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authorvan Hauser <vh@thc.org>2020-07-30 17:09:22 +0200
committervan Hauser <vh@thc.org>2020-07-30 17:09:22 +0200
commitea9ba53cdbc6d175f3f055c9a308668ebaacda1e (patch)
treee902b997bf3967a43f3a307e40aebde9675ac26d
parent1ba48a5ba06106148b1b0e8d56472738fb2ce44c (diff)
downloadafl++-ea9ba53cdbc6d175f3f055c9a308668ebaacda1e.tar.gz
fix oob reads, code-format
-rw-r--r--examples/aflpp_driver/aflpp_driver.c168
-rw-r--r--examples/aflpp_driver/aflpp_driver_test.c16
-rw-r--r--src/afl-fuzz-queue.c55
-rw-r--r--src/afl-fuzz-redqueen.c3
-rw-r--r--test/test-floatingpoint.c8
5 files changed, 146 insertions, 104 deletions
diff --git a/examples/aflpp_driver/aflpp_driver.c b/examples/aflpp_driver/aflpp_driver.c
index eca3dcd1..86c7a69f 100644
--- a/examples/aflpp_driver/aflpp_driver.c
+++ b/examples/aflpp_driver/aflpp_driver.c
@@ -14,12 +14,15 @@ cat << EOF > test_fuzzer.cc
#include <stddef.h>
#include <stdint.h>
extern "C" int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
+
if (size > 0 && data[0] == 'H')
if (size > 1 && data[1] == 'I')
if (size > 2 && data[2] == '!')
__builtin_trap();
return 0;
+
}
+
EOF
# Build your target with -fsanitize-coverage=trace-pc-guard using fresh clang.
clang -g -fsanitize-coverage=trace-pc-guard test_fuzzer.cc -c
@@ -57,46 +60,46 @@ If 1, close stdout at startup. If 2 close stderr; if 3 close both.
#include "config.h"
#ifdef _DEBUG
-#include "hash.h"
+ #include "hash.h"
#endif
// Platform detection. Copied from FuzzerInternal.h
#ifdef __linux__
-#define LIBFUZZER_LINUX 1
-#define LIBFUZZER_APPLE 0
-#define LIBFUZZER_NETBSD 0
-#define LIBFUZZER_FREEBSD 0
-#define LIBFUZZER_OPENBSD 0
+ #define LIBFUZZER_LINUX 1
+ #define LIBFUZZER_APPLE 0
+ #define LIBFUZZER_NETBSD 0
+ #define LIBFUZZER_FREEBSD 0
+ #define LIBFUZZER_OPENBSD 0
#elif __APPLE__
-#define LIBFUZZER_LINUX 0
-#define LIBFUZZER_APPLE 1
-#define LIBFUZZER_NETBSD 0
-#define LIBFUZZER_FREEBSD 0
-#define LIBFUZZER_OPENBSD 0
+ #define LIBFUZZER_LINUX 0
+ #define LIBFUZZER_APPLE 1
+ #define LIBFUZZER_NETBSD 0
+ #define LIBFUZZER_FREEBSD 0
+ #define LIBFUZZER_OPENBSD 0
#elif __NetBSD__
-#define LIBFUZZER_LINUX 0
-#define LIBFUZZER_APPLE 0
-#define LIBFUZZER_NETBSD 1
-#define LIBFUZZER_FREEBSD 0
-#define LIBFUZZER_OPENBSD 0
+ #define LIBFUZZER_LINUX 0
+ #define LIBFUZZER_APPLE 0
+ #define LIBFUZZER_NETBSD 1
+ #define LIBFUZZER_FREEBSD 0
+ #define LIBFUZZER_OPENBSD 0
#elif __FreeBSD__
-#define LIBFUZZER_LINUX 0
-#define LIBFUZZER_APPLE 0
-#define LIBFUZZER_NETBSD 0
-#define LIBFUZZER_FREEBSD 1
-#define LIBFUZZER_OPENBSD 0
+ #define LIBFUZZER_LINUX 0
+ #define LIBFUZZER_APPLE 0
+ #define LIBFUZZER_NETBSD 0
+ #define LIBFUZZER_FREEBSD 1
+ #define LIBFUZZER_OPENBSD 0
#elif __OpenBSD__
-#define LIBFUZZER_LINUX 0
-#define LIBFUZZER_APPLE 0
-#define LIBFUZZER_NETBSD 0
-#define LIBFUZZER_FREEBSD 0
-#define LIBFUZZER_OPENBSD 1
+ #define LIBFUZZER_LINUX 0
+ #define LIBFUZZER_APPLE 0
+ #define LIBFUZZER_NETBSD 0
+ #define LIBFUZZER_FREEBSD 0
+ #define LIBFUZZER_OPENBSD 1
#else
-#error "Support for your platform has not been implemented"
+ #error "Support for your platform has not been implemented"
#endif
-int __afl_sharedmem_fuzzing = 1;
-extern unsigned int *__afl_fuzz_len;
+int __afl_sharedmem_fuzzing = 1;
+extern unsigned int * __afl_fuzz_len;
extern unsigned char *__afl_fuzz_ptr;
// libFuzzer interface is thin, so we don't include any libFuzzer headers.
