// https://syzkaller.appspot.com/bug?id=12ead29884166e5196c2435d029aa748559f731b // 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 #include #include #include #include #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 bool write_file(const char* file, const char* what, ...) { char buf[1024]; va_list args; va_start(args, what); vsnprintf(buf, sizeof(buf), what, args); va_end(args); buf[sizeof(buf) - 1] = 0; int len = strlen(buf); int fd = open(file, O_WRONLY | O_CLOEXEC); if (fd == -1) return false; if (write(fd, buf, len) != len) { int err = errno; close(fd); errno = err; return false; } close(fd); return true; } struct nlmsg { char* pos; int nesting; struct nlattr* nested[8]; char buf[4096]; }; static void netlink_init(struct nlmsg* nlmsg, int typ, int flags, const void* data, int size) { memset(nlmsg, 0, sizeof(*nlmsg)); struct nlmsghdr* hdr = (struct nlmsghdr*)nlmsg->buf; hdr->nlmsg_type = typ; hdr->nlmsg_flags = NLM_F_REQUEST | NLM_F_ACK | flags; memcpy(hdr + 1, data, size); nlmsg->pos = (char*)(hdr + 1) + NLMSG_ALIGN(size); } static void netlink_attr(struct nlmsg* nlmsg, int typ, const void* data, int size) { struct nlattr* attr = (struct nlattr*)nlmsg->pos; attr->nla_len = sizeof(*attr) + size; attr->nla_type = typ; if (size > 0) memcpy(attr + 1, data, size); nlmsg->pos += NLMSG_ALIGN(attr->nla_len); } static int netlink_send_ext(struct nlmsg* nlmsg, int sock, uint16_t reply_type, int* reply_len, bool dofail) { if (nlmsg->pos > nlmsg->buf + sizeof(nlmsg->buf) || nlmsg->nesting) exit(1); struct nlmsghdr* hdr = (struct nlmsghdr*)nlmsg->buf; hdr->nlmsg_len = nlmsg->pos - nlmsg->buf; struct sockaddr_nl addr; memset(&addr, 0, sizeof(addr)); addr.nl_family = AF_NETLINK; ssize_t n = sendto(sock, nlmsg->buf, hdr->nlmsg_len, 0, (struct sockaddr*)&addr, sizeof(addr)); if (n != (ssize_t)hdr->nlmsg_len) { if (dofail) exit(1); return -1; } n = recv(sock, nlmsg->buf, sizeof(nlmsg->buf), 0); if (reply_len) *reply_len = 0; if (n < 0) { if (dofail) exit(1); return -1; } if (n < (ssize_t)sizeof(struct nlmsghdr)) { errno = EINVAL; if (dofail) exit(1); return -1; } if (hdr->nlmsg_type == NLMSG_DONE) return 0; if (reply_len && hdr->nlmsg_type == reply_type) { *reply_len = n; return 0; } if (n < (ssize_t)(sizeof(struct nlmsghdr) + sizeof(struct nlmsgerr))) { errno = EINVAL; if (dofail) exit(1); return -1; } if (hdr->nlmsg_type != NLMSG_ERROR) { errno = EINVAL; if (dofail) exit(1); return -1; } errno = -((struct nlmsgerr*)(hdr + 1))->error; return -errno; } static int netlink_send(struct nlmsg* nlmsg, int sock) { return netlink_send_ext(nlmsg, sock, 0, NULL, true); } static int netlink_query_family_id(struct nlmsg* nlmsg, int sock, const char* family_name, bool dofail) { struct genlmsghdr genlhdr; memset(&genlhdr, 0, sizeof(genlhdr)); genlhdr.cmd = CTRL_CMD_GETFAMILY; netlink_init(nlmsg, GENL_ID_CTRL, 0, &genlhdr, sizeof(genlhdr)); netlink_attr(nlmsg, CTRL_ATTR_FAMILY_NAME, family_name, strnlen(family_name, GENL_NAMSIZ - 1) + 