From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mx0a-0031df01.pphosted.com (mx0a-0031df01.pphosted.com [205.220.168.131]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 5940E32FA1B for ; Sat, 18 Jul 2026 23:40:38 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=205.220.168.131 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784418039; cv=none; b=tarzOFvKWGMUkNF4m0lEcANbBX6TNJMkmJKqdwNFqVK1pFXwrGWN79u/YXjfT5EKGNLFpXO7tT6rLujj5XKkNV3Y93fPa8KynLwbn5oIwYVbfIeoSiD14rBEkiVcn87l/60wzHq0WBfHg8bIfNLGNnUg5Zij+yAJniVR3V3O/fE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784418039; c=relaxed/simple; bh=XWCs4fUBo6gGQ1M2CVgFrj56MJznDKoZZ3l/K7qUBiA=; h=Date:From:To:Cc:Subject:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=KzxWzOC/847Zk7mHODci8g5XUKgkNrMh1PUoLtMORykv8jikNSF+1LNsdU3YDXYiYa4B/Wo9ij4/5rLQFlGlcp+p3CdtSUqJeT0Mvs7vEBL3YENzyC/zUPMaSyC3zXzBF5HNj6p62fbaI2nNrPjcjuPE5TtEgMiXo372mphfYT8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=oss.qualcomm.com; spf=pass smtp.mailfrom=oss.qualcomm.com; dkim=pass (2048-bit key) header.d=qualcomm.com header.i=@qualcomm.com header.b=eqeFNGzO; dkim=pass (2048-bit key) header.d=oss.qualcomm.com header.i=@oss.qualcomm.com header.b=Djgrl4pZ; arc=none smtp.client-ip=205.220.168.131 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=oss.qualcomm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=oss.qualcomm.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=qualcomm.com header.i=@qualcomm.com header.b="eqeFNGzO"; dkim=pass (2048-bit key) header.d=oss.qualcomm.com header.i=@oss.qualcomm.com header.b="Djgrl4pZ" Received: from pps.filterd (m0279862.ppops.net [127.0.0.1]) by mx0a-0031df01.pphosted.com (8.18.1.11/8.18.1.11) with ESMTP id 66IN212q1780693 for ; Sat, 18 Jul 2026 23:40:37 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=qualcomm.com; h= cc:content-transfer-encoding:content-type:date:from:in-reply-to :message-id:mime-version:references:subject:to; s=qcppdkim1; bh= Z3Q9taMjWV9GchlGB3+zBzhpobDtgh7Q1RKR4fp9cao=; b=eqeFNGzOzq/LuXAC rrVczsovsIm/nfjblLpCpc22YiURUUBI5y3tPn0mnzSpcy/r89538s+VpcWdvE04 7Wv9HcU1dXRknHJfqImE6MUJN2i0YMQS7BU/eiILFbzjrvbq2fG2n/qge8+FEYwF ikOaOgM9Fpm2rDPqAba2fqWRj5eYnBRUf0hmyYKPHkX2t3UA2GGfeX+jywd9VFZW rpgj0SVXtFpxWz4KDSJaxvl/WfJJcMjTXWxVkbsqhCteLvSaHVrX1IWz3Fkd2S8h 2DmnC4+ukJrdShJ26quDe3/iIbn0aMVWsN2DciWAHIErj3HQZ7A7RWkiN43WIK7N yNMb3g== Received: from mail-pl1-f197.google.com (mail-pl1-f197.google.com [209.85.214.197]) by mx0a-0031df01.pphosted.com (PPS) with ESMTPS id 4fg2bvsr7j-1 (version=TLSv1.3 cipher=TLS_AES_128_GCM_SHA256 bits=128 verify=NOT) for ; Sat, 18 Jul 2026 23:40:37 +0000 (GMT) Received: by mail-pl1-f197.google.com with SMTP id d9443c01a7336-2cee1ec30f2so78229845ad.3 for ; Sat, 18 Jul 2026 16:40:37 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oss.qualcomm.com; s=google; t=1784418037; x=1785022837; darn=vger.kernel.org; h=content-transfer-encoding:content-type:mime-version:references :in-reply-to:message-id:subject:cc:to:from:date:from:to:cc:subject :date:message-id:reply-to:content-type; bh=Z3Q9taMjWV9GchlGB3+zBzhpobDtgh7Q1RKR4fp9cao=; b=Djgrl4pZ6NnU040txIyuUrBcR9LZGGKh8f59IwgUYnOX7N+oAbnbTI3OOq8FHsEqEO