From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mout.web.de (mout.web.de [212.227.17.12]) (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 9989C17D88D for ; Wed, 26 Jun 2024 11:35:44 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=212.227.17.12 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1719401747; cv=none; b=l1eYGmDubR7pfp4W7vMD36zQWgBg3HCi8TE7iubMqzXIaE42HDKH1qXMBTeUEWz5Jp+rN5DvOwWSKfq0uvA4oV2lyrgQxJ7pTwgU30KFKVOQfce5+hh8VFIE6wg/DVwXjTThrsgjRkw8cdMhjiJj1qn2SR3USISpZITyfbew8ew= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1719401747; c=relaxed/simple; bh=AaEMS6qR5hEt+fGbmtkaq98HXCiBPbuz/W1mjVP+QyQ=; h=Message-ID:Date:MIME-Version:To:Cc:References:Subject:From: In-Reply-To:Content-Type; b=LLOJw6Vv1ew7wfG5xLBAIsMuShsyHMe+MSR83XLrTDnoSUL8G0D9H5hO1e9Xu3m4MGvzqoYzuAt3wcNkjVx2IDJ/ixrZcVBQ3aeKGqaXZ34ZtCG7mCFXSNSdTCSTu3ENHx2jYQTzYlK0i30HVbalYNy+QdMVM5T+7gqLIc0B3Oo= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=web.de; spf=pass smtp.mailfrom=web.de; dkim=pass (2048-bit key) header.d=web.de header.i=markus.elfring@web.de header.b=lCJOiuLX; arc=none smtp.client-ip=212.227.17.12 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=web.de Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=web.de Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=web.de header.i=markus.elfring@web.de header.b="lCJOiuLX" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=web.de; s=s29768273; t=1719401727; x=1720006527; i=markus.elfring@web.de; bh=Dwr9KGkAvi7dk8APk978FQGIUeYfNk2QkN6QDYEkC/g=; h=X-UI-Sender-Class:Message-ID:Date:MIME-Version:To:Cc:References: Subject:From:In-Reply-To:Content-Type:Content-Transfer-Encoding: cc:content-transfer-encoding:content-type:date:from:message-id: mime-version:reply-to:subject:to; b=lCJOiuLXoeLABxcpKmSDv3kfLJVJrDSsgZ2E4m1jn8FkpyniN/jZ/5AW+MIwgF1+ LILPyrfexqdKtyTekSHIVuestAGKu2aMZaZXTbqUvWNWoQGPLsXx7Tpa7k8YqiCyS PaORiKyzMMtZwognSKmFFq+RDbNNUr1c9Jl2lvg7rTiul+RgeZqsAadsY/SxFT5LH zt6h9nYOoe9q3vmETv6YnhHbWqU8XcYa4Q49yZVTDLbGbSncaXQLmc2hR+QUM1gpA kHBWrN9g+nWiPj1LTECi1xb45h4U2jQjjKLqTkr3D6Z1Zawly9KiSyoc8fvLBsBVM 9YqzNhqdVAUcQWGDtA== X-UI-Sender-Class: 814a7b36-bfc1-4dae-8640-3722d8ec6cd6 Received: from [192.168.178.21] ([94.31.91.95]) by smtp.web.de (mrweb105 [213.165.67.124]) with ESMTPSA (Nemesis) id 1MTvrs-1rvNr32ceg-00P15i; Wed, 26 Jun 2024 13:35:27 +0200 Message-ID: <8b3ce177-96c1-4f6d-bf8b-dc466ab95162@web.de> Date: Wed, 26 Jun 2024 13:35:26 +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 To: Ma Ke , nouveau@lists.freedesktop.org, dri-devel@lists.freedesktop.org, Daniel