1); int n = 0; int err = netlink_send_ext(nlmsg, sock, GENL_ID_CTRL, &n, dofail); if (err < 0) { return -1; } uint16_t id = 0; struct nlattr* attr = (struct nlattr*)(nlmsg->buf + NLMSG_HDRLEN + NLMSG_ALIGN(sizeof(genlhdr))); for (; (char*)attr < nlmsg->buf + n; attr = (struct nlattr*)((char*)attr + NLMSG_ALIGN(attr->nla_len))) { if (attr->nla_type == CTRL_ATTR_FAMILY_ID) { id = *(uint16_t*)(attr + 1); break; } } if (!id) { errno = EINVAL; return -1; } recv(sock, nlmsg->buf, sizeof(nlmsg->buf), 0); return id; } static void netlink_device_change(struct nlmsg* nlmsg, int sock, const char* name, bool up, const char* master, const void* mac, int macsize, const char* new_name) { struct ifinfomsg hdr; memset(&hdr, 0, sizeof(hdr)); if (up) hdr.ifi_flags = hdr.ifi_change = IFF_UP; hdr.ifi_index = if_nametoindex(name); netlink_init(nlmsg, RTM_NEWLINK, 0, &hdr, sizeof(hdr)); if (new_name) netlink_attr(nlmsg, IFLA_IFNAME, new_name, strlen(new_name)); if (master) { int ifindex = if_nametoindex(master); netlink_attr(nlmsg, IFLA_MASTER, &ifindex, sizeof(ifindex)); } if (macsize) netlink_attr(nlmsg, IFLA_ADDRESS, mac, macsize); int err = netlink_send(nlmsg, sock); if (err < 0) { } } static int netlink_add_addr(struct nlmsg* nlmsg, int sock, const char* dev, const void* addr, int addrsize) { struct ifaddrmsg hdr; memset(&hdr, 0, sizeof(hdr)); hdr.ifa_family = addrsize == 4 ? AF_INET : AF_INET6; hdr.ifa_prefixlen = addrsize == 4 ? 24 : 120; hdr.ifa_scope = RT_SCOPE_UNIVERSE; hdr.ifa_index = if_nametoindex(dev); netlink_init(nlmsg, RTM_NEWADDR, NLM_F_CREATE | NLM_F_REPLACE, &hdr, sizeof(hdr)); netlink_attr(nlmsg, IFA_LOCAL, addr, addrsize); netlink_attr(nlmsg, IFA_ADDRESS, addr, addrsize); return netlink_send(nlmsg, sock); } static void netlink_add_addr4(struct nlmsg* nlmsg, int sock, const char* dev, const char* addr) { struct in_addr in_addr; inet_pton(AF_INET, addr, &in_addr); int err = netlink_add_addr(nlmsg, sock, dev, &in_addr, sizeof(in_addr)); if (err < 0) { } } static void netlink_add_addr6(struct nlmsg* nlmsg, int sock, const char* dev, const char* addr) { struct in6_addr in6_addr; inet_pton(AF_INET6, addr, &in6_addr); int err = netlink_add_addr(nlmsg, sock, dev, &in6_addr, sizeof(in6_addr)); if (err < 0) { } } static void netlink_add_neigh(struct nlmsg* nlmsg, int sock, const char* name, const void* addr, int addrsize, const void* mac, int macsize) { struct ndmsg hdr; memset(&hdr, 0, sizeof(hdr)); hdr.ndm_family = addrsize == 4 ? AF_INET : AF_INET6; hdr.ndm_ifindex = if_nametoindex(name); hdr.ndm_state = NUD_PERMANENT; netlink_init(nlmsg, RTM_NEWNEIGH, NLM_F_EXCL | NLM_F_CREATE, &hdr, sizeof(hdr)); netlink_attr(nlmsg, NDA_DST, addr, addrsize); netlink_attr(nlmsg, NDA_LLADDR, mac, macsize); int err = netlink_send(nlmsg, sock); if (err < 0) { } } static struct nlmsg nlmsg; static int tunfd = -1; #define TUN_IFACE "syz_tun" #define LOCAL_MAC 0xaaaaaaaaaaaa #define REMOTE_MAC 0xaaaaaaaaaabb #define LOCAL_IPV4 "172.20.20.170" #define