Re: [PATCH] Increase recursive symlink limit from 5 to 8

From: Måns Rullgård
Date: Thu Jan 15 2004 - 20:01:23 EST


GOTO Masanori <gotom@xxxxxxxxxxxx> writes:

> At Sun, 11 Jan 2004 10:49:30 +0100,
> Arjan van de Ven wrote:
>> > 6 does seem pretty low. What was the reason for setting it there? Is
>> > there a downside to increasing it?
>>
>> It was reduced down from 8 because it can lead to stack overflows.
>> Recursive links like this usually point at a quite broken filesystem
>> setup too afaik.
>
> But I still think 6 is too small from user level point of view, as
> Petter wrote. The example is /usr/lib library links. I got bug
> report which complained that a library want to use "bounce" link:
>
> /usr/lib/liba -> /etc/alternatives/liba -> /usr/lib/another/libb.
>
> If .so file uses major.minor scheme, then /usr/lib/liba.so links:
>
> /usr/lib/liba.so -> /usr/lib/liba.so.2 -> /usr/lib/liba.so.2.3
>
> and so on. It can easily exceed 6 symlinks. I think the correct fix
> is to make VFS not to overflow stacks. Is it allowable change?

One of the reasons for the limit is that it doesn't require any
special detection of circular links.

--
Måns Rullgård
mru@xxxxxx

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