linux-kernel - [PATCH AUTOSEL 4.9 14/19] cdrom: gdrom: initialize global variable at init time

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20210524145106.2499571-14-sashal@kernel.org>
Date:   Mon, 24 May 2021 10:51:01 -0400
From:   Sasha Levin <sashal@...nel.org>
To:     linux-kernel@...r.kernel.org, stable@...r.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        Peter Rosin <peda@...ntia.se>, Jens Axboe <axboe@...nel.dk>,
        Sasha Levin <sashal@...nel.org>
Subject: [PATCH AUTOSEL 4.9 14/19] cdrom: gdrom: initialize global variable at init time

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

[ Upstream commit 9183f01b5e6e32eb3f17b5f3f8d5ad5ac9786c49 ]

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@...ntia.se>
Cc: Jens Axboe <axboe@...nel.dk>
Reviewed-by: Peter Rosin <peda@...ntia.se>
Link: https://lore.kernel.org/r/YJP2j6AU82MqEY2M@kroah.com
Signed-off-by: Greg Kroah-Hartman <gregkh@...uxfoundation.org>
Signed-off-by: Sasha Levin <sashal@...nel.org>
---
 drivers/cdrom/gdrom.c | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/drivers/cdrom/gdrom.c b/drivers/cdrom/gdrom.c
index 1852d19d0d7b..2a78aeea84a2 100644
--- a/drivers/cdrom/gdrom.c
+++ b/drivers/cdrom/gdrom.c
@@ -773,6 +773,13 @@ static int probe_gdrom_setupqueue(void)
 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");
@@ -865,7 +872,7 @@ 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;
-- 
2.30.2