// https://syzkaller.appspot.com/bug?id=7b4bb10c9ddf012c9d246e0a29b55dc2917669a4 // 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 static unsigned long long procid; static void sleep_ms(uint64_t ms) { usleep(ms * 1000); } static uint64_t current_time_ms(void) { struct timespec ts; if (clock_gettime(CLOCK_MONOTONIC, &ts)) exit(1); return (uint64_t)ts.tv_sec * 1000 + (uint64_t)ts.tv_nsec / 1000000; } static void use_temporary_dir(void) { char tmpdir_template[] = "./syzkaller.XXXXXX"; char* tmpdir = mkdtemp(tmpdir_template); if (!tmpdir) exit(1); if (chmod(tmpdir, 0777)) exit(1); if (chdir(tmpdir)) exit(1); } 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 void netlink_nest(struct nlmsg* nlmsg, int typ) { struct nlattr* attr = (struct nlattr*)nlmsg->pos; attr->nla_type = typ; nlmsg->pos += sizeof(*attr); nlmsg->nested[nlmsg->nesting++] = attr; } static void netlink_done(struct nlmsg* nlmsg) { struct nlattr* attr = nlmsg->nested[--nlmsg->nesting]; attr->nla_len = nlmsg->pos - (char*)attr; } 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 unsigned int queue_count = 2; static void netlink_add_device_impl(struct nlmsg* nlmsg, const char* type, const char* name, bool up) { struct ifinfomsg hdr; memset(&hdr, 0, sizeof(hdr)); if (up) hdr.ifi_flags = hdr.ifi_change = IFF_UP; netlink_init(nlmsg, RTM_NEWLINK, NLM_F_EXCL | NLM_F_CREATE, &hdr, sizeof(hdr)); if (name) netlink_attr(nlmsg, IFLA_IFNAME, name, strlen(name)); netlink_attr(nlmsg, IFLA_NUM_TX_QUEUES, &queue_count, sizeof(queue_count)); netlink_attr(nlmsg, IFLA_NUM_RX_QUEUES, &queue_count, sizeof(queue_count)); netlink_nest(nlmsg, IFLA_LINKINFO); netlink_attr(nlmsg, IFLA_INFO_KIND, type, strlen(type)); } 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 struct nlmsg nlmsg; static int runcmdline(char* cmdline) { int ret = system(cmdline); if (ret) { } return ret; } #define MAX_FDS 30 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 & ~O_CREAT, 0); } } #define XT_TABLE_SIZE 1536 #define XT_MAX_ENTRIES 10 struct xt_counters { uint64_t pcnt, bcnt; }; struct ipt_getinfo { char name[32]; unsigned int valid_hooks; unsigned int hook_entry[5]; unsigned int underflow[5]; unsigned int num_entries; unsigned int size; }; struct ipt_get_entries { char name[32]; unsigned int size; uint64_t entrytable[XT_TABLE_SIZE / sizeof(uint64_t)]; }; struct ipt_replace { char name[32]; unsigned int valid_hooks; unsigned int num_entries; unsigned int size; unsigned int hook_entry[5]; unsigned int underflow[5]; unsigned int num_counters; struct xt_counters* counters; uint64_t entrytable[XT_TABLE_SIZE / sizeof(uint64_t)]; }; struct ipt_table_desc { const char* name; struct ipt_getinfo info; struct ipt_replace replace; }; static struct ipt_table_desc ipv4_tables[] = { {.name = "filter"}, {.name = "nat"}, {.name = "mangle"}, {.name = "raw"}, {.name = "security"}, }; static struct ipt_table_desc ipv6_tables[] = { {.name = "filter"}, {.name = "nat"}, {.name = "mangle"}, {.name = "raw"}, {.name = "security"}, }; #define IPT_BASE_CTL 64 #define IPT_SO_SET_REPLACE (IPT_BASE_CTL) #define IPT_SO_GET_INFO (IPT_BASE_CTL) #define IPT_SO_GET_ENTRIES (IPT_BASE_CTL + 1) struct arpt_getinfo { char name[32]; unsigned int valid_hooks; unsigned int hook_entry[3]; unsigned int underflow[3]; unsigned int num_entries; unsigned int size; }; struct arpt_get_entries { char name[32]; unsigned