scsi: libiscsi: fix possible NULL pointer dereference in case of TMF
[ Upstream commit a17037e7d59075053b522048742a08ac9500bde8 ]
In iscsi_check_tmf_restrictions() task->hdr is dereferenced to print the
opcode, it is possible that task->hdr is NULL.
There are two cases based on opcode argument:
1. ISCSI_OP_SCSI_CMD - In this case alloc_pdu() is called
after iscsi_check_tmf_restrictions()
iscsi_prep_scsi_cmd_pdu() -> iscsi_check_tmf_restrictions() -> alloc_pdu().
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>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
1 file changed