scsi: qedf: Ensure the copied buf is NUL terminated

[ Upstream commit d0184a375ee797eb657d74861ba0935b6e405c62 ]

Currently, we allocate a count-sized kernel buffer and copy count from
userspace to that buffer. Later, we use kstrtouint on this buffer but we
don't ensure that the string is terminated inside the buffer, this can
lead to OOB read when using kstrtouint. Fix this issue by using
memdup_user_nul instead of memdup_user.

Fixes: 61d8658b ("scsi: qedf: Add QLogic FastLinQ offload FCoE driver framework.")
Signed-off-by: Bui Quang Minh <minhquangbui99@gmail.com>
Link: https://lore.kernel.org/r/20240424-fix-oob-read-v2-4-f1f1b53a10f4@gmail.com


Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>