From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mx0a-001b2d01.pphosted.com (mx0a-001b2d01.pphosted.com [148.163.156.1]) (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 125EF38A700; Mon, 10 Aug 2026 19:23:17 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=148.163.156.1 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786389801; cv=none; b=ZmcqbN/PZ2wDXRZ5h2k+oDHq1ri2inoJ9bkn3Fr+5Q9zpULMvHViMr3kX8piYZ7er+uXbkaZl7ey4PDeFtnBPLhz1gJXS7t8akpqUmvrfDm3Sk3ADgfGTEkQj4kOqJP3rxCgEOxbiWDhGh3tRi9f+6DVtyospV4uVxXzlxP0pU4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786389801; c=relaxed/simple; bh=A91BXmgS4+Y6X+9eJyK4oy0VXJCaYGlUROXv1Ek/8RQ=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=Kkh5+HjVxBmz+EGBG72yQWQRVY8MFxr8YvKkLMEQnZO1ufUaqCgjG8k+COxjXytW+BBNoNdYn8G/POjcMx2fIv10Fi2QnUexrmRCesH3eQoyW2oPIxeAvPzIkUyHh2O9+2IubFod1tI6PiCNK1jei73QDV9UauYH6/tG+H7lRd4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.ibm.com; spf=pass smtp.mailfrom=linux.ibm.com; dkim=pass (2048-bit key) header.d=ibm.com header.i=@ibm.com header.b=o6YdRx6z; arc=none smtp.client-ip=148.163.156.1 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.ibm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.ibm.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=ibm.com header.i=@ibm.com header.b="o6YdRx6z" Received: from pps.filterd (m0353729.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.18.1.11/8.18.1.11) with ESMTP id 67AJ29hj613725; Mon, 10 Aug 2026 19:23:09 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ibm.com; h=cc :content-transfer-encoding:date:from:in-reply-to:message-id :mime-version:references:subject:to; s=pp1; bh=MNuGs9mO+dy7lv21b Tkp4UsvfApLsygFm356gsfXoY8=; b=o6YdRx6zDPKesvLPK79v7gEwIVU5Yluk4 NOiy1feoExRHar350mbVrUoHAiE8uGVXeanI/hSWYji8E76OSOAitYSpFQNShhof +Pqti+goqJUD0RMHo3GMhob9ts+rDcnTeniJLbwnUQefCwQxrre5O8bTzTsYQTmC fmV/eLaJbhPwzeRfnMo1AqC/daxX+VAnsihFG6WaiW4prV5PyDXI4A7D/5PnpY3I RAx2YND5Ams8dLY1lF4szSYdXz6I354hhxgaF+FrUJDlykxeXx+FIK4iJ8665jaX ePnUuXuX4imxNrhAS20Xz02ToxWCCafqUowwwcH4krVpgjsUKtsJA== Received: from ppma12.dal12v.mail.ibm.com (dc.9e.1632.ip4.static.sl-reverse.com [50.22.158.220]) by mx0a-001b2d01.pphosted.com (PPS) with ESMTPS id 4fwvjysqu3-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Mon, 10 Aug 2026 19:23:08 +0000 (GMT) Received: from pps.filterd (ppma12.dal12v.mail.ibm.com [127.0.0.1]) by ppma12.dal12v.mail.ibm.com (8.18.1.7/8.18.1.7) with ESMTP id 67AJBd8v014697; Mon, 10 Aug 2026 19:23:07 GMT Received: from smtprelay07.wdc07v.mail.ibm.com ([172.16.1.74]) by ppma12.dal12v.mail.ibm.com (PPS) with ESMTPS id 4fxespx9sc-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Mon, 10 Aug 2026 19:23:07 +0000 (GMT) Received: from smtpav01.dal12v.mail.ibm.com (smtpav01.dal12v.mail.ibm.com [10.241.53.100]) by smtprelay07.wdc07v.mail.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 67AJN6Wd31392286 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Mon, 10 Aug 2026 19:23:06 GMT Received: from smtpav01.dal12v.mail.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 1357F58061; Mon, 10 Aug 2026 19:23:06 +0000 (GMT) Received: from smtpav01.dal12v.mail.