// https://syzkaller.appspot.com/bug?id=7ad88f69a3bdc2aa316189b85ea1c6da6f108c12 // autogenerated by syzkaller (https://github.com/google/syzkaller) #define _GNU_SOURCE #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include static unsigned long long procid; 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; } struct fs_image_segment { void* data; uintptr_t size; uintptr_t offset; }; #define IMAGE_MAX_SEGMENTS 4096 #define IMAGE_MAX_SIZE (129 << 20) #define sys_memfd_create 319 static unsigned long fs_image_segment_check(unsigned long size, unsigned long nsegs, struct fs_image_segment* segs) { if (nsegs > IMAGE_MAX_SEGMENTS) nsegs = IMAGE_MAX_SEGMENTS; for (size_t i = 0; i < nsegs; i++) { if (segs[i].size > IMAGE_MAX_SIZE) segs[i].size = IMAGE_MAX_SIZE; segs[i].offset %= IMAGE_MAX_SIZE; if (segs[i].offset > IMAGE_MAX_SIZE - segs[i].size) segs[i].offset = IMAGE_MAX_SIZE - segs[i].size; if (size < segs[i].offset + segs[i].offset) size = segs[i].offset + segs[i].offset; } if (size > IMAGE_MAX_SIZE) size = IMAGE_MAX_SIZE; return size; } static int setup_loop_device(long unsigned size, long unsigned nsegs, struct fs_image_segment* segs, const char* loopname, int* memfd_p, int* loopfd_p) { int err = 0, loopfd = -1; size = fs_image_segment_check(size, nsegs, segs); int memfd = syscall(sys_memfd_create, "syzkaller", 0); if (memfd == -1) { err = errno; goto error; } if (ftruncate(memfd, size)) { err = errno; goto error_close_memfd; } for (size_t i = 0; i < nsegs; i++) { if (pwrite(memfd, segs[i].data, segs[i].size, segs[i].offset) < 0) { } } loopfd = open(loopname, O_RDWR); if (loopfd == -1) { err = errno; goto error_close_memfd; } if (ioctl(loopfd, LOOP_SET_FD, memfd)) { if (errno != EBUSY) { err = errno; goto error_close_loop; } ioctl(loopfd, LOOP_CLR_FD, 0); usleep(1000); if (ioctl(loopfd, LOOP_SET_FD, memfd)) { err = errno; goto error_close_loop; } } *memfd_p = memfd; *loopfd_p = loopfd; return 0; error_close_loop: close(loopfd); error_close_memfd: close(memfd); error: errno = err; return -1; } static long syz_mount_image(volatile long fsarg, volatile long dir, volatile unsigned long size, volatile unsigned long nsegs, volatile long segments, volatile long flags, volatile long optsarg) { struct fs_image_segment* segs = (struct fs_image_segment*)segments; int res = -1, err = 0, loopfd = -1, memfd = -1, need_loop_device = !!segs; char* mount_opts = (char*)optsarg; char* target = (char*)dir; char* fs = (char*)fsarg; char* source = NULL; char loopname[64]; if (need_loop_device) { memset(loopname, 0, sizeof(loopname)); snprintf(loopname, sizeof(loopname), "/dev/loop%llu", procid); if (setup_loop_device(size, nsegs, segs, loopname, &memfd, &loopfd) == -1) return -1; source = loopname; } mkdir(target, 