Received-SPF: pass (google.com: domain of linux-kernel+bounces-52225-linux.lists.archive=gmail.com@vger.kernel.org designates 139.178.88.99 as permitted sender) client-ip=139.178.88.99;
Date: Mon, 5 Feb 2024 08:50:07 +0000
From: Lee Jones <lee@kernel.org>
To: Andrew Lunn <andrew@lunn.ch>
Cc: Christian Marangi <ansuelsmth@gmail.com>, Pavel Machek <pavel@ucw.cz>,
	"David S. Miller" <davem@davemloft.net>,
	Jakub Kicinski <kuba@kernel.org>,
	Heiner Kallweit <hkallweit1@gmail.com>,
	Daniel Golle <daniel@makrotopia.org>,
	Li Zetao <lizetao1@huawei.com>, linux-leds@vger.kernel.org,
	linux-kernel@vger.kernel.org, stable@vger.kernel.org
Subject: Re: [PATCH] leds: trigger: netdev: Fix kernel panic on interface
 rename trig notify
Message-ID: <20240205085007.GA19855@google.com>
References: <20240203235413.1146-1-ansuelsmth@gmail.com>
 <8d51f09b-e6d2-4ee1-9e7d-b545d561798a@lunn.ch>
Precedence: bulk
MIME-Version: 1.0
Content-Type: text/plain; charset=utf-8
Content-Disposition: inline
Content-Transfer-Encoding: 8bit
In-Reply-To: <8d51f09b-e6d2-4ee1-9e7d-b545d561798a@lunn.ch>

On Sun, 04 Feb 2024, Andrew Lunn wrote:

> On Sun, Feb 04, 2024 at 12:54:01AM +0100, Christian Marangi wrote:
> > Commit d5e01266e7f5 ("leds: trigger: netdev: add additional specific link
> > speed mode") in the various changes, reworked the way to set the LINKUP
> > mode in commit cee4bd16c319 ("leds: trigger: netdev: Recheck
> > NETDEV_LED_MODE_LINKUP on dev rename") and moved it to a generic function.
> > 
> > This changed the logic where, in the previous implementation the dev
> > from the trigger event was used to check if the carrier was ok, but in
> > the new implementation with the generic function, the dev in
> > trigger_data is used instead.
> > 
> > This is problematic and cause a possible kernel panic due to the fact
> > that the dev in the trigger_data still reference the old one as the
> > new one (passed from the trigger event) still has to be hold and saved
> > in the trigger_data struct (done in the NETDEV_REGISTER case).
> > 
> > On calling of get_device_state(), an invalid net_dev is used and this
> > cause a kernel panic.
> > 
> > To handle this correctly, move the call to get_device_state() after the
> > new net_dev is correctly set in trigger_data (in the NETDEV_REGISTER
> > case) and correctly parse the new dev.
> > 
> > Fixes: d5e01266e7f5 ("leds: trigger: netdev: add additional specific link speed mode")
> > Cc: stable@vger.kernel.org
> > Signed-off-by: Christian Marangi <ansuelsmth@gmail.com>
> 
> This should have 'net' in the subject line, to indicate which tree its
> for.

No, it shouldn't.

Contributors aren't obliged to know anything about merging strategies.

Why does this need to go in via net?

> Otherwise:
> 
> Reviewed-by: Andrew Lunn <andrew@lunn.ch>

Thanks.  Always very useful.

-- 
Lee Jones [李琼斯]