From 9183f01b5e6e32eb3f17b5f3f8d5ad5ac9786c49 Mon Sep 17 00:00:00 2001

From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Date: Thu, 6 May 2021 16:00:47 +0200

Subject: [PATCH] cdrom: gdrom: initialize global variable at init time

Git-commit: 9183f01b5e6e32eb3f17b5f3f8d5ad5ac9786c49

Patch-mainline: v5.13-rc3

References: git-fixes

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>

Acked-by: Takashi Iwai <tiwai@suse.de>

---

 drivers/cdrom/gdrom.c |    9 ++++++++-

 1 file changed, 8 insertions(+), 1 deletion(-)

--- a/drivers/cdrom/gdrom.c

+++ b/drivers/cdrom/gdrom.c

@@ -740,6 +740,13 @@ static const struct blk_mq_ops gdrom_mq_

 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_warning("ATA Probe for GDROM failed\n");

@@ -845,7 +852,7 @@ static struct platform_driver gdrom_driv

 static int __init init_gdrom(void)

 {

 	int rc;

-	gd.toc = NULL;

+

 	rc = platform_driver_register(&gdrom_driver);

 	if (rc)

 		return rc;