scsi: qla2xxx: Sanitize payload size to prevent member overflow

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

scsi: qla2xxx: Sanitize payload size to prevent member overflow

In qla27xx_copy_fpin_pkt() and qla27xx_copy_multiple_pkt(), the frame_size

reported by firmware is used to calculate the copy length into

item->iocb. However, the iocb member is defined as a fixed-size 64-byte

array within struct purex_item.

If the reported frame_size exceeds 64 bytes, subsequent memcpy calls will

overflow the iocb member boundary. While extra memory might be allocated,

this cross-member write is unsafe and triggers warnings under

CONFIG_FORTIFY_SOURCE.

Fix this by capping total_bytes to the size of the iocb member (64 bytes)

before allocation and copying. This ensures all copies remain within the

bounds of the destination structure member.