diff --git a/curl_fuzzer.cc b/curl_fuzzer.cc index b66130f5..bf1cee73 100644 --- a/curl_fuzzer.cc +++ b/curl_fuzzer.cc @@ -27,6 +27,8 @@ #include #include "curl_fuzzer.h" +#include "nallocinc.c" + /** * Fuzzing entry point. This function is passed a buffer containing a test * case. This test case should drive the CURL API into making a request. @@ -49,6 +51,7 @@ extern "C" int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) goto EXIT_LABEL; } + nalloc_init(NULL); /* Try to initialize the fuzz data */ FTRY(fuzz_initialize_fuzz_data(&fuzz, data, size)); @@ -93,8 +96,10 @@ extern "C" int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) curl_easy_setopt(fuzz.easy, CURLOPT_HTTPPOST, fuzz.httppost); } + nalloc_start(data, size); /* Run the transfer. */ fuzz_handle_transfer(&fuzz); + nalloc_end(); EXIT_LABEL: diff --git a/nallocinc.c b/nallocinc.c new file mode 100644 index 00000000..3ff8335f --- /dev/null +++ b/nallocinc.c @@ -0,0 +1,396 @@ +/* + MIT License + + Copyright (c) 2025 Catena cyber + + Permission is hereby granted, free of charge, to any person obtaining a copy + of this software and associated documentation files (the "Software"), to deal + in the Software without restriction, including without limitation the rights + to use, copy, modify, merge, publish, distribute, sublicense, and/or sell + copies of the Software, and to permit persons to whom the Software is + furnished to do so, subject to the following conditions: + + The above copyright notice and this permission notice shall be included in all + copies or substantial portions of the Software. + + THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE + AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER + LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, + OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + SOFTWARE. +*/ + +#if defined(__clang__) && defined(__has_feature) +#if __has_feature(address_sanitizer) +#define NALLOC_ASAN 1 +#endif +#endif + +#include +#include +#include +#include +#include +#ifdef NALLOC_LIBBACKTRACE +#include "libbacktrace/backtrace.h" +#endif +#include + +#ifdef __cplusplus +extern "C" { +#endif + +static const uint32_t nalloc_crc32_table[] = { + 0x00000000, 0x04c11db7, 0x09823b6e, 0x0d4326d9, 0x130476dc, 0x17c56b6b, + 0x1a864db2, 0x1e475005, 0x2608edb8, 0x22c9f00f, 0x2f8ad6d6, 0x2b4bcb61, + 0x350c9b64, 0x31cd86d3, 0x3c8ea00a, 0x384fbdbd, 0x4c11db70, 0x48d0c6c7, + 0x4593e01e, 0x4152fda9, 0x5f15adac, 0x5bd4b01b, 0x569796c2, 0x52568b75, + 0x6a1936c8, 0x6ed82b7f, 0x639b0da6, 0x675a1011, 0x791d4014, 0x7ddc5da3, + 0x709f7b7a, 0x745e66cd, 0x9823b6e0, 0x9ce2ab57, 0x91a18d8e, 0x95609039, + 0x8b27c03c, 0x8fe6dd8b, 0x82a5fb52, 0x8664e6e5, 0xbe2b5b58, 0xbaea46ef, + 0xb7a96036, 0xb3687d81, 0xad2f2d84, 0xa9ee3033, 0xa4ad16ea, 0xa06c0b5d, + 0xd4326d90, 0xd0f37027, 0xddb056fe, 0xd9714b49, 0xc7361b4c, 0xc3f706fb, + 0xceb42022, 0xca753d95, 0xf23a8028, 0xf6fb9d9f, 0xfbb8bb46, 0xff79a6f1, + 0xe13ef6f4, 0xe5ffeb43, 0xe8bccd9a, 0xec7dd02d, 0x34867077, 0x30476dc0, + 0x3d044b19, 0x39c556ae, 0x278206ab, 0x23431b1c, 0x2e003dc5, 0x2ac12072, + 0x128e9dcf, 0x164f8078, 0x1b0ca6a1, 0x1fcdbb16, 0x018aeb13, 0x054bf6a4, + 0x0808d07d, 0x0cc9cdca, 0x7897ab07, 0x7c56b6b0, 0x71159069, 0x75d48dde, + 0x6b93dddb, 0x6f52c06c, 0x6211e6b5, 0x66d0fb02, 0x5e9f46bf, 0x5a5e5b08, + 0x571d7dd1, 0x53dc6066, 0x4d9b3063, 0x495a2dd4, 0x44190b0d, 0x40d816ba, + 0xaca5c697, 0xa864db20, 