From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mout.web.de (mout.web.de [212.227.17.11]) (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 14F88176ABF for ; Wed, 26 Jun 2024 10:18:41 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=212.227.17.11 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1719397124; cv=none; b=EIJwnaZwYYWJxApqf/4B4JTpb6w+x5nxHRsT02KZ12/6ypJuKBoulKa1xS/j+nlXqvVJ9+MY0cID1+HAyiJhFqxy2/j224wNJl0PU1WKJ2l+z6KUqUI/zEigERAIHTWi8p+I8RSDQi2/HsFC4JkgM64dpMzNXZmhb2BxsZGjNLU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1719397124; c=relaxed/simple; bh=53Zj3oupdMLAkxnb/p1TFSSkwzxhFsLrokzhHfDoKFs=; h=Message-ID:Date:MIME-Version:To:Cc:References:Subject:From: In-Reply-To:Content-Type; b=LbBySlG4LfTswn9v91lBDFF+Gf2LzTMRinQ+Y6mE7fyT6YbZtIhOrRsBwzEfRaoQ4Qsc8QaWMV1JIRuE16nVbrGGI0UgzLOcszm53ujlPfpetflR26xHLF1FLpp33O0PkATvHvDXjI+koeYJ7K++vVlQVBchGfK9Ctk7NO3uWCE= 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=u8Mx57jx; arc=none smtp.client-ip=212.227.17.11 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="u8Mx57jx" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=web.de; s=s29768273; t=1719397090; x=1720001890; i=markus.elfring@web.de; bh=GDfZxGNUScq9YaFwJpm3DeNY9vXyehcx9Z/G4rNFFu8=; 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=u8Mx57jxnQA2HGD/gqjBu6F8uG5HKfa2F+2OBaRwkr+20LWk4RYqw447eO6jBvn8 X7Mcesplc1Yl1OZoJp2nRkOfxRC+p4MyzDaU884Kc2nOs2bOZKMcshkWyzAQRJ6jK OHjgYBnCvFSgm451jc43H/jLjN+4IsmYw8fgSOR9hom1SB9yscjI5n2gng9BGKamS TWUBM3eKePNFEcPLox/5lyhan7VWMKgmwGWs4HcuVsQHIX+/n4QOIJiSOaUI1+Cfg C2VLkVnl6ZF/2niC0x77oaau7l3YPTS7lF8MDtEHv/Mph5e3uAjp2QS2q1H0CoFp6 ILRzqZ1A9A3unx0vuA== X-UI-Sender-Class: 814a7b36-bfc1-4dae-8640-3722d8ec6cd6 Received: from [192.168.178.21] ([94.31.91.95]) by smtp.web.de (mrweb106 [213.165.67.124]) with ESMTPSA (Nemesis) id 1M7elj-1sGeZb1TB7-00EUgG; Wed, 26 Jun 2024 12:18:10 +0200 Message-ID: <84c7c61a-9de2-47d7-8420-87a2b389e684@web.de> Date: Wed, 26 Jun 2024 12:18:08 +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 , dri-devel@lists.freedesktop.org, Daniel Vetter , David Airlie , Maarten Lankhorst , Maxime Ripard , Patrik Jakobsson , Thomas Zimmermann Cc: LKML References: <20240626011656.2763368-1-make24@iscas.ac.cn> Subject: Re: [PATCH] drm/gma500: fix null pointer dereference in psb_intel_lvds_get_modes Content-Language: en-GB From: Markus Elfring In-Reply-To: <20240626011656.2763368-1-make24@iscas.ac.cn> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable X-Provags-ID: V03:K1:01rFRwMVi3531kRlSNqKJqy4VVaSc7+o4NHk0MEHOFFnMzxhibA OivBn4+Jls90kxeCzxTEwynhxV0OwQNDGRzP4wVoPgwaVfgWvb/PoSayUoqslQu9/Z7Y9zQ 4d285myX/qYl+Aa+0vSnFYUU554DZdMMHnkwQpYDvrWQae1VihS6vbtWKxpYmS+nKkR2iV6 ldUqX3PD7wEBblXES11lw== X-Spam-Flag: NO UI-OutboundReport: notjunk:1;M01:P0:/inCr0aeIyA=;nhO+xV00Cmbe7kK9azANZthrrjl PBrZsmpM0GtlAby7gaDXVpqMPIXRglE3SBCutqGW5fJHCG7RqgbPfDxb4k7rbMBsUKOgNJJpx j7wS/agVibvRNb90iGvtO2xKjnYy5CHBg9JV0xtch4paWLQFy7pbFaNOsuO8Nr9RJW0G+4qHu mexbUT9rnWQAdTUz1rLOJbaU60QF/qlVITn4uPN5pbLNlSsYVKNFU+5Cvm7RNTrgpIaJu+EWv 8R3mqfpDsyTQm9pZa/OEVaI9lIkqN4MwaifT1aMTClWs1FzALN7L1qJg8dP0MoiXUk1WYeWYh 5z7dYWGwA0wEvaPlgNZhKCBryhrPHMrQuzHA8vZVSR8TclHpWlvuffqVipnuHHwrREJW/3nx3 ojhdX5N3Fo48hMJkF6Vvb+UCrHQ/9biZ171+bXiqEtn+l0+XlpFdwb1vwrLOdMHcm+8lViNTr Wan7w8dZUkkvJeWZ7cDOc+dDDrdryk2SaDyIWvpG2mv9J6U/WL2AaKh3g3tLVnKeij4S8R5zo 50wag07jxlQv7FHdFSKKWrhgtvcfXZRW9kfhGA/IWDSeZOLCejZupPSWPLF+/tZEBb9rlDPfl dvoaCV+sBtBeU0tcE72DohGfKkpPfVxj1UMkoWc6Lk0G852MAUaT8lht2lNIiGuz/I1+i3i02 N/px5BICmuIdqET1HOAkIdEK8QcIzoZJDu6jgi0zozqBr1tNyxh8MSKr0T3PnqWoFOuZNtGBY wcyoryzCv6M0u3VGX3oiu39xRcQEmYuEHfZ8C1spLSOQikSAl5VKrFXTZZdXGoesdlPJhsYnI 5gg0I/Z2+rnCr24QYTFiBy/HQWRYOlioF0xWWMdzJsK7o= > In psb_intel_lvds_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