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From: =?utf-8?B?SsO2cm4=?= Engel <joern@lazybastard.org>
To: Evgeniy Polyakov <johnpol@2ka.mipt.ru>
Subject: Re: Review status (Re: [PATCH] LogFS take three)
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On Sun, 20 May 2007 21:30:52 +0400, Evgeniy Polyakov wrote:
> 
> In that case segment size must be more than 32 bits, or below
> transformation will not be correct?

Must it?  If segment size is just 20bit then the filesystem may only be
52bit.  Or 51bit when using signed values.

> segsize is long, but should be u64 I think.

It could be s32 as well.

> static void fixup_from_wbuf(struct super_block *sb, struct logfs_area
> 	*area, void *read, u64 ofs, size_t readlen)
> 
> u32 read_start = ofs & (super->s_segsize - 1);
> u32 read_end = read_start + readlen;
> 
> And this can overflow, since readlen is size_t.

Theoretically yes.  Practically readlen is bounded to sb->blocksize plus
one header.  I'll start worrying about that when blocksize approaches
32bit limit.

> > If anyone can find similar bugs, the bounty is a beer or non-alcoholic
> > beverage of choice. :)
> 
> Stop kiling your kidneys, your health and promote such antisocial style
> of life, start drinking vodka instead.

I'm just a German.  Forgive me if I drink lesser beverages.

Jörn

-- 
Eighty percent of success is showing up.
-- Woody Allen