// https://syzkaller.appspot.com/bug?id=598d6adcdc20699542935d0e56f6cdd5bec699b1 // autogenerated by syzkaller (https://github.com/google/syzkaller) #define _GNU_SOURCE #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #ifndef __NR_memfd_create #define __NR_memfd_create 319 #endif static unsigned long long procid; static __thread int clone_ongoing; static __thread int skip_segv; static __thread jmp_buf segv_env; static void segv_handler(int sig, siginfo_t* info, void* ctx) { if (__atomic_load_n(&clone_ongoing, __ATOMIC_RELAXED) != 0) { exit(sig); } uintptr_t addr = (uintptr_t)info->si_addr; const uintptr_t prog_start = 1 << 20; const uintptr_t prog_end = 100 << 20; int skip = __atomic_load_n(&skip_segv, __ATOMIC_RELAXED) != 0; int valid = addr < prog_start || addr > prog_end; if (skip && valid) { _longjmp(segv_env, 1); } exit(sig); } static void install_segv_handler(void) { struct sigaction sa; memset(&sa, 0, sizeof(sa)); sa.sa_handler = SIG_IGN; syscall(SYS_rt_sigaction, 0x20, &sa, NULL, 8); syscall(SYS_rt_sigaction, 0x21, &sa, NULL, 8); memset(&sa, 0, sizeof(sa)); sa.sa_sigaction = segv_handler; sa.sa_flags = SA_NODEFER | SA_SIGINFO; sigaction(SIGSEGV, &sa, NULL); sigaction(SIGBUS, &sa, NULL); } #define NONFAILING(...) \ ({ \ int ok = 1; \ __atomic_fetch_add(&skip_segv, 1, __ATOMIC_SEQ_CST); \ if (_setjmp(segv_env) == 0) { \ __VA_ARGS__; \ } else \ ok = 0; \ __atomic_fetch_sub(&skip_segv, 1, __ATOMIC_SEQ_CST); \ ok; \ }) //% This code is derived from puff.{c,h}, found in the zlib development. The //% original files come with the following copyright notice: //% Copyright (C) 2002-2013 Mark Adler, all rights reserved //% version 2.3, 21 Jan 2013 //% This software is provided 'as-is', without any express or implied //% warranty. In no event will the author be held liable for any damages //% arising from the use of this software. //% Permission is granted to anyone to use this software for any purpose, //% including commercial applications, and to alter it and redistribute it //% freely, subject to the following restrictions: //% 1. The origin of this software must not be misrepresented; you must not //% claim that you wrote the original software. If you use this software //% in a product, an acknowledgment in the product documentation would be //% appreciated but is not required. //% 2. Altered source versions must be plainly marked as such, and must not be //% misrepresented as being the original software. //% 3. This notice may not be removed or altered from any source distribution. //% Mark Adler madler@alumni.caltech.edu //% BEGIN CODE DERIVED FROM puff.