From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-ed1-f53.google.com (mail-ed1-f53.google.com [209.85.208.53]) (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 66B5518E20 for ; Mon, 30 Jun 2025 07:48:48 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.208.53 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1751269730; cv=none; b=IxTfl9MplDXORCgC4/g+WQYFFSJS3bxL4aXkeoPWHVKl+wnAvIOR/CKaJECdjRThP5Gh+5+OmbqfRdzXfw5kA2pSl2GYyUnmUzfXrbZE4dzfE6NhO8SrsJiIFsXcECased0jISNTFg+BXx6Jjh93/o8zANHUkuwjp9lEUhKNJMA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1751269730; c=relaxed/simple; bh=qf8NaywLRmWMHaEJuLsltQXouTMmM7A/UAbuopsgvUI=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=HeCX0o8FkfotnextPcBpdrMPKjsBGgVaYPNGd0nJoq5NotdjtQd7aYA1YLxaPhuxfUMYUPC8WfbmF0qdRfmUfMLGnkt6lzxuLIP2/Tkdc9RMH00nh5kZmIos0eDrBlJqd0a+HIFMnWiR+T9HMn90n39gPwPy/DIEsQbwWRY7pgs= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=mandelbit.com; spf=pass smtp.mailfrom=mandelbit.com; dkim=pass (2048-bit key) header.d=mandelbit.com header.i=@mandelbit.com header.b=G68ILadV; arc=none smtp.client-ip=209.85.208.53 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=mandelbit.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=mandelbit.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=mandelbit.com header.i=@mandelbit.com header.b="G68ILadV" Received: by mail-ed1-f53.google.com with SMTP id 4fb4d7f45d1cf-60702d77c60so8289845a12.3 for ; Mon, 30 Jun 2025 00:48:48 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=mandelbit.com; s=google; t=1751269727; x=1751874527; darn=vger.kernel.org; h=content-transfer-encoding:in-reply-to:organization:autocrypt:from :content-language:references:cc:to:subject:user-agent:mime-version :date:message-id:from:to:cc:subject:date:message-id:reply-to; bh=tZ+BSaUYjMYZPFRc5ahI5f+VB6TZxnMY7+aM/BHB0gk=; b=G68ILadVVZwyr8ugTC0v7wFBWa/DeA6lLn6W1yFZvySa5nJebBnTJnMtGqUCqytDtJ y0nO5dNZ6CFAzLmez2Thsh6Xx6VvUEE0MUdwDwrYkUQYCv5b0gximxXfnCsI28U/6+g1 gnp0sml0albInrW9cB0UvHSHJT3YhXkSp0rEX3thEYTFNk0XEOeS/DeUgVLmx4jJi12h pRQrkPfwb5xpMl3iVdDeFKeA+qbOQaAG2RM6Fm7SfhORZuc9NE4pe/h42LD9rcVsy5Jw jWxPFiVun5aRzOs6iGdYPGx++f17kmtZNB3b6d3EmClXjvHImydMUmda4QzpoOtkVXtD 71JA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1751269727; x=1751874527; h=content-transfer-encoding:in-reply-to:organization:autocrypt:from :content-language:references:cc:to:subject:user-agent:mime-version :date:message-id:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=tZ+BSaUYjMYZPFRc5ahI5f+VB6TZxnMY7+aM/BHB0gk=; b=VC3rbnhl3V/Yxa379DcuJ9IbyD++XN3IWnLoUPQBhtJcmZ67kf9nNqHa5jUbzdymp6 yHI9g+O25XtRnsRFlSEJCJER+P9pAuu3niboweRoYKy2eNMz0yZ35552qYxUSvzxqZUA ll6FtAwVAcOf8QT+VV+BeE2nsjEBGv0tWxXFz8q+FprDm0WzyhV9Yx6Q1SxD96gBVT1D tkVKJc8nY1wmJIV1wc38PmIaSnj7zj0D6BZZ97hM2dS2pBf+qHiZiS3YuolvoAd6nUVY XEqTBMmJTVcVS9r+RQmXBByFddmVoHQBBksgXWOXjv5DBjvyZwfLP8bxxkOTtSWaUTHq bi4g== X-Forwarded-Encrypted: i=1; AJvYcCVZF8uLnoT2jD0MO98RzNsQPquUlnBLUn5b3MPKCeoCYYdlc8oDteZsTET5JILTpsr9+pYsWp23iNk2KSA=@vger.kernel.org X-Gm-Message-State: AOJu0YwCWtv1FrbgNQHMg5IsdZsZ3DkaWCKGt5jlvyJpuEd7EeeEFnMo PtHhnztBbEppBue7QC33ezzwYJJixDa3ggHJGRwvsjw643fswesKcsGVEUaJNU2k0o8= X-Gm-Gg: ASbGncsDKRiMpaDv3fiDXMymx22fuvXD5wUYvIzdH3Sf2Am6K4AmUmztuHv9VtB79VL FbtEwrZJbuffCeycN0EYh/OSYNgRIBLlyGZmuRiXPG2rjS8v96dbTTkuBwiamsn3v0BqVTn+a8V D2jl/eKleKgK0q8ETuEFDS6Q5EUSWDLD5MDvXvQfXLiWJZB3hMw9aBogb7onvz1qSm8s5ZCAVsd rogbQF6BmJ90OhyMdesPLlGx6TicpIOQpJdFmoVKoNl/mAtple5Nj9NOu+H8zbxMs4lxXLARXUi CWfd5tbk7wHpm+YW4Lzn0sJ2XjWIIvos9EGpU3icU12Ydj8UF7wCGJY1K2rCnCNbiQVykbcw9v1 sL9DVZ2R7cPAmDo6Cu1ZNd4Cy X-Google-Smtp-Source: AGHT+IFG8mxwherCyB+H+Ce/MDetYKrbqKrvuEJkbWn3WcmopojqghsC9D4gNWRWL3XhXfmKmOCezQ== X-Received: by 2002:a17:907:8691:b0:ae0:ade2:606b with SMTP id a640c23a62f3a-ae34fd8ecebmr1192187566b.19.1751269726337; Mon, 30 Jun 2025 00:48:46 -0700 (PDT) Received: from ?IPV6:2001:67c:2fbc:1:f5fc:eb97:a20:8b31? ([2001:67c:2fbc:1:f5fc:eb97:a20:8b31]) by smtp.gmail.com with ESMTPSA id a640c23a62f3a-ae35363b1c4sm623062966b.31.2025.06.30.00.48.45 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Mon, 30 Jun 2025 00:48:45 -0700 (PDT) Message-ID: <1c6f4024-be8a-4734-a724-f12b85a52ed7@mandelbit.com> Date: Mon, 30 Jun 2025 09:48:44 +0200 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH] spi: stm32: fix NULL check on pointer-to-pointer variable To: Clement LE GOFFIC , linux-spi@vger.kernel.org Cc: linux-stm32@st-md-mailman.stormreply.com, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, Alexandre Torgue , Maxime Coquelin , Mark Brown , Alain Volmat References: <20250628000227.22895-1-antonio@mandelbit.com> <1f49b8f3-44c9-43f3-a3bf-b931fb0726f4@foss.st.com> Content-Language: en-US From: Antonio Quartulli Autocrypt: addr=antonio@mandelbit.com; keydata= xsFNBFN3k+ABEADEvXdJZVUfqxGOKByfkExNpKzFzAwHYjhOb3MTlzSLlVKLRIHxe/Etj13I