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Miller" , Jakub Kicinski , Paolo Abeni , Simon Horman , "moderated list:CAKE QDISC" , "open list:TC subsystem" , open list Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Message-ID-Hash: GGVNLIRMCTW26QSIYP57WSBW7UDFC62E X-Message-ID-Hash: GGVNLIRMCTW26QSIYP57WSBW7UDFC62E X-MailFrom: edumazet@google.com X-Mailman-Rule-Misses: dmarc-mitigation; no-senders; approved; loop; banned-address; emergency; member-moderation; nonmember-moderation; administrivia; implicit-dest; max-recipients; max-size; news-moderation; no-subject; digests; suspicious-header X-Mailman-Version: 3.3.10 Precedence: list Subject: [Cake] Re: [PATCH] net/sched: cake: reject overhead values that underflow length List-Id: Cake - FQ_codel the next generation Archived-At: List-Archive: List-Help: List-Owner: List-Post: List-Subscribe: List-Unsubscribe: On Mon, Jun 8, 2026 at 5:06=E2=80=AFPM Samuel Moelius wrote: > > CAKE accepts overhead values that can make adjusted packet length > arithmetic underflow. A negative effective length can wrap through > unsigned arithmetic and become a large value. > > Such configurations make rate accounting depend on integer wraparound > rather than on the packet size userspace intended to model. > > Validate overhead settings before using them in adjusted length > calculations. > > Assisted-by: Codex:gpt-5.5-cyber-preview > Signed-off-by: Samuel Moelius > --- We need a Fixes: tag pw-bot: cr