static int tg3_do_mem_test(struct tg3 *tp, u32 offset, u32 len)
{
	static const u32 test_pattern[] = { 0x00000000, 0xffffffff, 0xaa55a55a };
	int i;
	u32 j;

	for (i = 0; i < ARRAY_SIZE(test_pattern); i++) {
		for (j = 0; j < len; j += 4) {
			u32 val;

			tg3_write_mem(tp, offset + j, test_pattern[i]);
			tg3_read_mem(tp, offset + j, &val);
			if (val != test_pattern[i])
				return -EIO;
		}
	}
	return 0;
}

The product performs operations on a memory buffer, but it reads from or writes to a memory location outside the buffer's intended boundary. This may result in read or write operations on unexpected memory locations that could be linked to other variables, data structures, or internal program data.