{c,h} #define MAXBITS 15 #define MAXLCODES 286 #define MAXDCODES 30 #define MAXCODES (MAXLCODES + MAXDCODES) #define FIXLCODES 288 struct puff_state { unsigned char* out; unsigned long outlen; unsigned long outcnt; const unsigned char* in; unsigned long inlen; unsigned long incnt; int bitbuf; int bitcnt; jmp_buf env; }; static int puff_bits(struct puff_state* s, int need) { long val = s->bitbuf; while (s->bitcnt < need) { if (s->incnt == s->inlen) longjmp(s->env, 1); val |= (long)(s->in[s->incnt++]) << s->bitcnt; s->bitcnt += 8; } s->bitbuf = (int)(val >> need); s->bitcnt -= need; return (int)(val & ((1L << need) - 1)); } static int puff_stored(struct puff_state* s) { s->bitbuf = 0; s->bitcnt = 0; if (s->incnt + 4 > s->inlen) return 2; unsigned len = s->in[s->incnt++]; len |= s->in[s->incnt++] << 8; if (s->in[s->incnt++] != (~len & 0xff) || s->in[s->incnt++] != ((~len >> 8) & 0xff)) return -2; if (s->incnt + len > s->inlen) return 2; if (s->outcnt + len > s->outlen) return 1; for (; len--; s->outcnt++, s->incnt++) { if (s->in[s->incnt]) s->out[s->outcnt] = s->in[s->incnt]; } return 0; } struct puff_huffman { short* count; short* symbol; }; static int puff_decode(struct puff_state* s, const struct puff_huffman* h) { int first = 0; int index = 0; int bitbuf = s->bitbuf; int left = s->bitcnt; int code = first = index = 0; int len = 1; short* next = h->count + 1; while (1) { while (left--) { code |= bitbuf & 1; bitbuf >>= 1; int count = *next++; if (code - count < first) { s->bitbuf = bitbuf; s->bitcnt = (s->bitcnt - len) & 7; return h->symbol[index + (code - first)]; } index += count; first += count; first <<= 1; code <<= 1; len++; } left = (MAXBITS + 1) - len; if (left == 0) break; if (s->incnt == s->inlen) longjmp(s->env, 1); bitbuf = s->in[s->incnt++]; if (left > 8) left = 8; } return -10; } static int puff_construct(struct puff_huffman* h, const short* length, int n) { int len; for (len = 0; len <= MAXBITS; len++) h->count[len] = 0; int symbol; for (symbol = 0; symbol < n; symbol++) (h->count[length[symbol]])++; if (h->count[0] == n) return 0; int left = 1; for (len = 1; len <= MAXBITS; len++) { left <<= 1; left -= h->count[len]; if (left < 0) return left; } short offs[MAXBITS + 1]; offs[1] = 0; for (len = 1; len < MAXBITS; len++) offs[len + 1] = offs[len] + h->count[len]; for (symbol = 0; symbol < n; symbol++) if (length[symbol] != 0) h->symbol[offs[length[symbol]]++] = symbol; return left; } static int puff_codes(struct puff_state* s, const struct puff_huffman* lencode, const struct puff_huffman* distcode) { static const short lens[29] = {3, 4, 5, 6, 7, 8, 9, 10, 11, 13, 15, 17, 19, 23, 27, 31, 35, 43, 51, 59, 67, 83, 99, 115, 131, 163, 195, 227, 258}; static const short lext[29] = {0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 2, 2, 2, 2, 3, 3, 3, 3, 4, 4, 4, 4, 5, 5, 5, 5, 0}; static const short dists[30] = { 1, 2, 3, 4, 5, 7, 9, 13, 17, 25, 33, 49, 65, 97, 129, 193, 257, 385, 513, 769, 1025, 1537, 2049, 3073, 4097, 6145, 8193, 12289, 16385, 24577}; static const short dext[30] = {0, 0, 0, 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6, 7, 7, 8, 8, 9, 9, 10, 10, 11, 11, 12, 12, 13, 13}; int symbol; do { symbol = puff_decode(s, lencode); if (symbol < 0) return symbol; if (symbol < 256) { if (s->outcnt == s->outlen) return 1; if (symbol) s->out[s->outcnt] = symbol; s->outcnt++; } else if (symbol > 256) { symbol -= 257; if (symbol >= 29) return -10; int len = lens[symbol] + puff_bits(s, lext[symbol]); symbol = puff_decode(s, distcode); if (symbol < 0) return symbol; unsigned dist = dists[symbol] + puff_bits(s, dext[symbol]); if (dist > s->outcnt) return -11; if (s->outcnt + len > s->outlen) return 1; while (len--) { if (dist <= s->outcnt && s->out[s->outcnt - dist]) s->out[s->outcnt] = s->out[s->outcnt - dist]; s->outcnt++; } } } while (symbol != 256); return 0; } static int puff_fixed(struct puff_state* s) { static int virgin = 1; static short lencnt[MAXBITS + 1], lensym[FIXLCODES]; static short distcnt[MAXBITS + 1], distsym[MAXDCODES]; static struct puff_huffman lencode, distcode; if (virgin) { lencode.count = lencnt; lencode.symbol = lensym; distcode.count = distcnt; distcode.symbol = distsym; short lengths[FIXLCODES]; int symbol; for (symbol = 0; symbol < 144; symbol++) lengths[symbol] = 8; for (; symbol < 256; symbol++) lengths[symbol] = 9; for (; symbol < 280; symbol++) lengths[symbol] = 7; for (; symbol < FIXLCODES; symbol++) lengths[symbol] = 8; puff_construct(&lencode, lengths, FIXLCODES); for (symbol = 0; symbol < MAXDCODES; symbol++) lengths[symbol] = 5; puff_construct(&distcode, lengths, MAXDCODES); virgin = 0; } return puff_codes(s, &lencode, &distcode); } static int puff_dynamic(struct puff_state* s) { static const short order[19] = {16, 17, 18, 0, 8, 7, 9, 6, 10, 5, 11, 4, 12, 3, 13, 2, 14, 1, 15}; int nlen = puff_bits(s, 5) + 257; int ndist = puff_bits(s, 5) + 1; int ncode = puff_bits(s, 4) + 4; if (nlen > MAXLCODES || ndist > MAXDCODES) return -3; short lengths[MAXCODES]; int index; for (index = 0; index < ncode; index++) lengths[order[index]] = puff_bits(s, 3); for (; index < 19; index++) lengths[order[index]] = 0; short lencnt[MAXBITS + 1], lensym[MAXLCODES]; struct puff_huffman lencode = {lencnt, lensym}; int err = puff_construct(&lencode, lengths, 19); if (err != 0) return -4; index = 0; while (index < nlen + ndist) { int symbol; int len; symbol = puff_decode(s, &lencode); if (symbol < 0) return symbol; if (symbol < 16) lengths[index++] = symbol; else { len = 0; if (symbol == 16) { if (index == 0) return -5; len = lengths[index - 1]; symbol = 3 + puff_bits(s, 2); } else if (symbol == 17) symbol = 3 + puff_bits(s, 3); else symbol = 11 + puff_bits(s, 7); if (index + symbol > nlen + ndist) return -6; while (symbol--) lengths[index++] = len; } } if (lengths[256] == 0) return -9; err = puff_construct(&lencode, lengths, nlen); if (err && (err < 0 || nlen != lencode.count[0] + lencode.count[1])) return -7; short distcnt[MAXBITS + 1], distsym[MAXDCODES]; struct puff_huffman distcode = {distcnt, distsym}; err = puff_construct(&distcode, lengths + nlen, ndist); if (err && (err < 0 || ndist != distcode.count[0] + distcode.count[1])) return -8; return puff_codes(s, &lencode, &distcode); } static int puff(unsigned char* dest, unsigned long* destlen, const