USB: serial: io_ti: fix heap overflow in build_i2c_fw_hdr()

In the Linux kernel, the following vulnerability has been resolved:

USB: serial: io_ti: fix heap overflow in build_i2c_fw_hdr()

build_i2c_fw_hdr() allocates a fixed-size buffer of

(16*1024 - 512) + sizeof(struct ti_i2c_firmware_rec) bytes, then

copies le16_to_cpu(img_header->Length) bytes into it without

validating that Length fits within the available space after the

firmware record header.

img_header->Length is a __le16 from the firmware file and can be

up to 65535. check_fw_sanity() validates the total firmware size

but not img_header->Length specifically.

Fix by rejecting images where img_header->Length exceeds the

available destination space.