X6tcViNYiIiJxmeHAH7FUj/yAISW56lynAEt7OdkGpZf3HGXRQz1Xi0PWuUINa4QW+ipaKmv voR4b1wZQ9cZ787KLmu10VF1duHW/IewDx9GUQIzChqQVI3lSHRCo90Z/NQ75ZL/rbR3UHB+ EWLIh8Lz1cdE47VaVyX6f0yr3Itx0ZuyIWPrctlHwV5bUdA4JnyY3QvJh4yJPYh9I69HZWsj qplU2WxEfM6+OlaM9iKOUhVxjpkFXheD57EGdVkuG0YhizVF4p9MKGB42D70pfS3EiYdTaKf WzbiFUunOHLJ4hyAi75d4ugxU02DsUjw/0t0kfHtj2V0x1169Hp/NTW1jkqgPWtIsjn+dkde dG9mXk5QrvbpihgpcmNbtloSdkRZ02lsxkUzpG8U64X8WK6LuRz7BZ7p5t/WzaR/hCdOiQCG RNup2UTNDrZpWxpwadXMnJsyJcVX4BAKaWGsm5IQyXXBUdguHVa7To/JIBlhjlKackKWoBnI Ojl8VQhVLcD551iJ61w4aQH6bHxdTjz65MT2OrW/mFZbtIwWSeif6axrYpVCyERIDEKrX5AV rOmGEaUGsCd16FueoaM2Hf96BH3SI3/q2w+g058RedLOZVZtyQARAQABzSlBbnRvbmlvIFF1 YXJ0dWxsaSA8YW50b25pb0BtYW5kZWxiaXQuY29tPsLBrQQTAQgAVwIbAwULCQgHAwUVCgkI CwUWAgMBAAIeAQIXgAUJFZDZMhYhBMq9oSggF8JnIZiFx0jwzLaPWdFMBQJhFSq4GBhoa3Bz Oi8va2V5cy5vcGVucGdwLm9yZwAKCRBI8My2j1nRTC6+EACi9cdzbzfIaLxGfn/anoQyiK8r FMgjYmWMSMukJMe0OA+v2+/VTX1Zy8fRwhjniFfiypMjtm08spZpLGZpzTQJ2i07jsAZ+0Kv ybRYBVovJQJeUmlkusY3H4dgodrK8RJ5XK0ukabQlRCe2gbMja3ec/p1sk26z25O/UclB2ti YAKnd/KtD9hoJZsq+sZFvPAhPEeMAxLdhRZRNGib82lU0iiQO+Bbox2+Xnh1+zQypxF6/q7n y5KH/Oa3ruCxo57sc+NDkFC2Q+N4IuMbvtJSpL1j6jRc66K9nwZPO4coffgacjwaD4jX2kAp saRdxTTr8npc1MkZ4N1Z+vJu6SQWVqKqQ6as03pB/FwLZIiU5Mut5RlDAcqXxFHsium+PKl3 UDL1CowLL1/2Sl4NVDJAXSVv7BY51j5HiMuSLnI/+99OeLwoD5j4dnxyUXcTu0h3D8VRlYvz iqg+XY2sFugOouX5UaM00eR3Iw0xzi8SiWYXl2pfeNOwCsl4fy6RmZsoAc/SoU6/mvk82OgN ABHQRWuMOeJabpNyEzA6JISgeIrYWXnn1/KByd+QUIpLJOehSd0o2SSLTHyW4TOq0pJJrz03 oRIe7kuJi8K2igJrfgWxN45ctdxTaNW1S6X1P5AKTs9DlP81ZiUYV9QkZkSS7gxpwvP7CCKF n11s24uF1c44BGhGyuwSCisGAQQBl1UBBQEBB0DIPeCzGpzFfbnob2Usn40WGLsFClyFRq3q ZIA9v7XIJAMBCAfCwXwEGAEIACYWIQTKvaEoIBfCZyGYhcdI8My2j1nRTAUCaEbK7AIbDAUJ AeEzgAAKCRBI8My2j1nRTDKZD/9nW0hlpokzsIfyekOWdvOsj3fxwTRHLlpyvDYRZ3RoYZRp b4v6W7o3WRM5VmJTqueSOJv70VfBbUuEBSIthifY6VWlVPWQFKeJHTQvegTrZSkWBlsPeGvl L+Kjj5kHx998B8PqWUrFtFY0QP1St+JWHTYSBhhLYmbL5XgFPz4okbLE0W/QsVImPBvzNBnm 9VnkU9ixJDklB0DNg2YD31xsuU2nIdvNsevZtevi3xv+uLThLCf4rOmj7zXVb+uSr+YjW/7I z/qjv7TnzqXUxD2bQsyPq8tesEM3SKgZrX/3saE/wu0sTgeWH5LyM9IOf7wGRIHj7gimKNAq 2sCpVNqI/i/djp9qokCs9yHkUcqC76uftsyqiKkqNXMoZReugahQfCPN5o6eefBgy+QMjAeI BbpeDMTllESfZ98SxKdU/MDhCSM/5Bf/lFmgfX3zeBvt45ds/8pCGIfpI7VQECaA8pIpAZEB hi1wlfVsdZhAdO158EagqtuTOSwvlm9N01FwLjj9nm7jKE2YCyrgrrANC7QlsAO/r0nnqM9o Iz6CD01a5JHdc1U66L/QlFXHip3dKeyfCy4XnHL58PShxgEu6SxWYdrgWwmr3XXc6vZ8z7XS 3WbIEhnAgMQEu73PEZRgt6eVr+Ad175SdKz6bJw3SzJr1qE4FMb/nuTvD9pAtw== Organization: Mandelbit SRL In-Reply-To: <1f49b8f3-44c9-43f3-a3bf-b931fb0726f4@foss.st.