unsigned char* source, unsigned long sourcelen) { struct puff_state s = { .out = dest, .outlen = *destlen, .outcnt = 0, .in = source, .inlen = sourcelen, .incnt = 0, .bitbuf = 0, .bitcnt = 0, }; int err; if (setjmp(s.env) != 0) err = 2; else { int last; do { last = puff_bits(&s, 1); int type = puff_bits(&s, 2); err = type == 0 ? puff_stored(&s) : (type == 1 ? puff_fixed(&s) : (type == 2 ? puff_dynamic(&s) : -1)); if (err != 0) break; } while (!last); } *destlen = s.outcnt; return err; } //% END CODE DERIVED FROM puff.{c,h} #define ZLIB_HEADER_WIDTH 2 static int puff_zlib_to_file(const unsigned char* source, unsigned long sourcelen, int dest_fd) { if (sourcelen < ZLIB_HEADER_WIDTH) return 0; source += ZLIB_HEADER_WIDTH; sourcelen -= ZLIB_HEADER_WIDTH; const unsigned long max_destlen = 132 << 20; void* ret = mmap(0, max_destlen, PROT_WRITE | PROT_READ, MAP_PRIVATE | MAP_ANON, -1, 0); if (ret == MAP_FAILED) return -1; unsigned char* dest = (unsigned char*)ret; unsigned long destlen = max_destlen; int err = puff(dest, &destlen, source, sourcelen); if (err) { munmap(dest, max_destlen); errno = -err; return -1; } if (write(dest_fd, dest, destlen) != (ssize_t)destlen) { munmap(dest, max_destlen); return -1; } return munmap(dest, max_destlen); } static int setup_loop_device(unsigned char* data, unsigned long size, const char* loopname, int* loopfd_p) { int err = 0, loopfd = -1; int memfd = syscall(__NR_memfd_create, "syzkaller", 0); if (memfd == -1) { err = errno; goto error; } if (puff_zlib_to_file(data, size, memfd)) { err = errno; goto error_close_memfd; } loopfd = open(loopname, O_RDWR); if (loopfd == -1) { err = errno; goto error_close_memfd; } if (ioctl(loopfd, LOOP_SET_FD, memfd)) { if (errno != EBUSY) { err = errno; goto error_close_loop; } ioctl(loopfd, LOOP_CLR_FD, 0); usleep(1000); if (ioctl(loopfd, LOOP_SET_FD, memfd)) { err = errno; goto error_close_loop; } } close(memfd); *loopfd_p = loopfd; return 0; error_close_loop: close(loopfd); error_close_memfd: close(memfd); error: errno = err; return -1; } static void reset_loop_device(const char* loopname) { int loopfd = open(loopname, O_RDWR); if (loopfd == -1) { return; } if (ioctl(loopfd, LOOP_CLR_FD, 0)) { } close(loopfd); } static long syz_mount_image(volatile long fsarg, volatile long dir, volatile long flags, volatile long optsarg, volatile long change_dir, volatile unsigned long size, volatile long image) { unsigned char* data = (unsigned char*)image; int res = -1, err = 0, need_loop_device = !!size; char* mount_opts = (char*)optsarg; char* target = (char*)dir; char* fs = (char*)fsarg; char* source = NULL; char loopname[64]; if (need_loop_device) { int loopfd; memset(loopname, 0, sizeof(loopname)); snprintf(loopname, sizeof(loopname), "/dev/loop%llu", procid); if (setup_loop_device(data, size, loopname, &loopfd) == -1) return -1; close(loopfd); source = loopname; } mkdir(target, 0777); char opts[256]; memset(opts, 0, sizeof(opts)); if (strlen(mount_opts) > (sizeof(opts) - 