// https://syzkaller.appspot.com/bug?id=e5469128a20e1e23153b6e3259e41c0ef5f73a6e // 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 static unsigned long long procid; static __thread int skip_segv; static __thread jmp_buf segv_env; static void segv_handler(int sig, siginfo_t* info, void* ctx) { 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); } exit(sig); } static void install_segv_handler(void) { 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); \ } 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, long segments) { unsigned long i; struct fs_image_segment* segs = (struct fs_image_segment*)segments; if (nsegs > IMAGE_MAX_SEGMENTS) nsegs = IMAGE_MAX_SEGMENTS; for (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 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) { char loopname[64], fs[32], opts[256]; int loopfd, err = 0, res = -1; unsigned long i; NONFAILING(size = fs_image_segment_check(size, nsegs, segments)); int memfd = syscall(sys_memfd_create, "syz_mount_image", 0); if (memfd == -1) { err = errno; goto error; } if (ftruncate(memfd, size)) { err = errno; goto error_close_memfd; } for (i = 0; i < nsegs; i++) { struct fs_image_segment* segs = (struct fs_image_segment*)segments; int res1 = 0; NONFAILING(res1 = pwrite(memfd, segs[i].data, segs[i].size, segs[i].offset)); if (res1 < 0) { } } snprintf(loopname, sizeof(loopname), "/dev/loop%llu", procid); 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; } } mkdir((char*)dir, 0777); memset(fs, 0, sizeof(fs)); NONFAILING(strncpy(fs, (char*)fsarg, sizeof(fs) - 1)); memset(opts, 0, sizeof(opts)); NONFAILING(strncpy(opts, (char*)optsarg, 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"); } if (mount(loopname, (char*)dir, fs, flags, opts)) { err = errno; goto error_clear_loop; } res = 0; error_clear_loop: ioctl(loopfd, LOOP_CLR_FD, 0); error_close_loop: close(loopfd); error_close_memfd: close(memfd); error: errno = err; return res; } 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); install_segv_handler(); NONFAILING(memcpy((void*)0x20000180, "minix\000", 6)); NONFAILING(memcpy((void*)0x20000040, "./file0\000", 8)); NONFAILING(*(uint64_t*)0x20000000 = 0x20000100); NONFAILING(memcpy((void*)0x20000100, "\x60\x00\x84\xe0\x02\x00\x0a\x00\x90" "\x0c\xda\x40\xff\x1a\xd5\xc9\x8f\x13", 18)); NONFAILING(*(uint64_t*)0x20000008 = 0x12); NONFAILING(*(uint64_t*)0x20000010 = 0x400); NONFAILING(*(uint64_t*)0x20000018 = 0x20000780); NONFAILING(memcpy( (void*)0x20000780, "\xee\x9f\x84\xa4\x3e\xcc\xaf\x13\x15\xbb\x39\x7d\x00\xc1\xb6\xdd\x82\x0d" "\xd1\x39\x16\x18\x1d\xba\x62\x09\x38\xcb\x30\xf1\xc2\x1a\xfe\x3d\x92\x62" "\x98\xb2\x58\x34\xe8\x90\x09\x2d\x64\x2c\xaf\xe5\xdb\x21\xba\x94\x94\xfe" "\xbc\xf6\x60\x79\xb7\x22\xe7\x3b\xe3\xa8\x70\x8a\x36\x24\x25\x0f\x9f\x59" "\xfb\xbe\x94\x29\x97\xc6\xc1\xe8\x3a\x34\xe5\x77\x9e\x8a\x4f\x40\xfd\xb6" "\xff\xe5\x9f\xfe\x49\x03\x50\x0d\x3c\xd8\xc8\xf3\xed\x19\x60\x72\x8f\x2d" "\x94\xcf\x7f\xca\xf2\x92\x2f\x8a\xab\x3b\xec\xc6\x0c\x8d\x39\xdd\