All of lore.kernel.org
 help / color / mirror / Atom feed
From: "Russell King (Oracle)" <linux@armlinux.org.uk>
To: Dan Carpenter <dan.carpenter@oracle.com>
Cc: Pavel Skripkin <paskripkin@gmail.com>,
	Yanfei Xu <yanfei.xu@windriver.com>,
	Bartosz Golaszewski <bgolaszewski@baylibre.com>,
	andrew@lunn.ch, hkallweit1@gmail.com, davem@davemloft.net,
	kuba@kernel.org, p.zabel@pengutronix.de,
	syzbot+398e7dc692ddbbb4cfec@syzkaller.appspotmail.com,
	linux-kernel@vger.kernel.org, netdev@vger.kernel.org,
	Dongliang Mu <mudongliangabcd@gmail.com>
Subject: Re: [PATCH] net: mdiobus: Fix memory leak in __mdiobus_register
Date: Tue, 28 Sep 2021 16:41:36 +0100	[thread overview]
Message-ID: <YVM3sFBIHzEnshvd@shell.armlinux.org.uk> (raw)
In-Reply-To: <20210928135207.GP2083@kadam>

On Tue, Sep 28, 2021 at 04:52:07PM +0300, Dan Carpenter wrote:
> On Tue, Sep 28, 2021 at 01:58:00PM +0100, Russell King (Oracle) wrote:
> >
> > This thread seems to be getting out of hand.
> 
> The thread was closed.  We need to revert Yanfei's patch and apply
> Pavel's patch.  He's going to resend.
> 
> > So, I would suggest a simple fix is to set bus->state to
> > MDIOBUS_UNREGISTERED immediately _after_ the successful
> > device_register().
> 
> Not after.  It has to be set to MDIOBUS_UNREGISTERED if device_register()
> fails, otherwise there will still be a leak.

Ah yes, you are correct - the device name may not be freed. Also...

 * NOTE: _Never_ directly free @dev after calling this function, even
 * if it returned an error! Always use put_device() to give up your
 * reference instead.

So yes, we must set to MDIOBUS_UNREGISTERED even if device_register()
fails.

-- 
RMK's Patch system: https://www.armlinux.org.uk/developer/patches/
FTTP is here! 40Mbps down 10Mbps up. Decent connectivity at last!

  reply	other threads:[~2021-09-28 15:41 UTC|newest]

Thread overview: 23+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-09-26  4:53 [PATCH] net: mdiobus: Fix memory leak in __mdiobus_register Yanfei Xu
2021-09-26 15:34 ` Andrew Lunn
2021-09-27 12:30 ` patchwork-bot+netdevbpf
2021-09-28  8:55 ` Dan Carpenter
2021-09-28  9:26   ` Dan Carpenter
2021-09-28  9:45     ` Pavel Skripkin
2021-09-28 10:39       ` Dan Carpenter
2021-09-28 10:46         ` Pavel Skripkin
2021-09-28 10:55           ` Dan Carpenter
2021-09-28 11:04             ` Pavel Skripkin
2021-09-28 10:59           ` Dan Carpenter
2021-09-28 11:06             ` Pavel Skripkin
2021-09-28 11:09               ` Pavel Skripkin
2021-09-28 11:30                 ` Dan Carpenter
2021-09-28 11:45                   ` Pavel Skripkin
2021-09-28 12:23                     ` Dan Carpenter
2021-09-28 12:58                   ` Russell King (Oracle)
2021-09-28 13:52                     ` Dan Carpenter
2021-09-28 15:41                       ` Russell King (Oracle) [this message]
2021-09-28 15:48                         ` Dongliang Mu
2021-09-29  2:05                           ` Xu, Yanfei
2021-09-28 13:11 ` Russell King (Oracle)
2021-09-29 21:31 ` Denis Efremov

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=YVM3sFBIHzEnshvd@shell.armlinux.org.uk \
    --to=linux@armlinux.org.uk \
    --cc=andrew@lunn.ch \
    --cc=bgolaszewski@baylibre.com \
    --cc=dan.carpenter@oracle.com \
    --cc=davem@davemloft.net \
    --cc=hkallweit1@gmail.com \
    --cc=kuba@kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=mudongliangabcd@gmail.com \
    --cc=netdev@vger.kernel.org \
    --cc=p.zabel@pengutronix.de \
    --cc=paskripkin@gmail.com \
    --cc=syzbot+398e7dc692ddbbb4cfec@syzkaller.appspotmail.com \
    --cc=yanfei.xu@windriver.com \
    /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.