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Miller" , Jakub Kicinski , netdev@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH net-next v2] net: dsa: avoid potential use-after-free error Message-ID: <20201120180149.wp4ehikbc2ngvwtf@skbuf> References: <20201119110906.25558-1-ceggers@arri.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20201119110906.25558-1-ceggers@arri.de> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Nov 19, 2020 at 12:09:06PM +0100, Christian Eggers wrote: > If dsa_switch_ops::port_txtstamp() returns false, clone will be freed > immediately. Shouldn't store a pointer to freed memory. > > Signed-off-by: Christian Eggers > Fixes: 146d442c2357 ("net: dsa: Keep a pointer to the skb clone for TX timestamping") > --- IMO this is one of the cases to which the following from Documentation/process/stable-kernel-rules.rst does not apply: - It must fix a real bug that bothers people (not a, "This could be a problem..." type thing). Therefore, specifying "net-next" as the target tree here as opposed to "net" is the correct choice. Reviewed-by: Vladimir Oltean Tested-by: Vladimir Oltean