| // general protection fault in hci_uart_write_work |
| // https://syzkaller.appspot.com/bug?id=b9421f2a1c55853c340125c318152bd5cb9aa0b8 |
| // status:fixed |
| // autogenerated by syzkaller (https://github.com/google/syzkaller) |
| |
| #define _GNU_SOURCE |
| |
| #include <arpa/inet.h> |
| #include <endian.h> |
| #include <errno.h> |
| #include <fcntl.h> |
| #include <net/if.h> |
| #include <net/if_arp.h> |
| #include <netinet/in.h> |
| #include <sched.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/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 <unistd.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> |
| |
| 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; |
| } |
| |
| static struct { |
| char* pos; |
| int nesting; |
| struct nlattr* nested[8]; |
| char buf[1024]; |
| } nlmsg; |
| |
| static void netlink_init(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(int typ, const void* data, int size) |
| { |
| struct nlattr* attr = (struct nlattr*)nlmsg.pos; |
| attr->nla_len = sizeof(*attr) + size; |
| attr->nla_type = typ; |
| memcpy(attr + 1, data, size); |
| nlmsg.pos += NLMSG_ALIGN(attr->nla_len); |
| } |
| |
| static int netlink_send(int sock) |
| { |
| 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; |
| unsigned n = sendto(sock, nlmsg.buf, hdr->nlmsg_len, 0, |
| (struct sockaddr*)&addr, sizeof(addr)); |
| if (n != hdr->nlmsg_len) |
| exit(1); |
| n = recv(sock, nlmsg.buf, sizeof(nlmsg.buf), 0); |
| if (n < sizeof(struct nlmsghdr) + sizeof(struct nlmsgerr)) |
| exit(1); |
| if (hdr->nlmsg_type != NLMSG_ERROR) |
| exit(1); |
| return -((struct nlmsgerr*)(hdr + 1))->error; |
| } |
| |
| static void netlink_device_change(int sock, const char* name, bool up, |
| const char* master, const void* mac, |
| int macsize) |
| { |
| struct ifinfomsg hdr; |
| memset(&hdr, 0, sizeof(hdr)); |
| if (up) |
| hdr.ifi_flags = hdr.ifi_change = IFF_UP; |
| netlink_init(RTM_NEWLINK, 0, &hdr, sizeof(hdr)); |
| netlink_attr(IFLA_IFNAME, name, strlen(name)); |
| if (master) { |
| int ifindex = if_nametoindex(master); |
| netlink_attr(IFLA_MASTER, &ifindex, sizeof(ifindex)); |
| } |
| if (macsize) |
| netlink_attr(IFLA_ADDRESS, mac, macsize); |
| int err = netlink_send(sock); |
| (void)err; |
| } |
| |
| static int netlink_add_addr(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(RTM_NEWADDR, NLM_F_CREATE | NLM_F_REPLACE, &hdr, sizeof(hdr)); |
| netlink_attr(IFA_LOCAL, addr, addrsize); |
| netlink_attr(IFA_ADDRESS, addr, addrsize); |
| return netlink_send(sock); |
| } |
| |
| static void netlink_add_addr4(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(sock, dev, &in_addr, sizeof(in_addr)); |
| (void)err; |
| } |
| |
| static void netlink_add_addr6(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(sock, dev, &in6_addr, sizeof(in6_addr)); |
| (void)err; |
| } |
| |
| static void netlink_add_neigh(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(RTM_NEWNEIGH, NLM_F_EXCL | NLM_F_CREATE, &hdr, sizeof(hdr)); |
| netlink_attr(NDA_DST, addr, addrsize); |
| netlink_attr(NDA_LLADDR, mac, macsize); |
