tools/fuzz: introduce libelf target

Source code and Makefile to fuzz libelf in Google's oss-fuzz
infrastructure.

Introduce FUZZ_NO_LIBXC in libelf-private.h. That macro will be set when
compiling libelf fuzzer target because libxc is not required in libelf
fuzzing.

Signed-off-by: Wei Liu <wei.liu2@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>

diff --git a/tools/fuzz/libelf/Makefile b/tools/fuzz/libelf/Makefile
new file mode 100644 (file)
index 0000000..0e9d40a
--- /dev/null
+++ b/tools/fuzz/libelf/Makefile
@@ -0,0 +1,31 @@
+XEN_ROOT = $(CURDIR)/../../..
+include $(XEN_ROOT)/tools/Rules.mk
+
+# libelf fuzz target
+vpath %.c ../../../xen/common/libelf
+CFLAGS += -I../../../xen/common/libelf
+ELF_SRCS-y += libelf-tools.c libelf-loader.c libelf-dominfo.c
+ELF_LIB_OBJS := $(patsubst %.c,%.o,$(ELF_SRCS-y))
+
+$(patsubst %.c,%.o,$(ELF_SRCS-y)): CFLAGS += -Wno-pointer-sign
+
+$(ELF_LIB_OBJS): CFLAGS += -DFUZZ_NO_LIBXC $(CFLAGS_xeninclude)
+
+libelf-fuzzer.o: CFLAGS += $(CFLAGS_xeninclude)
+
+libelf.a: $(ELF_LIB_OBJS)
+       $(AR) rc $@ $^
+
+.PHONY: libelf-fuzzer-all
+libelf-fuzzer-all: libelf.a libelf-fuzzer.o
+
+# Common targets
+.PHONY: all
+all: libelf-fuzzer-all
+
+.PHONY: distclean
+distclean: clean
+
+.PHONY: clean
+clean:
+       rm -f *.o *.a

diff --git a/tools/fuzz/libelf/libelf-fuzzer.c b/tools/fuzz/libelf/libelf-fuzzer.c
new file mode 100644 (file)
index 0000000..71561d3
--- /dev/null
+++ b/tools/fuzz/libelf/libelf-fuzzer.c
@@ -0,0 +1,32 @@
+#include <inttypes.h>
+#include <stddef.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include <xen/libelf/libelf.h>
+
+int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size)
+{
+    struct elf_binary elf_buf, *elf;
+    struct elf_dom_parms parms;
+
+    elf = &elf_buf;
+
+    memset(elf, 0, sizeof(*elf));
+    elf_init(elf, (const char *)data, size);
+    elf_parse_binary(elf);
+    elf_xen_parse(elf, &parms);
+
+    return 0;
+}
+
+
+/*
+ * Local variables:
+ * mode: C
+ * c-file-style: "BSD"
+ * c-basic-offset: 4
+ * tab-width: 4
+ * indent-tabs-mode: nil
+ * End:
+ */

diff --git a/xen/common/libelf/libelf-private.h b/xen/common/libelf/libelf-private.h
index 388c3da34ddead76599a48e2f403e351f50f448c..47db679966c6d0019a883123e7323fd28a96e1a6 100644 (file)
--- a/xen/common/libelf/libelf-private.h
+++ b/xen/common/libelf/libelf-private.h
@@ -72,8 +72,10 @@
 #include <xen/elfnote.h>
 #include <xen/libelf/libelf.h>
 
+#ifndef FUZZ_NO_LIBXC
 #include "xenctrl.h"
 #include "xc_private.h"
+#endif
 
 #define elf_msg(elf, fmt, args ... )                    \
     elf_call_log_callback(elf, 0, fmt , ## args );