Re: [PATCH] kernel: auditfilter: looping issue, memory leak if has 2 or more AUDIT_FILTERKEYs

[Chen Gang <gang.chen@asianux.com>]

On 2013年04月11日 21:40, Eric Paris wrote:
>> >   can we add it in audit_free_rule ?
>> > 
>> >   maybe like this:
>> > 
>> > @@ -75,6 +75,8 @@ static inline void audit_free_rule(struct audit_entry *e)
>> >  	/* some rules don't have associated watches */
>> >  	if (erule->watch)
>> >  		audit_put_watch(erule->watch);
>> > +	if (erule->tree)
>> > +		audit_put_tree(erule->tree);
>> >  	if (erule->fields)
>> >  		for (i = 0; i < erule->field_count; i++) {
>> >  			struct audit_field *f = &erule->fields[i];
> Where does the tree information get freed normally?  That's the code you need to run down.  You don't want to start getting double frees on the non-error case.  I'll try to dig into it if Al doesn't.  It's easy to show the leak on current kernels.
> 

  I think:
    it is in function audit_del_rule. when del, also set NULL.
    so the deletion in audit_free_rule is safe.
    the process of erule->watch and erule->tree are similar.

  please check, thanks.


> while(1)
>     auditctl -a exit,always -w /etc -F auid=-1
> 
> 
> 

  it is valuable to me, thanks.



-- 
Chen Gang

Asianux Corporation