@@ -105,11 +108,11 @@ __attribute__((weak)) int LLVMFuzzerInitialize(int *argc, char ***argv);
// Notify AFL about persistent mode.
static volatile char AFL_PERSISTENT[] = "##SIG_AFL_PERSISTENT##";
-int __afl_persistent_loop(unsigned int);
+int __afl_persistent_loop(unsigned int);
// Notify AFL about deferred forkserver.
static volatile char AFL_DEFER_FORKSVR[] = "##SIG_AFL_DEFER_FORKSRV##";
-void __afl_manual_init();
+void __afl_manual_init();
// Use this optionally defined function to output sanitizer messages even if
// user asks to close stderr.
@@ -122,98 +125,121 @@ static FILE *output_file;
// Experimental feature to use afl_driver without AFL's deferred mode.
// Needs to run before __afl_auto_init.
__attribute__((constructor(0))) static void __decide_deferred_forkserver(void) {
+
if (getenv("AFL_DRIVER_DONT_DEFER")) {
+
if (unsetenv("__AFL_DEFER_FORKSRV")) {
+
perror("Failed to unset __AFL_DEFER_FORKSRV");
abort();
+
}
+
}
+
}
// If the user asks us to duplicate stderr, then do it.
static void maybe_duplicate_stderr() {
+
char *stderr_duplicate_filename =
getenv("AFL_DRIVER_STDERR_DUPLICATE_FILENAME");
- if (!stderr_duplicate_filename)
- return;
+ if (!stderr_duplicate_filename) return;
FILE *stderr_duplicate_stream =
freopen(stderr_duplicate_filename, "a+", stderr);
if (!stderr_duplicate_stream) {
+
fprintf(
stderr,
"Failed to duplicate stderr to AFL_DRIVER_STDERR_DUPLICATE_FILENAME");
abort();
+
}
+
output_file = stderr_duplicate_stream;
+
}
// Most of these I/O functions were inspired by/copied from libFuzzer's code.
static void discard_output(int fd) {
+
FILE *temp = fopen("/dev/null", "w");
- if (!temp)
- abort();
+ if (!temp) abort();
dup2(fileno(temp), fd);
fclose(temp);
+
}
-static void close_stdout() { discard_output(STDOUT_FILENO); }
+static void close_stdout() {
+
+ discard_output(STDOUT_FILENO);
+
+}
// Prevent the targeted code from writing to "stderr" but allow sanitizers and
// this driver to do so.
static void dup_and_close_stderr() {
+
int output_fileno = fileno(output_file);
int output_fd = dup(output_fileno);
- if (output_fd <= 0)
- abort();
+ if (output_fd <= 0) abort();
FILE *new_output_file = fdopen(output_fd, "w");
- if (!new_output_file)
- abort();
- if (!__sanitizer_set_report_fd)
- return;
- __sanitizer_set_report_fd((void*)output_fd);
+ if (!new_output_file) abort();
+ if (!__sanitizer_set_report_fd) return;
+ __sanitizer_set_report_fd((void *)output_fd);
discard_output(output_fileno);
+
}
// Close stdout and/or stderr if user asks for it.
static void maybe_close_fd_mask() {
+
char *fd_mask_str = getenv("AFL_DRIVER_CLOSE_FD_MASK");
- if (!fd_mask_str)
- return;
+ if (!fd_mask_str) return;
int fd_mask = atoi(fd_mask_str);
- if (fd_mask & 2)
- dup_and_close_stderr();
- if (fd_mask & 1)
- close_stdout();
+ if (fd_mask & 2) dup_and_close_stderr();
+ if (fd_mask & 1) close_stdout();
+
}
// Define LLVMFuzzerMutate to avoid link failures for targets that use it
// with libFuzzer's LLVMFuzzerCustomMutator.