int size; uint64_t entrytable[XT_TABLE_SIZE / sizeof(uint64_t)]; }; struct arpt_replace { char name[32]; unsigned int valid_hooks; unsigned int num_entries; unsigned int size; unsigned int hook_entry[3]; unsigned int underflow[3]; unsigned int num_counters; struct xt_counters* counters; uint64_t entrytable[XT_TABLE_SIZE / sizeof(uint64_t)]; }; struct arpt_table_desc { const char* name; struct arpt_getinfo info; struct arpt_replace replace; }; static struct arpt_table_desc arpt_tables[] = { {.name = "filter"}, }; #define ARPT_BASE_CTL 96 #define ARPT_SO_SET_REPLACE (ARPT_BASE_CTL) #define ARPT_SO_GET_INFO (ARPT_BASE_CTL) #define ARPT_SO_GET_ENTRIES (ARPT_BASE_CTL + 1) static void checkpoint_iptables(struct ipt_table_desc* tables, int num_tables, int family, int level) { int fd = socket(family, SOCK_STREAM, IPPROTO_TCP); if (fd == -1) { switch (errno) { case EAFNOSUPPORT: case ENOPROTOOPT: case ENOENT: return; } exit(1); } for (int i = 0; i < num_tables; i++) { struct ipt_table_desc* table = &tables[i]; strcpy(table->info.name, table->name); strcpy(table->replace.name, table->name); socklen_t optlen = sizeof(table->info); if (getsockopt(fd, level, IPT_SO_GET_INFO, &table->info, &optlen)) { switch (errno) { case EPERM: case ENOENT: case ENOPROTOOPT: continue; } exit(1); } if (table->info.size > sizeof(table->replace.entrytable)) exit(1); if (table->info.num_entries > XT_MAX_ENTRIES) exit(1); struct ipt_get_entries entries; memset(&entries, 0, sizeof(entries)); strcpy(entries.name, table->name); entries.size = table->info.size; optlen = sizeof(entries) - sizeof(entries.entrytable) + table->info.size; if (getsockopt(fd, level, IPT_SO_GET_ENTRIES, &entries, &optlen)) exit(1); table->replace.valid_hooks = table->info.valid_hooks; table->replace.num_entries = table->info.num_entries; table->replace.size = table->info.size; memcpy(table->replace.hook_entry, table->info.hook_entry, sizeof(table->replace.hook_entry)); memcpy(table->replace.underflow, table->info.underflow, sizeof(table->replace.underflow)); memcpy(table->replace.entrytable, entries.entrytable, table->info.size); } close(fd); } static void reset_iptables(struct ipt_table_desc* tables, int num_tables, int family, int level) { int fd = socket(family, SOCK_STREAM, IPPROTO_TCP); if (fd == -1) { switch (errno) { case EAFNOSUPPORT: case ENOPROTOOPT: case ENOENT: return; } exit(1); } for (int i = 0; i < num_tables; i++) { struct ipt_table_desc* table = &tables[i]; if (table->info.valid_hooks == 0) continue; struct ipt_getinfo info; memset(&info, 0, sizeof(info)); strcpy(info.name, table->name); socklen_t optlen = sizeof(info); if (getsockopt(fd, level, IPT_SO_GET_INFO, &info, &optlen)) exit(1); if (memcmp(&table->info, &info, sizeof(table->info)) == 0) { struct ipt_get_entries entries; memset(&entries, 0, sizeof(entries)); strcpy(entries.name, table->name); entries.size = table->info.size; optlen = sizeof(entries) - sizeof(entries.entrytable) + entries.size; if (getsockopt(fd, level, IPT_SO_GET_ENTRIES, &entries, &optlen)) exit(1); if (memcmp(table->replace.entrytable, entries.entrytable, table->info.size) == 0) continue; } struct xt_counters counters[XT_MAX_ENTRIES]; table->replace.num_counters = info.num_entries; table->replace.counters = counters; optlen = sizeof(table->replace) - sizeof(table->replace.entrytable) + table->replace.size; if (setsockopt(fd, level, IPT_SO_SET_REPLACE, &table->replace, optlen)) exit(1); } close(fd); } static void checkpoint_arptables(void) { int fd = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP); if (fd == -1) { switch (errno) { case EAFNOSUPPORT: case ENOPROTOOPT: case ENOENT: return; } exit(1); } for (unsigned i = 0; i < sizeof(arpt_tables) / sizeof(arpt_tables[0]); i++) { struct arpt_table_desc* table = &arpt_tables[i]; strcpy(table->info.name, table->name); strcpy(table->replace.name, table->name); socklen_t optlen = sizeof(table->info); if (getsockopt(fd, SOL_IP, ARPT_SO_GET_INFO, &table->info, &optlen)) { switch (errno) { case EPERM: case ENOENT: case ENOPROTOOPT: continue; } exit(1); } if (table->info.size > sizeof(table->replace.entrytable)) exit(1); if (table->info.num_entries > XT_MAX_ENTRIES) exit(1); struct arpt_get_entries entries; memset(&entries, 0, sizeof(entries)); strcpy(entries.name, table->name); entries.size = table->info.size; optlen = sizeof(entries) - sizeof(entries.entrytable) + table->info.size; if (getsockopt(fd, SOL_IP, ARPT_SO_GET_ENTRIES, &entries, &optlen)) exit(1); table->replace.valid_hooks = table->info.valid_hooks; table->replace.num_entries = table->info.num_entries; table->replace.size = table->info.size; memcpy(table->replace.hook_entry, table->info.hook_entry, sizeof(table->replace.hook_entry)); memcpy(table->replace.underflow, table->info.underflow, sizeof(table->replace.underflow)); memcpy(table->replace.entrytable, entries.entrytable, table->info.size); } close(fd); } static void reset_arptables() { int fd = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP); if (fd == -1) { switch (errno) { case EAFNOSUPPORT: case ENOPROTOOPT: case ENOENT: return; } exit(1); } for (unsigned i = 0; i < sizeof(arpt_tables) / sizeof(arpt_tables[0]); i++) { struct arpt_table_desc* table = &arpt_tables[i]; if (table->info.valid_hooks == 0) continue; struct arpt_getinfo info; memset(&info, 0, sizeof(info)); strcpy(info.name, table->name); socklen_t optlen = sizeof(info); if (getsockopt(fd, SOL_IP, ARPT_SO_GET_INFO, &info, &optlen)) exit(1); if (memcmp(&table->info, &info, sizeof(table->info)) == 0) { struct arpt_get_entries entries; memset(&entries, 0, sizeof(entries)); strcpy(entries.name, table->name); entries.size = table->info.size; optlen = sizeof(entries) - sizeof(entries.entrytable) + entries.size; if (getsockopt(fd, SOL_IP, ARPT_SO_GET_ENTRIES, &entries, &optlen)) exit(1); if (memcmp(table->replace.entrytable, entries.entrytable, table->info.size) == 0) continue; } else { } struct xt_counters counters[XT_MAX_ENTRIES]; table->replace.num_counters = info.num_entries; table->replace.counters = counters; optlen = sizeof(table->replace) - sizeof(table->replace.entrytable) + table->replace.size; if (setsockopt(fd, SOL_IP, ARPT_SO_SET_REPLACE, &table->replace, optlen)) exit(1); } close(fd); } #define NF_BR_NUMHOOKS 6 #define EBT_TABLE_MAXNAMELEN 32 #define EBT_CHAIN_MAXNAMELEN 32 #define EBT_BASE_CTL 128 #define EBT_SO_SET_ENTRIES (EBT_BASE_CTL) #define EBT_SO_GET_INFO (EBT_BASE_CTL) #define EBT_SO_GET_ENTRIES (EBT_SO_GET_INFO + 1) #define EBT_SO_GET_INIT_INFO (EBT_SO_GET_ENTRIES + 1) #define EBT_SO_GET_INIT_ENTRIES (EBT_SO_GET_INIT_INFO + 1) struct ebt_replace { char name[EBT_TABLE_MAXNAMELEN]; unsigned int valid_hooks; unsigned int nentries; unsigned int entries_size; struct