REMOTE_IPV4 "172.20.20.187" #define LOCAL_IPV6 "fe80::aa" #define REMOTE_IPV6 "fe80::bb" #define IFF_NAPI 0x0010 static void initialize_tun(void) { tunfd = open("/dev/net/tun", O_RDWR | O_NONBLOCK); if (tunfd == -1) { printf("tun: can't open /dev/net/tun: please enable CONFIG_TUN=y\n"); printf("otherwise fuzzing or reproducing might not work as intended\n"); return; } const int kTunFd = 200; if (dup2(tunfd, kTunFd) < 0) exit(1); close(tunfd); tunfd = kTunFd; struct ifreq ifr; memset(&ifr, 0, sizeof(ifr)); strncpy(ifr.ifr_name, TUN_IFACE, IFNAMSIZ); ifr.ifr_flags = IFF_TAP | IFF_NO_PI; if (ioctl(tunfd, TUNSETIFF, (void*)&ifr) < 0) { exit(1); } char sysctl[64]; sprintf(sysctl, "/proc/sys/net/ipv6/conf/%s/accept_dad", TUN_IFACE); write_file(sysctl, "0"); sprintf(sysctl, "/proc/sys/net/ipv6/conf/%s/router_solicitations", TUN_IFACE); write_file(sysctl, "0"); int sock = socket(AF_NETLINK, SOCK_RAW, NETLINK_ROUTE); if (sock == -1) exit(1); netlink_add_addr4(&nlmsg, sock, TUN_IFACE, LOCAL_IPV4); netlink_add_addr6(&nlmsg, sock, TUN_IFACE, LOCAL_IPV6); uint64_t macaddr = REMOTE_MAC; struct in_addr in_addr; inet_pton(AF_INET, REMOTE_IPV4, &in_addr); netlink_add_neigh(&nlmsg, sock, TUN_IFACE, &in_addr, sizeof(in_addr), &macaddr, ETH_ALEN); struct in6_addr in6_addr; inet_pton(AF_INET6, REMOTE_IPV6, &in6_addr); netlink_add_neigh(&nlmsg, sock, TUN_IFACE, &in6_addr, sizeof(in6_addr), &macaddr, ETH_ALEN); macaddr = LOCAL_MAC; netlink_device_change(&nlmsg, sock, TUN_IFACE, true, 0, &macaddr, ETH_ALEN, NULL); close(sock); } static long syz_open_dev(volatile long a0, volatile long a1, volatile long a2) { if (a0 == 0xc || a0 == 0xb) { char buf[128]; sprintf(buf, "/dev/%s/%d:%d", a0 == 0xc ? "char" : "block", (uint8_t)a1, (uint8_t)a2); return open(buf, O_RDWR, 0); } else { unsigned long nb = a1; char buf[1024]; char* hash; strncpy(buf, (char*)a0, sizeof(buf) - 1); buf[sizeof(buf) - 1] = 0; while ((hash = strchr(buf, '#'))) { *hash = '0' + (char)(nb % 10); nb /= 10; } return open(buf, a2, 0); } } //% 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 long syz_read_part_table(volatile unsigned long size, volatile long image) { unsigned char* data = (unsigned char*)image; int err = 0, res = -1, loopfd = -1; char loopname[64]; snprintf(loopname, sizeof(loopname), "/dev/loop%llu", procid); if (setup_loop_device(data, size, loopname, &loopfd) == -1) return -1; struct loop_info64 info; if (ioctl(loopfd, LOOP_GET_STATUS64, &info)) { err = errno; goto error_clear_loop; } info.lo_flags |= LO_FLAGS_PARTSCAN; if (ioctl(loopfd, LOOP_SET_STATUS64, &info)) { err = errno; goto error_clear_loop; } res = 0; for (unsigned long i = 1, j = 0; i < 8; i++) { snprintf(loopname, sizeof(loopname), "/dev/loop%llup%d", procid, (int)i); struct stat statbuf; if (stat(loopname, &statbuf) == 0) { char linkname[64]; snprintf(linkname, sizeof(linkname), "./file%d", (int)j++); if (symlink(loopname, linkname)) { } } } error_clear_loop: if (res) ioctl(loopfd, LOOP_CLR_FD, 