From patchwork Fri Apr 26 12:25:11 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Rajashekar Kuruva (Temp)" X-Patchwork-Id: 13644720 Received: from mx0b-0031df01.pphosted.com (mx0b-0031df01.pphosted.com [205.220.180.131]) (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 A5E9114535C; Fri, 26 Apr 2024 12:26:05 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=205.220.180.131 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1714134367; cv=none; b=EISiH7ahcGl5V2lOvHHOfez7SlP1Zh1wP9hibuStpANSkkXfi9dpUF4Vqi4HgtTc6HlQGO7FEEotPIXHi+TeKTBXSEH7lm3NwkgDTHMTkT27qWcqb8+ZggVUB8BJtcQGC3w8mxtuZsaSoguXDsrbCoTrD5DWCTwWD03/MyaBb2I= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1714134367; c=relaxed/simple; bh=dYh57E6ZQFNHZXIEQC6AnVwy5RS0Foaz8BUdG7uKogU=; h=From:To:CC:Subject:Date:Message-ID:MIME-Version:Content-Type; b=j02TNXSiUSWtH8fwTLATSsaHHuHWJt617A0tQdqjDykN4ygVI5tkROko3bqdmo2BxD2ynhKg3IfcsgJVXc2/oQR4/sU4ls/6yNnQKeANQovdz9yRRQ175kqaSf1SYcJ4fvCvpLoO36YvVs1OEqLSGFD+hWjhF1PsPE4BydseyvI= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=quicinc.com; spf=pass smtp.mailfrom=quicinc.com; dkim=pass (2048-bit key) header.d=quicinc.com header.i=@quicinc.com header.b=Q/okE3gT; arc=none smtp.client-ip=205.220.180.131 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=quicinc.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=quicinc.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=quicinc.com header.i=@quicinc.com header.b="Q/okE3gT" Received: from pps.filterd (m0279871.ppops.net [127.0.0.1]) by mx0a-0031df01.pphosted.com (8.18.1.2/8.18.1.2) with ESMTP id 43QBdJgL011896; Fri, 26 Apr 2024 12:25:43 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=quicinc.com; h= from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding:content-type; s=qcppdkim1; bh=fHEAhtk w2wOoewJBYMs/2MEtu56/1mA6pRiADYx7uCk=; b=Q/okE3gTGMdnRj5Q6etX5yv OWmDLBFHKWmhfBMmRImGE0JvHEPulvsghahGPWjUWsA+D/2OVkjimZk8nQimLnIj r5gCIxXMlYlOWVzZZzPFJxs2a5qkE2DcKPfOAaK/1rvPmfR5SUwg1s4YPbyjpyIF oQGXbtucyrk5EFeCSkvjKD8lBEWoMOVFW4BdQIdM+ErOB8v7M6SH6W79cBZ/2Ybq L5Ot9ZqTtmdm5iFJOuafZNIlznc9IxKE+xkO+akwHdgMtQ8AkQA0UDh8WG420dpL GdtSn/03nM1cSMxqAgSF55Ko92TZR5BjMYhF7TJXnyzRDWC0ckG2b3GYNzHk8yg= = Received: from nasanppmta03.qualcomm.com (i-global254.qualcomm.com [199.106.103.254]) by mx0a-0031df01.pphosted.com (PPS) with ESMTPS id 3xr3591t0v-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Fri, 26 Apr 2024 12:25:43 +0000 (GMT) Received: from nasanex01c.na.qualcomm.com (nasanex01c.na.qualcomm.com [10.45.79.139]) by NASANPPMTA03.qualcomm.com (8.17.1.5/8.17.1.5) with ESMTPS id 43QCPf37005147 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Fri, 26 Apr 2024 12:25:41 GMT Received: from hu-kuruva-hyd.qualcomm.com (10.80.80.8) by nasanex01c.na.qualcomm.com (10.45.79.139) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.1544.9; Fri, 26 Apr 2024 05:25:35 -0700 From: Rajashekar kuruva To: , , , , , , , , , , , , , , CC: , , , , , , , Rajashekar kuruva Subject: [PATCH] [RFC PATCH] ALSA: usb-audio: endpoint: Prevent NULL pointer deference in snd_usb_endpoint_close Date: Fri, 26 Apr 2024 17:55:11 +0530 Message-ID: <20240426122511.547755-1-quic_kuruva@quicinc.com> X-Mailer: git-send-email 2.25.1 Precedence: bulk X-Mailing-List: linux-sound@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-ClientProxiedBy: nasanex01a.na.qualcomm.com (10.52.223.231) To nasanex01c.na.qualcomm.com (10.45.79.139) X-QCInternal: smtphost X-Proofpoint-Virus-Version: vendor=nai engine=6200 definitions=5800 signatures=585085 X-Proofpoint-GUID: 3qfEpPMRQq5Ur703ay_jX8btNchQt73f X-Proofpoint-ORIG-GUID: 3qfEpPMRQq5Ur703ay_jX8btNchQt73f X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1011,Hydra:6.0.650,FMLib:17.11.176.26 definitions=2024-04-26_12,2024-04-26_02,2023-05-22_02 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 malwarescore=0 spamscore=0 impostorscore=0 lowpriorityscore=0 priorityscore=1501 adultscore=0 clxscore=1011 mlxscore=0 suspectscore=0 phishscore=0 mlxlogscore=968 bulkscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.19.0-2404010003 definitions=main-2404260082 When multiple plug-in and plug-out events occur, there is a risk of encountering a NULL pointer dereference leading to a kernel panic during a headset use-case. this issue arises in the snd_usb_endpoint_close function To avoid check if ep->iface_ref is not null before decrementing its opened count. If ep->iface_ref is null, we skip the decrement and the subsequent logic. Signed-off-by: Rajashekar kuruva --- sound/usb/endpoint.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/sound/usb/endpoint.c b/sound/usb/endpoint.c index 8f65349a06d3..0e3101b7e392 100644 --- a/sound/usb/endpoint.c +++ b/sound/usb/endpoint.c @@ -950,7 +950,7 @@ void snd_usb_endpoint_close(struct snd_usb_audio *chip, usb_audio_dbg(chip, "Closing EP 0x%x (count %d)\n", ep->ep_num, ep->opened); - if (!--ep->iface_ref->opened && + if (ep->iface_ref && !--ep->iface_ref->opened && !(chip->quirk_flags & QUIRK_FLAG_IFACE_SKIP_CLOSE)) endpoint_set_interface(chip, ep, false);