scsi: sd: Fix scsi_mode_sense caller's sshdr use

The sshdr passed into scsi_execute_cmd is only initialized if
scsi_execute_cmd returns >= 0, and scsi_mode_sense will convert all non
good statuses like check conditions to -EIO. This has scsi_mode_sense
callers that were possibly accessing an uninitialized sshdrs to only
access it if we got -EIO.

Signed-off-by: Mike Christie <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Reviewed-by: Christoph Hellwig <[email protected]>
Reviewed-by: Martin Wilck <[email protected]>
Signed-off-by: Martin K. Petersen <[email protected]>

Author: mikechristie

drivers/scsi/sd.c

@@ -2890,7 +2890,7 @@ sd_read_cache_type(struct scsi_disk *sdkp, unsigned char *buffer)
 	}
 
 bad_sense:
-	if (scsi_sense_valid(&sshdr) &&
+	if (res == -EIO && scsi_sense_valid(&sshdr) &&
 	    sshdr.sense_key == ILLEGAL_REQUEST &&
 	    sshdr.asc == 0x24 && sshdr.ascq == 0x0)
 		/* Invalid field in CDB */
@@ -2938,7 +2938,7 @@ static void sd_read_app_tag_own(struct scsi_disk *sdkp, unsigned char *buffer)
 		sd_first_printk(KERN_WARNING, sdkp,
 			  "getting Control mode page failed, assume no ATO\n");
 
-		if (scsi_sense_valid(&sshdr))
+		if (res == -EIO && scsi_sense_valid(&sshdr))
 			sd_print_sense_hdr(sdkp, &sshdr);
 
 		return;