0); close(loopfd); errno = err; return res; } static void setup_gadgetfs(); static void setup_binderfs(); static void setup_fusectl(); static void sandbox_common_mount_tmpfs(void) { write_file("/proc/sys/fs/mount-max", "100000"); if (mkdir("./syz-tmp", 0777)) exit(1); if (mount("", "./syz-tmp", "tmpfs", 0, NULL)) exit(1); if (mkdir("./syz-tmp/newroot", 0777)) exit(1); if (mkdir("./syz-tmp/newroot/dev", 0700)) exit(1); unsigned bind_mount_flags = MS_BIND | MS_REC | MS_PRIVATE; if (mount("/dev", "./syz-tmp/newroot/dev", NULL, bind_mount_flags, NULL)) exit(1); if (mkdir("./syz-tmp/newroot/proc", 0700)) exit(1); if (mount("syz-proc", "./syz-tmp/newroot/proc", "proc", 0, NULL)) exit(1); if (mkdir("./syz-tmp/newroot/selinux", 0700)) exit(1); const char* selinux_path = "./syz-tmp/newroot/selinux"; if (mount("/selinux", selinux_path, NULL, bind_mount_flags, NULL)) { if (errno != ENOENT) exit(1); if (mount("/sys/fs/selinux", selinux_path, NULL, bind_mount_flags, NULL) && errno != ENOENT) exit(1); } if (mkdir("./syz-tmp/newroot/sys", 0700)) exit(1); if (mount("/sys", "./syz-tmp/newroot/sys", 0, bind_mount_flags, NULL)) exit(1); if (mount("/sys/kernel/debug", "./syz-tmp/newroot/sys/kernel/debug", NULL, bind_mount_flags, NULL) && errno != ENOENT) exit(1); if (mount("/sys/fs/smackfs", "./syz-tmp/newroot/sys/fs/smackfs", NULL, bind_mount_flags, NULL) && errno != ENOENT) exit(1); if (mount("/proc/sys/fs/binfmt_misc", "./syz-tmp/newroot/proc/sys/fs/binfmt_misc", NULL, bind_mount_flags, NULL) && errno != ENOENT) exit(1); if (mkdir("./syz-tmp/newroot/syz-inputs", 0700)) exit(1); if (mount("/syz-inputs", "./syz-tmp/newroot/syz-inputs", NULL, bind_mount_flags | MS_RDONLY, NULL) && errno != ENOENT) exit(1); if (mkdir("./syz-tmp/pivot", 0777)) exit(1); if (syscall(SYS_pivot_root, "./syz-tmp", "./syz-tmp/pivot")) { if (chdir("./syz-tmp")) exit(1); } else { if (chdir("/")) exit(1); if (umount2("./pivot", MNT_DETACH)) exit(1); } if (chroot("./newroot")) exit(1); if (chdir("/")) exit(1); setup_gadgetfs(); setup_binderfs(); setup_fusectl(); } static void setup_gadgetfs() { if (mkdir("/dev/gadgetfs", 0777)) { } if (mount("gadgetfs", "/dev/gadgetfs", "gadgetfs", 0, NULL)) { } } static void setup_fusectl() { if (mount(0, "/sys/fs/fuse/connections", "fusectl", 0, 0)) { } } static void setup_binderfs() { if (mkdir("/dev/binderfs", 0777)) { } if (mount("binder", "/dev/binderfs", "binder", 0, NULL)) { } if (symlink("/dev/binderfs", "./binderfs")) { } } static void loop(); static void sandbox_common() { prctl(PR_SET_PDEATHSIG, SIGKILL, 0, 0, 0); if (getppid() == 1) exit(1); struct rlimit rlim; rlim.rlim_cur = rlim.rlim_max = (200 << 20); setrlimit(RLIMIT_AS, &rlim); rlim.rlim_cur = rlim.rlim_max = 32 << 20; setrlimit(RLIMIT_MEMLOCK, &rlim); rlim.rlim_cur = rlim.rlim_max = 136 << 20; setrlimit(RLIMIT_FSIZE, &rlim); rlim.rlim_cur = rlim.rlim_max = 1 << 20; setrlimit(RLIMIT_STACK, &rlim); rlim.rlim_cur = rlim.rlim_max = 128 << 