linux-kernel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Vinod Koul <vkoul@kernel.org>
To: Lv Yunlong <lyl2019@mail.ustc.edu.cn>
Cc: dave.jiang@intel.com, dmaengine@vger.kernel.org,
	linux-kernel@vger.kernel.org
Subject: Re: [PATCH v2] dma: Fix a double free in dma_async_device_register
Date: Mon, 12 Apr 2021 15:06:46 +0530	[thread overview]
Message-ID: <YHQUrpbSIXJ47nXL@vkoul-mobl.Dlink> (raw)
In-Reply-To: <20210331014458.3944-1-lyl2019@mail.ustc.edu.cn>

On 30-03-21, 18:44, Lv Yunlong wrote:
> In the first list_for_each_entry() macro of dma_async_device_register,
> it gets the chan from list and calls __dma_async_device_channel_register
> (..,chan). We can see that chan->local is allocated by alloc_percpu() and
> it is freed chan->local by free_percpu(chan->local) when
> __dma_async_device_channel_register() failed.
> 
> But after __dma_async_device_channel_register() failed, the caller will
> goto err_out and freed the chan->local in the second time by free_percpu().
> 
> The cause of this problem is forget to set chan->local to NULL when
> chan->local was freed in __dma_async_device_channel_register(). My
> patch sets chan->local to NULL when the callee failed to avoid double free.

Applied after fixing subsystem name, thanks

-- 
~Vinod

      parent reply	other threads:[~2021-04-12  9:52 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-03-31  1:44 [PATCH v2] dma: Fix a double free in dma_async_device_register Lv Yunlong
2021-03-31  2:48 ` Dave Jiang
2021-04-12  9:36 ` Vinod Koul [this message]

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=YHQUrpbSIXJ47nXL@vkoul-mobl.Dlink \
    --to=vkoul@kernel.org \
    --cc=dave.jiang@intel.com \
    --cc=dmaengine@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=lyl2019@mail.ustc.edu.cn \
    /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 a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).