| // INFO: rcu detected stall in vprintk_emit |
| // https://syzkaller.appspot.com/bug?id=4a131cc571c3733e0eff6bc673f4e36ae48f19c6 |
| // status:fixed |
| // autogenerated by syzkaller (http://github.com/google/syzkaller) |
| |
| #define _GNU_SOURCE |
| #include <arpa/inet.h> |
| #include <endian.h> |
| #include <errno.h> |
| #include <fcntl.h> |
| #include <linux/if.h> |
| #include <linux/if_ether.h> |
| #include <linux/if_tun.h> |
| #include <linux/ip.h> |
| #include <linux/tcp.h> |
| #include <net/if_arp.h> |
| #include <sched.h> |
| #include <signal.h> |
| #include <stdarg.h> |
| #include <stdbool.h> |
| #include <stdio.h> |
| #include <stdlib.h> |
| #include <sys/ioctl.h> |
| #include <sys/prctl.h> |
| #include <sys/resource.h> |
| #include <sys/stat.h> |
| #include <sys/syscall.h> |
| #include <sys/time.h> |
| #include <sys/types.h> |
| #include <sys/uio.h> |
| #include <sys/wait.h> |
| #include <unistd.h> |
| |
| __attribute__((noreturn)) static void doexit(int status) |
| { |
| volatile unsigned i; |
| syscall(__NR_exit_group, status); |
| for (i = 0;; i++) { |
| } |
| } |
| #include <errno.h> |
| #include <setjmp.h> |
| #include <signal.h> |
| #include <stdarg.h> |
| #include <stdint.h> |
| #include <stdio.h> |
| #include <stdlib.h> |
| #include <string.h> |
| #include <sys/stat.h> |
| |
| const int kFailStatus = 67; |
| const int kRetryStatus = 69; |
| |
| static void fail(const char* msg, ...) |
| { |
| int e = errno; |
| va_list args; |
| va_start(args, msg); |
| vfprintf(stderr, msg, args); |
| va_end(args); |
| fprintf(stderr, " (errno %d)\n", e); |
| doexit((e == ENOMEM || e == EAGAIN) ? kRetryStatus : kFailStatus); |
| } |
| |
| static __thread int skip_segv; |
| static __thread jmp_buf segv_env; |
| |
| static void segv_handler(int sig, siginfo_t* info, void* uctx) |
| { |
| uintptr_t addr = (uintptr_t)info->si_addr; |
| const uintptr_t prog_start = 1 << 20; |
| const uintptr_t prog_end = 100 << 20; |
| if (__atomic_load_n(&skip_segv, __ATOMIC_RELAXED) && |
| (addr < prog_start || addr > prog_end)) { |
| _longjmp(segv_env, 1); |
| } |
| doexit(sig); |
| } |
| |
| static void install_segv_handler() |
| { |
| 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(...) \ |
| { \ |
| __atomic_fetch_add(&skip_segv, 1, __ATOMIC_SEQ_CST); \ |
| if (_setjmp(segv_env) == 0) { \ |
| __VA_ARGS__; \ |
| } \ |
| __atomic_fetch_sub(&skip_segv, 1, __ATOMIC_SEQ_CST); \ |
| } |
| |
| static void use_temporary_dir() |
| { |
| char tmpdir_template[] = "./syzkaller.XXXXXX"; |
| char* tmpdir = mkdtemp(tmpdir_template); |
| if (!tmpdir) |
| fail("failed to mkdtemp"); |
| if (chmod(tmpdir, 0777)) |
| fail("failed to chmod"); |
