Message-ID: <51CAE1DD.8070301@hurleysoftware.com>
Date: Wed, 26 Jun 2013 08:43:09 -0400
From: Peter Hurley <peter@hurleysoftware.com>
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To: channing <chao.bi@intel.com>
CC: gregkh@linuxfoundation.org, jslaby@suse.cz, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] TTY: memory leakage in tty_buffer_find()
References: <1372236670.2390.12.camel@bichao>
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On 06/26/2013 04:51 AM, channing wrote:
>
> In tty_buffer_find(), it scans all tty buffers in
> free buffer queue, if it finds matched one,
> tty->buf.free will point to matched one's next buffer,
> so tty buffers that ahead of matched one are removed
> from free queue, they will never be used but they
> are not released, then memory leak happen.

Actually, the whole scan loop is wrong: only tty buffers of
size 256 are added to the free list.

So this can't leak because a buffer will never be found
mid-list.

Greg has a patch series from me that reduces this but it's not
yet in next.

Regards,
Peter Hurley

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