static int uvesafb_vbe_getpmi(struct uvesafb_ktask *task,
			      struct uvesafb_par *par)
{
	int i, err;

	uvesafb_reset(task);
	task->t.regs.eax = 0x4f0a;
	task->t.regs.ebx = 0x0;
	err = uvesafb_exec(task);

	if ((task->t.regs.eax & 0xffff) != 0x4f || task->t.regs.es < 0xc000) {
		par->pmi_setpal = par->ypan = 0;
	} else {
		par->pmi_base = (u16 *)phys_to_virt(((u32)task->t.regs.es << 4)
						+ task->t.regs.edi);
		par->pmi_start = (u8 *)par->pmi_base + par->pmi_base[1];
		par->pmi_pal = (u8 *)par->pmi_base + par->pmi_base[2];
		pr_info("protected mode interface info at %04x:%04x\n",
			(u16)task->t.regs.es, (u16)task->t.regs.edi);
		pr_info("pmi: set display start = %p, set palette = %p\n",
			par->pmi_start, par->pmi_pal);

		if (par->pmi_base[3]) {
			pr_info("pmi: ports =");
			for (i = par->pmi_base[3]/2;
					par->pmi_base[i] != 0xffff; i++)
				pr_cont(" %x", par->pmi_base[i]);
			pr_cont("\n");

			if (par->pmi_base[i] != 0xffff) {
				pr_info("can't handle memory requests, pmi disabled\n");
				par->ypan = par->pmi_setpal = 0;
			}
		}
	}
	return 0;
}

The product 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 occurs when an integer value is incremented to a value that is too large to store in the associated representation. When this occurs, the value may become a very small or negative number.