32)) { } strncpy(opts, mount_opts, sizeof(opts) - 32); if (strcmp(fs, "iso9660") == 0) { flags |= MS_RDONLY; } else if (strncmp(fs, "ext", 3) == 0) { bool has_remount_ro = false; char* remount_ro_start = strstr(opts, "errors=remount-ro"); if (remount_ro_start != NULL) { char after = *(remount_ro_start + strlen("errors=remount-ro")); char before = remount_ro_start == opts ? '\0' : *(remount_ro_start - 1); has_remount_ro = ((before == '\0' || before == ',') && (after == '\0' || after == ',')); } if (strstr(opts, "errors=panic") || !has_remount_ro) strcat(opts, ",errors=continue"); } else if (strcmp(fs, "xfs") == 0) { strcat(opts, ",nouuid"); } else if (strncmp(fs, "gfs2", 4) == 0 && (strstr(opts, "errors=panic") || strstr(opts, "debug"))) { strcat(opts, ",errors=withdraw"); } res = mount(source, target, fs, flags, opts); if (res == -1) { err = errno; goto error_clear_loop; } res = open(target, O_RDONLY | O_DIRECTORY); if (res == -1) { err = errno; goto error_clear_loop; } if (change_dir) { res = chdir(target); if (res == -1) { err = errno; } } error_clear_loop: if (need_loop_device) reset_loop_device(loopname); errno = err; return res; } int main(void) { syscall(__NR_mmap, /*addr=*/0x1ffffffff000ul, /*len=*/0x1000, /*prot=*/0ul, /*flags=MAP_FIXED|MAP_ANONYMOUS|MAP_PRIVATE*/ 0x32ul, /*fd=*/(intptr_t)-1, /*offset=*/0ul); syscall(__NR_mmap, /*addr=*/0x200000000000ul, /*len=*/0x1000000, /*prot=PROT_WRITE|PROT_READ|PROT_EXEC*/ 7ul, /*flags=MAP_FIXED|MAP_ANONYMOUS|MAP_PRIVATE*/ 0x32ul, /*fd=*/(intptr_t)-1, /*offset=*/0ul); syscall(__NR_mmap, /*addr=*/0x200001000000ul, /*len=*/0x1000, /*prot=*/0ul, /*flags=MAP_FIXED|MAP_ANONYMOUS|MAP_PRIVATE*/ 0x32ul, /*fd=*/(intptr_t)-1, /*offset=*/0ul); const char* reason; (void)reason; install_segv_handler(); if (write(1, "executing program\n", sizeof("executing program\n") - 1)) { } // syz_mount_image$minix arguments: [ // fs: ptr[in, buffer] { // buffer: {6d 69 6e 69 78 00} (length 0x6) // } // dir: ptr[in, buffer] { // buffer: {2e 2f 66 69 6c 65 31 00} (length 0x8) // } // flags: mount_flags = 0x1810002 (8 bytes) // opts: ptr[inout, array[ANYUNION]] { // array[ANYUNION] { // } // } // chdir: int8 = 0x1 (1 bytes) // size: len = 0x1e2 (8 bytes) // img: ptr[in, buffer] { // buffer: (compressed buffer with length 0x1e2) // } // ] // returns fd_dir NONFAILING(memcpy((void*)0x200000000040, "minix\000", 6)); NONFAILING(memcpy((void*)0x200000000540, "./file1\000", 8)); NONFAILING(memcpy( (void*)0x200000000180, "\x78\x9c\xec\xdb\xcb\x4e\xd4\x50\x1c\xc7\xf1\x5f\x3b\x9d\x96\xe2\xfd\xb6" "\x71\x65\xe2\x42\x37\x4e\x75\x98\x44\xd9\xc9\x03\xf8\x02\xee\x08\x54\x42" "\x2c\x6a\xd4\x8d\xc4\x44\xd9\xf8\x1e\x3e\x86\x3b\xdf\xc4\x17\x80\x44\x9f" "\xa0\xe6\x94\xd6\xa1\xa4\xa7\x2d\x1d\x67\xca\xe5\xfb\x49\xa0\x87\x43\x7f" "\xe7\x9c\x26\xfc\xdb\x53\x92\x11\x80\x0b\xeb\x7a\xf6\xdd\x91\xa3\x61\xd6" "\x4a\xd3\xf4\xcb\x3d\x49\x2f\x5f\x48\xf2\x8a\xdf\x57\xf2\x17\xb5\x46\x00" "\xf3\x91\x3a\x87\x45\x6f\xe3\x57