20; setrlimit(RLIMIT_CORE, &rlim); rlim.rlim_cur = rlim.rlim_max = 256; setrlimit(RLIMIT_NOFILE, &rlim); if (unshare(CLONE_NEWNS)) { } if (mount(NULL, "/", NULL, MS_REC | MS_PRIVATE, NULL)) { } if (unshare(CLONE_NEWIPC)) { } if (unshare(0x02000000)) { } if (unshare(CLONE_NEWUTS)) { } if (unshare(CLONE_SYSVSEM)) { } typedef struct { const char* name; const char* value; } sysctl_t; static const sysctl_t sysctls[] = { {"/proc/sys/kernel/shmmax", "16777216"}, {"/proc/sys/kernel/shmall", "536870912"}, {"/proc/sys/kernel/shmmni", "1024"}, {"/proc/sys/kernel/msgmax", "8192"}, {"/proc/sys/kernel/msgmni", "1024"}, {"/proc/sys/kernel/msgmnb", "1024"}, {"/proc/sys/kernel/sem", "1024 1048576 500 1024"}, }; unsigned i; for (i = 0; i < sizeof(sysctls) / sizeof(sysctls[0]); i++) write_file(sysctls[i].name, sysctls[i].value); } static int wait_for_loop(int pid) { if (pid < 0) exit(1); int status = 0; while (waitpid(-1, &status, __WALL) != pid) { } return WEXITSTATUS(status); } static void drop_caps(void) { struct __user_cap_header_struct cap_hdr = {}; struct __user_cap_data_struct cap_data[2] = {}; cap_hdr.version = _LINUX_CAPABILITY_VERSION_3; cap_hdr.pid = getpid(); if (syscall(SYS_capget, &cap_hdr, &cap_data)) exit(1); const int drop = (1 << CAP_SYS_PTRACE) | (1 << CAP_SYS_NICE); cap_data[0].effective &= ~drop; cap_data[0].permitted &= ~drop; cap_data[0].inheritable &= ~drop; if (syscall(SYS_capset, &cap_hdr, &cap_data)) exit(1); } static int do_sandbox_none(void) { if (unshare(CLONE_NEWPID)) { } int pid = fork(); if (pid != 0) return wait_for_loop(pid); sandbox_common(); drop_caps(); if (unshare(CLONE_NEWNET)) { } write_file("/proc/sys/net/ipv4/ping_group_range", "0 65535"); initialize_tun(); sandbox_common_mount_tmpfs(); loop(); exit(1); } uint64_t r[1] = {0xffffffffffffffff}; void loop(void) { intptr_t res = 0; if (write(1, "executing program\n", sizeof("executing program\n") - 1)) { } // syz_read_part_table arguments: [ // size: len = 0x635 (8 bytes) // img: ptr[in, buffer] { // buffer: (compressed buffer with length 0x635) // } // ] memcpy( (void*)0x200000000000, "\x78\x9c\xec\xdc\x3f\x68\x5d\xe5\x1b\x07\xf0\xef\x49\xef\x3d\xf7\x26\x85" "\xb6\xbf\x1f\x4e\x5d\x52\x9d\xc5\x62\x67\x6f\x0d\x48\x7a\xa9\x74\xaa\x74" "\xeb\x52\x15\x24\x54\x1c\xe2\x54\xb1\xe4\x46\xba\x98\x21\x83\x83\xb3\x4b" "\x11\xb2\xd4\xba\x68\xe8\xe0\xa0\x2d\xe2\x24\x4e\xa1\x83\x5a\x71\x15\xa4" "\xa8\xd4\x22\x3d\x72\xee\x39\xf7\x4f\x04\x41\x6c\x3b\x08\x9f\xcf\x90\xf3" "\xbe\xcf\x79\xde\xf7\x79\x9f\x9c\x93\x31\x27\xfc\xa7\x2d\xa4\x9b\x14\xe3" "\x61\x2f\x9d\x24\xc7\x5f\xfe\x4b\xc6\x66\x26\x09\xe9\xd7\xf9\x49\xaa\x6e" "\x7b\xef\xdc\xce\xea\xa9\xd3\x55\x55\x55\x45\x9d\x73\x3e\xdd\x3c\xf9\xf9" "\xa1\xeb\x49\x3a\xed\x92\xfe\x74\x9b\xaa\xaa\x36\xa6\x93\x93\xb9\xfa\xc1" "\xd2\x8d\x77\x8b\x51\x77\xe7\x76\x5d\xf4\xe6\xd6\x81\x3a\xbc\xd8\x1c\xe3" "\x48\xf2\xf4\xc1\xb2\x3f\xde\x66\x6e\x87\x54\xd5\xbe\x83\xf5\x1e\xe5\xef" "\x81\x7f\xe7\xda\xe0\x56\x51\x5c\x29\xdb\xd9\x53\xbf\x3c\x58\x49\x3e\xfa" "\x79