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Date: Wed, 19 Jun 2002 00:12:10 -0700
From: William Lee Irwin III <wli@holomorphy.com>
To: Linus Torvalds <torvalds@transmeta.com>
Cc: Andries.Brouwer@cwi.nl, Alexander Viro <viro@math.psu.edu>,
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Subject: Re: [PATCH+discussion] symlink recursion
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On Tue, Jun 18, 2002 at 04:57:06PM -0700, Linus Torvalds wrote:
> I see no advantages to handling it by hand, since this isn't even a very
> deep recursion, and since even if you do the recursive part by hand by a
> linked list you still need to limit the depth _anyway_ to avoid DoS
> attacks.

I see one: the space consumed by the explicitly managed stack is
known and control may be exerted over it. Also, the stack space
consumed by procedure calls is great enough on various non-x86 cpus
to make even shallow recursions problematic (ISTR 96B-120B/call with
a 4KB page in some prior discussions).


Cheers,
Bill
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