| int err = netlink_send(sock); |
| (void)err; |
| } |
| |
| static int tunfd = -1; |
| static int tun_frags_enabled; |
| #define SYZ_TUN_MAX_PACKET_SIZE 1000 |
| |
| #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 |
| #define IFF_NAPI_FRAGS 0x0020 |
| |
| 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 = 240; |
| 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 | IFF_NAPI | IFF_NAPI_FRAGS; |
| if (ioctl(tunfd, TUNSETIFF, (void*)&ifr) < 0) { |
| ifr.ifr_flags = IFF_TAP | IFF_NO_PI; |
| if (ioctl(tunfd, TUNSETIFF, (void*)&ifr) < 0) |
| exit(1); |
| } |
| if (ioctl(tunfd, TUNGETIFF, (void*)&ifr) < 0) |
| exit(1); |
| tun_frags_enabled = (ifr.ifr_flags & IFF_NAPI_FRAGS) != 0; |
| 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(sock, TUN_IFACE, LOCAL_IPV4); |
| netlink_add_addr6(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(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(sock, TUN_IFACE, &in6_addr, sizeof(in6_addr), &macaddr, |
| ETH_ALEN); |
| macaddr = LOCAL_MAC; |
| netlink_device_change(sock, TUN_IFACE, true, 0, &macaddr, ETH_ALEN); |
| close(sock); |
| } |
| |
| static void setup_common() |
| { |
| if (mount(0, "/sys/fs/fuse/connections", "fusectl", 0, 0)) { |
| } |
| } |
| |
| static void loop(); |
| |
| static void sandbox_common() |
| { |
| prctl(PR_SET_PDEATHSIG, SIGKILL, 0, 0, 0); |
| setpgrp(); |
| setsid(); |
| 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 = 0; |
| setrlimit(RLIMIT_CORE, &rlim); |
| rlim.rlim_cur = rlim.rlim_max = 256; |
| setrlimit(RLIMIT_NOFILE, &rlim); |
| if (unshare(CLONE_NEWNS)) { |
| } |
| 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); |
| } |
| |
| int wait_for_loop(int pid) |
| { |
| if (pid < 0) |
| exit(1); |
| int status = 0; |
| while (waitpid(-1, &status, __WALL) != pid) { |
| } |
| return WEXITSTATUS(status); |
| } |
| |
| static int do_sandbox_none(void) |
| { |
| if (unshare(CLONE_NEWPID)) { |
| } |
| int pid = fork(); |
| if (pid != 0) |
| return wait_for_loop(pid); |
| setup_common(); |
| sandbox_common(); |
| if (unshare(CLONE_NEWNET)) { |
| } |
| initialize_tun(); |
| loop(); |
| exit(1); |
| } |
| |
| static int inject_fault(int nth) |
| { |
| int fd; |
| char buf[16]; |
| fd = open("/proc/thread-self/fail-nth", O_RDWR); |
| if (fd == -1) |
| exit(1); |
| sprintf(buf, "%d", nth + 1); |
| if (write(fd, buf, strlen(buf)) != (ssize_t)strlen(buf)) |
| exit(1); |
| return fd; |
| } |
| |
| uint64_t r[1] = {0xffffffffffffffff}; |
| |
| void loop(void) |
| { |
| long res = 0; |
| memcpy((void*)0x20000100, "/dev/ptmx\x00", 10); |
| res = syscall(__NR_openat, 0xffffffffffffff9c, 0x20000100, 0, 0); |
| if (res != -1) |
| r[0] = res; |
| *(uint32_t*)0x200000c0 = 0xf; |
| syscall(__NR_ioctl, r[0], 0x5423, 0x200000c0); |
| write_file("/sys/kernel/debug/failslab/ignore-gfp-wait", "N"); |
| write_file("/sys/kernel/debug/fail_futex/ignore-private", "N"); |
| inject_fault(3); |
| syscall(__NR_ioctl, r[0], 0x400455c8, 2); |
| } |
| int main(void) |
| { |
| syscall(__NR_mmap, 0x20000000, 0x1000000, 3, 0x32, -1, 0); |
| do_sandbox_none(); |
| return 0; |
| } |