Having the large CDB allocation logic in sd.c means that
scsi_io_completion does not have access to the command buffer. That in
turn causes garbage to be printed when a 32-byte command fails. Move the
command printing to sd_done where the command buffer is intact.  Clear
the command buffer pointer after the extended CDB has been freed.
Make scsi_print_command ignore commands with NULL CDB pointers to
inhibit printing of garbled command strings.
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Boaz Harrosh <bharrosh@panasas.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
 {
        int k;
 
+       if (cmd->cmnd == NULL)
+               return;
+
        scmd_printk(KERN_INFO, cmd, "CDB: ");
        print_opcode_name(cmd->cmnd, cmd->cmd_len);
 
 
                sd_dif_complete(SCpnt, good_bytes);
 
        if (scsi_host_dif_capable(sdkp->device->host, sdkp->protection_type)
-           == SD_DIF_TYPE2_PROTECTION && SCpnt->cmnd != SCpnt->request->cmd)
+           == SD_DIF_TYPE2_PROTECTION && SCpnt->cmnd != SCpnt->request->cmd) {
+
+               /* We have to print a failed command here as the
+                * extended CDB gets freed before scsi_io_completion()
+                * is called.
+                */
+               if (result)
+                       scsi_print_command(SCpnt);
+
                mempool_free(SCpnt->cmnd, sd_cdb_pool);
+               SCpnt->cmnd = NULL;
+               SCpnt->cmd_len = 0;
+       }
 
        return good_bytes;
 }