scsi: NCR5380: Initialize buffer for MSG IN and STATUS transfers

Following an incomplete transfer in MSG IN phase, the driver would not
notice the problem and would make use of invalid data. Initialize 'tmp'
appropriately and bail out if no message was received. For STATUS phase,
preserve the existing status code unless a new value was transferred.

Tested-by: Stan Johnson <userm57@yahoo.com>
Signed-off-by: Finn Thain <fthain@linux-m68k.org>
Link: https://lore.kernel.org/r/52e02a8812ae1a2d810d7f9f7fd800c3ccc320c4.1723001788.git.fthain@linux-m68k.org
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

diff --git a/drivers/scsi/NCR5380.c b/drivers/scsi/NCR5380.c
index 00e2451..4fcb73b 100644 (file)
--- a/drivers/scsi/NCR5380.c
+++ b/drivers/scsi/NCR5380.c
@@ -1807,8 +1807,11 @@ static void NCR5380_information_transfer(struct Scsi_Host *instance)
                                return;
                        case PHASE_MSGIN:
                                len = 1;
+                               tmp = 0xff;
                                data = &tmp;
                                NCR5380_transfer_pio(instance, &phase, &len, &data, 0);
+                               if (tmp == 0xff)
+                                       break;
                                ncmd->message = tmp;
 
                                switch (tmp) {
@@ -1996,6 +1999,7 @@ static void NCR5380_information_transfer(struct Scsi_Host *instance)
                                break;
                        case PHASE_STATIN:
                                len = 1;
+                               tmp = ncmd->status;
                                data = &tmp;
                                NCR5380_transfer_pio(instance, &phase, &len, &data, 0);
                                ncmd->status = tmp;