| // kernel BUG at net/core/dev.c:LINE! |
| // https://syzkaller.appspot.com/bug?id=8ea2eae6ad496f121c662888440fc2469217e87a |
| // status:fixed |
| // autogenerated by syzkaller (http://github.com/google/syzkaller) |
| |
| #define _GNU_SOURCE |
| |
| #include <dirent.h> |
| #include <errno.h> |
| #include <errno.h> |
| #include <fcntl.h> |
| #include <fcntl.h> |
| #include <linux/capability.h> |
| #include <pthread.h> |
| #include <sched.h> |
| #include <signal.h> |
| #include <signal.h> |
| #include <stdarg.h> |
| #include <stdarg.h> |
| #include <stdbool.h> |
| #include <stdio.h> |
| #include <stdio.h> |
| #include <stdio.h> |
| #include <stdlib.h> |
| #include <sys/mman.h> |
| #include <sys/mount.h> |
| #include <sys/mount.h> |
| #include <sys/prctl.h> |
| #include <sys/prctl.h> |
| #include <sys/resource.h> |
| #include <sys/stat.h> |
| #include <sys/stat.h> |
| #include <sys/syscall.h> |
| #include <sys/time.h> |
| #include <sys/time.h> |
| #include <sys/wait.h> |
| #include <sys/wait.h> |
| #include <time.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 <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 void exitf(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(kRetryStatus); |
| } |
| |
| static uint64_t current_time_ms() |
| { |
| struct timespec ts; |
| |
| if (clock_gettime(CLOCK_MONOTONIC, &ts)) |
| fail("clock_gettime failed"); |
| return (uint64_t)ts.tv_sec * 1000 + (uint64_t)ts.tv_nsec / 1000000; |
| } |
| |
| 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 uintptr_t syz_open_dev(uintptr_t a0, uintptr_t a1, uintptr_t 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 { |
| char buf[1024]; |
| char* hash; |
| strncpy(buf, (char*)a0, sizeof(buf)); |
| buf[sizeof(buf) - 1] = 0; |
| while ((hash = strchr(buf, '#'))) { |
| *hash = '0' + (char)(a1 % 10); |
| a1 /= 10; |
| } |
| return open(buf, a2, 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 = 128 << 20; |
| setrlimit(RLIMIT_AS, &rlim); |
| rlim.rlim_cur = rlim.rlim_max = 8 << 20; |
| setrlimit(RLIMIT_MEMLOCK, &rlim); |
| rlim.rlim_cur = rlim.rlim_max = 1 << 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); |
| |
| unshare(CLONE_NEWNS); |
| unshare(CLONE_NEWIPC); |
| unshare(CLONE_IO); |
| } |
| |
| 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) { |
| close(fd); |
| return false; |
| } |
| close(fd); |
| return true; |
| } |
| |
| 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)) |
| fail("write of /proc/self/uid_map failed"); |
| if (!write_file("/proc/self/gid_map", "0 %d 1\n", real_gid)) |
| fail("write of /proc/self/gid_map failed"); |
| |
| if (mkdir("./syz-tmp", 0777)) |
| fail("mkdir(syz-tmp) failed"); |
| if (mount("", "./syz-tmp", "tmpfs", 0, NULL)) |
| fail("mount(tmpfs) failed"); |
