| // KMSAN: kernel-infoleak in copy_siginfo_to_user (2) |
| // https://syzkaller.appspot.com/bug?id=28e7ff641990195658d27ff5911eb34d10a5bda0 |
| // status:fixed |
| // autogenerated by syzkaller (https://github.com/google/syzkaller) |
| |
| #define _GNU_SOURCE |
| |
| #include <dirent.h> |
| #include <endian.h> |
| #include <errno.h> |
| #include <fcntl.h> |
| #include <sched.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/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> |
| |
| 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; |
| } |
| |
| 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 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); |
| 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(NULL, "./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 (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); |
| 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); |
| 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)) |
| exit(1); |
| loop(); |
| exit(1); |
| } |
| |
| #define SYZ_HAVE_SANDBOX_NAMESPACE 1 |
| static int do_sandbox_namespace(void) |
| { |
| int pid; |
| setup_common(); |
| real_uid = getuid(); |
| real_gid = getgid(); |
| mprotect(sandbox_stack, 4096, PROT_NONE); |
| 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) |
| { |
| DIR* dp; |
| struct dirent* ep; |
| int iter = 0; |
| retry: |
| while (umount2(dir, MNT_DETACH) == 0) { |
| } |
| dp = opendir(dir); |
| if (dp == NULL) { |
| if (errno == EMFILE) { |
| exit(1); |
| } |
| exit(1); |
| } |
| 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, MNT_DETACH) == 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, MNT_DETACH)) |
| exit(1); |
| } |
| } |
| closedir(dp); |
| int i; |
| for (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, MNT_DETACH)) |
| 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); |
| int i; |
| for (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) { |
| } |
| } |
| |
| #define SYZ_HAVE_SETUP_TEST 1 |
| static void setup_test() |
| { |
| prctl(PR_SET_PDEATHSIG, SIGKILL, 0, 0, 0); |
| setpgrp(); |
| write_file("/proc/self/oom_score_adj", "1000"); |
| } |
| |
| #define SYZ_HAVE_CLOSE_FDS 1 |
| static void close_fds() |
| { |
| int fd; |
| for (fd = 3; fd < 30; fd++) |
| close(fd); |
| } |
| |
| static void execute_one(void); |
| |
| #define WAIT_FLAGS __WALL |
| |
| static void loop(void) |
| { |
| int iter; |
| for (iter = 0;; 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(); |
| close_fds(); |
| exit(0); |
| } |
| int status = 0; |
| uint64_t start = current_time_ms(); |
| for (;;) { |
| if (waitpid(-1, &status, WNOHANG | WAIT_FLAGS) == pid) |
| break; |
| sleep_ms(1); |
| if (current_time_ms() - start < 5 * 1000) |
| continue; |
| kill_and_wait(pid, &status); |
| break; |
| } |
| remove_dir(cwdbuf); |
| } |
| } |
| |
| uint64_t r[1] = {0x0}; |
| |
| void execute_one(void) |
| { |
| long res = 0; |
| *(uint16_t*)0x200000c0 = 0; |
| *(uint16_t*)0x200000c2 = 0xfffe; |
| *(uint64_t*)0x200000c8 = 0x4100000000; |
| *(uint64_t*)0x200000d0 = 0; |
| *(uint32_t*)0x200000d8 = 0; |
| *(uint32_t*)0x200000dc = 0; |
| *(uint32_t*)0x200000e0 = 0; |
| *(uint32_t*)0x200000e4 = 0; |
| *(uint32_t*)0x200000e8 = 0; |
| *(uint32_t*)0x200000ec = 0; |
| syscall(__NR_ioctl, -1, 0x40305828, 0x200000c0); |
| syscall(__NR_clone, 0x2102001fff, 0, 0x9999999999999999, 0, -1); |
| res = syscall(__NR_getpid); |
| if (res != -1) |
| r[0] = res; |
| *(uint32_t*)0x20000180 = 0; |
| *(uint32_t*)0x20000184 = 0; |
| *(uint32_t*)0x20000188 = 0; |
| syscall(__NR_rt_tgsigqueueinfo, r[0], r[0], 0x16, 0x20000180); |
| syscall(__NR_ptrace, 0x10, r[0], 0, 0); |
| syscall(__NR_ptrace, 0x4209, r[0], 0x200000c0, 0x716000); |
| } |
| int main(void) |
| { |
| syscall(__NR_mmap, 0x20000000, 0x1000000, 3, 0x32, -1, 0); |
| for (procid = 0; procid < 6; procid++) { |
| if (fork() == 0) { |
| use_temporary_dir(); |
| do_sandbox_namespace(); |
| } |
| } |
| sleep(1000000); |
| return 0; |
| } |