0777); char opts[256]; memset(opts, 0, sizeof(opts)); if (strlen(mount_opts) > (sizeof(opts) - 32)) { } strncpy(opts, mount_opts, sizeof(opts) - 32); if (strcmp(fs, "iso9660") == 0) { flags |= MS_RDONLY; } else if (strncmp(fs, "ext", 3) == 0) { if (strstr(opts, "errors=panic") || strstr(opts, "errors=remount-ro") == 0) strcat(opts, ",errors=continue"); } else if (strcmp(fs, "xfs") == 0) { strcat(opts, ",nouuid"); } res = mount(source, target, fs, flags, opts); if (res == -1) { err = errno; goto error_clear_loop; } res = open(target, O_RDONLY | O_DIRECTORY); if (res == -1) { err = errno; } error_clear_loop: if (need_loop_device) { ioctl(loopfd, LOOP_CLR_FD, 0); close(loopfd); close(memfd); } errno = err; return res; } 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 (mount(NULL, "/", NULL, MS_REC | MS_PRIVATE, NULL)) { } 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); } static int wait_for_loop(int pid) { if (pid < 0) exit(1); int status = 0; while (waitpid(-1, &status, __WALL) != pid) { } return WEXITSTATUS(status); } static void drop_caps(void) { 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); const int drop = (1 << CAP_SYS_PTRACE) | (1 << CAP_SYS_NICE); cap_data[0].effective &= ~drop; cap_data[0].permitted &= ~drop; cap_data[0].inheritable &= ~drop; if (syscall(SYS_capset, &cap_hdr, &cap_data)) exit(1); } 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(); drop_caps(); if (unshare(CLONE_NEWNET)) { } loop(); exit(1); } void loop(void) { memcpy((void*)0x20000000, "ntfs\000", 5); memcpy((void*)0x20000100, "./file0\000", 8); *(uint64_t*)0x20000200 = 0x20010000; memcpy((void*)0x20010000, "\xeb\x52\x90\x4e\x54\x46\x53\x20\x20\x20\x20\x00\x04\x04\x00\x00\x00" "\x00\x00\x00\x00\xf8\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00" "\x00\x00\x80\x00\x80\x00\xff\x07\x00\x00\x00\x00\x00\x00\x04\x00\x00" "\x00\x00\x00\x00\x00\xff\x00\x00\x00\x00\x00\x00\x00\xf6\x00\x00\x00" "\x01\x00\x00\x00\xa3\xb8\xb2\x0f\xcf\x7a\xa8\x36\x00\x00\x00\x00\x0e" "\x1f\xbe\x71\x7c\xac\x22\xc0\x74\x0b\x56\xb4\x0e\xbb\x07\x00\xcd\x10" "\x5e\xeb\xf0\x32\xe4\xcd\x16\xcd\x19\xeb\xfe\x54\x68\x69\x73\x20\x69" "\x73\x20\x6e\x6f\x74\x20\x61\x20\x62\x6f\x6f\x74\x61\x62\x6c\x65\x20" "\x64\x69\x73\x6b\x2e\x20\x50\x6c\x65\x61\x73\x65\x20\x69\x6e\x73\x65" "\x72\x74\x20\x61\x20\x62\x6f\x6f\x74\x61\x62\x6c\x65\x20\x66\x6c\x6f" "\x70\x70\x79\x20\x61\x6e\x64\x0d\x0a\x70\x72\x65\x73\x73\x20\x61\x6e" "\x79\x20\x6b\x65\x79\x20\x74\x6f\x20\x74\x72\x79\x20\x61\x67\x61\x69" "\x6e\x20\x2e\x2e\x2e\x20\x0d\x0a\x00\x00\x00\x00\x00\x00\x00\x00\x00" "\x00\x00\x00", 224); *(uint64_t*)0x20000208 = 0xe0; *(uint64_t*)0x20000210 = 0; *(uint64_t*)0x20000218 = 0; *(uint64_t*)0x20000220 = 0; *(uint64_t*)0x20000228 = 0x1e0; *(uint64_t*)0x20000230 = 0; *(uint64_t*)0x20000238 = 0; *(uint64_t*)0x20000240 = 0x2000; *(uint64_t*)0x20000248 = 0; *(uint64_t*)0x20000250 = 0; *(uint64_t*)0x20000258 = 0x4000; *(uint64_t*)0x20000260 = 0; *(uint64_t*)0x20000268 = 0; *(uint64_t*)0x20000270 = 0x41e0; *(uint64_t*)0x20000278 = 0; *(uint64_t*)0x20000280 = 0; *(uint64_t*)0x20000288 = 0x43e0; *(uint64_t*)0x20000290 = 0; *(uint64_t*)0x20000298 = 0; *(uint64_t*)0x200002a0 = 0x45e0; *(uint64_t*)0x200002a8 = 0; *(uint64_t*)0x200002b0 = 0; *(uint64_t*)0x200002b8 = 0x47e0; *(uint64_t*)0x200002c0 = 0; *(uint64_t*)0x200002c8 = 0; *(uint64_t*)0x200002d0 = 0x49e0; *(uint64_t*)0x200002d8 = 0; *(uint64_t*)0x200002e0 = 0; *(uint64_t*)0x200002e8 = 0x4be0; *(uint64_t*)0x200002f0 = 0; *(uint64_t*)0x200002f8 = 0; *(uint64_t*)0x20000300 = 0x4fe0; *(uint64_t*)0x20000308 = 0; *(uint64_t*)0x20000310 = 0; *(uint64_t*)0x20000318 = 0x51e0; *(uint64_t*)0x20000320 = 0; *(uint64_t*)0x20000328 = 0; *(uint64_t*)0x20000330 = 0x53e0; *(uint64_t*)0x20000338 = 0; *(uint64_t*)0x20000340 = 0; *(uint64_t*)0x20000348 = 0x57e0; *(uint64_t*)0x20000350 = 0; *(uint64_t*)0x20000358 = 0; *(uint64_t*)0x20000360 = 0x59e0; *(uint64_t*)0x20000368 = 0; *(uint64_t*)0x20000370 = 0; *(uint64_t*)0x20000378 = 0x5be0; *(uint64_t*)0x20000380 = 0; *(uint64_t*)0x20000388 = 0; *(uint64_t*)0x20000390 = 0x5de1; *(uint64_t*)0x20000398 = 0; *(uint64_t*)0x200003a0 = 0; *(uint64_t*)0x200003a8 = 0x5fe0; *(uint64_t*)0x200003b0 = 0; *(uint64_t*)0x200003b8 = 0; *(uint64_t*)0x200003c0 = 0x61e0; *(uint64_t*)0x200003c8 = 0; *(uint64_t*)0x200003d0 = 0; *(uint64_t*)0x200003d8 = 0x63e0; *(uint64_t*)0x200003e0 = 0; *(uint64_t*)0x200003e8 = 0; *(uint64_t*)0x200003f0 = 0x67e0; *(uint64_t*)0x200003f8 = 0; *(uint64_t*)0x20000400 = 0; *(uint64_t*)0x20000408 = 0x69e0; *(uint64_t*)0x20000410 = 0; *(uint64_t*)0x20000418 = 0; *(uint64_t*)0x20000420 = 0x6be0; *(uint64_t*)0x20000428 = 0; *(uint64_t*)0x20000430 = 0; *(uint64_t*)0x20000438 = 0x6fe0; *(uint64_t*)0x20000440 = 0; *(uint64_t*)0x20000448 = 0; *(uint64_t*)0x20000450 = 0x71e0; *(uint64_t*)0x20000458 = 0; *(uint64_t*)0x20000460 = 0; *(uint64_t*)0x20000468 = 0x73e0; *(uint64_t*)0x20000470 = 0; *(uint64_t*)0x20000478 = 0; *(uint64_t*)0x20000480 = 0x75e0; *(uint64_t*)0x20000488 = 0; *(uint64_t*)0x20000490 = 0; *(uint64_t*)0x20000498 = 0x77e0; *(uint64_t*)0x200004a0 = 0; *(uint64_t*)0x200004a8 = 0; *(uint64_t*)0x200004b0 = 0x79e0; *(uint64_t*)0x200004b8 = 0; *(uint64_t*)0x200004c0 = 0; *(uint64_t*)0x200004c8 = 0x7be0; *(uint64_t*)0x200004d0 = 0; *(uint64_t*)0x200004d8 = 0; *(uint64_t*)0x200004e0 = 0x7de0; *(uint64_t*)0x200004e8 = 0; *(uint64_t*)0x200004f0 = 0; *(uint64_t*)0x200004f8 = 0x7fe0; *(uint64_t*)0x20000500 = 0; *(uint64_t*)0x20000508 = 0; *(uint64_t*)0x20000510 = 