| if (chdir(tmpdir)) |
| fail("failed to chdir"); |
| } |
| |
| static void vsnprintf_check(char* str, size_t size, const char* format, |
| va_list args) |
| { |
| int rv; |
| |
| rv = vsnprintf(str, size, format, args); |
| if (rv < 0) |
| fail("tun: snprintf failed"); |
| if ((size_t)rv >= size) |
| fail("tun: string '%s...' doesn't fit into buffer", str); |
| } |
| |
| #define COMMAND_MAX_LEN 128 |
| #define PATH_PREFIX \ |
| "PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin " |
| #define PATH_PREFIX_LEN (sizeof(PATH_PREFIX) - 1) |
| |
| static void execute_command(bool panic, const char* format, ...) |
| { |
| va_list args; |
| char command[PATH_PREFIX_LEN + COMMAND_MAX_LEN]; |
| int rv; |
| |
| va_start(args, format); |
| memcpy(command, PATH_PREFIX, PATH_PREFIX_LEN); |
| vsnprintf_check(command + PATH_PREFIX_LEN, COMMAND_MAX_LEN, format, args); |
| va_end(args); |
| rv = system(command); |
| if (rv) { |
| if (panic) |
| fail("command '%s' failed: %d", &command[0], rv); |
| } |
| } |
| |
| static int tunfd = -1; |
| static int tun_frags_enabled; |
| |
| #define SYZ_TUN_MAX_PACKET_SIZE 1000 |
| |
| #define TUN_IFACE "syz_tun" |
| |
| #define LOCAL_MAC "aa:aa:aa:aa:aa:aa" |
| #define REMOTE_MAC "aa:aa:aa:aa:aa:bb" |
| |
| #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 = 252; |
| if (dup2(tunfd, kTunFd) < 0) |
| fail("dup2(tunfd, kTunFd) failed"); |
| 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) |
| fail("tun: ioctl(TUNSETIFF) failed"); |
| } |
| if (ioctl(tunfd, TUNGETIFF, (void*)&ifr) < 0) |
| fail("tun: ioctl(TUNGETIFF) failed"); |
| tun_frags_enabled = (ifr.ifr_flags & IFF_NAPI_FRAGS) != 0; |
| |
| execute_command(1, "sysctl -w net.ipv6.conf.%s.accept_dad=0", TUN_IFACE); |
| |
| execute_command(1, "sysctl -w net.ipv6.conf.%s.router_solicitations=0", |
| TUN_IFACE); |
| |
| execute_command(1, "ip link set dev %s address %s", TUN_IFACE, LOCAL_MAC); |
| execute_command(1, "ip addr add %s/24 dev %s", LOCAL_IPV4, TUN_IFACE); |
| execute_command(1, "ip -6 addr add %s/120 dev %s", LOCAL_IPV6, TUN_IFACE); |
| execute_command(1, "ip neigh add %s lladdr %s dev %s nud permanent", |
| REMOTE_IPV4, REMOTE_MAC, TUN_IFACE); |
| execute_command(1, "ip -6 neigh add %s lladdr %s dev %s nud permanent", |
| REMOTE_IPV6, REMOTE_MAC, TUN_IFACE); |
| execute_command(1, "ip link set dev %s up", TUN_IFACE); |
| } |
| |
| #define DEV_IPV4 "172.20.20.%d" |
| #define DEV_IPV6 "fe80::%02hx" |
| #define DEV_MAC "aa:aa:aa:aa:aa:%02hx" |
| |
| static void snprintf_check(char* str, size_t size, const char* format, ...) |
| { |
| va_list args; |
| |
| va_start(args, format); |
| vsnprintf_check(str, size, format, args); |