\xf5\xec\xee\x99\xad\xf7\xae\xbf\xd8\x86\x37\x92\x2f\x93\xfa\xf9\xbf" "\x53\xbf\x17\x93\xec\xb7\x72\xf1\xd8\x85\xce\x78\x58\x3f\xe5\x37\xe7\xf7" "\xfd\xb5\xb9\x94\xb3\xc8\xec\x71\x2f\xa6\xb3\xef\x0c\xa3\x2b\xeb\xc3\xed" "\x95\xc1\xda\xde\x24\x70\x74\xb8\xf3\xe9\x6b\xcf\xfd\x7e\xec\x46\xaa\x13" "\xf9\xaa\xec\x2c\x4c\x6e\x14\xb3\xfd\xca\x64\xf4\xf0\xed\xd7\xfd\x1f\xae" "\xdf\xfe\xed\x4b\x83\xb5\xbd\xe1\xe5\xc5\xe9\x8d\x27\xde\xff\xff\x17\x59" "\x6e\x27\x77\xab\x2a\x47\xea\x92\xff\xcb\xf8\x4f\x67\xf9\x11\x54\x06\x00" "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00" "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00" "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00" "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00" "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00" "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00" "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00" "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00" "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00" "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00" "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00" "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00" "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00" "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00" "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00" "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00" "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00" "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00" "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00" "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00" "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00" "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00" "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00" "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00" "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00" "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00" "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00" "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00" "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00" "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00" "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00" "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00" "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00" "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00" "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00" "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00" "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00" "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00" "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00" "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00" "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00" "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00" "