xf4\x3c" "\xd6\xd2\xe9\x30\x1d\xa3\xca\xa3\x57\x19\xf2\x5a\x83\x47\x85\x59\xe0\xe8" "\x91\xdc\xb7\x56\xee\x22\x96\x4d\x03\xf3\x75\x61\xf5\x79\x74\x90\xa0\xb9" "\x35\x06\x48\x28\x22\x07\x5b\xa9\x6d\xb3\x5a\x44\x0d\x04\x6e\x44\xeb\x4a" "\x79\x98\x6b\x51\x82\x81\x60\x90\x03\xb6\xfa\xe0\x4a\x18\xbe\x9a\x83\xce" "\x7e\xfa\x2a\xb8\x0f\x75\xc9\x0d\x78\xf0\xb4\x17\x9d\x67\x43\x76\xdb\x1f" "\x7a\xe8\x74\x56\x41\xad\xcd\xe0\xd2\x45\x72\x27\x44\xbc\xea\x2f\xac\x94" "\x45\x01\x4e\xe2\x29\x39\x85\x11\x95\x73\xff\xcc\x0c\x22\xeb\x07\x69\xde" "\x1e\x9e\x5d\xb5\x3a\xa3\x37\x8a\x44\x26\x50\x30\x10\xa7\xc6\x24\x72\x65" "\x83\x82\x11\x52\x7a\x01\x32\xcc\xf8\x83\xee\x08\xa6\xea\x1a\x78\x5e\x47" "\xce\x16\x66\x3f\x1c\x74\x4a\xf4\x92\x00\xd5\xf3\xbc\x32\x6e\x7d\x90\x89" "\xa5\xf1\x7d\x0a\xd0\x4d\xe5\xea\xe8\xd6\xd9\xea\x1a\x71\x4e\x35\xc5\xc3" "\x85\x5f\x06\xe4\x8c\x20\x5f\x9b\x6d\x08\x7b\xa7\xd3\xb6\x74\x5e\x65\x70" "\x0c\x00\x95\x72\xa6\x5b\x4b\xfb\xf6\x68\x78\x21\xbc\x72\x3b\x61\xb5\xab" "\xe7\x35\x7e\x68\xa9\xb0\x64\x0b\xfb\x9c\x01\x00\x00\x80\x00\x00\x00\x00" "\x0e\x84\x0e\xcf\x37\x9c\x57\x6c\x05\x75\x7d\x44\xb1\x9d\xe0\xe2\xaa\x36" "\x4c\x42\x15\x62\x19\xa7\x2c\xc9\x43\xa6\x0f\x04\x10\x89\x1e\xd1\x34\xf3" "\x5f\x5f\xe6\xb4\xcf\x3a\xbb\xcb\x98\x44\x36\x32\x23\x58\xa7\xc9\x39\x37" "\x24\x86\x0d\x87\x25\x39\x81\xf9\xe7\x9d\xbe\xb7\x89\x57\x7e\xad\x0e\xde" "\x31\xe1\x9a\x2b\x11\x4a\x0e\x4d\x82\xb3\xe1\x02\x3d\xd2\x8b\x63\x82\xe6" "\x7e\xbd\x46\xd2\x91\x2e\x55\xcf\x99\x28\xda\x32\xc1\x02\x7c\xef\x7c\x6c" "\x61\x0e\xa8\xfc\xe1\x49\xa7\xaf\x20\x22\x4b\x4e\x02\x86\x01\x93\x6e\xf9" "\xa7\x8d\x80\xff\x55\x67\x08\x4e\xc1\x28\x76\x6e\x82\x2d\x61\x24\x18\x6d" "\x82\xe7\x60\x12\x8d\xd7\xde\x26\x53\x93\x9d\x35\x3c\x12\xf9\x6d\xef\xf3" "\xa2\x8b\x02\x2c\x78\x4b\xd3\x7d\xf7\xf7\x66\x40\xbc\xbc\xb0\x1a\x46\x76" "\xd5\x8b\x3e\x9c\x2b\xaa\xe6\x62\x30\xe5\xf5\x4a\x37\x52\x7e\x81\x29\xd1" "\x61\xb0\xc0\x6f\x25\x64\x8c\x55\xa7\xe5\xb2\xdb\x52\x80\x53\xc3\xe3\x86" "\x4f\x41\x72\x8b\x79\x35\xe5\x75\x56\x8a\xd1\x14\xeb\x8c\x81\x1b\xf1\x9e" "\x07\xa3\x98\xba\xbb\xc6\x4f\xbe\xab\x84\x26\x88\x55\x47\x83\xed\x15\x51" "\x94\x9a\x79\x1e\x33\x79\x9e\x59\xa3\x4b\x6b\xda\xbc\x34\x58\xc3\x79\xc7" "\x35\x19\x82\x92\xe5\xa2\x72\xf5\x73\x49\x24\x9d\x2c\x8a\x9a\xa5\x8f\x38" "\x35\xa3\xe1\x71\x60\x83\xbb\x04\x64\xcb\xe1\x40\xd1\x58\x7a\x21\xe4\xec" "\x2a\xe1\xf3\xad\x81\x13\x4d\xf5\x59\x03\xff\xb8\xe1\x73\x64\x63\x52\x91" "\x5a\x2c\x70\x67\x09\xcf\x46\x53\x89\x78\x22\x4c\x0d\x6d\xc4\x37\xcb\xfc" "\x37\xab\xfb\xd1\xb7\x6f\xeb\x5c\xa3\xae\xb1\xac\x8c\xbd\x40\xd5\xba\x89" "\x6f\x79\xee\x8f\x76\xb0\x80\x9f\x59\xb8\x68\x62\x64\x87\x74\xd2\xac\xe9" "\x8b\x82\x5e\x7a\x46\x5b\x5d\xd8\x0e\x49\x19\x65\x97\x1e\x77\x97\xab\xa3" "\x96\x84\x41", 777)); NONFAILING(*(uint64_t*)0x20000020 = 0x309); NONFAILING(*(uint64_t*)0x20000028 = 0x34f9); syz_mount_image(0x20000180, 0x20000040, -1, 2, 0x20000000, 0x80, 0); NONFAILING(memcpy((void*)0x20000240, "./file0/file0\000", 14)); syscall(__NR_mkdir, 0x20000240ul, 0ul); return 0; }