| va_end(args); |
| } |
| |
| static void initialize_netdevices(void) |
| { |
| unsigned i; |
| const char* devtypes[] = {"ip6gretap", "bridge", "vcan", "bond", "team"}; |
| const char* devnames[] = {"lo", |
| "sit0", |
| "bridge0", |
| "vcan0", |
| "tunl0", |
| "gre0", |
| "gretap0", |
| "ip_vti0", |
| "ip6_vti0", |
| "ip6tnl0", |
| "ip6gre0", |
| "ip6gretap0", |
| "erspan0", |
| "bond0", |
| "veth0", |
| "veth1", |
| "team0", |
| "veth0_to_bridge", |
| "veth1_to_bridge", |
| "veth0_to_bond", |
| "veth1_to_bond", |
| "veth0_to_team", |
| "veth1_to_team"}; |
| const char* devmasters[] = {"bridge", "bond", "team"}; |
| |
| for (i = 0; i < sizeof(devtypes) / (sizeof(devtypes[0])); i++) |
| execute_command(0, "ip link add dev %s0 type %s", devtypes[i], devtypes[i]); |
| execute_command(0, "ip link add type veth"); |
| |
| for (i = 0; i < sizeof(devmasters) / (sizeof(devmasters[0])); i++) { |
| execute_command( |
| 0, "ip link add name %s_slave_0 type veth peer name veth0_to_%s", |
| devmasters[i], devmasters[i]); |
| execute_command( |
| 0, "ip link add name %s_slave_1 type veth peer name veth1_to_%s", |
| devmasters[i], devmasters[i]); |
| execute_command(0, "ip link set %s_slave_0 master %s0", devmasters[i], |
| devmasters[i]); |
| execute_command(0, "ip link set %s_slave_1 master %s0", devmasters[i], |
| devmasters[i]); |
| execute_command(0, "ip link set veth0_to_%s up", devmasters[i]); |
| execute_command(0, "ip link set veth1_to_%s up", devmasters[i]); |
| } |
| execute_command(0, "ip link set bridge_slave_0 up"); |
| execute_command(0, "ip link set bridge_slave_1 up"); |
| |
| for (i = 0; i < sizeof(devnames) / (sizeof(devnames[0])); i++) { |
| char addr[32]; |
| snprintf_check(addr, sizeof(addr), DEV_IPV4, i + 10); |
| execute_command(0, "ip -4 addr add %s/24 dev %s", addr, devnames[i]); |
| snprintf_check(addr, sizeof(addr), DEV_IPV6, i + 10); |
| execute_command(0, "ip -6 addr add %s/120 dev %s", addr, devnames[i]); |
| snprintf_check(addr, sizeof(addr), DEV_MAC, i + 10); |
| execute_command(0, "ip link set dev %s address %s", devnames[i], addr); |
| execute_command(0, "ip link set dev %s up", devnames[i]); |
| } |
| } |
| |
| const int kInitNetNsFd = 253; |
| static uintptr_t syz_init_net_socket(uintptr_t domain, uintptr_t type, |
| uintptr_t proto) |
| { |
| int netns = open("/proc/self/ns/net", O_RDONLY); |
| if (netns == -1) |
| return netns; |
| if (setns(kInitNetNsFd, 0)) |
| return -1; |
| int sock = syscall(__NR_socket, domain, type, proto); |
| int err = errno; |
| if (setns(netns, 0)) |
| fail("setns(netns) failed"); |
| close(netns); |
| errno = err; |
| return sock; |
| } |
| |
| static void loop(); |