size_t LLVMFuzzerMutate(uint8_t *Data, size_t Size, size_t MaxSize) {
- //assert(false && "LLVMFuzzerMutate should not be called from afl_driver");
+
+ // assert(false && "LLVMFuzzerMutate should not be called from afl_driver");
return 0;
+
}
// Execute any files provided as parameters.
static int ExecuteFilesOnyByOne(int argc, char **argv) {
+
unsigned char *buf = malloc(MAX_FILE);
for (int i = 1; i < argc; i++) {
+
int fd = open(argv[i], O_RDONLY);
if (fd == -1) continue;
ssize_t length = read(fd, buf, MAX_FILE);
if (length > 0) {
+
printf("Reading %zu bytes from %s\n", length, argv[i]);
LLVMFuzzerTestOneInput(buf, length);
printf("Execution successful.\n");
+
}
+
}
+
free(buf);
return 0;
+
}
int main(int argc, char **argv) {
+
printf(
"======================= INFO =========================\n"
"This binary is built for AFL-fuzz.\n"
@@ -226,36 +252,39 @@ int main(int argc, char **argv) {
"afl-fuzz will run N iterations before "
"re-spawning the process (default: 1000)\n"
"======================================================\n",
- argv[0], argv[0], argv[0]);
+ argv[0], argv[0], argv[0]);
output_file = stderr;
maybe_duplicate_stderr();
maybe_close_fd_mask();
- if (LLVMFuzzerInitialize)
- LLVMFuzzerInitialize(&argc, &argv);
+ if (LLVMFuzzerInitialize) LLVMFuzzerInitialize(&argc, &argv);
// Do any other expensive one-time initialization here.
uint8_t dummy_input[64] = {0};
- memcpy(dummy_input, (void*)AFL_PERSISTENT, sizeof(AFL_PERSISTENT));
- memcpy(dummy_input + 32, (void*)AFL_DEFER_FORKSVR, sizeof(AFL_DEFER_FORKSVR));
+ memcpy(dummy_input, (void *)AFL_PERSISTENT, sizeof(AFL_PERSISTENT));
+ memcpy(dummy_input + 32, (void *)AFL_DEFER_FORKSVR,
+ sizeof(AFL_DEFER_FORKSVR));
int N = INT_MAX;
if (argc == 2 && argv[1][0] == '-')
- N = atoi(argv[1] + 1);
- else if(argc == 2 && (N = atoi(argv[1])) > 0)
- printf("WARNING: using the deprecated call style `%s %d`\n", argv[0], N);
+ N = atoi(argv[1] + 1);
+ else if (argc == 2 && (N = atoi(argv[1])) > 0)
+ printf("WARNING: using the deprecated call style `%s %d`\n", argv[0], N);
else if (argc > 1) {
-// if (!getenv("AFL_DRIVER_DONT_DEFER")) {
- __afl_sharedmem_fuzzing = 0;
- __afl_manual_init();
-// }
+
+ // if (!getenv("AFL_DRIVER_DONT_DEFER")) {
+
+ __afl_sharedmem_fuzzing = 0;
+ __afl_manual_init();
+ // }
return ExecuteFilesOnyByOne(argc, argv);
exit(0);
+
}
assert(N > 0);
-// if (!getenv("AFL_DRIVER_DONT_DEFER"))
+ // if (!getenv("AFL_DRIVER_DONT_DEFER"))
__afl_manual_init();
// Call LLVMFuzzerTestOneInput here so that coverage caused by initialization
@@ -264,17 +293,26 @@ int main(int argc, char **argv) {
int num_runs = 0;
while (__afl_persistent_loop(N)) {
+
#ifdef _DEBUG
- fprintf(stderr, "CLIENT crc: %016llx len: %u\n", hash64(__afl_fuzz_ptr, *__afl_fuzz_len, 0xa5b35705), *__afl_fuzz_len);