0xa527fdf9, 0xa1e6e04e, 0xbfa1b04b, 0xbb60adfc, + 0xb6238b25, 0xb2e29692, 0x8aad2b2f, 0x8e6c3698, 0x832f1041, 0x87ee0df6, + 0x99a95df3, 0x9d684044, 0x902b669d, 0x94ea7b2a, 0xe0b41de7, 0xe4750050, + 0xe9362689, 0xedf73b3e, 0xf3b06b3b, 0xf771768c, 0xfa325055, 0xfef34de2, + 0xc6bcf05f, 0xc27dede8, 0xcf3ecb31, 0xcbffd686, 0xd5b88683, 0xd1799b34, + 0xdc3abded, 0xd8fba05a, 0x690ce0ee, 0x6dcdfd59, 0x608edb80, 0x644fc637, + 0x7a089632, 0x7ec98b85, 0x738aad5c, 0x774bb0eb, 0x4f040d56, 0x4bc510e1, + 0x46863638, 0x42472b8f, 0x5c007b8a, 0x58c1663d, 0x558240e4, 0x51435d53, + 0x251d3b9e, 0x21dc2629, 0x2c9f00f0, 0x285e1d47, 0x36194d42, 0x32d850f5, + 0x3f9b762c, 0x3b5a6b9b, 0x0315d626, 0x07d4cb91, 0x0a97ed48, 0x0e56f0ff, + 0x1011a0fa, 0x14d0bd4d, 0x19939b94, 0x1d528623, 0xf12f560e, 0xf5ee4bb9, + 0xf8ad6d60, 0xfc6c70d7, 0xe22b20d2, 0xe6ea3d65, 0xeba91bbc, 0xef68060b, + 0xd727bbb6, 0xd3e6a601, 0xdea580d8, 0xda649d6f, 0xc423cd6a, 0xc0e2d0dd, + 0xcda1f604, 0xc960ebb3, 0xbd3e8d7e, 0xb9ff90c9, 0xb4bcb610, 0xb07daba7, + 0xae3afba2, 0xaafbe615, 0xa7b8c0cc, 0xa379dd7b, 0x9b3660c6, 0x9ff77d71, + 0x92b45ba8, 0x9675461f, 0x8832161a, 0x8cf30bad, 0x81b02d74, 0x857130c3, + 0x5d8a9099, 0x594b8d2e, 0x5408abf7, 0x50c9b640, 0x4e8ee645, 0x4a4ffbf2, + 0x470cdd2b, 0x43cdc09c, 0x7b827d21, 0x7f436096, 0x7200464f, 0x76c15bf8, + 0x68860bfd, 0x6c47164a, 0x61043093, 0x65c52d24, 0x119b4be9, 0x155a565e, + 0x18197087, 0x1cd86d30, 0x029f3d35, 0x065e2082, 0x0b1d065b, 0x0fdc1bec, + 0x3793a651, 0x3352bbe6, 0x3e119d3f, 0x3ad08088, 0x2497d08d, 0x2056cd3a, + 0x2d15ebe3, 0x29d4f654, 0xc5a92679, 0xc1683bce, 0xcc2b1d17, 0xc8ea00a0, + 0xd6ad50a5, 0xd26c4d12, 0xdf2f6bcb, 0xdbee767c, 0xe3a1cbc1, 0xe760d676, + 0xea23f0af, 0xeee2ed18, 0xf0a5bd1d, 0xf464a0aa, 0xf9278673, 0xfde69bc4, + 0x89b8fd09, 0x8d79e0be, 0x803ac667, 0x84fbdbd0, 0x9abc8bd5, 0x9e7d9662, + 0x933eb0bb, 0x97ffad0c, 0xafb010b1, 0xab710d06, 0xa6322bdf, 0xa2f33668, + 0xbcb4666d, 0xb8757bda, 0xb5365d03, 0xb1f740b4}; + +// Nallocfuzz data to take a decision +uint32_t nalloc_random_state = 0; +__thread unsigned int nalloc_running = 0; +bool nalloc_initialized = false; +uint32_t nalloc_runs = 0; + +// Nalloc fuzz parameters +uint32_t nalloc_bitmask = 0xFF; +uint32_t nalloc_magic = 0x294cee63; +bool nalloc_verbose = false; + +#ifdef NALLOC_ASAN +extern void __sanitizer_print_stack_trace(void); +#endif + +#ifdef NALLOC_LIBBACKTRACE +#define BACKTRACE_OK 0 +#define BACKTRACE_LIMIT 1 +#define BACKTRACE_EXCLUDE 2 + +void *nalloc_backtrace_state; + +struct nalloc_backtrace_data { + size_t index; + size_t max; +}; + +void nalloc_error_callback_create(void *data, const char *msg, int errnum) { + fprintf(stderr, "%s", msg); + if (errnum > 0) { + fprintf(stderr, ": %s", strerror(errnum)); + } + fprintf(stderr, "\n"); +} + +static void nalloc_backtrace_error_donothing(void *vdata, const char *msg, + int errnum) { + // do nothing +} + +static int nalloc_backtrace_cb_exclude(void *vdata, uintptr_t pc, + const char *filename, int lineno, + const char *function) { + struct backtrace_data *data = (struct backtrace_data *)vdata; + if (data->index > data->max) { + return BACKTRACE_LIMIT; + } + data->index++; + if (filename == NULL) { + if (data->index == data->max) { + return BACKTRACE_EXCLUDE; + } + return BACKTRACE_OK; + } + if (function != NULL && + (strncmp(function, "__interceptor", strlen("__interceptor")) == 0 || + strncmp(function, "___interceptor", strlen("___interceptor")) == 