0x81e0; *(uint64_t*)0x20000518 = 0; *(uint64_t*)0x20000520 = 0; *(uint64_t*)0x20000528 = 0x83e0; *(uint64_t*)0x20000530 = 0; *(uint64_t*)0x20000538 = 0; *(uint64_t*)0x20000540 = 0x85e0; *(uint64_t*)0x20000548 = 0; *(uint64_t*)0x20000550 = 0; *(uint64_t*)0x20000558 = 0x87e0; *(uint64_t*)0x20000560 = 0; *(uint64_t*)0x20000568 = 0; *(uint64_t*)0x20000570 = 0x89e0; *(uint64_t*)0x20000578 = 0; *(uint64_t*)0x20000580 = 0; *(uint64_t*)0x20000588 = 0x8be0; *(uint64_t*)0x20000590 = 0; *(uint64_t*)0x20000598 = 0; *(uint64_t*)0x200005a0 = 0x8de0; *(uint64_t*)0x200005a8 = 0; *(uint64_t*)0x200005b0 = 0; *(uint64_t*)0x200005b8 = 0x8fe0; *(uint64_t*)0x200005c0 = 0; *(uint64_t*)0x200005c8 = 0; *(uint64_t*)0x200005d0 = 0x91e0; *(uint64_t*)0x200005d8 = 0; *(uint64_t*)0x200005e0 = 0; *(uint64_t*)0x200005e8 = 0x93e0; *(uint64_t*)0x200005f0 = 0; *(uint64_t*)0x200005f8 = 0; *(uint64_t*)0x20000600 = 0x95e0; *(uint64_t*)0x20000608 = 0; *(uint64_t*)0x20000610 = 0; *(uint64_t*)0x20000618 = 0x97e0; *(uint64_t*)0x20000620 = 0; *(uint64_t*)0x20000628 = 0; *(uint64_t*)0x20000630 = 0x99e0; *(uint64_t*)0x20000638 = 0; *(uint64_t*)0x20000640 = 0; *(uint64_t*)0x20000648 = 0x9be0; *(uint64_t*)0x20000650 = 0; *(uint64_t*)0x20000658 = 0; *(uint64_t*)0x20000660 = 0x9de0; *(uint64_t*)0x20000668 = 0; *(uint64_t*)0x20000670 = 0; *(uint64_t*)0x20000678 = 0x9fe0; *(uint64_t*)0x20000680 = 0; *(uint64_t*)0x20000688 = 0; *(uint64_t*)0x20000690 = 0xa3e0; *(uint64_t*)0x20000698 = 0; *(uint64_t*)0x200006a0 = 0; *(uint64_t*)0x200006a8 = 0xa5e0; *(uint64_t*)0x200006b0 = 0; *(uint64_t*)0x200006b8 = 0; *(uint64_t*)0x200006c0 = 0xa7e0; *(uint64_t*)0x200006c8 = 0; *(uint64_t*)0x200006d0 = 0; *(uint64_t*)0x200006d8 = 0xa9e0; *(uint64_t*)0x200006e0 = 0; *(uint64_t*)0x200006e8 = 0; *(uint64_t*)0x200006f0 = 0xabe0; *(uint64_t*)0x200006f8 = 0; *(uint64_t*)0x20000700 = 0; *(uint64_t*)0x20000708 = 0xade0; *(uint64_t*)0x20000710 = 0; *(uint64_t*)0x20000718 = 0; *(uint64_t*)0x20000720 = 0xafe0; *(uint64_t*)0x20000728 = 0; *(uint64_t*)0x20000730 = 0; *(uint64_t*)0x20000738 = 0xb1e0; *(uint64_t*)0x20000740 = 0; *(uint64_t*)0x20000748 = 0; *(uint64_t*)0x20000750 = 0xb3e0; *(uint64_t*)0x20000758 = 0x2001bf00; memcpy((void*)0x2001bf00, "\x90\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00" "\x40\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00" "\xff\xff", 26); *(uint64_t*)0x20000760 = 0x1a; *(uint64_t*)0x20000768 = 0x1f; *(uint8_t*)0x2007dc00 = 0; syz_mount_image(0x20000000, 0x20000100, 0, 0x3a, 0x20000200, 0, 0x2007dc00); } int main(void) { syscall(__NR_mmap, 0x1ffff000ul, 0x1000ul, 0ul, 0x32ul, -1, 0ul); syscall(__NR_mmap, 0x20000000ul, 0x1000000ul, 7ul, 0x32ul, -1, 0ul); syscall(__NR_mmap, 0x21000000ul, 0x1000ul, 0ul, 0x32ul, -1, 0ul); do_sandbox_none(); return 0; }