Ijqe2/MtpQBeJWbOQ23Cwd1YlJYhBctKupnkGI9xUcp73FtpCAUfuSkizAKcjYIa/ayR TBwdSLj2RFCX8Y6Kvt9GyMLfQjQ2Rp4g7EMr+VbbsENqdCePqRNdQBEFTlB/DZ2rVCAL RpQeet8EprQ7oOA6MSAKFjYHdsFum4/MjO+1MiC3evTYtgEf/MgP7vLgPSFshQZZsuUm qPsUnkyt0/58X5sIx+Vql9cuNmSMsfJ3V4UPbnBPW5jpnu8KgR8PA6gAnvLX92HA6Lj4 oW1Q== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1784418037; x=1785022837; h=content-transfer-encoding:content-type:mime-version:references :in-reply-to:message-id:subject:cc:to:from:date:x-gm-gg :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to :content-type; bh=Z3Q9taMjWV9GchlGB3+zBzhpobDtgh7Q1RKR4fp9cao=; b=L6neTsVlWJIToMTgAon3Y7lyNZp+JuBvUsTTETRvJKIUk9+mw3+zbmB7+BztBeUQts eDBBwNYUG2yqu8S0LA5Hp+fEpbgjt9ZFGYA2AFa5Q+gCr7fCW+EZKJX97wCCne7wvTGc U+oKXfgZxg88mswC63XFOQAKtpSke4qrqfhIeRJzcOdNzYvdXtNDVL1wev32ISu7l1nk oIOQbbjkbfgiJk2kZP6+Uf/Neyt3VsN7EMJmxVnstMbGamrd9E2NTZjJjGOoBBbcd77t cC5lnm5fJeemvpy/txZRkKMHObvlV3E1ERy+TpegyRnvOvF4CRQ/278nnHoXp1P972lI 7AhA== X-Forwarded-Encrypted: i=1; AHgh+RpT47QO9jVag6FAACgVmk+90AnplypbHg0arlaJXdk83hBhj185QHJEMaKtohWZlCiYoFa2TMoGLKQ=@vger.kernel.org X-Gm-Message-State: AOJu0Yzxy4NxRrD8OYfCzyn3oXLxUDUeZilrWZYW80RTk/Kec33bhzZ2 WUyp1qKde+Vm8NvQ98XjnRQxbbydz33W2v9P0UF0WUGA4EEErN2lM82khsGCAf94647Nq8iyEt+ vHT78ekLLfA6Ecs3QIkT3cjaAsuaV+o+Z0bc9SV8scXorVCzhyyawbkrhjwYoSjY= X-Gm-Gg: AfdE7ckqk/VDlJHkJh20HvSDPTTq2YqSwR9i22PBEECpz1NM9+reqx5CVxKiTgGEdSS kT6l7l1d9xzKlmxZ15DAzk6v2t+CnamWG7+Si/1HgTrVxr7YsmjEri+JTIVpyDRigoUDhzsedls eaBr58aOn5SRzeuIsPTUwIeA6Y3AAtI3/K3XCW5qmkS+Kkhq/02ZIOvtpq8qkdcOjzV12WsWPX6 TLHIkFDliZ+Yy/fmUm2hdYBk0doQGqZwoT0RLQN5C6uZfdTfEayzOiG+MZwIr8yQTVG43LJWka7 kMKC7Qdno1LK0sJGSlbAYpciw4giKQdJpZRSRyBbNQaAEKdRxnRFVv5tsZ0Xntl5JgUdVH4ulyb /mWQdvp+dGe3A1Fjj X-Received: by 2002:a17:903:324e:b0:2ca:6514:9201 with SMTP id d9443c01a7336-2cf3486f1ffmr93265195ad.15.1784418036759; Sat, 18 Jul 2026 16:40:36 -0700 (PDT) X-Received: by 2002:a17:903:324e:b0:2ca:6514:9201 with SMTP id d9443c01a7336-2cf3486f1ffmr93264825ad.15.1784418036323; Sat, 18 Jul 2026 16:40:36 -0700 (PDT) Received: from jic23-huawei ([50.35.46.84]) by smtp.gmail.com with ESMTPSA id d9443c01a7336-2cf3448d9b0sm33136325ad.13.2026.07.18.16.40.33 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sat, 18 Jul 2026 16:40:35 -0700 (PDT) Date: Sun, 19 Jul 2026 00:40:29 +0100 From: Jonathan Cameron To: Rodrigo Alencar via B4 Relay Cc: rodrigo.alencar@analog.com, Michael Auchter , linux@analog.com, linux-iio@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-hardening@vger.kernel.org, Michael Hennerich , David Lechner , Andy Shevchenko , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Philipp Zabel , Kees Cook , "Gustavo A. R. Silva" , sashiko-bot@kernel.org Subject: Re: [PATCH v8 1/8] iio: dac: ad5696: properly check i2c_transfer() return value Message-ID: <20260719002355.4a818026@jic23-huawei> In-Reply-To: <20260716-ad5686-new-features-v8-1-ebb0051af5e5@analog.com> References: <20260716-ad5686-new-features-v8-0-ebb0051af5e5@analog.com> <20260716-ad5686-new-features-v8-1-ebb0051af5e5@analog.com> X-Mailer: Claws Mail 4.4.0 (GTK 3.24.52; x86_64-pc-linux-gnu) Precedence: bulk X-Mailing-List: linux-iio@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Proofpoint-GUID: EqZCtAEiVHJ3GPeHLI4e-Wym2YrDG458 