Date: Wed, 28 May 2003 01:31:05 +0100
From: viro@parcelfarce.linux.theplanet.co.uk
To: Linus Torvalds <torvalds@transmeta.com>
Cc: linux-kernel@vger.kernel.org
Subject: [PATCH] procfs bug exposed by cdev changes
Message-ID: <20030528003105.GD27916@parcelfarce.linux.theplanet.co.uk>
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	fs/inode.c assumes that any ->delete_inode() will call clear_inode().
procfs instance doesn't.  It had passed unpunished for a while; cdev changes
combined with ALSA creating character devices in procfs made it fatal.

	Patch follows.  It had fixed ALSA-triggered memory corruption here -
what happens in vanilla 2.5.70 is that clear_inode() is not called when
procfs character device inodes are freed.  That leaves a freed inode on
a cyclic list, with obvious unpleasantness following when we try to traverse
it (e.g. when unregistering a device).

	Please, apply.  Folks who'd seen oopsen/memory corruption after
ALSA access - please, check if that fixes all problems.

--- C70/fs/proc/inode.c	Mon May 26 22:21:40 2003
+++ C70-current/fs/proc/inode.c	Tue May 27 20:07:01 2003
@@ -61,8 +61,6 @@
 	struct proc_dir_entry *de;
 	struct task_struct *tsk;
 
-	inode->i_state = I_CLEAR;
-
 	/* Let go of any associated process */
 	tsk = PROC_I(inode)->task;
 	if (tsk)
@@ -75,6 +73,7 @@
 			module_put(de->owner);
 		de_put(de);
 	}
+	clear_inode(inode);
 }
 
 struct vfsmount *proc_mnt;
-
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