Vetter , Danilo Krummrich , David Airlie , Karol Herbst , Lyude Paul Cc: LKML References: <20240626013013.2765395-1-make24@iscas.ac.cn> Subject: Re: [PATCH] drm/nouveau: fix null pointer dereference in nouveau_connector_get_modes Content-Language: en-GB From: Markus Elfring In-Reply-To: <20240626013013.2765395-1-make24@iscas.ac.cn> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable X-Provags-ID: V03:K1:vdUoZWbQeUPEE1CrCCpqXIhXfPjlHqMGoiMqlueLyAOOdfqi/Ix iAYZyBhapo6R10KYw5JshwGWYqrEIzqLP2todlpAoVGAk8/4O9lCokApTeDkMSsbfbyljlQ AfsuabdulpjcZakzrii2vczz9uHTq+NXQ0pH3X6w7DpBgaSFBl6HI84nP7By/JfBI61jp0n ZD8TD3ityNvJjY64kDQYA== X-Spam-Flag: NO UI-OutboundReport: notjunk:1;M01:P0:F0+NrcTHtxs=;pyOXLYtsch5ZYLx8z7KNdJtGc7Z wATn6kwfBTuPeuotutgxncuInlajhMKG9as4SoYo28LLF6z3sdXCmhT+76Wkp4wC9ZhZcLXq1 W6iXMS3WEbhKIlBEEn0WTOfnl/REEjzJnzBoZP7YPghzkzpq+Bp43aiWLv+ph4bQd5TUh1S6X f039OtbVKQ/eZHaXjAJ4PH48cpjuXzjk1NLdvVSb/S/5wX505zR9fR1lS4b2zQ7/6oCMJcAqR z4nWbNgBIJUKYbs7/mq46lY4dkU6QsUlsrKQrIeQ/iKB81HIlIfbFPUn+xGwaaXFqaWmBcZTk K4Ffjc/nXy/K+oPlOXRj8vBntofWu3/z5s+GVBrXNratWBK4kBo9oGyq6LBQSLANZciIH5NDb 5c78886WO5k4oa3cL24AsWPPmT8hiHHZ7ZyS/7buWpmmI9XIpKO+UtHYUGDNGbmt1iOl4RuF/ ua++zxkuCLFx2AEU3t4X/vspmExHrkO0hWCDWji1uswUV993u6kTFy/wURCHgczcusHJ46aJW UBX10Co7IWqDbYbOkQMMhQq8VCNOUSL9vxhVKaRLGEkkvYjtcB6bhCYgQxmsjWJXU6AGDmpNz l6pNKQijrWxMgqWN0lfQSl5fK1wIPps+v4v/McmmUtH50CBES9INmDK2iqmbezC+NFFf8HxbU gtmksprIPkMy6dB62TQNp2hxrw/g0/QT6b3nYOj25oI3/9WTdSHJ0iwuGQ5+pv1GtquXU96rf 5PmRC56bEhKrbJzMyxAToLTYB2KE+1vBUKMhtkxmNiHqmDLO5VHLGb5XxSdE1aiKe5CMiaJ/2 vP6HOTeG+ZbxBA/t77z/8VvR+EkUDLcGYU3NHXX2G6PgU= > In nouveau_connector_get_modes(), the return value of drm_mode_duplicate= () > is assigned to mode, which will lead to a possible NULL pointer > dereference on failure of drm_mode_duplicate(). Add a check to avoid npd= . 1. Can a wording approach (like the following) be a better change descript= ion? A null pointer is stored in the local variable =E2=80=9Cmode=E2=80=9D a= fter a call of the function =E2=80=9Cdrm_mode_duplicate=E2=80=9D failed. This point= er was passed to a subsequent call of the function =E2=80=9Cdrm_mode_probed_add=E2=80=9D= where an undesirable dereference will be performed then. Thus add a corresponding return value check. 2. Would you like to add any tags (like =E2=80=9CFixes=E2=80=9D and =E2=80= =9CCc=E2=80=9D) accordingly? 3. How do you think about to append parentheses to the function name in the summary phrase? 4. How do you think about to put similar results from static source code analyses into corresponding patch series? Regards, Markus