scsi: always zero sshdr in scsi_normalize_sense

This gives us a clear state even if a command didn't return sense data.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NHannes Reinecke <hare@suse.de>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

drivers/scsi/scsi_common.c

@@ -137,11 +137,11 @@ EXPORT_SYMBOL(int_to_scsilun);
 bool scsi_normalize_sense(const u8 *sense_buffer, int sb_len,
 			  struct scsi_sense_hdr *sshdr)
 {
+	memset(sshdr, 0, sizeof(struct scsi_sense_hdr));
+
 	if (!sense_buffer || !sb_len)
 		return false;
 
-	memset(sshdr, 0, sizeof(struct scsi_sense_hdr));
-
 	sshdr->response_code = (sense_buffer[0] & 0x7f);
 
 	if (!scsi_sense_valid(sshdr))