Messages in this thread | | | Date | Tue, 24 Oct 2006 13:18:04 -0700 (PDT) | From | David Rientjes <> | Subject | Re: [PATCH] appletalk: prevent unregister_sysctl_table() with a NULL argument |
| |
On Tue, 24 Oct 2006, Akinobu Mita wrote:
> On Tue, Oct 24, 2006 at 02:38:24AM -0700, David Rientjes wrote: > > > The only way this would happen at atalk_unregister_sysctl is if the > > kmalloc failed on register_sysctl_table during init. In that case there > > is no need to unregister atalk in the first place since it never came up, > > Yes. this patch doesn't cause failure if sysctl registration failed. > It aims to avoid that minor possible NULL pointer dereference. >
That dereference should never be possible. If sysctl registration fails, it should not be left partially initialized so that it would ever need to be cleaned up later; it should just fail to register. So the fix, if indeed one is required in this instance that you have witnessed, should be an immediate response to an -ENOMEM on register_sysctl_table. Adding this to atalk_unregister_sysctl is incorrect because that function should only be entered given the condition that the register was successful, which in this case it was not.
David - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
| |