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00" "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00" "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00" "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00" "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00" "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00" "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00" "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00" "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00" "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00" "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00" "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00" "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00" "\x00\x00\x00\x00\x00\x00\xe0\x71\xb8\x36\xb8\x95\x64\x34\xdc\x4e\xd6\xf6" "\x86\xbd\x36\xba\x7a\x76\xf7\xcc\x56\x99\xe4\x85\x57\xfb\x6d\xe8\xf8\xfc" "\xaa\x03\xed\xf5\x62\x2e\xdc\xa9\xaf\x1b\x59\x4f\x7e\xf8\x24\xdd\xf9\xa4" "\xa2\xfe\x31\x8e\x2c\xa4\xbb\xd2\xc4\xbe\x5f\xae\x9e\x19\x0f\x3a\x93\xfa" "\xbd\xc5\x66\x70\x69\xb0\xb6\x37\xbc\xbf\x94\xdc\x79\xf6\xc1\xd1\x61\xb3" "\x2a\x37\x3f\x3b\x31\x2b\xb7\x31\xdd\x79\x37\xcf\xb7\xa3\x7b\x55\x63\x3c" "\xd9\xfc\xbb\x26\xdb\x12\xd5\xe1\x26\xef\xeb\xfb\xf3\xfd\x17\x9d\x64\x7d" "\xb8\x3d\xae\x7f\xf9\xc7\xa2\xd3\x34\xfc\x71\x31\x9a\x1e\x73\x21\xc9\xeb" "\xbd\xbc\xd2\x34\x53\xdd\x2b\xdb\xb5\x7f\xcc\xda\x00\x00\x00\x00\x00\x00" "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x80\x87\xb2\x7a\xea\xf4\x1b\x77\xdb" "\xf1\xf9\x7e\x92\x9f\xde\x5e\xa8\xc7\x55\xaf\xf9\x2f\xf7\x62\xa9\xd8\x97" "\xff\x6d\x2f\x59\x3c\x99\x5c\xed\xa7\x18\xad\x24\xb9\xfd\xd2\x6f\xe5\x37" "\x87\xb6\xbe\x6b\x3f\x1d\x30\x4a\x2f\xa3\x24\x07\x3f\xdc\x3c\xd7\x2e\x29" "\xf7\x6d\x30\xfd\x44\x40\x91\xaa\x7c\x9c\x9d\xf1\x4f\xfc\x19\x00\x00\xff" "\xff\xc5\x9b\x7b\x3a", 1589); syz_read_part_table(/*size=*/0x635, /*img=*/0x200000000000); // syz_open_dev$loop arguments: [ // dev: ptr[in, buffer] { // buffer: {2f 64 65 76 2f 6c 6f 6f 70 23 00} (length 0xb) // } // id: intptr = 0x0 (8 bytes) // flags: open_flags = 0x0 (8 bytes) // ] // returns fd_loop memcpy((void*)0x200000000140, "/dev/loop#\000", 11); res = -1; res = syz_open_dev(/*dev=*/0x200000000140, /*id=*/0, /*flags=*/0); if (res != -1) r[0] = res; // ioctl$LOOP_SET_BLOCK_SIZE arguments: [ // fd: fd_loop (resource) // cmd: const = 0x4c09 (4 bytes) // arg: intptr = 0x8000 (8 bytes) // ] syscall(__NR_ioctl, /*fd=*/r[0], /*cmd=*/0x4c09, /*arg=*/0x8000ul); } int main(void) { syscall(__NR_mmap, /*addr=*/0x1ffffffff000ul, /*len=*/0x1000ul, /*prot=*/0ul, /*flags=MAP_FIXED|MAP_ANONYMOUS|MAP_PRIVATE*/ 0x32ul, /*fd=*/(intptr_t)-1, /*offset=*/0ul); syscall(__NR_mmap, /*addr=*/0x200000000000ul, /*len=*/0x1000000ul, /*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=*/0x1000ul, /*prot=*/0ul, /*flags=MAP_FIXED|MAP_ANONYMOUS|MAP_PRIVATE*/ 0x32ul, /*fd=*/(intptr_t)-1, /*offset=*/0ul); const char* reason; (void)reason; do_sandbox_none(); return 0; }