\x77\x2f\xd5\xa7\x00\x9c\x0d\x83\xdf\xd5" "\xfd\x81\xb5\xc0\x7f\x14\x0d\x97\xbb\x00\x70\x96\x1d\xac\x0d\xb2\x7d\xc0" "\x4f\x47\xfa\xf5\xe7\xf3\xc6\x7e\xfe\x35\x6c\xb9\x7f\x38\x58\x73\xa5\x41" "\xfe\xc3\x91\xbc\x2f\x2d\xd5\x6d\x3b\xfe\xe5\xf7\x9c\xec\x78\xd7\x93\xf6" "\x8f\xe4\x03\x95\x07\x70\xbe\x5a\x06\xfa\x7e\x98\x7f\xa0\x72\x3e\x6c\xbb" "\xfe\x7c\xfe\xe5\x63\xf9\xe5\xa6\xa0\x79\x65\x32\xf6\xdc\xec\xf0\xf0\x7e" "\x39\x7f\x49\xd2\x65\x49\x57\x24\x5d\x95\x74\x2d\x7f\xd7\xba\x21\xe9\x66" "\xc5\xfc\x9b\xc7\xe6\xbf\xd3\x72\xfd\xc0\x2c\xcc\x5f\xdf\xa8\xd4\x53\x57" "\xb6\x4e\x75\x7e\x54\x13\x09\xea\xe7\x37\xd5\xf3\x6a\x3b\x89\x1f\x37\x2d" "\xd4\x62\x98\xe7\x9f\x54\x8c\xdb\x86\x9f\xe7\xc7\x1d\xe7\x2f\xf2\x2b\x1d" "\xf3\x41\x9e\x1f\x6d\xbc\x4d\x36\xad\x67\x3d\xef\x38\x3a\x50\xcf\x9d\xd6" "\x7f\x58\x55\xdf\x4d\x1a\xeb\xdf\x6a\xfa\xef\xc3\x59\xea\xdf\xb3\xd4\x3f" "\x80\x66\x1f\x3e\xed\xbe\x5e\x4f\x92\xf8\xfd\xc9\x1b\x6e\xfd\x39\xe6\xc9" "\xd6\x71\x64\x1a\xe7\xa1\x51\x6c\x24\x4d\x8f\xb9\x4d\x37\xa7\xbe\xfd\x8f" "\xd9\xcd\x9b\x5f\xef\xd7\xde\xdc\x08\x4f\xc7\x32\xec\x8d\x9e\x6f\x4c\x00" "\xe6\x2e\xfa\xb8\xf3\x2e\x0a\xb5\xfb\x68\x7b\x67\x7d\x2b\xde\x8a\xdf\x8c" "\x27\xab\xcf\x26\x2b\xe3\xc9\xd3\xd5\x28\xdb\x97\x47\xb3\xec\xce\x01\x9c" "\x66\xd3\x87\x7e\xbb\xf3\xbd\x79\x2f\x08\x00\x00\x00\x00\x00\x00\x00\x00" "\x00\x00\x00\x9c\xd8\x2d\x49\xb7\xfb\x5e\x04\x00\x00\x00\x80\x85\x58\xc4" "\xc7\x89\xfa\xbe\x46\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00" "\x00\x00\xe0\xbc\xf8\x1b\x00\x00\xff\xff\xa8\x43\x38\xcf", 482)); NONFAILING(syz_mount_image( /*fs=*/0x200000000040, /*dir=*/0x200000000540, /*flags=MS_I_VERSION|MS_POSIXACL|MS_STRICTATIME|MS_NOSUID*/ 0x1810002, /*opts=*/0x20000000c680, /*chdir=*/1, /*size=*/0x1e2, /*img=*/0x200000000180)); // syz_mount_image$exfat arguments: [ // fs: nil // dir: ptr[in, buffer] { // buffer: {2e 2f 62 75 73 00} (length 0x6) // } // flags: mount_flags = 0x80f811 (8 bytes) // opts: nil // chdir: int8 = 0x0 (1 bytes) // size: len = 0x0 (8 bytes) // img: ptr[in, buffer] { // buffer: (compressed buffer with length 0x0) // } // ] // returns fd_dir NONFAILING(memcpy((void*)0x200000000100, "./bus\000", 6)); NONFAILING(syz_mount_image( /*fs=*/0, /*dir=*/0x200000000100, /*flags=MS_I_VERSION|MS_REC|MS_SYNCHRONOUS|MS_SILENT|MS_RDONLY|0x3800*/ 0x80f811, /*opts=*/0, /*chdir=*/0, /*size=*/0, /*img=*/0x200000000080)); // rename arguments: [ // old: ptr[in, buffer] { // buffer: {2e 2f 66 69 6c 65 30 00} (length 0x8) // } // new: ptr[in, buffer] { // buffer: {2e 2f 62 75 73 00} (length 0x6) // } // ] NONFAILING(memcpy((void*)0x200000000140, "./file0\000", 8)); NONFAILING(memcpy((void*)0x200000000280, "./bus\000", 6)); syscall(__NR_rename, /*old=*/0x200000000140ul, /*new=*/0x200000000280ul); // rmdir arguments: [ // path: ptr[in, buffer] { // buffer: {2e 2f 62 75 73 00} (length 0x6) // } // ] NONFAILING(memcpy((void*)0x2000000000c0, "./bus\000", 6)); syscall(__NR_rmdir, /*path=*/0x2000000000c0ul); return 0; }