From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-qk1-f170.google.com (mail-qk1-f170.google.com [209.85.222.170]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id E18F519E998; Tue, 25 Feb 2025 18:24:53 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.222.170 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1740507895; cv=none; b=jsWN3U8gxm+kkcQm9DwiVhxB0uWM4+7Qeo5qtIG9dxJqlG6TAS0ZODe0D/qoz3Vi8GQUeFqLGT22GvMWMgnw+0aPYWPeEi6DQn2ldgvm6I6U+ELTWiONxxDeUYeSnSescEFDVnERg11YAri+sg2yZnJ426rpJGqC/EwVTN3L72o= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1740507895; c=relaxed/simple; bh=e12//0ouSuYLnVYPUmLDp7+6wElM0flmFydsFm2XJB0=; h=Date:From:To:Cc:Message-ID:In-Reply-To:References:Subject: Mime-Version:Content-Type; b=hUUd2+hUgBMKXqlS52REur/RlOAOqNl+LusF2aV1ud1dJ7qJ+oUQuuwEGME+JBzEAlYszX6v4xLNx5riWjEganexhR1U1XID1ZHIMjBljUASAl678LTf1T7imgEZwNQm61x22fcBwDzxfBf7l9IVZvtnJ+AjN3m+X9cnQelOHlA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com; spf=pass smtp.mailfrom=gmail.com; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b=c6JbI9ua; arc=none smtp.client-ip=209.85.222.170 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="c6JbI9ua" Received: by mail-qk1-f170.google.com with SMTP id af79cd13be357-7c0893f9aa6so536043785a.1; Tue, 25 Feb 2025 10:24:53 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1740507893; x=1741112693; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:subject:references :in-reply-to:message-id:cc:to:from:date:from:to:cc:subject:date :message-id:reply-to; bh=0IN/wgdM/wrAvot6cEOXlKkAGhjZU8WUV09Vtdsf31A=; b=c6JbI9ua2p+yguKTnsQTJIll2cOZALrC9flTAvd9hT61Y9FK6fc4mqYekP+8JPs1Er q2AIz1MkE8kG1pWMqbJO+jzgS6x557F/MAN6KcpxzOWdUFP/5aEhedJdUYJcZWuLrHhg 6Hi+GewAEitXcy2WxzK0KlsnlYLy9MH3H6bi1DzS0t0r3eBCg/8ZRE57pMfEjstLy/OG 5/bVutjhEHPDGam7zXVexCa5edBZEWI6aOOTvRuvCXy/r2be9hOY8LTrToPP/ndW+aJa Z48F8Gs/zj9H46eWbxsOP2jyQfqe4VldFkozVmFwafd8fZK8quazRSHAV0Xgq05rLK5F lAEw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1740507893; x=1741112693; h=content-transfer-encoding:mime-version:subject:references :in-reply-to:message-id:cc:to:from:date:x-gm-message-state:from:to :cc:subject:date:message-id:reply-to; bh=0IN/wgdM/wrAvot6cEOXlKkAGhjZU8WUV09Vtdsf31A=; b=isV4E2Z4F+gcbZW3xDBh+0ThSIrOd4iJjskox/SmXD+8ts4slqHFiFo4rw19G3P4QV uG3CU/pB+7L7QxlQMdL9D3tm1OgyYxhyUc66KgDqU9OFbllT/VlQydOYS1wgC22wqGgb An7D2JjBLePcwH686ZTluVlUxWtZ07Xrdeo+IQTEpuc9gaTpeB7TRMZRq1SFEfADUeGX JlmZDy9AlujUot6LCkuGgxJ5zJhOsjdIe1mfAuOzX6kSSY0qYKClTR3lDCxHFNZbX2V5 XvjUv4xgLYw14vrumHipWYKtnM1JUso12x6aZuWliAtseo+I4oxlfnGzxHOqTnfJkM0D vZrQ== X-Forwarded-Encrypted: i=1; AJvYcCUna2ahw/ydT11CM4/9aQMdJvO+noYhCNJyjyX/bQtMogpqKPHczwbcV9a78CojU/gfNprIcRHitP2fN59Y@vger.kernel.org, AJvYcCWEOkNQT48rH1lJMcLMn4SqBBlZRyO8qNt1F2yFmr0Xx+vZI31BTSKp9lw6XN60TAq29OiTr7Yg1eq7tGTwF4tU@vger.kernel.org, AJvYcCWNckhL/asMZDppNK0KVb6dujC08n1ouAUYE6xCWiIS3lAWiMT5e2vSy7FLLYRkNwaxXww=@vger.kernel.org, AJvYcCXFEKK8S5OtV0/ZRPzFPuNK0tZ1EJgHddRTdIBrAQI6+HuN8JqHQO5vKEHDfHnmDH4L7QCgxix3@vger.kernel.org