0 || + strncmp(function, "__sanitizer", strlen("__sanitizer")) == 0)) { + return BACKTRACE_EXCLUDE; + } + return BACKTRACE_OK; +} + +static int nalloc_backtrace_cb_print(void *vdata, uintptr_t pc, + const char *filename, int lineno, + const char *function) { + struct backtrace_data *data = (struct backtrace_data *)vdata; + if (data->index >= data->max) { + return BACKTRACE_LIMIT; + } + data->index++; + fprintf(stderr, "#%zu 0x%lx in %s %s:%d\n", data->index, pc, function, + filename, lineno); + return BACKTRACE_OK; +} + +#endif + +// Generic init, using env variables to get parameters +void nalloc_init(const char *prog) { + if (nalloc_initialized) { + return; + } + nalloc_initialized = true; + char *bitmask = getenv("NALLOC_FREQ"); + if (bitmask) { + int shift = atoi(bitmask); + if (shift > 0 && shift < 31) { + nalloc_bitmask = 1 << shift; + } + } + + char *magic = getenv("NALLOC_MAGIC"); + if (magic) { + nalloc_magic = (uint32_t)strtol(magic, NULL, 0); + } + + char *verbose = getenv("NALLOC_VERBOSE"); + if (verbose) { + nalloc_verbose = true; + } + +#ifdef NALLOC_LIBBACKTRACE + nalloc_backtrace_state = + backtrace_create_state(prog, 1, nalloc_error_callback_create, NULL); +#endif +} + +// add one byte to the CRC +static inline void nalloc_random_update(uint8_t b) { + nalloc_random_state = + ((uint32_t)((uint32_t)nalloc_random_state << 8)) ^ + nalloc_crc32_table[((nalloc_random_state >> 24) ^ b) & 0xFF]; +} + +// Start the failure injections, using a buffer as seed +static int nalloc_start(const uint8_t *data, size_t size) { + nalloc_random_state = 0; + nalloc_runs++; + for (size_t i = 0; i < size; i++) { + nalloc_random_update(data[i]); + } + if (__sync_fetch_and_add(&nalloc_running, 1)) { + __sync_fetch_and_sub(&nalloc_running, 1); + return 0; + } + return 1; +} + +// Stop the failure injections +static void nalloc_end() { __sync_fetch_and_sub(&nalloc_running, 1); } + +static bool nalloc_backtrace_exclude(size_t size, const char *op) { +#ifdef NALLOC_LIBBACKTRACE + struct backtrace_data data; + data.index = 0; + data.max = 6; + + int r = backtrace_full(nalloc_backtrace_state, 0, nalloc_backtrace_cb_exclude, + nalloc_backtrace_error_donothing, &data); + if (r == BACKTRACE_EXCLUDE) { + return true; + } +#endif + + if (nalloc_verbose) { + fprintf(stderr, "failed %s(%zu) \n", op, size); +#ifdef NALLOC_ASAN + __sanitizer_print_stack_trace(); +#endif +#ifdef NALLOC_LIBBACKTRACE + struct backtrace_data data; + data.index = 0; + data.max = 64; + + backtrace_full(nalloc_backtrace_state, 0, nalloc_backtrace_cb_print, + nalloc_backtrace_error_donothing, &data); +#endif + } + + return false; +} + +// +static bool nalloc_fail(size_t size, const char *op) { + // do not fail before thread init + if (nalloc_runs == 0) { + return false; + } + if (__sync_fetch_and_add(&nalloc_running, 1) != 1) { + // do not fail allocations outside of fuzzer input + // and do not fail inside of this function + __sync_fetch_and_sub(&nalloc_running, 1); + return false; + } + nalloc_random_update((uint8_t)size); + if (size >= 0x100) { + nalloc_random_update((uint8_t)(size >> 8)); + if (size >= 0x10000) { + nalloc_random_update((uint8_t)(size >> 16)); + // bigger may already fail or oom + } + } + if (((nalloc_random_state ^ nalloc_magic) & nalloc_bitmask) == 0) { + if (nalloc_backtrace_exclude(size, op)) { + __sync_fetch_and_sub(&nalloc_running, 1); + return