cdrom: gdrom: initialize global variable at init time

As Peter points out, if we were to disconnect and then reconnect this
driver from a device, the "global" state of the device would contain odd
values and could cause problems.  Fix this up by just initializing the
whole thing to 0 at probe() time.

Ideally this would be a per-device variable, but given the age and the
total lack of users of it, that would require a lot of s/./->/g changes
for really no good reason.

Reported-by: Peter Rosin <peda@axentia.se>
Cc: Jens Axboe <axboe@kernel.dk>
Reviewed-by: Peter Rosin <peda@axentia.se>
Link: https://lore.kernel.org/r/YJP2j6AU82MqEY2M@kroah.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/cdrom/gdrom.c b/drivers/cdrom/gdrom.c
index 6c4f613..c6d8c0f 100644 (file)
--- a/drivers/cdrom/gdrom.c
+++ b/drivers/cdrom/gdrom.c
@@ -744,6 +744,13 @@ static const struct blk_mq_ops gdrom_mq_ops = {
 static int probe_gdrom(struct platform_device *devptr)
 {
        int err;
+
+       /*
+        * Ensure our "one" device is initialized properly in case of previous
+        * usages of it
+        */
+       memset(&gd, 0, sizeof(gd));
+
        /* Start the device */
        if (gdrom_execute_diagnostic() != 1) {
                pr_warn("ATA Probe for GDROM failed\n");
@@ -847,7 +854,7 @@ static struct platform_driver gdrom_driver = {
 static int __init init_gdrom(void)
 {
        int rc;
-       gd.toc = NULL;
+
        rc = platform_driver_register(&gdrom_driver);
        if (rc)
                return rc;