| if (mkdir("./syz-tmp/newroot", 0777)) |
| fail("mkdir failed"); |
| if (mkdir("./syz-tmp/newroot/dev", 0700)) |
| fail("mkdir failed"); |
| if (mount("/dev", "./syz-tmp/newroot/dev", NULL, |
| MS_BIND | MS_REC | MS_PRIVATE, NULL)) |
| fail("mount(dev) failed"); |
| if (mkdir("./syz-tmp/newroot/proc", 0700)) |
| fail("mkdir failed"); |
| if (mount(NULL, "./syz-tmp/newroot/proc", "proc", 0, NULL)) |
| fail("mount(proc) failed"); |
| if (mkdir("./syz-tmp/pivot", 0777)) |
| fail("mkdir failed"); |
| if (syscall(SYS_pivot_root, "./syz-tmp", "./syz-tmp/pivot")) { |
| if (chdir("./syz-tmp")) |
| fail("chdir failed"); |
| } else { |
| if (chdir("/")) |
| fail("chdir failed"); |
| if (umount2("./pivot", MNT_DETACH)) |
| fail("umount failed"); |
| } |
| if (chroot("./newroot")) |
| fail("chroot failed"); |
| if (chdir("/")) |
| fail("chdir failed"); |
| |
| 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)) |
| fail("capget failed"); |
| cap_data[0].effective &= ~(1 << CAP_SYS_PTRACE); |
| cap_data[0].permitted &= ~(1 << CAP_SYS_PTRACE); |
| cap_data[0].inheritable &= ~(1 << CAP_SYS_PTRACE); |
| if (syscall(SYS_capset, &cap_hdr, &cap_data)) |
| fail("capset failed"); |
| |
| loop(); |
| doexit(1); |
| } |
| |
| static int do_sandbox_namespace(int executor_pid, bool enable_tun) |
| { |
| |
| real_uid = getuid(); |
| real_gid = getgid(); |
| mprotect(sandbox_stack, 4096, PROT_NONE); |
| return clone( |
| namespace_sandbox_proc, |
| &sandbox_stack[sizeof(sandbox_stack) - 64], |
| CLONE_NEWUSER | CLONE_NEWPID | CLONE_NEWUTS | CLONE_NEWNET, NULL); |
| } |
| |
| static void remove_dir(const char* dir) |
| { |
| DIR* dp; |
| struct dirent* ep; |
| int iter = 0; |
| retry: |
| dp = opendir(dir); |
| if (dp == NULL) { |
| if (errno == EMFILE) { |
| exitf("opendir(%s) failed due to NOFILE, exiting"); |
| } |
| exitf("opendir(%s) failed", dir); |
| } |
| 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); |
| struct stat st; |
| if (lstat(filename, &st)) |
| exitf("lstat(%s) failed", filename); |
| if (S_ISDIR(st.st_mode)) { |
| remove_dir(filename); |
| continue; |
| } |
| int i; |
| for (i = 0;; i++) { |
| if (unlink(filename) == 0) |
| break; |
| if (errno == EROFS) { |
| break; |
| } |
| if (errno != EBUSY || i > 100) |
| exitf("unlink(%s) failed", filename); |
| if (umount2(filename, MNT_DETACH)) |
| exitf("umount(%s) failed", filename); |
| } |
| } |
| closedir(dp); |
| int i; |
| for (i = 0;; i++) { |
| if (rmdir(dir) == 0) |
| break; |
| if (i < 100) { |
| if (errno == EROFS) { |
| break; |
| } |
| if (errno == EBUSY) { |
| if (umount2(dir, MNT_DETACH)) |
| exitf("umount(%s) failed", dir); |
| continue; |
| } |
| if (errno == ENOTEMPTY) { |
| if (iter < 100) { |
| iter++; |
| goto retry; |
| } |
| } |
| } |