false; + } + __sync_fetch_and_sub(&nalloc_running, 1); + return true; + } + __sync_fetch_and_sub(&nalloc_running, 1); + return false; +} + +// ASAN interceptor for libc routines +#ifdef NALLOC_ASAN +extern void *__interceptor_malloc(size_t); +extern void *__interceptor_calloc(size_t, size_t); +extern void *__interceptor_realloc(void *, size_t); +extern void *__interceptor_reallocarray(void *, size_t, size_t); + +extern ssize_t __interceptor_read(int, void *, size_t); +extern ssize_t __interceptor_write(int, const void *, size_t); +extern ssize_t __interceptor_recv(int, void *, size_t, int); +extern ssize_t __interceptor_send(int, const void *, size_t, int); + +#define nalloc_malloc(s) __interceptor_malloc(s) +#define nalloc_calloc(s, n) __interceptor_calloc(s, n) +#define nalloc_realloc(p, s) __interceptor_realloc(p, s) +#define nalloc_reallocarray(p, s, n) __interceptor_reallocarray(p, s, n) + +#define nalloc_read(f, b, s) __interceptor_read(f, b, s) +#define nalloc_write(f, b, s) __interceptor_write(f, b, s) +#define nalloc_recv(f, b, s, x) __interceptor_recv(f, b, s, x) +#define nalloc_send(f, b, s, x) __interceptor_send(f, b, s, x) + +#else +extern void *__libc_malloc(size_t); +extern void *__libc_calloc(size_t, size_t); +extern void *__libc_realloc(void *, size_t); +extern void *__libc_reallocarray(void *, size_t, size_t); + +extern ssize_t __read(int, void *, size_t); +extern ssize_t __write(int, const void *, size_t); +extern ssize_t __recv(int, void *, size_t, int); +extern ssize_t __send(int, const void *, size_t, int); + +#define nalloc_malloc(s) __libc_malloc(s) +#define nalloc_calloc(s, n) __libc_calloc(s, n) +#define nalloc_realloc(p, s) __libc_realloc(p, s) +#define nalloc_reallocarray(p, s, n) __libc_reallocarray(p, s, n) + +#define nalloc_read(f, b, s) __read(f, b, s) +#define nalloc_write(f, b, s) __write(f, b, s) +#define nalloc_recv(f, b, s, x) __recv(f, b, s, x) +#define nalloc_send(f, b, s, x) __send(f, b, s, x) +#endif + +// nalloc standard function overwrites with pseudo-random failures +ssize_t read(int fd, void *buf, size_t count) { + if (nalloc_fail(count, "read")) { + errno = EIO; + return -1; + } + return nalloc_read(fd, buf, count); +} + +ssize_t write(int fd, const void *buf, size_t count) { + if (nalloc_fail(count, "write")) { + errno = EIO; + return -1; + } + return nalloc_write(fd, buf, count); +} + +ssize_t recv(int fd, void *buf, size_t count, int flags) { + if (nalloc_fail(count, "recv")) { + errno = EIO; + return -1; + } + return nalloc_recv(fd, buf, count, flags); +} + +ssize_t send(int fd, const void *buf, size_t count, int flags) { + if (nalloc_fail(count, "send")) { + errno = EIO; + return -1; + } + return nalloc_send(fd, buf, count, flags); +} + +void *calloc(size_t nmemb, size_t size) { + if (nalloc_fail(size, "calloc")) { + errno = ENOMEM; + return NULL; + } + return nalloc_calloc(nmemb, size); +} + +void *malloc(size_t size) { + if (nalloc_fail(size, "malloc")) { + errno = ENOMEM; + return NULL; + } + return nalloc_malloc(size); +} + +void *realloc(void *ptr, size_t size) { + if (nalloc_fail(size, "realloc")) { + errno = ENOMEM; + return NULL; + } + return nalloc_realloc(ptr, size); +} + +void *reallocarray(void *ptr, size_t nmemb, size_t size) { + if (nalloc_fail(size, "reallocarray")) { + errno = ENOMEM; + return NULL; + } + return nalloc_reallocarray(ptr, nmemb, size); +} + +#ifdef __cplusplus // extern "C" { +} +#endif