| // KASAN: slab-out-of-bounds Read in perf_event_fd_array_release |
| // https://syzkaller.appspot.com/bug?id=108823846938d216a90efa32a1ca5c7bdb08d029 |
| // status:fixed |
| // autogenerated by syzkaller (http://github.com/google/syzkaller) |
| |
| #define _GNU_SOURCE |
| #include <endian.h> |
| #include <errno.h> |
| #include <fcntl.h> |
| #include <linux/capability.h> |
| #include <sched.h> |
| #include <signal.h> |
| #include <stdarg.h> |
| #include <stdbool.h> |
| #include <stdio.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/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 <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 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 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); |
| |
| #define CLONE_NEWCGROUP 0x02000000 |
| |
| unshare(CLONE_NEWNS); |
| unshare(CLONE_NEWIPC); |
| unshare(CLONE_NEWCGROUP); |
| unshare(CLONE_NEWNET); |
| unshare(CLONE_NEWUTS); |
| unshare(CLONE_SYSVSEM); |
| } |
| |
| 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) |
| { |
| int pid; |
| |
| 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, NULL); |
| if (pid < 0) |
| fail("sandbox clone failed"); |
| return pid; |
| } |
| |
| #ifndef __NR_bpf |
| #define __NR_bpf 321 |
| #endif |
| |
| void loop() |
| { |
| syscall(__NR_mmap, 0x20000000, 0xfff000, 3, 0x32, -1, 0); |
| *(uint32_t*)0x20000000 = 4; |
| *(uint32_t*)0x20000004 = 4; |
| *(uint32_t*)0x20000008 = 4; |
| *(uint32_t*)0x2000000c = 0xfffffffc; |
| *(uint32_t*)0x20000010 = 0; |
| *(uint32_t*)0x20000014 = 0; |
| *(uint32_t*)0x20000018 = 0; |
| *(uint8_t*)0x2000001c = 0; |
| *(uint8_t*)0x2000001d = 0; |
| *(uint8_t*)0x2000001e = 0; |
| *(uint8_t*)0x2000001f = 0; |
| *(uint8_t*)0x20000020 = 0; |
| *(uint8_t*)0x20000021 = 0; |
| *(uint8_t*)0x20000022 = 0; |
| *(uint8_t*)0x20000023 = 0; |
| *(uint8_t*)0x20000024 = 0; |
| *(uint8_t*)0x20000025 = 0; |
| *(uint8_t*)0x20000026 = 0; |
| *(uint8_t*)0x20000027 = 0; |
| *(uint8_t*)0x20000028 = 0; |
| *(uint8_t*)0x20000029 = 0; |
| *(uint8_t*)0x2000002a = 0; |
| *(uint8_t*)0x2000002b = 0; |
| syscall(__NR_bpf, 0, 0x20000000, 0x2c); |
| } |
| |
| int main() |
| { |
| use_temporary_dir(); |
| int pid = do_sandbox_namespace(0, false); |
| int status = 0; |
| while (waitpid(pid, &status, __WALL) != pid) { |
| } |
| return 0; |
| } |