| exitf("rmdir(%s) failed", dir); |
| } |
| } |
| |
| static void test(); |
| |
| void loop() |
| { |
| int iter; |
| for (iter = 0;; iter++) { |
| char cwdbuf[256]; |
| sprintf(cwdbuf, "./%d", iter); |
| if (mkdir(cwdbuf, 0777)) |
| fail("failed to mkdir"); |
| int pid = fork(); |
| if (pid < 0) |
| fail("clone failed"); |
| if (pid == 0) { |
| prctl(PR_SET_PDEATHSIG, SIGKILL, 0, 0, 0); |
| setpgrp(); |
| if (chdir(cwdbuf)) |
| fail("failed to chdir"); |
| test(); |
| doexit(0); |
| } |
| int status = 0; |
| uint64_t start = current_time_ms(); |
| for (;;) { |
| int res = waitpid(-1, &status, __WALL | WNOHANG); |
| if (res == pid) |
| break; |
| usleep(1000); |
| if (current_time_ms() - start > 5 * 1000) { |
| kill(-pid, SIGKILL); |
| kill(pid, SIGKILL); |
| while (waitpid(-1, &status, __WALL) != pid) { |
| } |
| break; |
| } |
| } |
| remove_dir(cwdbuf); |
| } |
| } |
| |
| long r[82]; |
| void* thr(void* arg) |
| { |
| switch ((long)arg) { |
| case 0: |
| r[0] = syscall(__NR_mmap, 0x20000000ul, 0xfff000ul, 0x3ul, 0x32ul, |
| 0xfffffffffffffffful, 0x0ul); |
| break; |
| case 1: |
| r[1] = syscall(__NR_socket, 0x2ul, 0x1ul, 0x0ul); |
| break; |
| case 2: |
| memcpy((void*)0x20c55000, |
| "\x2f\x64\x65\x76\x2f\x6e\x65\x74\x2f\x74\x75\x6e\x00", 13); |
| r[3] = syz_open_dev(0x20c55000ul, 0x0ul, 0x100000aul); |
| break; |
| case 3: |
| r[4] = syscall(__NR_socket, 0x2000000011ul, 0x3ul, 0x0ul); |
| break; |
| case 4: |
| *(uint8_t*)0x20927fd8 = (uint8_t)0x73; |
| *(uint8_t*)0x20927fd9 = (uint8_t)0x79; |
| *(uint8_t*)0x20927fda = (uint8_t)0x7a; |
| *(uint8_t*)0x20927fdb = (uint8_t)0x30; |
| *(uint8_t*)0x20927fdc = (uint8_t)0x0; |
| *(uint32_t*)0x20927fe8 = (uint32_t)0x5; |
| *(uint32_t*)0x20927fec = (uint32_t)0x0; |
| *(uint64_t*)0x20927ff0 = (uint64_t)0x201a3ff4; |
| *(uint32_t*)0x201a3ff4 = (uint32_t)0x0; |
| *(uint32_t*)0x201a3ff8 = (uint32_t)0x0; |
| *(uint16_t*)0x201a3ffc = (uint16_t)0x0; |
| r[16] = syscall(__NR_ioctl, r[3], 0x400454caul, 0x20927fd8ul); |
| break; |
| case 5: |
| *(uint8_t*)0x2062ffe0 = (uint8_t)0x73; |
| *(uint8_t*)0x2062ffe1 = (uint8_t)0x79; |
| *(uint8_t*)0x2062ffe2 = (uint8_t)0x7a; |
| *(uint8_t*)0x2062ffe3 = (uint8_t)0x30; |
| *(uint8_t*)0x2062ffe4 = (uint8_t)0x0; |
| *(uint16_t*)0x2062fff0 = (uint16_t)0x20301; |
| r[23] = syscall(__NR_ioctl, r[1], 0x8914ul, 0x2062ffe0ul); |
| break; |
| case 6: |
| *(uint8_t*)0x20b13000 = (uint8_t)0x73; |
| *(uint8_t*)0x20b13001 = (uint8_t)0x79; |
| *(uint8_t*)0x20b13002 = (uint8_t)0x7a; |
| *(uint8_t*)0x20b13003 = (uint8_t)0x30; |
| *(uint8_t*)0x20b13004 = (uint8_t)0x0; |
| *(uint32_t*)0x20b13010 = (uint32_t)0x0; |
| *(uint8_t*)0x20b13014 = (uint8_t)0x0; |
| *(uint8_t*)0x20b13015 = (uint8_t)0x0; |
| *(uint8_t*)0x20b13016 = (uint8_t)0x0; |
