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=1793824293; b=DyOWQzW/L9NxvDlrxKVORxD5z8gNXXpr1f2S9y6Hb3MYTBGjeYwpUPPl7JdXGigvPu3X YeSyCBHRC4YMpCYwh3IpJTgCqPaJc71yn1PNWLgNhtsonTodmdqS9a6+w98hkFX1aXn0U jvFhCACCWLyaQVrY+MiKcEwyVEM826ZUC/QIC/I8h1xzgn92zQe8lP+5TQhUWYIpJA6I7 Vw6ZfM9NUav5Fppcmog9kXWWewJCfcwJY9RYGzb157LzYNAvLfgKuY8HAiUVHpnb8wKuU eGdTy8CBt+yrGQKalSm7SyUTXBssziz5GQ/85gC8ISdl3FmWc/ztODR4u+crmdVleHA== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1793824293; h=Received:DKIM-Signature:Message-ID:From:Subject:Reply-To:To:Cc: In-Reply-To:References:Content-Type:Content-Transfer-Encoding:Date; bh=HzectLEwg6SVq0XizgONNFPKbMsGlFL+pegfzfsgI9I=; b=KJoi9fhzJ5IXYvQvOceziAtTLVauOOQdJ75XSwamXp5L6iwLImPMQcQKifemiNvrmSDv KdIuVNLX4gCXWRD1yRjfIkJDyYsnqAKJRdZUES7Y5Xh9vlC6Oe/98zMPFyqzOYnNtI82Q G2RCe0ZR//L3i+Lw6dAVhyyQyIMQOaP1IgVcX0I51EDxi79GuCJkuAp+Hhy26psCuVVeu PYHYvkQn1fGT7mCvBnpbTNtLuJhnULKCEPsggzzxrNOk2q/ai09Alg4s0cSG7GTMh5Ge8 QulKf1mGCdqEhMgtiTh2KV9PHhFlDj+FvSOQSGFIGpjPfx+RMV6MvcuWwqqba73ivBw== 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=IByVjCcX; 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 8E7086082BED for ; Wed, 4 Nov 2026 20:31:33 +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=IByVjCcX Received: by smtp.kernel.org (Postfix) with ESMTPSA id 046771F00919; Wed, 4 Nov 2026 20:31:32 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1793824293; bh=HzectLEwg6SVq0XizgONNFPKbMsGlFL+pegfzfsgI9I=; h=From:Subject:Reply-To:To:Cc:In-Reply-To:References:Date; b=IByVjCcXXm6FaqjvPAqb/u3QEsyZ/kOgubihjG7syKCHWgiUR1nVIMwOlEskIJrOE Xknm7FwGsbXjhJwzOYDhchcNUGQvRjzSDRmbwO0m6YXpsvy9kl1neE3pCCCjbrFW0q pH+31h/7uQKnUgSJgLl00KidvLCOMWQy5Tb9lXdJZ0rO3VMTOd6CJ26fowGdRua4Pv B38dAL0ZGUI7hPSkSbc9K1R51DDJOawjtQAdL95pnk77GnHJu1WyeKarR9Zl2c8AWq C5CvaSRdkGdlsUC8FK7sKl7UVN1BkVdmieLYoxTy5PofjRbsqhjzgSKLuziysJ5nId uP1Dws3f9uOGw== Message-ID: From: sashiko-bot@kernel.org Subject: Re: [PATCH net 2/3] selftests: net: tuntap: fix UDP checksum length in build_udp_packet_csum() Reply-To: sashiko-reviews@lists.linux.dev To: "Eric Dumazet" Cc: virtualization@lists.linux.dev, "Michael S. Tsirkin" , "Eugenio Perez" In-Reply-To: <20261103203113.550604-3-edumazet@kernel.org> References: <20261103203113.550604-1-edumazet@kernel.org> <20261103203113.550604-3-edumazet@kernel.org> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Date: Wed, 04 Nov 2026 20:31:32 +0000 X-Mailing-List: virtualization@lists.linux.dev List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list > build_udp_packet_csum() passes udph->len, which is in network byte > order, as the number of bytes to checksum. On little-endian hosts this > reads up to 64KB past the UDP header and computes a wrong checksum. >=20 > Existing callers did not crash only because they use packet buffers > of MAX_VNET_TUNNEL_PACKET_SZ bytes. >=20 > Use ntohs(udph->len), as tap.c does in its own build_udp_packet(). >=20 > Fixes: a942fcd72e97 ("selftest: tun: Introduce tuntap_helpers.h header fo= r TUN/TAP testing") > Signed-off-by: Eric Dumazet Sashiko has reviewed this patch and found no issues. --=20 Sashiko AI review =C2=B7 https://sashiko.dev/#/patchset/20261103203113.5506= 04-1-edumazet@kernel.org?part=3D2