linux-kernel - [patch] Crash on evdev disconnect.

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Date:	Mon, 7 Aug 2006 11:59:17 -0400
From:	"Zephaniah E. Hull" <warp@...allh.com>
To:	dtor_core@...ritech.net
Cc:	linux-input@...ey.karlin.mff.cuni.cz, linux-kernel@...r.kernel.org
Subject: [patch] Crash on evdev disconnect.

While trying to figure out the best way to handle an odd mouse, I found
that we oopsed when doing a rmmod on usbhid while someone had a USB
device open through evdev.

We try to loop through evdev->list, calling kill_fasync on each member,
however by the time we try to get the next pointer, we have already
freed the member and poisoned the next/last.

The fix is fairly simple, and if nobody objects I think we should try
and get this into -stable too.

Signed-off-by: "Zephaniah E. Hull" <warp@...allh.com>

diff -ur linux-test/drivers/input/evdev.c linux-2.6/drivers/input/evdev.c
--- linux-test/drivers/input/evdev.c	2006-07-24 23:36:01.000000000 -0400
+++ linux-2.6/drivers/input/evdev.c	2006-08-07 11:41:13.000000000 -0400
@@ -659,7 +659,7 @@
 static void evdev_disconnect(struct input_handle *handle)
 {
 	struct evdev *evdev = handle->private;
-	struct evdev_list *list;
+	struct evdev_list *list, *next;

 	sysfs_remove_link(&input_class.subsys.kset.kobj, evdev->name);
 	class_device_destroy(&input_class,
@@ -669,7 +669,7 @@
 	if (evdev->open) {
 		input_close_device(handle);
 		wake_up_interruptible(&evdev->wait);
-		list_for_each_entry(list, &evdev->list, node)
+		list_for_each_entry_safe(list, next, &evdev->list, node)
 			kill_fasync(&list->fasync, SIGIO, POLL_HUP);
 	} else
 		evdev_free(evdev);

-- 
	  1024D/E65A7801 Zephaniah E. Hull <warp@...allh.com>
	   92ED 94E4 B1E6 3624 226D  5727 4453 008B E65A 7801
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