| |
| static void sandbox_common() |
| { |
| prctl(PR_SET_PDEATHSIG, SIGKILL, 0, 0, 0); |
| setpgrp(); |
| setsid(); |
| |
| int netns = open("/proc/self/ns/net", O_RDONLY); |
| if (netns == -1) |
| fail("open(/proc/self/ns/net) failed"); |
| if (dup2(netns, kInitNetNsFd) < 0) |
| fail("dup2(netns, kInitNetNsFd) failed"); |
| close(netns); |
| |
| struct rlimit rlim; |
| rlim.rlim_cur = rlim.rlim_max = 160 << 20; |
| setrlimit(RLIMIT_AS, &rlim); |
| rlim.rlim_cur = rlim.rlim_max = 8 << 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); |
| |
| if (unshare(CLONE_NEWNS)) { |
| } |
| if (unshare(CLONE_NEWIPC)) { |
| } |
| if (unshare(0x02000000)) { |
| } |
| if (unshare(CLONE_NEWUTS)) { |
| } |
| if (unshare(CLONE_SYSVSEM)) { |
| } |
| } |
| |
| static int do_sandbox_none(void) |
| { |
| if (unshare(CLONE_NEWPID)) { |
| } |
| int pid = fork(); |
| if (pid < 0) |
| fail("sandbox fork failed"); |
| if (pid) |
| return pid; |
| |
| sandbox_common(); |
| if (unshare(CLONE_NEWNET)) { |
| } |
| initialize_tun(); |
| initialize_netdevices(); |
| loop(); |
| doexit(1); |
| } |
| |
| uint64_t r[1] = {0xffffffffffffffff}; |
| void loop() |
| { |
| long res = 0; |
| NONFAILING(*(uint64_t*)0x20002500 = 0x200004c0); |
| NONFAILING(*(uint32_t*)0x20002508 = 0x80); |
| NONFAILING(*(uint64_t*)0x20002510 = 0x20000340); |
| NONFAILING(*(uint64_t*)0x20002518 = 0); |
| NONFAILING(*(uint64_t*)0x20002520 = 0x20000600); |
| NONFAILING(*(uint64_t*)0x20002528 = 0x1b); |
| NONFAILING(*(uint32_t*)0x20002530 = 0); |
| NONFAILING(*(uint32_t*)0x20002538 = 0); |
| NONFAILING(*(uint64_t*)0x20002540 = 0); |
| NONFAILING(*(uint32_t*)0x20002548 = 0); |
| NONFAILING(*(uint64_t*)0x20002550 = 0x20000840); |
| NONFAILING(*(uint64_t*)0x20002558 = 0); |
| NONFAILING(*(uint64_t*)0x20002560 = 0); |
| NONFAILING(*(uint64_t*)0x20002568 = 0); |
| NONFAILING(*(uint32_t*)0x20002570 = 0); |
| NONFAILING(*(uint32_t*)0x20002578 = 0); |
| NONFAILING(*(uint64_t*)0x20002580 = 0x200001c0); |
| NONFAILING(*(uint32_t*)0x20002588 = 0x80); |
| NONFAILING(*(uint64_t*)0x20002590 = 0x20001980); |
| NONFAILING(*(uint64_t*)0x20002598 = 0x252); |
| NONFAILING(*(uint64_t*)0x200025a0 = 0x200002c0); |
| NONFAILING(*(uint64_t*)0x200025a8 = 0x1c); |
| NONFAILING(*(uint32_t*)0x200025b0 = 0); |
| NONFAILING(*(uint32_t*)0x200025b8 = 0); |
| NONFAILING(*(uint64_t*)0x200025c0 = 0x20000040); |
| NONFAILING(*(uint32_t*)0x200025c8 = 0x80); |
| NONFAILING(*(uint64_t*)0x200025d0 = 0x20000240); |
| NONFAILING(*(uint64_t*)0x200025d8 = 0); |
| NONFAILING(*(uint64_t*)0x200025e0 = 0x20001a80); |
| NONFAILING(*(uint64_t*)0x200025e8 = 0x47); |
| NONFAILING(*(uint32_t*)0x200025f0 = 0); |