X-Gm-Message-State: AOJu0Yw15cYT4PD3kygaKxjXVVrGml0/HhJLyBaKKAwPpka1fx05gt95 RjTnIPehFTjwxlMJXI6Oz8cgzrFNueRwQTNFn287n5YRUC99PvdN X-Gm-Gg: ASbGncsKrcxNmdvz9Yl9OFkmDtQPmBBKRowv6kqawcMD/DvApnPGuYn+iXa64sJRGQM Kfb4brRCqHl1439CwjmF1jEUrgx7uiErk5fm/q/wqBHvwAHWK6ZQjmKxE77Do/ebFnwCAzVGQ4P fjF6ZHUNTc+ldMkHPh40dZgnValGV0g1J9/VzHuSvipfu3+BiFbtY5X569sylltkSunBarP3AGE HSsxq8eCtrYODOKPcA1R2SX0NPn1JCJYyflYNpNWkdrZWSEMhozUurWcegwfq2HLlpxgh6VMIhE Ke9vmdJbpHt8CsxOb9K+r5BTzSWWx8N0AgpmAyXywI+EgHo3cj2sZDEpvdXwakbKv/jIp1LD64m sFIk= X-Google-Smtp-Source: AGHT+IE0uqadArm2YyxmryYO6uV+0djUKpmQp6U0wfVS3CUcxbQVu8M6YUav4D1eNxARKeUZWioYCA== X-Received: by 2002:a05:620a:4148:b0:7c0:9f12:2b90 with SMTP id af79cd13be357-7c0cf8aea46mr2519889085a.6.1740507892562; Tue, 25 Feb 2025 10:24:52 -0800 (PST) Received: from localhost (234.207.85.34.bc.googleusercontent.com. [34.85.207.234]) by smtp.gmail.com with ESMTPSA id af79cd13be357-7c23c329847sm136097285a.74.2025.02.25.10.24.51 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 25 Feb 2025 10:24:51 -0800 (PST) Date: Tue, 25 Feb 2025 13:24:51 -0500 From: Willem de Bruijn To: Marcus Wichelmann , netdev@vger.kernel.org, linux-kernel@vger.kernel.org, bpf@vger.kernel.org, linux-kselftest@vger.kernel.org Cc: willemdebruijn.kernel@gmail.com, jasowang@redhat.com, andrew+netdev@lunn.ch, davem@davemloft.net, edumazet@google.com, kuba@kernel.org, pabeni@redhat.com, andrii@kernel.org, eddyz87@gmail.com, mykolal@fb.com, ast@kernel.org, daniel@iogearbox.net, martin.lau@linux.dev, song@kernel.org, yonghong.song@linux.dev, john.fastabend@gmail.com, kpsingh@kernel.org, sdf@fomichev.me, haoluo@google.com, jolsa@kernel.org, shuah@kernel.org, hawk@kernel.org, marcus.wichelmann@hetzner-cloud.de Message-ID: <67be0af39dbf7_25ccfc2943c@willemb.c.googlers.com.notmuch> In-Reply-To: <20250224152909.3911544-7-marcus.wichelmann@hetzner-cloud.de> References: <20250224152909.3911544-1-marcus.wichelmann@hetzner-cloud.de> <20250224152909.3911544-7-marcus.wichelmann@hetzner-cloud.de> Subject: Re: [PATCH bpf-next v3 6/6] selftests/bpf: fix file descriptor assertion in open_tuntap helper Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Marcus Wichelmann wrote: > The open_tuntap helper function uses open() to get a file descriptor for > /dev/net/tun. > > The open(2) manpage writes this about its return value: > > On success, open(), openat(), and creat() return the new file > descriptor (a nonnegative integer). On error, -1 is returned and > errno is set to indicate the error. > > This means that the fd > 0 assertion in the open_tuntap helper is > incorrect and should rather check for fd >= 0. > > When running the BPF selftests locally, this incorrect assertion was not > an issue, but the BPF kernel-patches CI failed because of this: > > open_tuntap:FAIL:open(/dev/net/tun) unexpected open(/dev/net/tun): > actual 0 <= expected 0 > > Signed-off-by: Marcus Wichelmann Reviewed-by: Willem de Bruijn