ebt_entries* hook_entry[NF_BR_NUMHOOKS]; unsigned int num_counters; struct ebt_counter* counters; char* entries; }; struct ebt_entries { unsigned int distinguisher; char name[EBT_CHAIN_MAXNAMELEN]; unsigned int counter_offset; int policy; unsigned int nentries; char data[0] __attribute__((aligned(__alignof__(struct ebt_replace)))); }; struct ebt_table_desc { const char* name; struct ebt_replace replace; char entrytable[XT_TABLE_SIZE]; }; static struct ebt_table_desc ebt_tables[] = { {.name = "filter"}, {.name = "nat"}, {.name = "broute"}, }; static void checkpoint_ebtables(void) { int fd = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP); if (fd == -1) { switch (errno) { case EAFNOSUPPORT: case ENOPROTOOPT: case ENOENT: return; } exit(1); } for (size_t i = 0; i < sizeof(ebt_tables) / sizeof(ebt_tables[0]); i++) { struct ebt_table_desc* table = &ebt_tables[i]; strcpy(table->replace.name, table->name); socklen_t optlen = sizeof(table->replace); if (getsockopt(fd, SOL_IP, EBT_SO_GET_INIT_INFO, &table->replace, &optlen)) { switch (errno) { case EPERM: case ENOENT: case ENOPROTOOPT: continue; } exit(1); } if (table->replace.entries_size > sizeof(table->entrytable)) exit(1); table->replace.num_counters = 0; table->replace.entries = table->entrytable; optlen = sizeof(table->replace) + table->replace.entries_size; if (getsockopt(fd, SOL_IP, EBT_SO_GET_INIT_ENTRIES, &table->replace, &optlen)) exit(1); } close(fd); } static void reset_ebtables() { int fd = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP); if (fd == -1) { switch (errno) { case EAFNOSUPPORT: case ENOPROTOOPT: case ENOENT: return; } exit(1); } for (unsigned i = 0; i < sizeof(ebt_tables) / sizeof(ebt_tables[0]); i++) { struct ebt_table_desc* table = &ebt_tables[i]; if (table->replace.valid_hooks == 0) continue; struct ebt_replace replace; memset(&replace, 0, sizeof(replace)); strcpy(replace.name, table->name); socklen_t optlen = sizeof(replace); if (getsockopt(fd, SOL_IP, EBT_SO_GET_INFO, &replace, &optlen)) exit(1); replace.num_counters = 0; table->replace.entries = 0; for (unsigned h = 0; h < NF_BR_NUMHOOKS; h++) table->replace.hook_entry[h] = 0; if (memcmp(&table->replace, &replace, sizeof(table->replace)) == 0) { char entrytable[XT_TABLE_SIZE]; memset(&entrytable, 0, sizeof(entrytable)); replace.entries = entrytable; optlen = sizeof(replace) + replace.entries_size; if (getsockopt(fd, SOL_IP, EBT_SO_GET_ENTRIES, &replace, &optlen)) exit(1); if (memcmp(table->entrytable, entrytable, replace.entries_size) == 0) continue; } for (unsigned j = 0, h = 0; h < NF_BR_NUMHOOKS; h++) { if (table->replace.valid_hooks & (1 << h)) { table->replace.hook_entry[h] = (struct ebt_entries*)table->entrytable + j; j++; } } table->replace.entries = table->entrytable; optlen = sizeof(table->replace) + table->replace.entries_size; if (setsockopt(fd, SOL_IP, EBT_SO_SET_ENTRIES, &table->replace, optlen)) exit(1); } close(fd); } static void checkpoint_net_namespace(void) { checkpoint_ebtables(); checkpoint_arptables(); checkpoint_iptables(ipv4_tables, sizeof(ipv4_tables) / sizeof(ipv4_tables[0]), AF_INET, SOL_IP); checkpoint_iptables(ipv6_tables, sizeof(ipv6_tables) / sizeof(ipv6_tables[0]), AF_INET6, SOL_IPV6); } static void reset_net_namespace(void) { reset_ebtables(); reset_arptables(); reset_iptables(ipv4_tables, sizeof(ipv4_tables) / sizeof(ipv4_tables[0]), AF_INET, SOL_IP); reset_iptables(ipv6_tables, sizeof(ipv6_tables) / sizeof(ipv6_tables[0]), AF_INET6, SOL_IPV6); } 