From: Akinobu Mita <akinobu.mita@gmail.com>
Date: Wed, 26 Mar 2008 11:09:01 +0000 (+0100)
Subject: cdrom: protect cdrom_device_info list by mutex
X-Git-Tag: firefly_0821_release~21592^2~13
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=032d8d90ba23e1770604bbb1102ec77f5aa8ae44;p=firefly-linux-kernel-4.4.55.git

cdrom: protect cdrom_device_info list by mutex

This patch protects the list of cdrom_device_info by cdrom_mutex
when the file in /proc/sys/dev/cdrom/ is written.

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
---

diff --git a/drivers/cdrom/cdrom.c b/drivers/cdrom/cdrom.c
index fbcf4b3f8d0e..326ef1b4a4ea 100644
--- a/drivers/cdrom/cdrom.c
+++ b/drivers/cdrom/cdrom.c
@@ -3427,6 +3427,7 @@ static void cdrom_update_settings(void)
 {
 	struct cdrom_device_info *cdi;
 
+	mutex_lock(&cdrom_mutex);
 	for (cdi = topCdromPtr; cdi != NULL; cdi = cdi->next) {
 		if (autoclose && CDROM_CAN(CDC_CLOSE_TRAY))
 			cdi->options |= CDO_AUTO_CLOSE;
@@ -3445,6 +3446,7 @@ static void cdrom_update_settings(void)
 		else
 			cdi->options &= ~CDO_CHECK_TYPE;
 	}
+	mutex_unlock(&cdrom_mutex);
 }
 
 static int cdrom_sysctl_handler(ctl_table *ctl, int write, struct file * filp,