Date: Mon, 23 Oct 2006 14:18:35 -0700
From: Greg KH <gregkh@suse.de>
To: Thomas Maier <balagi@justmail.de>
Cc: linux-kernel@vger.kernel.org
Subject: Re: [PATCH] 2.6.19-rc2-mm2 sysfs: sysfs_write_file() writes zero terminated data
Message-ID: <20061023211835.GA27613@suse.de>
References: <op.tht1yneaiudtyh@master> <20061022183924.GA18032@suse.de> <op.thv4lpt0iudtyh@master>
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On Mon, Oct 23, 2006 at 10:02:03PM +0200, Thomas Maier wrote:
> Hello,
> 
> Sorry, maybe i missed something, but according to the
> code in fs/sysfs/file.c the "write" sequence is:
> 
> - call to sysfs_write_file(ubuf, count)
> - if (!sysfsbuf->page)  alloc zeroed page
> - copy count bytes from ubuf to sysfsbuf->page
> - call store(sysfsbuf->page, count)
> 
> When you write again to the file before closing it
> (possible?!), and count is less the the previous count
> you may not pass a zero terminated string/data to store().

Yeah, that might happen, but writing to a sysfs file again after the
first time is not the normal case here.  I'll add your patch to the
queue to keep this from happening though, good catch.

greg k-h
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