+ fprintf(stderr, "CLIENT crc: %016llx len: %u\n",
+ hash64(__afl_fuzz_ptr, *__afl_fuzz_len, 0xa5b35705),
+ *__afl_fuzz_len);
fprintf(stderr, "RECV:");
for (int i = 0; i < *__afl_fuzz_len; i++)
fprintf(stderr, "%02x", __afl_fuzz_ptr[i]);
- fprintf(stderr,"\n");
+ fprintf(stderr, "\n");
#endif
if (*__afl_fuzz_len) {
+
num_runs++;
LLVMFuzzerTestOneInput(__afl_fuzz_ptr, *__afl_fuzz_len);
+
}
+
}
+
printf("%s: successfully executed %d input(s)\n", argv[0], num_runs);
+
}
+
diff --git a/examples/aflpp_driver/aflpp_driver_test.c b/examples/aflpp_driver/aflpp_driver_test.c
index 83278f5c..e4567bbf 100644
--- a/examples/aflpp_driver/aflpp_driver_test.c
+++ b/examples/aflpp_driver/aflpp_driver_test.c
@@ -6,18 +6,20 @@
int LLVMFuzzerTestOneInput(const uint8_t *Data, size_t Size) {
- fprintf(stderr, "FUNC crc: %016llx len: %lu\n", hash64((u8*)Data, (unsigned int) Size, (unsigned long long int) 0xa5b35705), Size);
-
- if (Size < 5)
- return 0;
+ fprintf(stderr, "FUNC crc: %016llx len: %lu\n",
+ hash64((u8 *)Data, (unsigned int)Size,
+ (unsigned long long int)0xa5b35705),
+ Size);
+
+ if (Size < 5) return 0;
if (Data[0] == 'F')
if (Data[1] == 'A')
if (Data[2] == '$')
if (Data[3] == '$')
- if (Data[4] == '$')
- abort();
-
+ if (Data[4] == '$') abort();
+
return 0;
}
+
diff --git a/src/afl-fuzz-queue.c b/src/afl-fuzz-queue.c
index 38e95ac8..71874283 100644
--- a/src/afl-fuzz-queue.c
+++ b/src/afl-fuzz-queue.c
@@ -139,7 +139,8 @@ static u8 check_if_text(struct queue_entry *q) {
// non-overlong 2-byte
if (((0xC2 <= buf[offset + 0] && buf[offset + 0] <= 0xDF) &&
- (0x80 <= buf[offset + 1] && buf[offset + 1] <= 0xBF))) {
+ (0x80 <= buf[offset + 1] && buf[offset + 1] <= 0xBF)) &&
+ len - offset > 1) {
offset += 2;
utf8++;
@@ -149,18 +150,19 @@ static u8 check_if_text(struct queue_entry *q) {
}
// excluding overlongs
- if ((buf[offset + 0] == 0xE0 &&
- (0xA0 <= buf[offset + 1] && buf[offset + 1] <= 0xBF) &&
- (0x80 <= buf[offset + 2] &&
- buf[offset + 2] <= 0xBF)) || // straight 3-byte
- (((0xE1 <= buf[offset + 0] && buf[offset + 0] <= 0xEC) ||
- buf[offset + 0] == 0xEE || buf[offset + 0] == 0xEF) &&
- (0x80 <= buf[offset + 1] && buf[offset + 1] <= 0xBF) &&
- (0x80 <= buf[offset + 2] &&
- buf[offset + 2] <= 0xBF)) || // excluding surrogates
- (buf[offset + 0] == 0xED &&
- (0x80 <= buf[offset + 1] && buf[offset + 1] <= 0x9F) &&
- (0x80 <= buf[offset + 2] && buf[offset + 2] <= 0xBF))) {
+ if ((len - offset > 2) &&
+ ((buf[offset + 0] == 0xE0 &&
+ (0xA0 <= buf[offset + 1] && buf[offset + 1] <= 0xBF) &&
+ (0x80 <= buf[offset + 2] &&
+ buf[offset + 2] <= 0xBF)) || // straight 3-byte
+ (((0xE1 <= buf[offset + 0] && buf[offset + 0] <= 0xEC) ||
+ buf[offset + 0] == 0xEE || buf[offset + 0] == 0xEF) &&
+ (0x80 <= buf[offset + 1] && buf[offset + 1] <= 0xBF) &&