| NONFAILING(*(uint32_t*)0x200025f8 = 0); |
| NONFAILING(*(uint64_t*)0x20002600 = 0x20001d80); |
| NONFAILING(*(uint32_t*)0x20002608 = 0x80); |
| NONFAILING(*(uint64_t*)0x20002610 = 0x200023c0); |
| NONFAILING(*(uint64_t*)0x20002618 = 0); |
| NONFAILING(*(uint64_t*)0x20002620 = 0x20002480); |
| NONFAILING(*(uint64_t*)0x20002628 = 0x57); |
| NONFAILING(*(uint32_t*)0x20002630 = 0x800000); |
| NONFAILING(*(uint32_t*)0x20002638 = 0x200007); |
| NONFAILING(*(uint64_t*)0x20003740 = 0); |
| NONFAILING(*(uint64_t*)0x20003748 = 0); |
| syscall(__NR_recvmmsg, -1, 0x20002500, 5, 0, 0x20003740); |
| res = syz_init_net_socket(0x27, 2, 1); |
| if (res != -1) |
| r[0] = res; |
| NONFAILING(*(uint16_t*)0x20000140 = 0x27); |
| NONFAILING(*(uint32_t*)0x20000144 = 0); |
| NONFAILING(*(uint32_t*)0x20000148 = 0); |
| NONFAILING(*(uint32_t*)0x2000014c = 0); |
| NONFAILING(*(uint8_t*)0x20000150 = 0); |
| NONFAILING(*(uint8_t*)0x20000151 = 0); |
| NONFAILING( |
| memcpy((void*)0x20000152, |
| "\x6c\xb7\x82\xe4\xad\x88\xb8\x9d\x1f\xd3\x09\x16\x9f\x44\xa7\x21" |
| "\x07\x13\x0e\xe5\x5d\x66\x05\x10\x42\x0a\xaa\x96\x75\x9e\xcb\xc3" |
| "\x6e\xb9\xbb\x12\xb6\x12\x47\x93\x60\x8d\xd0\xe7\x31\x6d\x1d\x4f" |
| "\x4d\xba\xc3\x98\x77\xe4\xac\x71\x4b\x7e\xce\xfa\x8a\x93\x4a", |
| 63)); |
| NONFAILING(*(uint64_t*)0x20000198 = 0); |
| syscall(__NR_bind, r[0], 0x20000140, 0x60); |
| NONFAILING(*(uint64_t*)0x200026c0 = 0x200000c0); |
| NONFAILING(*(uint16_t*)0x200000c0 = 0x24); |
| NONFAILING(*(uint32_t*)0x200000c4 = 0); |
| NONFAILING(*(uint32_t*)0x200000c8 = 0); |
| NONFAILING(*(uint32_t*)0x200000cc = 0); |
| NONFAILING(*(uint8_t*)0x200000d0 = 0); |
| NONFAILING(*(uint8_t*)0x200000d1 = 0); |
| NONFAILING( |
| memcpy((void*)0x200000d2, |
| "\xc9\x5d\x9d\x47\xe4\x63\x5c\x99\x5b\x18\xba\x76\x6a\x81\x86\x48" |
| "\xcd\x01\xf2\xe3\x82\x5b\xee\x3e\xb3\x73\x76\x9c\xb2\xc8\x5d\x7f" |
| "\x0b\xb3\xaf\xf5\x8d\x31\xb0\x35\x28\x95\x60\x1e\xe2\x39\x88\x3a" |
| "\xbf\xad\x45\xa0\xe8\xc0\xf5\x9b\xf3\xb5\x2e\xdf\x35\x00\xbb", |
| 63)); |
| NONFAILING(*(uint64_t*)0x20000118 = 0); |
| NONFAILING(*(uint32_t*)0x200026c8 = 0x60); |
| NONFAILING(*(uint64_t*)0x200026d0 = 0x20002600); |
| NONFAILING(*(uint64_t*)0x200026d8 = 0x5f); |
| NONFAILING(*(uint64_t*)0x200026e0 = 0); |
| NONFAILING(*(uint64_t*)0x200026e8 = 0); |
| NONFAILING(*(uint32_t*)0x200026f0 = 0); |
| syscall(__NR_sendmmsg, r[0], 0x200026c0, 0x4924924924926b2, 0); |
| } |
| |
| int main() |
| { |
| syscall(__NR_mmap, 0x20000000, 0x1000000, 3, 0x32, -1, 0); |
| install_segv_handler(); |
| use_temporary_dir(); |
| int pid = do_sandbox_none(); |
| int status = 0; |
| while (waitpid(pid, &status, __WALL) != pid) { |
| } |
| return 0; |
| } |