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Hi Clement, On 30/06/2025 09:34, Clement LE GOFFIC wrote: > Hi Antonio, > > On 6/28/25 02:02, Antonio Quartulli wrote: >> In stm32_spi_prepare_rx_dma_mdma_chaining() both rx_dma_desc >> and rx_mdma_desc are passed as pointer-to-pointer arguments. >> >> The goal is to pass back to the caller the value returned >> by dmaengine_prep_slave_sg(), when it is not NULL. >> >> However, the NULL check on the result is erroneously >> performed without dereferencing the pointer. >> >> Add the proper dereference operator to both checks. >> >> Fixes: d17dd2f1d8a1 ("spi: stm32: use STM32 DMA with STM32 MDMA to >> enhance DDR use") >> Addresses-Coverity-ID: 1644715 ("Null pointer dereferences >> (REVERSE_INULL)") >> Signed-off-by: Antonio Quartulli >> --- >>   drivers/spi/spi-stm32.c | 6 +++--- >>   1 file changed, 3 insertions(+), 3 deletions(-) >> >> diff --git a/drivers/spi/spi-stm32.c b/drivers/spi/spi-stm32.c >> index 3d20f09f1ae7..e9fa17e52fb0 100644 >> --- a/drivers/spi/spi-stm32.c >> +++ b/drivers/spi/spi-stm32.c >> @@ -1529,7 +1529,7 @@ static int >> stm32_spi_prepare_rx_dma_mdma_chaining(struct stm32_spi *spi, >>                              DMA_PREP_INTERRUPT); >>       sg_free_table(&dma_sgt); >> -    if (!rx_dma_desc) >> +    if (!*rx_dma_desc) >>           return -EINVAL; >>       /* Prepare MDMA slave_sg transfer MEM_TO_MEM (SRAM>DDR) */ >> @@ -1563,8 +1563,8 @@ static int >> stm32_spi_prepare_rx_dma_mdma_chaining(struct stm32_spi *spi, >>                           DMA_PREP_INTERRUPT); >>       sg_free_table(&mdma_sgt); >> -    if (!rx_mdma_desc) { >> -        rx_dma_desc = NULL; >> +    if (!*rx_mdma_desc) { >> +        *rx_dma_desc = NULL; >>           return -EINVAL; >>       } > > Good catch for both pointers ! > > For readability, I would suggest to define two dma_async_tx_descriptor > ptr at the beginning of the function such as : >     struct dma_async_tx_descriptor *_mdma_desc = *rx_mdma_desc; >     struct dma_async_tx_descriptor *_dma_desc = *rx_dma_desc; > > And then use them all along the function even in the assignation. > Thanks for the comment. Will send v2! Regards, -- Antonio Quartulli CEO and Co-Founder Mandelbit Srl https://www.mandelbit.com