From: Andrew Morton <akpm@linux-foundation.org>
To: Paul Mundt <lethal@linux-sh.org>
Cc: adrian@newgolddream.dyndns.info, lkmladrian@gmail.com,
linux-kernel@vger.kernel.org, linux-sh@vger.kernel.org,
penberg@cs.helsinki.fi, dbaryshkov@gmail.com,
penguin-kernel@i-love.sakura.ne.jp, lg@denx.de,
hannes@cmpxchg.org
Subject: Re: [PATCH] dma: fix up broken comparison in
Date: Tue, 27 Jan 2009 21:48:31 +0000 [thread overview]
Message-ID: <20090127134831.3dd04182.akpm@linux-foundation.org> (raw)
In-Reply-To: <20090121081118.GA14537@linux-sh.org>
On Wed, 21 Jan 2009 17:11:19 +0900
Paul Mundt <lethal@linux-sh.org> wrote:
> @@ -118,31 +118,32 @@ int dma_alloc_from_coherent(struct device *dev, ssize_t size,
> mem = dev->dma_mem;
> if (!mem)
> return 0;
> - if (unlikely(size > mem->size))
> - return 0;
> +
> + *ret = NULL;
> +
> + if (unlikely(size > (mem->size << PAGE_SHIFT)))
> + goto err;
Looks a bit broken on 64-bit.
`size' is ssize_t (long).
`mem->size' is `int'.
The left shift can overflow and cause badnesses.
> + *dma_handle = mem->device_base + (pageno << PAGE_SHIFT);
> + *ret = mem->virt_base + (pageno << PAGE_SHIFT);
Ditto.
Maybe it's a can't-happen (why?), but...
WARNING: multiple messages have this Message-ID (diff)
From: Andrew Morton <akpm@linux-foundation.org>
To: Paul Mundt <lethal@linux-sh.org>
Cc: adrian@newgolddream.dyndns.info, lkmladrian@gmail.com,
linux-kernel@vger.kernel.org, linux-sh@vger.kernel.org,
penberg@cs.helsinki.fi, dbaryshkov@gmail.com,
penguin-kernel@i-love.sakura.ne.jp, lg@denx.de,
hannes@cmpxchg.org
Subject: Re: [PATCH] dma: fix up broken comparison in dma_alloc_from_coherent
Date: Tue, 27 Jan 2009 13:48:31 -0800 [thread overview]
Message-ID: <20090127134831.3dd04182.akpm@linux-foundation.org> (raw)
In-Reply-To: <20090121081118.GA14537@linux-sh.org>
On Wed, 21 Jan 2009 17:11:19 +0900
Paul Mundt <lethal@linux-sh.org> wrote:
> @@ -118,31 +118,32 @@ int dma_alloc_from_coherent(struct device *dev, ssize_t size,
> mem = dev->dma_mem;
> if (!mem)
> return 0;
> - if (unlikely(size > mem->size))
> - return 0;
> +
> + *ret = NULL;
> +
> + if (unlikely(size > (mem->size << PAGE_SHIFT)))
> + goto err;
Looks a bit broken on 64-bit.
`size' is ssize_t (long).
`mem->size' is `int'.
The left shift can overflow and cause badnesses.
> + *dma_handle = mem->device_base + (pageno << PAGE_SHIFT);
> + *ret = mem->virt_base + (pageno << PAGE_SHIFT);
Ditto.
Maybe it's a can't-happen (why?), but...
next prev parent reply other threads:[~2009-01-27 21:48 UTC|newest]
Thread overview: 23+ messages / expand[flat|nested] mbox.gz Atom feed top
2009-01-20 21:48 [PATCH] dma: fix up broken comparison in dma_alloc_from_coherent Adrian McMenamin
2009-01-20 21:55 ` [PATCH] dma: fix up broken comparison in Adrian McMenamin
2009-01-20 21:55 ` [PATCH] dma: fix up broken comparison in dma_alloc_from_coherent Adrian McMenamin
2009-01-21 3:39 ` Paul Mundt
2009-01-21 3:39 ` Paul Mundt
2009-01-21 8:11 ` Paul Mundt
2009-01-21 8:11 ` Paul Mundt
2009-01-21 8:29 ` Guennadi Liakhovetski
2009-01-21 8:29 ` Guennadi Liakhovetski
2009-01-21 8:30 ` Paul Mundt
2009-01-21 8:30 ` Paul Mundt
2009-01-27 21:48 ` Andrew Morton [this message]
2009-01-27 21:48 ` Andrew Morton
2009-01-27 22:54 ` Paul Mundt
2009-01-27 22:54 ` Paul Mundt
2009-01-28 8:36 ` Guennadi Liakhovetski
2009-01-28 8:36 ` Guennadi Liakhovetski
2009-02-06 12:22 ` [PATCH] fix broken size test in bitmap_find_free_region() Guennadi Liakhovetski
2009-02-06 12:22 ` Guennadi Liakhovetski
2009-02-06 21:29 ` Andrew Morton
2009-02-06 21:29 ` Andrew Morton
2009-02-06 22:30 ` Guennadi Liakhovetski
2009-02-06 22:30 ` Guennadi Liakhovetski
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20090127134831.3dd04182.akpm@linux-foundation.org \
--to=akpm@linux-foundation.org \
--cc=adrian@newgolddream.dyndns.info \
--cc=dbaryshkov@gmail.com \
--cc=hannes@cmpxchg.org \
--cc=lethal@linux-sh.org \
--cc=lg@denx.de \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-sh@vger.kernel.org \
--cc=lkmladrian@gmail.com \
--cc=penberg@cs.helsinki.fi \
--cc=penguin-kernel@i-love.sakura.ne.jp \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.