From mboxrd@z Thu Jan  1 00:00:00 1970
From: Andi Kleen <andi@firstfloor.org>
Subject: Re: [PATCH 2/2] Perform check in iov_iter_fault_in_readable() by check_readable_bytes()
Date: Fri, 15 May 2009 11:38:38 +0200
Message-ID: <20090515093838.GB16682@one.firstfloor.org>
References: <1242317939-15392-1-git-send-email-v.mayatskih@gmail.com> <1242317939-15392-3-git-send-email-v.mayatskih@gmail.com> <87k54iq2gv.fsf@basil.nowhere.org> <871vqqkdf0.wl%vmayatsk@redhat.com>
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Cc: Andi Kleen <andi@firstfloor.org>, Josef Bacik <josef@redhat.com>,
	sandeen@redhat.com, linux-fsdevel@vger.kernel.org,
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To: Vitaly Mayatskikh <v.mayatskih@gmail.com>
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> ptr = mmap(0, page_size, ....);
> ...
> write(fd, ptr + page_size - 256, 512);
> 
> Write() will fail here, but it can write first 256 bytes. Previously,
> all 512 bytes were proceeded, but last 256 bytes were zeroed, and
> sys_write() returned 256. Not very nice too. 

Is that really something that users rely on? It looks like a seriously
broken user program. Which one is that? (just that I can avoid it :)

-Andi

-- 
ak@linux.intel.com -- Speaking for myself only.