+ (0x80 <= buf[offset + 2] &&
+ buf[offset + 2] <= 0xBF)) || // excluding surrogates
+ (buf[offset + 0] == 0xED &&
+ (0x80 <= buf[offset + 1] && buf[offset + 1] <= 0x9F) &&
+ (0x80 <= buf[offset + 2] && buf[offset + 2] <= 0xBF)))) {
offset += 3;
utf8++;
@@ -170,19 +172,20 @@ static u8 check_if_text(struct queue_entry *q) {
}
// planes 1-3
- if ((buf[offset + 0] == 0xF0 &&
- (0x90 <= buf[offset + 1] && buf[offset + 1] <= 0xBF) &&
- (0x80 <= buf[offset + 2] && buf[offset + 2] <= 0xBF) &&
- (0x80 <= buf[offset + 3] &&
- buf[offset + 3] <= 0xBF)) || // planes 4-15
- ((0xF1 <= buf[offset + 0] && buf[offset + 0] <= 0xF3) &&
- (0x80 <= buf[offset + 1] && buf[offset + 1] <= 0xBF) &&
- (0x80 <= buf[offset + 2] && buf[offset + 2] <= 0xBF) &&
- (0x80 <= buf[offset + 3] && buf[offset + 3] <= 0xBF)) || // plane 16
- (buf[offset + 0] == 0xF4 &&
- (0x80 <= buf[offset + 1] && buf[offset + 1] <= 0x8F) &&
- (0x80 <= buf[offset + 2] && buf[offset + 2] <= 0xBF) &&
- (0x80 <= buf[offset + 3] && buf[offset + 3] <= 0xBF))) {
+ if ((len - offset > 3) &&
+ ((buf[offset + 0] == 0xF0 &&
+ (0x90 <= buf[offset + 1] && buf[offset + 1] <= 0xBF) &&
+ (0x80 <= buf[offset + 2] && buf[offset + 2] <= 0xBF) &&
+ (0x80 <= buf[offset + 3] &&
+ buf[offset + 3] <= 0xBF)) || // planes 4-15
+ ((0xF1 <= buf[offset + 0] && buf[offset + 0] <= 0xF3) &&
+ (0x80 <= buf[offset + 1] && buf[offset + 1] <= 0xBF) &&
+ (0x80 <= buf[offset + 2] && buf[offset + 2] <= 0xBF) &&
+ (0x80 <= buf[offset + 3] && buf[offset + 3] <= 0xBF)) || // plane 16
+ (buf[offset + 0] == 0xF4 &&
+ (0x80 <= buf[offset + 1] && buf[offset + 1] <= 0x8F) &&
+ (0x80 <= buf[offset + 2] && buf[offset + 2] <= 0xBF) &&
+ (0x80 <= buf[offset + 3] && buf[offset + 3] <= 0xBF)))) {
offset += 4;
utf8++;
diff --git a/src/afl-fuzz-redqueen.c b/src/afl-fuzz-redqueen.c
index 57e60c3d..a2e8f992 100644
--- a/src/afl-fuzz-redqueen.c
+++ b/src/afl-fuzz-redqueen.c
@@ -269,8 +269,7 @@ static long long strntoll(const char *str, size_t sz, char **end, int base) {
long long ret;
const char *beg = str;
- for (; beg && sz && *beg == ' '; beg++, sz--)
- ;
+ for (; beg && sz && *beg == ' '; beg++, sz--) {};
if (!sz || sz >= sizeof(buf)) {
diff --git a/test/test-floatingpoint.c b/test/test-floatingpoint.c
index d1709b90..3a699595 100644
--- a/test/test-floatingpoint.c
+++ b/test/test-floatingpoint.c
@@ -17,10 +17,10 @@ int main(void) {
int len = __AFL_FUZZ_TESTCASE_LEN;
if (len != sizeof(float)) return 1;
- /* 15 + 1/2 = 15.5 */
- /* 15 + 1/2 + 1/8 = 15.625 */
- /* 15 + 1/2 + 1/8 + 1/32 = 15.65625 */
- /* 15 + 1/2 + 1/8 + 1/32 + 1/128 = 15.6640625 */
+ /* 15 + 1/2 = 15.5 */
+ /* 15 + 1/2 + 1/8 = 15.625 */
+ /* 15 + 1/2 + 1/8 + 1/32 = 15.65625 */
+ /* 15 + 1/2 + 1/8 + 1/32 + 1/128 = 15.6640625 */
if ((-*magic == 15.0 + 0.5 + 0.125 + 0.03125 + 0.0078125)) abort();
}