// https://syzkaller.appspot.com/bug?id=c2fd07ae5213991a1b95eadee9205b41ac1aa6e2 // autogenerated by syzkaller (http://github.com/google/syzkaller) #define _GNU_SOURCE #include #include #include #include #include #include #include #include #include #include #include #include #include extern unsigned long long procid; struct fs_image_segment { void* data; uintptr_t size; uintptr_t offset; }; #define IMAGE_MAX_SEGMENTS 4096 #define IMAGE_MAX_SIZE (32 << 20) #define SYZ_memfd_create 319 static uintptr_t syz_mount_image(uintptr_t fs, uintptr_t dir, uintptr_t size, uintptr_t nsegs, uintptr_t segments, uintptr_t flags, uintptr_t opts) { char loopname[64]; int loopfd, err = 0, res = -1; uintptr_t 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; int memfd = syscall(SYZ_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++) { if (pwrite(memfd, segs[i].data, segs[i].size, segs[i].offset) < 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); if (strcmp((char*)fs, "iso9660") == 0) flags |= MS_RDONLY; if (mount(loopname, (char*)dir, (char*)fs, flags, (char*)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; } unsigned long long procid; void loop() { memcpy((void*)0x20000000, "hfs", 4); memcpy((void*)0x20000100, "./file0", 8); *(uint64_t*)0x20000200 = 0x20010000; memcpy((void*)0x20010000, "\x42\x44\xd6\xe3\xc6\xbd\xd6\xe3\xc6\xbd\x01\x00\x00\x00\x00\x03\x00" "\x00\x01\xff\x00\x00\x20\x00\x00\x00\x80\x00\x00\x04\x00\x00\x00\x10" "\x01\xf7\x03\x73\x79\x7a\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00" "\x00\x00\x00\x00\x91\x47\x8d\xdc\x4a\x34\x71\x4a\x00\x00\x00\x00\x00" "\x00\x00\x00\x00\x00\x02\x00\x00\x80\x00\x00\x00\x80\x00\x00\x00\x00" "\x00\x00\x00\x00\x00\x04\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00" "\x00\x00\x00\x00\x00\x00\x00\x63\x6e\x65\x00\x00\x00\x00\x12\x41\x5e" "\x59\xf7\x48\x66\x89\x00\x00\x00\x80\x00\x00\x00\x00\x04\x00\x00\x00" "\x00\x00\x00\x00\x00\x00\x00\x80\x00\x00\x04\x00\x04\x00\x00\x00\x00" "\x00\x00", 155); *(uint64_t*)0x20000208 = 0x9b; *(uint64_t*)0x20000210 = 0x400; *(uint64_t*)0x20000218 = 0x20010400; *(uint64_t*)0x20000220 = 0; *(uint64_t*)0x20000228 = 0x9dc; *(uint64_t*)0x20000230 = 0x20000380; *(uint64_t*)0x20000238 = 0; *(uint64_t*)0x20000240 = 0x8be0; syz_mount_image(0x20000000, 0x20000100, 0x400000, 3, 0x20000200, 0, 0x200001c0); } int main() { syscall(__NR_mmap, 0x20000000, 0x1000000, 3, 0x32, -1, 0); loop(); return 0; }