Re: [PATCH 1/3] audit: don't free_chunk() after fsnotify_add_mark()

[Eric Paris <eparis@redhat.com>]

On Mon, 2012-06-25 at 19:46 +0200, Miklos Szeredi wrote:
> From: Miklos Szeredi <mszeredi@suse.cz>
> 
> Don't do free_chunk() after fsnotify_add_mark().  That one does a delayed unref
> via the destroy list and this results in use-after-free.
> 
> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
> CC: stable@vger.kernel.org

Al, can you send these along?  I am not going to see a computer again
for a month.  Hurray!

Acked-by: Eric Paris <eparis@redhat.com>

> ---
>  kernel/audit_tree.c |    6 +++---
>  1 files changed, 3 insertions(+), 3 deletions(-)
> 
> diff --git a/kernel/audit_tree.c b/kernel/audit_tree.c
> index 5bf0790..d52d247 100644
> --- a/kernel/audit_tree.c
> +++ b/kernel/audit_tree.c
> @@ -259,7 +259,7 @@ static void untag_chunk(struct node *p)
>  
>  	fsnotify_duplicate_mark(&new->mark, entry);
>  	if (fsnotify_add_mark(&new->mark, new->mark.group, new->mark.i.inode, NULL, 1)) {
> -		free_chunk(new);
> +		fsnotify_put_mark(&new->mark);
>  		goto Fallback;
>  	}
>  
> @@ -322,7 +322,7 @@ static int create_chunk(struct inode *inode, struct audit_tree *tree)
>  
>  	entry = &chunk->mark;
>  	if (fsnotify_add_mark(entry, audit_tree_group, inode, NULL, 0)) {
> -		free_chunk(chunk);
> +		fsnotify_put_mark(entry);
>  		return -ENOSPC;
>  	}
>  
> @@ -396,7 +396,7 @@ static int tag_chunk(struct inode *inode, struct audit_tree *tree)
>  	fsnotify_duplicate_mark(chunk_entry, old_entry);
>  	if (fsnotify_add_mark(chunk_entry, chunk_entry->group, chunk_entry->i.inode, NULL, 1)) {
>  		spin_unlock(&old_entry->lock);
> -		free_chunk(chunk);
> +		fsnotify_put_mark(chunk_entry);
>  		fsnotify_put_mark(old_entry);
>  		return -ENOSPC;
>  	}