From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from 003.mia.mailroute.net (003.mia.mailroute.net [199.89.3.6]) (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 53F9A1C3308; Thu, 10 Apr 2025 20:46:43 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=199.89.3.6 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1744318006; cv=none; b=TT0Rqi5m3bdMFdmHKRGS6BgOLH604t+O2KjyKlraleGQPO6ntVxyDk3safrwZaiooPbjEhsWZBLs/ne7YwEI4OJH3GCiUpiYrCMJdL3vCGUtokIfnck6PXgKNZfaYeM+mK7KWLT7+jiOYM6PWV0GErhAB0vufwFPoMNl5GluNAE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1744318006; c=relaxed/simple; bh=jjfz2sEMmj3peUrbRTcapLbGRPdp9xvU05ee8BNL0aE=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=r3tfyEbqIOimLEFYOc6Na7Fab8fqcp84FpH7sCKsbDSJzy/UPJdA8aVHIjPhXAcU1Fe6HLB+YjgPJ65J6He2I0G1C6GPO4/yXV1DFYgIW5DBfcviSeIyn5cgnkk8JoFHJC9dq0yBVoXA1uYAZsan9XxTn3pr/UbK1lDcp7MRzUc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=acm.org; spf=pass smtp.mailfrom=acm.org; dkim=pass (2048-bit key) header.d=acm.org header.i=@acm.org header.b=XIpmAoOK; arc=none smtp.client-ip=199.89.3.6 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=acm.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=acm.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=acm.org header.i=@acm.org header.b="XIpmAoOK" Received: from localhost (localhost [127.0.0.1]) by 003.mia.mailroute.net (Postfix) with ESMTP id 4ZYX0q5RdTzlvyCJ; Thu, 10 Apr 2025 20:46:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=acm.org; h= content-transfer-encoding:content-type:content-type:in-reply-to :from:from:content-language:references:subject:subject :user-agent:mime-version:date:date:message-id:received:received; s=mr01; t=1744317993; x=1746909994; bh=zJFyeR0ZWJOawptBl+t2NsUC 50GEMlG6RIBSklFrDh0=; b=XIpmAoOKHsNBm4m052pDE3oYjDOgZPFWakcJWrfh 8Gn/UdEOc0jG8GcOK6cECTcpgCxIkDgrbGF/W0zHpVRlSViHKQjhAJ1ECIHOXmTx G9lSyFaB9mNQgfvz3kcyHhVHc9LwsFdXHJr1sZVQtYV4f4Ti3jC77fsRgpw7G3O7 Zm/d/6AjiBxODMa8P82WrWk4vrBkQxCcGuMQwuXdpp6dXL4JAxDNFMG+uRrN8aQx EgwaBL9dbXmvXeiwQj/AnMM6ItoRjhqpwfHtcJz8jrnuvzsvPu5WIf5OHJx4S2v8 42gA9a8zTuy5vnJ0mQvvGMAGrrY3KKekHzxuyW2lyHKekA== X-Virus-Scanned: by MailRoute Received: from 003.mia.mailroute.net ([127.0.0.1]) by localhost (003.mia [127.0.0.1]) (mroute_mailscanner, port 10029) with LMTP id hW6_3JHwXHxY; Thu, 10 Apr 2025 20:46:33 +0000 (UTC) Received: from [100.66.154.22] (unknown [104.135.204.82]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) (Authenticated sender: bvanassche@acm.org) by 003.mia.mailroute.net (Postfix) with ESMTPSA id 4ZYX0b5XN4zlvyCC; Thu, 10 Apr 2025 20:46:22 +0000 (UTC) Message-ID: <5c4b5e2e-eac1-4be5-bf72-2c151979a5cf@acm.org> Date: Thu, 10 Apr 2025 13:46:21 -0700 Precedence: bulk X-Mailing-List: linux-scsi@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v2] scsi: ufs: mcq: Add NULL check in ufshcd_mcq_abort() To: Chenyuan Yang , alim.akhtar@samsung.com, avri.altman@wdc.com, James.Bottomley@HansenPartnership.com, martin.petersen@oracle.com, peter.wang@mediatek.com, minwoo.im@samsung.com, manivannan.sadhasivam@linaro.org, viro@zeniv.linux.org.uk, cw9316.lee@samsung.com, quic_nguyenb@quicinc.com, quic_cang@quicinc.com, stanley.chu@mediatek.com Cc: linux-scsi@vger.kernel.org, linux-kernel@vger.kernel.org References: <20250410001320.2219341-1-chenyuan0y@gmail.com> Content-Language: en-US From: Bart Van Assche In-Reply-To: <20250410001320.2219341-1-chenyuan0y@gmail.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 4/9/25 5:13 PM, Chenyuan Yang wrote: > A race can occur between the MCQ completion path and the abort handler: > once a request completes, __blk_mq_free_request() sets rq->mq_hctx to > NULL, meaning the subsequent ufshcd_mcq_req_to_hwq() call in > ufshcd_mcq_abort() can return a NULL pointer. If this NULL pointer is > dereferenced, the kernel will crash. > > Add a NULL check for the returned hwq pointer. If hwq is NULL, log an > error and return FAILED, preventing a potential NULL-pointer dereference. > As suggested by Bart, the ufshcd_cmd_inflight() check is removed. > > This is similar to the fix in commit 74736103fb41 > ("scsi: ufs: core: Fix ufshcd_abort_one racing issue"). > > This is found by our static analysis tool KNighter. Reviewed-by: Bart Van Assche