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)) { } } 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"); sandbox_common_mount_tmpfs(); loop(); exit(1); } #define FS_IOC_SETFLAGS _IOW('f', 2, long) static void remove_dir(const char* dir) { int iter = 0; DIR* dp = 0; const int umount_flags = MNT_FORCE | UMOUNT_NOFOLLOW; retry: while (umount2(dir, umount_flags) == 0) { } dp = opendir(dir); if (dp == NULL) { if (errno == EMFILE) { exit(1); } exit(1); } struct dirent* ep = 0; while ((ep = readdir(dp))) { if (strcmp(ep->d_name, ".") == 0 || strcmp(ep->d_name, "..") == 0) continue; char filename[FILENAME_MAX]; snprintf(filename, sizeof(filename), "%s/%s", dir, ep->d_name); while (umount2(filename, umount_flags) == 0) { } struct stat st; if (lstat(filename, &st)) exit(1); if (S_ISDIR(st.st_mode)) { remove_dir(filename); continue; } int i; for (i = 0;; i++) { if (unlink(filename) == 0) break; if (errno == EPERM) { int fd = open(filename, O_RDONLY); if (fd != -1) { long flags = 0; if (ioctl(fd, FS_IOC_SETFLAGS, &flags) == 0) { } close(fd); continue; } } if (errno == EROFS) { break; } if (errno != EBUSY || i > 100) exit(1); if (umount2(filename, umount_flags)) exit(1); } } closedir(dp); for (int i = 0;; i++) { if (rmdir(dir) == 0) break; if (i < 100) { if (errno == EPERM) { int fd = open(dir, O_RDONLY); if (fd != -1) { long flags = 0; if (ioctl(fd, FS_IOC_SETFLAGS, &flags) == 0) { } close(fd); continue; } } if (errno == EROFS) { break; } if (errno == EBUSY) { if (umount2(dir, umount_flags)) exit(1); continue; } if (errno == ENOTEMPTY) { if (iter < 100) { iter++; goto retry; } } } exit(1); } } static void kill_and_wait(int pid, int* status) { kill(-pid, SIGKILL); kill(pid, SIGKILL); for (int i = 0; i < 100; i++) { if (waitpid(-1, status, WNOHANG | __WALL) == pid) return; usleep(1000); } DIR* dir = opendir("/sys/fs/fuse/connections"); if (dir) { for (;;) { struct dirent* ent = readdir(dir); if (!ent) break; if (strcmp(ent->d_name, ".") == 0 || strcmp(ent->d_name, "..") == 0) continue; char abort[300]; snprintf(abort, sizeof(abort), "/sys/fs/fuse/connections/%s/abort", ent->d_name); int fd = open(abort, O_WRONLY); if (fd == -1) { continue; } if (write(fd, abort, 1) < 0) { } close(fd); } closedir(dir); } else { } while (waitpid(-1, status, __WALL) != pid) { } } static void setup_loop() { checkpoint_net_namespace(); } static void reset_loop() { reset_net_namespace(); } static void setup_test() { prctl(PR_SET_PDEATHSIG, SIGKILL, 0, 0, 0); setpgrp(); write_file("/proc/self/oom_score_adj", "1000"); if (symlink("/dev/binderfs", "./binderfs")) { } } static void close_fds() { for (int fd = 3; fd < MAX_FDS; fd++) close(fd); } #define NL802154_CMD_SET_SHORT_ADDR 11 #define NL802154_ATTR_IFINDEX 3 #define NL802154_ATTR_SHORT_ADDR 10 static const char* setup_802154() { const char* error = NULL; int sock_generic = -1; int sock_route = socket(AF_NETLINK, SOCK_RAW, NETLINK_ROUTE); if (sock_route == -1) { error = "socket(AF_NETLINK, SOCK_RAW, NETLINK_ROUTE) failed"; goto fail; } sock_generic = socket(AF_NETLINK, SOCK_RAW, NETLINK_GENERIC); if (sock_generic == -1) { error = "socket(AF_NETLINK, SOCK_RAW, NETLINK_GENERIC) failed"; goto fail; } { int nl802154_family_id = netlink_query_family_id(&nlmsg, sock_generic, "nl802154", true); if (nl802154_family_id < 0) { error = "netlink_query_family_id failed"; goto fail; } for (int i = 0; i < 2; i++) { char devname[] = "wpan0"; devname[strlen(devname) - 1] += i; uint64_t hwaddr = 0xaaaaaaaaaaaa0002 + (i << 8); uint16_t shortaddr = 0xaaa0 + i; int ifindex = if_nametoindex(devname); struct genlmsghdr genlhdr; memset(&genlhdr, 0, sizeof(genlhdr)); genlhdr.cmd = NL802154_CMD_SET_SHORT_ADDR; netlink_init(&nlmsg, nl802154_family_id, 0, &genlhdr, sizeof(genlhdr)); netlink_attr(&nlmsg, NL802154_ATTR_IFINDEX, &ifindex, sizeof(ifindex)); netlink_attr(&nlmsg, NL802154_ATTR_SHORT_ADDR, &shortaddr, sizeof(shortaddr)); if (netlink_send(&nlmsg, sock_generic) < 0) { error = "NL802154_CMD_SET_SHORT_ADDR failed"; goto fail; } netlink_device_change(&nlmsg, sock_route, devname, true, 0, &hwaddr, sizeof(hwaddr), 0); if (i == 0) { netlink_add_device_impl(&nlmsg, "lowpan", "lowpan0", false); netlink_done(&nlmsg); netlink_attr(&nlmsg, IFLA_LINK, &ifindex, sizeof(ifindex)); if (netlink_send(&nlmsg, sock_route) < 0) { error = "netlink: adding device lowpan0 type lowpan link wpan0"; goto fail; } } } } fail: close(sock_route); close(sock_generic); return error; } #define SWAP_FILE "./swap-file" #define SWAP_FILE_SIZE (128 * 1000 * 1000) static const char* setup_swap() { swapoff(SWAP_FILE); unlink(SWAP_FILE); int fd = open(SWAP_FILE, O_CREAT | O_WRONLY | O_CLOEXEC, 0600); if (fd == -1) return "swap file open failed"; fallocate(fd, FALLOC_FL_ZERO_RANGE, 0, SWAP_FILE_SIZE); close(fd); char cmdline[64]; sprintf(cmdline, "mkswap %s", SWAP_FILE); if (runcmdline(cmdline)) return "mkswap failed"; if (swapon(SWAP_FILE, SWAP_FLAG_PREFER) == 1) return "swapon failed"; return NULL; } static void execute_one(void); #define WAIT_FLAGS __WALL static void loop(void) { setup_loop(); int iter = 0; for (;; iter++) { char cwdbuf[32]; sprintf(cwdbuf, "./%d", iter); if (mkdir(cwdbuf, 0777)) exit(1); reset_loop(); int pid = fork(); if (pid < 0) exit(1); if (pid == 0) { if (chdir(cwdbuf)) exit(1); setup_test(); execute_one(); close_fds(); exit(0); } int status = 0; uint64_t start = current_time_ms(); for (;;) { sleep_ms(10); if (waitpid(-1, &status, WNOHANG | WAIT_FLAGS) == pid) break; if (current_time_ms() - start < 5000) continue; kill_and_wait(pid, &status); break; } remove_dir(cwdbuf); } } uint64_t r[7] = {0xffffffffffffffff, 0xffffffffffffffff, 0xffffffffffffffff, 0x0, 0x0, 0x0, 0x0}; void execute_one(void) { intptr_t res = 0; if (write(1, "executing program\n", sizeof("executing program\n") - 1)) { } // syz_open_dev$dri arguments: [ // dev: ptr[in, buffer] { // buffer: {2f 64 65 76 2f 64 72 69 2f 63 61 72 64 23 00} (length 0xf) // } // id: intptr = 0x1 (8 bytes) // flags: open_flags = 0x0 (8 bytes) // ] // returns fd_dri memcpy((void*)0x200000000080, "/dev/dri/card#\000", 15); res = -1; res = syz_open_dev(/*dev=*/0x200000000080, /*id=*/1, /*flags=*/0); if (res != -1) r[0] = res; // syz_open_dev$dri arguments: [ // dev: ptr[in, buffer] { // buffer: {2f 64 65 76 2f 64 72 69 2f 63 61 72 64 23 00} (length 0xf) // } // id: intptr = 0x1ff (8 bytes) // flags: open_flags = 0x0 (8 bytes) // ] // returns fd_dri memcpy((void*)0x2000000000c0, "/dev/dri/card#\000", 15); res = -1; res = syz_open_dev(/*dev=*/0x2000000000c0, /*id=*/0x1ff, /*flags=*/0); if (res != -1) r[1] = res; // syz_open_dev$dri arguments: [ // dev: ptr[in, buffer] { // buffer: {2f 64 65 76 2f 64 72 69 2f 63 61 72 64 23 00} (length 0xf) // } // id: intptr = 0x1 (8 bytes) // flags: open_flags = 0x0 (8 bytes) // ] // returns fd_dri memcpy((void*)0x200000000080, "/dev/dri/card#\000", 15); res = -1; res = syz_open_dev(/*dev=*/0x200000000080, /*id=*/1, /*flags=*/0); if (res != -1) r[2] = res; // ioctl$DRM_IOCTL_MODE_GETRESOURCES arguments: [ // fd: fd_dri (resource) // cmd: const = 0xc04064a0 (4 bytes) // arg: ptr[inout, drm_mode_card_res] { // drm_mode_card_res { // fbid: nil // crtcid: nil // connid: ptr[out, array[drm_connector_id]] { // array[drm_connector_id] { // drm_connector_id (resource) // } // } // encid: nil // nfbid: len = 0x0 (4 bytes) // ncrtcid: len = 0x0 (4 bytes) // nconnid: len = 0x1 (4 bytes) // nencid: len = 0x0 (4 bytes) // maxw: const = 0x0 (4 bytes) // maxh: const = 0x0 (4 bytes) // minw: const = 0x0 (4 bytes) // minh: const = 0x0 (4 bytes) // } // } // ] *(uint64_t*)0x200000000540 = 0; *(uint64_t*)0x200000000548 = 0; *(uint64_t*)0x200000000550 = 0x2000000004c0; *(uint64_t*)0x200000000558 = 0; *(uint32_t*)0x200000000560 = 0; *(uint32_t*)0x200000000564 = 0; *(uint32_t*)0x200000000568 = 1; *(uint32_t*)0x20000000056c = 0; *(uint32_t*)0x200000000570 = 0; *(uint32_t*)0x200000000574 = 0; *(uint32_t*)0x200000000578 = 0; *(uint32_t*)0x20000000057c = 0; res = syscall(__NR_ioctl, /*fd=*/r[0], /*cmd=*/0xc04064a0, /*arg=*/0x200000000540ul); if (res != -1) r[3] = *(uint32_t*)0x2000000004c0; // ioctl$DRM_IOCTL_SET_CLIENT_CAP arguments: [ // fd: fd_dri (resource) // cmd: const = 0x4010640d (4 bytes) // arg: ptr[in, drm_get_cap] { // drm_get_cap { // cap: drm_cap = 0x3 (8 bytes) // val: const = 0x2 (8 bytes) // } // } // ] *(uint64_t*)0x200000000000 = 3; *(uint64_t*)0x200000000008 = 2; syscall(__NR_ioctl, /*fd=*/r[2], /*cmd=*/0x4010640d, /*arg=*/0x200000000000ul); // ioctl$DRM_IOCTL_MODE_GETPLANERESOURCES arguments: [ // fd: fd_dri (resource) // cmd: const = 0xc01064b5 (4 bytes) // arg: ptr[inout, drm_mode_get_plane_res] { // drm_mode_get_plane_res { // ids: ptr[out, array[drm_plane_id]] { // array[drm_plane_id] { // drm_plane_id (resource) // } // } // cnt: len = 0x1 (4 bytes) // pad = 0x0 (4 bytes) // } // } // ] *(uint64_t*)0x200000000140 = 0x200000000100; *(uint32_t*)0x200000000148 = 1; res = syscall(__NR_ioctl, /*fd=*/r[2], /*cmd=*/0xc01064b5, /*arg=*/0x200000000140ul); if (res != -1) r[4] = *(uint32_t*)0x200000000100; // ioctl$DRM_IOCTL_MODE_GETPLANE arguments: [ // fd: fd_dri (resource) // cmd: const = 0xc02064b6 (4 bytes) // arg: ptr[inout, drm_mode_get_plane] { // drm_mode_get_plane { // plane_id: drm_plane_id (resource) // crtc_id: drm_crtc_id (resource) // fb_id: drm_fb_id (resource) // possible_crtcs: const = 0x0 (4 bytes) // gamma_size: const = 0x0 (4 bytes) // count_format_types: len = 0x0 (4 bytes) // format_type_ptr: nil // } // } // ] *(uint32_t*)0x2000000001c0 = r[4]; *(uint32_t*)0x2000000001c4 = 0; *(uint32_t*)0x2000000001c8 = 0; *(uint32_t*)0x2000000001cc = 0; *(uint32_t*)0x2000000001d0 = 0; *(uint32_t*)0x2000000001d4 = 0; *(uint64_t*)0x2000000001d8 = 0; res = syscall(__NR_ioctl, /*fd=*/r[2], /*cmd=*/0xc02064b6, /*arg=*/0x2000000001c0ul); if (res != -1) r[5] = *(uint32_t*)0x2000000001c8; // ioctl$DRM_IOCTL_MODE_GETPLANE arguments: [ // fd: fd_dri (resource) // cmd: const = 0xc02064b6 (4 bytes) // arg: ptr[inout, drm_mode_get_plane] { // drm_mode_get_plane { // plane_id: drm_plane_id (resource) // crtc_id: drm_crtc_id (resource) // fb_id: drm_fb_id (resource) // possible_crtcs: const = 0x0 (4 bytes) // gamma_size: const = 0x0 (4 bytes) // count_format_types: len = 0x0 (4 bytes) // format_type_ptr: nil // } // } // ] *(uint32_t*)0x200000000200 = r[4]; *(uint32_t*)0x200000000204 = 0; *(uint32_t*)0x200000000208 = 0; *(uint32_t*)0x20000000020c = 0; *(uint32_t*)0x200000000210 = 0; *(uint32_t*)0x200000000214 = 0; *(uint64_t*)0x200000000218 = 0; res = syscall(__NR_ioctl, /*fd=*/r[1], /*cmd=*/0xc02064b6, /*arg=*/0x200000000200ul); if (res != -1) r[6] = *(uint32_t*)0x200000000204; // ioctl$DRM_IOCTL_MODE_SETCRTC arguments: [ // fd: fd_dri (resource) // cmd: const = 0xc06864a2 (4 bytes) // arg: ptr[in, drm_mode_crtc$DRM_IOCTL_MODE_SETCRTC] { // drm_mode_crtc$DRM_IOCTL_MODE_SETCRTC { // set_connectors_ptr: ptr[in, array[drm_connector_id]] { // array[drm_connector_id] { // drm_connector_id (resource) // } // } // count_connectors: len = 0x1 (4 bytes) // crtc_id: drm_crtc_id (resource) // fb_id: drm_fb_id (resource) // x: int32 = 0x0 (4 bytes) // y: int32 = 0x0 (4 bytes) // gamma_size: int32 = 0x0 (4 bytes) // mode_valid: int32 = 0x8 (4 bytes) // mode: drm_mode_modeinfo { // clock: int32 = 0x4 (4 bytes) // hdisplay: int16 = 0x1 (2 bytes) // hsync_start: int16 = 0x3 (2 bytes) // hsync_end: int16 = 0x69 (2 bytes) // htotal: int16 = 0x200 (2 bytes) // hskew: int16 = 0x0 (2 bytes) // vdisplay: int16 = 0x1 (2 bytes) // vsync_start: int16 = 0x5 (2 bytes) // vsync_end: int16 = 0x4dab (2 bytes) // vtotal: int16 = 0x8000 (2 bytes) // vscan: int16 = 0x300 (2 bytes) // vrefresh: int32 = 0x0 (4 bytes) // flags: int32 = 0x237 (4 bytes) // type: int32 = 0x0 (4 bytes) // name: buffer: {fe 1d 0e 22 3e de 04 a6 a7 70 f5 db e6 0b 0b d1 7b // 48 12 40 ff 8e b8 39 77 36 ec 02 68 20 8f 7d} (length 0x20) // } // } // } // ] *(uint64_t*)0x200000000400 = 0x200000000480; *(uint32_t*)0x200000000480 = r[3]; *(uint32_t*)0x200000000408 = 1; *(uint32_t*)0x20000000040c = r[6]; *(uint32_t*)0x200000000410 = r[5]; *(uint32_t*)0x200000000414 = 0; *(uint32_t*)0x200000000418 = 0; *(uint32_t*)0x20000000041c = 0; *(uint32_t*)0x200000000420 = 8; *(uint32_t*)0x200000000424 = 4; *(uint16_t*)0x200000000428 = 1; *(uint16_t*)0x20000000042a = 3; *(uint16_t*)0x20000000042c = 0x69; *(uint16_t*)0x20000000042e = 0x200; *(uint16_t*)0x200000000430 = 0; *(uint16_t*)0x200000000432 = 1; *(uint16_t*)0x200000000434 = 5; *(uint16_t*)0x200000000436 = 0x4dab; *(uint16_t*)0x200000000438 = 0x8000; *(uint16_t*)0x20000000043a = 0x300; *(uint32_t*)0x20000000043c = 0; *(uint32_t*)0x200000000440 = 0x237; *(uint32_t*)0x200000000444 = 0; memcpy((void*)0x200000000448, "\xfe\x1d\x0e\x22\x3e\xde\x04\xa6\xa7\x70\xf5\xdb\xe6\x0b\x0b\xd1\x7b" "\x48\x12\x40\xff\x8e\xb8\x39\x77\x36\xec\x02\x68\x20\x8f\x7d", 32); syscall(__NR_ioctl, /*fd=*/r[0], /*cmd=*/0xc06864a2, /*arg=*/0x200000000400ul); } 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; if ((reason = setup_802154())) { fprintf(stderr, "reproducer setup failed: 802154 injection: %s\n", reason); exit(1); } if ((reason = setup_swap())) { fprintf(stderr, "reproducer setup failed: swap: %s\n", reason); exit(1); } for (procid = 0; procid < 5; procid++) { if (fork() == 0) { use_temporary_dir(); do_sandbox_none(); } } sleep(1000000); return 0; }