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[35.245.46.111]) by smtp.gmail.com with ESMTPSA id a1e0cc1a2514c-990d0e0ba56sm3638029241.1.2026.10.21.09.08.52 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 21 Oct 2026 09:08:52 -0700 (PDT) Date: Wed, 21 Oct 2026 12:08:52 -0400 From: Willem de Bruijn To: "Michael S. Tsirkin" , linux-kernel@vger.kernel.org Cc: Willem de Bruijn , Chris Arges , =?UTF-8?B?QmrDtnJuIFTDtnBlbA==?= , Phil Sutter , Jason Wang , =?UTF-8?B?RXVnZW5pbyBQw6lyZXo=?= , Xuan Zhuo , Andrew Lunn , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , netdev@vger.kernel.org, virtualization@lists.linux.dev, Max Krasnyansky , Rusty Russell , Richard Weinberger , Anton Ivanov , Johannes Berg , linux-um@lists.infradead.org Message-ID: In-Reply-To: <26741a9a64c28e8de6d13e04972d296d89e1c95d.1792565282.git.mst@redhat.com> References: <26741a9a64c28e8de6d13e04972d296d89e1c95d.1792565282.git.mst@redhat.com> Subject: Re: [PATCH net v4 2/7] um: vector: trim skbs before verifying the header X-Mailing-List: virtualization@lists.linux.dev List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Michael S. Tsirkin wrote: > The vector receive path over-allocates the skb and only trims it > to the received length after the transport header is verified. > > A follow up patch will complete the packet checksum in software within > virtio_net_hdr_to_skb so we need the packet trimmed (otherwise the > checksum would be computed incorrectly over the unreceived tail of the > buffer). > > Trim first, so the import sees the packet as it was received. > > Signed-off-by: Michael S. Tsirkin Reviewed-by: Willem de Bruijn