
+    fd = openat(dfd, "timing", O_WRONLY|O_CREAT|O_EXCL, S_IRWXU);
+    if (fd == -1) {
+	sudo_warn_nodebug("unable to open %s/timing", logdir);
+	goto cleanup;
+    }
+    if (write(fd, data, size) != size) {
+	sudo_warn_nodebug("unable to write %s/timing", logdir);
+	goto cleanup;
+    }
+    close(fd);
+    fd = -1;
+
+    if (!iolog_open(&iolog_file, dfd, IOFD_TIMING, "r")) {
+	sudo_warn_nodebug("unable to iolog_open %s/timing", logdir);
+	goto cleanup;
+    }
+
+    memset(&closure, 0, sizeof(closure));
+    closure.decimal = ".";
+    for (;;) {
+	if (iolog_read_timing_record(&iolog_file, &closure) != 0)
+	    break;
+    }
+    iolog_close(&iolog_file, NULL);
+
+cleanup:
+    if (dfd != -1) {
+	if (fd != -1) {
+	    close(fd);
+	    unlinkat(dfd, "timing", 0);
+	}
+	close(dfd);
+    }
+    rmdir(logdir);
+
+    return 0;
+}