From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1792655438; b=pmhzEqy8nTkzX01gw7jIFxquZwyVsm5irfxQbZ1nFPmRkJsFqRE+1VfhJ89wW2QyvxLj FmKqdf2BaX/fq/eBFbVaRL30D026kw5Co+rYAFbKWJf+b+3LkIS0irKHgIWh9ZiR7MVz5 QekoZZzlo6K3KTvcW7gF9ZEshZgsVRxEveH0o7aw64Nitel92Jgt79+RSxzkZEJsF7BcK EfZ6H+Cmnnv2w5h/vnjsRBWaDuHzX6xW4pk81daVrY1ppQ3MSH1RIRjjy81KdoMPfnpsp pewfFLeEn2AxyXR0AXrUu7UxPOai80Yf4x/qtULPXYQMqo3h6xDd220hnjH5uDIPaTw== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1792655438; h=Received:DKIM-Signature:Message-ID:From:Subject:Reply-To:To:Cc: In-Reply-To:References:Content-Type:Content-Transfer-Encoding:Date; bh=lpq0JLv4H8/4NS5eNM3NmH1vLR960Eo/4fQi30abF5Y=; b=tzyI+XnPGYd7PTmsAjemKujicsSw/ECZ7EQX3toUYmxX4ib2OYmEJM98MbNL014Z0pki fKPbSydBMzN+em07PGb/oyB9H8Ap1asY+9gBRhHH26PBtQjR19/MrT/c4iQ3wZ66SG5kf XIpMeSwfmldF7TMltv6Hz0L6DGJ2E95rSon2pg4SaiDjb60jAipAXo9TtLVeyrYtoevag qjdYNbTHIF0cmXT/eVbNlJHNKki2k0lPvVcxard6ZI1nSuxZc+kUCa0QluPd6Fvt1ulYq a/8xwBqyVF5tipsV43hGX2pL1kj1LnSWQM1mEj9N5zjYcXgHB1ZFOn0HXX4/y3rNmbQ== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=P1CcAG+E; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id A159D606A320 for ; Thu, 22 Oct 2026 07:50:38 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key, unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=P1CcAG+E Received: by smtp.kernel.org (Postfix) with ESMTPSA id 628401F000C8; Thu, 22 Oct 2026 07:50:38 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1792655438; bh=lpq0JLv4H8/4NS5eNM3NmH1vLR960Eo/4fQi30abF5Y=; h=From:Subject:Reply-To:To:Cc:In-Reply-To:References:Date; b=P1CcAG+E6B7KKXp2owbcvgyWEQeu8v7cZ2gesCcN3zCALSedUyvOoegLjQh3FXlGN ht7oX+oLarqNnQnFQs3jKx15SjUCccQvJRLTQ4kkSe/hOnyvjzde4XdvAR7T1Ct5Hk gdfgtMXxCC46+jtE7fYt+ASsQEg2JZ3CvC+Rj3aadbTrIcw58WgqRh/yOojY0ynrxw 7p3L8EDFJhL+SutWRcW63agBtRwKBC435Sx8/9ISRhVPMR7veLAvEU686VoTiOvKLC col8Ik8YYdxSpiHAap8TUdBdzBX1okKzP3TKlC2zwoLkNYbD0NYAHYcvUH80w8yyEE NOsUD5thf4d/g== Message-ID: From: sashiko-bot@kernel.org Subject: Re: [PATCH net v4 3/7] virtio_net: parse tunnel csum_start little-endian Reply-To: sashiko-reviews@lists.linux.dev To: "Michael S. Tsirkin" Cc: virtualization@lists.linux.dev, "Eugenio Perez" In-Reply-To: <421e7ebb8173ab919c2b90b945aaed462145583d.1792565282.git.mst@redhat.com> References: <421e7ebb8173ab919c2b90b945aaed462145583d.1792565282.git.mst@redhat.com> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Date: Thu, 22 Oct 2026 07:50:38 +0000 X-Mailing-List: virtualization@lists.linux.dev List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list > All tunnel related virtio features are > 32, so none of this > functionality can be enabled on legacy mixed-endian device. >=20 > Accordingly, all tunnel header fields, csum_start included, are > little-endian. >=20 > The nested virtio net header import parses csum_start that way, but the > inner transport offset is parsed with the endianness specified by the > interface. >=20 > If tun is misconfigured to legacy big-endian mode while the tunnel > features are enabled, the two parses of this field disagree, and the > value stored in skb->inner_transport_header - which is only > bounds-checked from below - can point past the end of the packet, where > GSO segmentation later dereferences it. >=20 > To fix, parse the field little-endian in both places. >=20 > Fixes: a2fb4bc4e2a6 ("net: implement virtio helpers to handle UDP GSO tun= neling.") > Cc: Paolo Abeni > Signed-off-by: Michael S. Tsirkin Sashiko has reviewed this patch and found no issues. --=20 Sashiko AI review =C2=B7 https://sashiko.dev/#/patchset/cover.v4.git.mst@re= dhat.com?part=3D3