Transport drivers allocate memory for iSCSI hdr in alloc_pdu() and assign
it to task->hdr. In case of TMF task->hdr will be NULL resulting in NULL
pointer dereference.
2. ISCSI_OP_SCSI_DATA_OUT - In this case transport driver can free the
memory for iSCSI hdr after transmitting the pdu so task->hdr can be NULL or
invalid.
This patch fixes this issue by removing task->hdr->opcode from the printk
statement.
Signed-off-by: Varun Prakash <varun@chelsio.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>