| *(uint8_t*)0x20b13017 = (uint8_t)0x0; |
| *(uint8_t*)0x20b13018 = (uint8_t)0x0; |
| *(uint8_t*)0x20b13019 = (uint8_t)0x0; |
| *(uint8_t*)0x20b1301a = (uint8_t)0x0; |
| *(uint8_t*)0x20b1301b = (uint8_t)0x0; |
| *(uint8_t*)0x20b1301c = (uint8_t)0x0; |
| *(uint8_t*)0x20b1301d = (uint8_t)0x0; |
| *(uint8_t*)0x20b1301e = (uint8_t)0x0; |
| *(uint8_t*)0x20b1301f = (uint8_t)0x0; |
| *(uint8_t*)0x20b13020 = (uint8_t)0x0; |
| *(uint8_t*)0x20b13021 = (uint8_t)0x0; |
| *(uint8_t*)0x20b13022 = (uint8_t)0x0; |
| *(uint8_t*)0x20b13023 = (uint8_t)0x0; |
| *(uint8_t*)0x20b13024 = (uint8_t)0x0; |
| *(uint8_t*)0x20b13025 = (uint8_t)0x0; |
| *(uint8_t*)0x20b13026 = (uint8_t)0x0; |
| *(uint8_t*)0x20b13027 = (uint8_t)0x0; |
| r[50] = syscall(__NR_ioctl, r[4], 0x8933ul, 0x20b13000ul); |
| if (r[50] != -1) |
| r[51] = *(uint32_t*)0x20b13010; |
| break; |
| case 7: |
| *(uint16_t*)0x20c85000 = (uint16_t)0x11; |
| *(uint16_t*)0x20c85002 = (uint16_t)0x300; |
| *(uint32_t*)0x20c85004 = r[51]; |
| *(uint16_t*)0x20c85008 = (uint16_t)0x1; |
| *(uint8_t*)0x20c8500a = (uint8_t)0x0; |
| *(uint8_t*)0x20c8500b = (uint8_t)0x6; |
| *(uint8_t*)0x20c8500c = (uint8_t)0xbb; |
| *(uint8_t*)0x20c8500d = (uint8_t)0xbb; |
| *(uint8_t*)0x20c8500e = (uint8_t)0xbb; |
| *(uint8_t*)0x20c8500f = (uint8_t)0xbb; |
| *(uint8_t*)0x20c85010 = (uint8_t)0xbb; |
| *(uint8_t*)0x20c85011 = (uint8_t)0x0; |
| *(uint8_t*)0x20c85012 = (uint8_t)0x0; |
| *(uint8_t*)0x20c85013 = (uint8_t)0x0; |
| r[66] = syscall(__NR_bind, r[4], 0x20c85000ul, 0x14ul); |
| break; |
| case 8: |
| *(uint16_t*)0x20041000 = (uint16_t)0x11; |
| *(uint16_t*)0x20041002 = (uint16_t)0x1700; |
| *(uint32_t*)0x20041004 = r[51]; |
| *(uint16_t*)0x20041008 = (uint16_t)0x1; |
| *(uint8_t*)0x2004100a = (uint8_t)0x7; |
| *(uint8_t*)0x2004100b = (uint8_t)0x6; |
| *(uint8_t*)0x2004100c = (uint8_t)0x0; |
| *(uint8_t*)0x2004100d = (uint8_t)0x0; |
| *(uint8_t*)0x2004100e = (uint8_t)0x0; |
| *(uint8_t*)0x2004100f = (uint8_t)0x0; |
| *(uint8_t*)0x20041010 = (uint8_t)0x0; |
| *(uint8_t*)0x20041011 = (uint8_t)0x0; |
| *(uint8_t*)0x20041012 = (uint8_t)0x0; |
| *(uint8_t*)0x20041013 = (uint8_t)0x0; |
| r[81] = syscall(__NR_bind, r[4], 0x20041000ul, 0x14ul); |
| break; |
| } |
| return 0; |
| } |
| |
| void test() |
| { |
| long i; |
| pthread_t th[18]; |
| |
| memset(r, -1, sizeof(r)); |
| for (i = 0; i < 9; i++) { |
| pthread_create(&th[i], 0, thr, (void*)i); |
| usleep(rand() % 10000); |
| } |
| usleep(rand() % 100000); |
| } |
| |
| int main() |
| { |
| int i; |
| for (i = 0; i < 8; i++) { |
| if (fork() == 0) { |
| use_temporary_dir(); |
| int pid = do_sandbox_namespace(i, false); |
| int status = 0; |
| while (waitpid(pid, &status, __WALL) != pid) { |
| } |
| return 0; |
| } |
| } |
| sleep(1000000); |
| return 0; |
| } |