From: Dave Jiang <dave.jiang@intel.com>
To: Christophe JAILLET <christophe.jaillet@wanadoo.fr>,
vkoul@kernel.org, dan.j.williams@intel.com
Cc: dmaengine@vger.kernel.org, linux-kernel@vger.kernel.org,
kernel-janitors@vger.kernel.org
Subject: Re: [PATCH] dmaengine: idxd: Fix a possible NULL pointer dereference
Date: Thu, 29 Jul 2021 09:12:03 -0700 [thread overview]
Message-ID: <44c9607e-2cde-02b9-7e4e-68578a775fb3@intel.com> (raw)
In-Reply-To: <77f0dc4f3966591d1f0cffb614a94085f8895a85.1627560174.git.christophe.jaillet@wanadoo.fr>
On 7/29/2021 5:04 AM, Christophe JAILLET wrote:
> 'device_driver_attach()' dereferences its first argument (i.e. 'alt_drv')
> so it must not be NULL.
> Simplify the error handling logic about NULL 'alt_drv' in order to be
> more robust and future-proof.
>
> Fixes: 568b2126466f ("dmaengine: idxd: fix uninit var for alt_drv")
> Fixes: 6e7f3ee97bbe ("dmaengine: idxd: move dsa_drv support to compatible mode")
>
> Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Thanks for the cleanup.
Acked-by: Dave Jiang <dave.jiang@intel.com>
> ---
> drivers/dma/idxd/compat.c | 15 ++++-----------
> 1 file changed, 4 insertions(+), 11 deletions(-)
>
> diff --git a/drivers/dma/idxd/compat.c b/drivers/dma/idxd/compat.c
> index d7616c240dcd..3df21615f888 100644
> --- a/drivers/dma/idxd/compat.c
> +++ b/drivers/dma/idxd/compat.c
> @@ -45,23 +45,16 @@ static ssize_t bind_store(struct device_driver *drv, const char *buf, size_t cou
> idxd_dev = confdev_to_idxd_dev(dev);
> if (is_idxd_dev(idxd_dev)) {
> alt_drv = driver_find("idxd", bus);
> - if (!alt_drv)
> - return -ENODEV;
> } else if (is_idxd_wq_dev(idxd_dev)) {
> struct idxd_wq *wq = confdev_to_wq(dev);
>
> - if (is_idxd_wq_kernel(wq)) {
> + if (is_idxd_wq_kernel(wq))
> alt_drv = driver_find("dmaengine", bus);
> - if (!alt_drv)
> - return -ENODEV;
> - } else if (is_idxd_wq_user(wq)) {
> + else if (is_idxd_wq_user(wq))
> alt_drv = driver_find("user", bus);
> - if (!alt_drv)
> - return -ENODEV;
> - } else {
> - return -ENODEV;
> - }
> }
> + if (!alt_drv)
> + return -ENODEV;
>
> rc = device_driver_attach(alt_drv, dev);
> if (rc < 0)
next prev parent reply other threads:[~2021-07-29 16:13 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-07-29 12:04 [PATCH] dmaengine: idxd: Fix a possible NULL pointer dereference Christophe JAILLET
2021-07-29 16:12 ` Dave Jiang [this message]
2021-08-02 7:05 ` Vinod Koul
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=44c9607e-2cde-02b9-7e4e-68578a775fb3@intel.com \
--to=dave.jiang@intel.com \
--cc=christophe.jaillet@wanadoo.fr \
--cc=dan.j.williams@intel.com \
--cc=dmaengine@vger.kernel.org \
--cc=kernel-janitors@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=vkoul@kernel.org \
/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).