Add fuzzer for metaflac command-line tool

oss-fuzz/Makefile.am

@@ -35,7 +35,7 @@ EXTRA_DIST = \
 noinst_PROGRAMS =
 
 if USE_OSSFUZZERS
-noinst_PROGRAMS += fuzzer_encoder fuzzer_encoder_v2 fuzzer_decoder fuzzer_seek fuzzer_metadata fuzzer_reencoder fuzzer_tool_flac
+noinst_PROGRAMS += fuzzer_encoder fuzzer_encoder_v2 fuzzer_decoder fuzzer_seek fuzzer_metadata fuzzer_reencoder fuzzer_tool_flac fuzzer_tool_metaflac
 endif
 
 fuzzer_encoder_SOURCES = encoder.cc
@@ -54,6 +54,16 @@ fuzzer_tool_flac_LDADD =  \
         $(top_builddir)/src/libFLAC/libFLAC.la \
         @LTLIBICONV@ \
         -lm
+fuzzer_tool_metaflac_SOURCES = ${metaflac_SOURCES} empty.cc tool_metaflac.c # empty.cc is to force use of C++ linker, which is mandated by oss-fuzz
+fuzzer_tool_metaflac_LDADD =  \
+        $(top_builddir)/src/share/utf8/libutf8.la \
+        $(top_builddir)/src/share/grabbag/libgrabbag.la \
+        $(top_builddir)/src/share/getopt/libgetopt.la \
+        $(top_builddir)/src/share/replaygain_analysis/libreplaygain_analysis.la \
+        $(top_builddir)/src/share/replaygain_synthesis/libreplaygain_synthesis.la \
+        $(top_builddir)/src/libFLAC/libFLAC.la \
+        @LTLIBICONV@ \
+        -lm
 
 flac_libs = \
 	$(top_builddir)/src/libFLAC/libFLAC-static.la \
@@ -76,3 +86,19 @@ flac_SOURCES = \
         ${top_builddir}/src/flac/local_string_utils.h \
         ${top_builddir}/src/flac/utils.h \
         ${top_builddir}/src/flac/vorbiscomment.h
+
+metaflac_SOURCES = \
+        ${top_builddir}/src/metaflac/operations.c \
+        ${top_builddir}/src/metaflac/operations_shorthand_cuesheet.c \
+        ${top_builddir}/src/metaflac/operations_shorthand_picture.c \
+        ${top_builddir}/src/metaflac/operations_shorthand_seektable.c \
+        ${top_builddir}/src/metaflac/operations_shorthand_streaminfo.c \
+        ${top_builddir}/src/metaflac/operations_shorthand_vorbiscomment.c \
+        ${top_builddir}/src/metaflac/options.c \
+        ${top_builddir}/src/metaflac/usage.c \
+        ${top_builddir}/src/metaflac/utils.c \
+        ${top_builddir}/src/metaflac/operations.h \
+        ${top_builddir}/src/metaflac/operations_shorthand.h \
+        ${top_builddir}/src/metaflac/options.h \
+        ${top_builddir}/src/metaflac/usage.h \
+        ${top_builddir}/src/metaflac/utils.h

oss-fuzz/tool_metaflac.c

@@ -0,0 +1,102 @@
+/* fuzzer_tool_flac
+ * Copyright (C) 2023  Xiph.Org Foundation
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * - Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *
+ * - Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ *
+ * - Neither the name of the Xiph.org Foundation nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR
+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+ * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+ * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+ * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h> /* for memcpy */
+#define FUZZ_TOOL_METAFLAC
+#define fprintf(...)
+#define printf(...)
+#include "../src/metaflac/main.c"
+#include "common.h"
+
+int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size);
+
+int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size)
+{
+	size_t size_left = size;
+	size_t arglen;
+	char * argv[64];
+	char exename[] = "metaflac";
+	char filename[] = "/tmp/fuzzXXXXXX";
+	int numarg = 0, maxarg;
+	int file_to_fuzz;
+	int tmp_stderr, tmp_stdout;
+	fpos_t pos_stderr, pos_stdout;
+
+	share__opterr = 0;
+	share__optind = 0;
+
+
+	if(size < 2)
+		return 0;
+
+	maxarg = data[0] & 16;
+	size_left--;
+
+	argv[0] = exename;
+	numarg++;
+
+	/* Check whether input is zero delimited */
+	while((arglen = strnlen((char *)data+(size-size_left),size_left)) < size_left && numarg < maxarg) {
+		argv[numarg++] = (char *)data+(size-size_left);
+		size_left -= arglen + 1;
+	}
+
+	file_to_fuzz = mkstemp(filename);
+
+	if (file_to_fuzz < 0)
+		abort();
+	write(file_to_fuzz,data+(size-size_left),size_left);
+	close(file_to_fuzz);
+
+	argv[numarg++] = filename;
+
+	/* redirect stderr and stdout */
+	fflush(stdout);
+	fgetpos(stdout,&pos_stdout);
+	tmp_stdout = dup(fileno(stdout));
+	freopen("/dev/null","w",stdout);
+
+	main_to_fuzz(numarg,argv);
+
+	/* restore stderr and stdout */
+	fflush(stdout);
+	dup2(tmp_stdout, fileno(stdout));
+	close(tmp_stdout);
+	clearerr(stdout);
+	fsetpos(stdout,&pos_stdout);
+
+	unlink(filename);
+
+	return 0;
+}
+

src/metaflac/main.c

@@ -28,7 +28,11 @@
 #include <string.h>
 #include "share/compat.h"
 
+#ifndef FUZZ_TOOL_METAFLAC
 int main(int argc, char *argv[])
+#else
+static int main_to_fuzz(int argc, char *argv[])
+#endif
 {
 	CommandLineOptions options;
 	int ret = 0;

src/metaflac/operations_shorthand_cuesheet.c

@@ -122,9 +122,11 @@ FLAC__bool import_cs_from(const char *filename, FLAC__StreamMetadata **cuesheet,
 		flac_fprintf(stderr, "%s: ERROR: empty import file name\n", filename);
 		return false;
 	}
+#ifndef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION
 	if(0 == strcmp(cs_filename, "-"))
 		f = stdin;
 	else
+#endif
 		f = flac_fopen(cs_filename, "r");
 
 	if(0 == f) {

src/metaflac/operations_shorthand_vorbiscomment.c

@@ -347,9 +347,11 @@ FLAC__bool import_vc_from(const char *filename, FLAC__StreamMetadata *block, con
 		flac_fprintf(stderr, "%s: ERROR: empty import file name\n", filename);
 		return false;
 	}
+#ifndef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION
 	if(0 == strcmp(vc_filename->value, "-"))
 		f = stdin;
 	else
+#endif
 		f = flac_fopen(vc_filename->value, "r");
 
 	if(0 == f) {

src/metaflac/usage.c

@@ -21,6 +21,7 @@
 #  include <config.h>
 #endif
 
+#include "utils.h"
 #include "usage.h"
 #include "FLAC/format.h"
 #include <stdarg.h>

src/metaflac/utils.h

@@ -23,6 +23,11 @@
 #include "FLAC/metadata.h"
 #include <stdio.h> /* for FILE */
 
+#ifdef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION
+#undef stderr
+#define stderr stdout
+#endif
+
 void die(const char *message);
 #ifdef FLAC__VALGRIND_TESTING
 size_t local_fwrite(const void *ptr, size_t size, size_t nmemb, FILE *stream);