X-Authority-Analysis: v=2.4 cv=EcH4hvmC c=1 sm=1 tr=0 ts=6a5c0ef5 cx=c_pps a=cmESyDAEBpBGqyK7t0alAg==:117 a=qC1CW/w66vtJz1P9yTJxNA==:17 a=kj9zAlcOel0A:10 a=RAioF0-LDSMA:10 a=s4-Qcg_JpJYA:10 a=VkNPw1HP01LnGYTKEx00:22 a=u7WPNUs3qKkmUXheDGA7:22 a=_K5XuSEh1TEqbUxoQ0s3:22 a=VwQbUJbxAAAA:8 a=gAnH3GRIAAAA:8 a=IpJZQVW2AAAA:8 a=eCasKaYD3dZQZqGzH0wA:9 a=CjuIK1q_8ugA:10 a=1OuFwYUASf3TG4hYMiVC:22 a=IawgGOuG5U0WyFbmm1f5:22 X-Proofpoint-Spam-Details-Enc: AW1haW4tMjYwNzE4MDI0OCBTYWx0ZWRfX9NVdvrR60Jcw UISdrs9Dzmw7gywLv8c0ZShFRbg58NcD/b29e0sPibduBX5jR/gD//GNQj9SVbUq1IW8pgNGHTV WGmlAbTaOqgh7jqZes9xdd1xL8LLg4+3fxFv5XxTjTe4dlcpp2deBFGLELLAJjmWF7YvdQev/BZ A0LAqRw+xaK5/ThWpu/7WAUEdAPWieShQXCugeoevEwUEvhQJ96b2lPxHGwnAuRYyFCIBB+jjnY ljmfLncVp9f2mbBhUsQvnpqgWOqLRgxWRE/KPp5MBfbBqiuSkeT/HyOA7Kz0wP6ORjpZPAMHVuf D5qtNkyfgm1MdQfMxAz4x9/zE1q1IfeGv4fBJ/moPpCbp767GyaA6wq3p6GZAo2GWNIIhRdAEIu tz8C0HX8lSdWCKIqZWO20A/RLjyUMjlFkig5kN7vpynq44I9YyktF2rDy1qoSvOLU/HUccFkg46 J8iDN0DkiKf9qzuLiKQ== X-Proofpoint-ORIG-GUID: EqZCtAEiVHJ3GPeHLI4e-Wym2YrDG458 X-Proofpoint-Spam-Info: AW1haW4tMjYwNzE4MDI0OCBTYWx0ZWRfX3fX7J8Hq267K Myk/nonOsg6XSs/o//xVlTc1C+a8kWkiFpuKd3VzwKX1NvK/m1SO3CE4+6aw4/fhxaJhIEdDtaU bz8RC7z3VvBd6OBR5/rw/9YaD0JP2/w= X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1143,Hydra:6.1.134,FMLib:17.12.100.49 definitions=2026-07-18_07,2026-07-17_01,2025-10-01_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 lowpriorityscore=0 suspectscore=0 bulkscore=0 clxscore=1015 impostorscore=0 phishscore=0 adultscore=0 malwarescore=0 priorityscore=1501 spamscore=0 classifier=typeunknown authscore=0 authtc= authcc= route=outbound adjust=0 reason=mlx scancount=1 engine=8.22.0-2606150000 definitions=main-2607180248 On Thu, 16 Jul 2026 13:14:17 +0100 Rodrigo Alencar via B4 Relay wrote: > From: Rodrigo Alencar > > Verify that the expected number of i2c messages were transferred when > ad5686_i2c_read() is called. This issue exists since the support for I2C > devices was first introduced. > > Fixes: 4177381b4401 ("iio:dac:ad5686: Add AD5671R/75R/94/94R/95R/96/96R support") > Reported-by: sashiko-bot@kernel.org > Closes: https://lore.kernel.org/all/20260705114746.1485F1F000E9@smtp.kernel.org/ > Reviewed-by: David Lechner > Signed-off-by: Rodrigo Alencar Let's hold off on this for now. Whilst it is technically correct today I'm looking into ensuring that we never need this. The only error case today is actually returning 0 which in practice is an error. > --- > drivers/iio/dac/ad5696-i2c.c | 5 ++++- > 1 file changed, 4 insertions(+), 1 deletion(-) > > diff --git a/drivers/iio/dac/ad5696-i2c.c b/drivers/iio/dac/ad5696-i2c.c > index 279309329b64..551b200bfe14 100644 > --- a/drivers/iio/dac/ad5696-i2c.c > +++ b/drivers/iio/dac/ad5696-i2c.c > @@ -7,6 +7,7 @@ > * Copyright 2018 Analog Devices Inc. > */ > > +#include > #include > #include > #include > @@ -39,9 +40,11 @@ static int ad5686_i2c_read(struct ad5686_state *st, u8 addr) > AD5686_ADDR(addr) | > 0x00); > > - ret = i2c_transfer(i2c->adapter, msg, 2); > + ret = i2c_transfer(i2c->adapter, msg, ARRAY_SIZE(msg)); > if (ret < 0) > return ret; > + if (ret != ARRAY_SIZE(msg)) > + return -EIO; > > return be16_to_cpu(st->data[0].d16); > } >