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From: Linus Torvalds <torvalds@linux-foundation.org>
Date: Tue, 13 Dec 2016 11:26:44 -0800
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Subject: Re: [PATCH v3] siphash: add cryptographically secure hashtable function
To: Eric Biggers <ebiggers3@gmail.com>
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On Tue, Dec 13, 2016 at 12:39 AM, Eric Biggers <ebiggers3@gmail.com> wrote:
>
> Hmm, I don't think you can really do load_unaligned_zeropad() without first
> checking for 'left != 0'.

Right you are. If the allocation is at the end of a page, the 0-size
case would be entirely outside the page and there's no fixup.

Of course, that never happens in normal code, but DEBUG_PAGE_ALLOC can
trigger it.

              Linus