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 0656B58059; Mon, 10 Aug 2026 19:23:05 +0000 (GMT) Received: from li-4c4c4544-004d-4810-8043-b7c04f423534.ibm.com.com (unknown [9.61.71.153]) by smtpav01.dal12v.mail.ibm.com (Postfix) with ESMTP; Mon, 10 Aug 2026 19:23:04 +0000 (GMT) From: Anthony Krowiak To: linux-s390@vger.kernel.org, linux-kernel@vger.kernel.org, kvm@vger.kernel.org Cc: jjherne@linux.ibm.com, borntraeger@de.ibm.com, mjrosato@linux.ibm.com, pasic@linux.ibm.com, alex@shazbot.org, kwankhede@nvidia.com, fiuczy@linux.ibm.com, pbonzini@redhat.com, frankja@linux.ibm.com, imbrenda@linux.ibm.com, agordeev@linux.ibm.com, hca@linux.ibm.com, gor@linux.ibm.com, stable@vger.kernel.org Subject: [PATCH v2 6/8] s390/vfio-ap: fix potential use of uninitialized apm_filtered bitmap Date: Mon, 10 Aug 2026 15:22:55 -0400 Message-ID: <20260810192257.1208410-7-akrowiak@linux.ibm.com> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20260810192257.1208410-1-akrowiak@linux.ibm.com> References: <20260810192257.1208410-1-akrowiak@linux.ibm.com> Precedence: bulk X-Mailing-List: kvm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-TM-AS-GCONF: 00 X-Proofpoint-Spam-Details-Enc: AW1haW4tMjYwODEwMDE2MiBTYWx0ZWRfXyPVYjSLEikmp 4WTCUHqcF1ABO/gcYSwETOFz6kDzOVXjo1GkHAZ+nh7+N4+/YNpuftb3cR+AqdYS1X0XnU2CkHe PoSWX9+NK3Ks7exfFNtN7tzt4q6H91r2FJ4ner1CVIoBKfIiBQ212LR2JmiJJ5fTyjMYbJosT/4 bCXeL40deuW9BUhDT0O5TFSBSZ2VEXHhqSFIEm/VdQz+Dgb3u7W9CYD0XZ/i5s5IFb2YUe1E+LL NcWBAjWWuUx7Uf2qyqFExQXxn3UVtohlEqQRaNLcX9q1YjN6QyFXcLzMLbmE26q60tQCmtz0Tjn ubRRPm+jnR4Uh9AU1LNMaqnAQPhJMEsliQ0Yf98nlgE/nwNvMo0/LCowz6G8Dci91HTtji2tpD8 Ne0FXJWnzUpeJBOyU1j6FSsYVT9NKTn7xwsd4i1Qq/pVyADqp0kHqW8pGBTsE2mcOAwHePy+kdq GMYZvmYblCBf4iW/++g== X-Proofpoint-Spam-Info: AW1haW4tMjYwODEwMDE2MiBTYWx0ZWRfX22fwf6O6bVZ7 EFVYbZRqK1Dj7X0G7csaa8L6gK1xgjV6ilay5NU5xmMGOfofNf5OpZol+26NQYlacrUTZaCMSv0 9ehlY2dYd1hU9PwWc6H/gt9iGoVt9ME= X-Authority-Analysis: v=2.4 cv=RqD16imK c=1 sm=1 tr=0 ts=6a7a251c cx=c_pps a=bLidbwmWQ0KltjZqbj+ezA==:117 a=bLidbwmWQ0KltjZqbj+ezA==:17 a=Sv0fKeRqtYgA:10 a=VkNPw1HP01LnGYTKEx00:22 a=RnoormkPH1_aCDwRdu11:22 a=uAbxVGIbfxUO_5tXvNgY:22 a=VwQbUJbxAAAA:8 a=VnNF1IyMAAAA:8 a=_H5xUuJxPEx76qSOziYA:9 X-Proofpoint-GUID: UYKu45aP7t89TYs43j3zO8PwaSMVS2H1 X-Proofpoint-ORIG-GUID: UYKu45aP7t89TYs43j3zO8PwaSMVS2H1 X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1176,Hydra:6.1.134,FMLib:17.12.100.49 definitions=2026-08-10_05,2026-08-10_02,2025-10-01_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 phishscore=0 priorityscore=1501 suspectscore=0 lowpriorityscore=0 clxscore=1015 adultscore=0 bulkscore=0 malwarescore=0 impostorscore=0 spamscore=0 classifier=typeunknown authscore=0 authtc= authcc= route=outbound adjust=0 reason=mlx scancount=1 engine=8.22.0-2606150000 definitions=main-2608100162 The DECLARE_BITMAP(apm_filtered, AP_DEVICES) macro allocates the bitmap on the stack without zero-initializing it. In vfio_ap_mdev_hot_plug_cfg(), the vfio_ap_mdev_filter_matrix() function is only called to initialize and populate apm_filtered if either filter_adapters or filter_domains is true. If the hot plug configuration change only adds control domains (meaning filter_cdoms is true, but filter_adapters and filter_domains are both false), vfio_ap_mdev_filter_matrix() is bypassed. Consequently, apm_filtered is passed to reset_queues_for_apids() with uninitialized stack garbage. This can cause reset_queues_for_apids() to interpret arbitrary stack garbage bits as valid APIDs to reset, potentially performing unintended guest hardware queue resets. Fix this by zero-initializing the apm_filtered bitmap at the beginning of vfio_ap_mdev_hot_plug_cfg() using bitmap_zero(). Fixes: eeb386aeb5b7c ("s390/vfio-ap: handle config changed and scan complete notification") Cc: stable@vger.kernel.org Signed-off-by: Anthony Krowiak --- drivers/s390/crypto/vfio_ap_ops.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/s390/crypto/vfio_ap_ops.c b/drivers/s390/crypto/vfio_ap_ops.c index 9c7257c179a7..061bbad20291 100644 --- a/drivers/s390/crypto/vfio_ap_ops.c +++ b/drivers/s390/crypto/vfio_ap_ops.c @@ -2836,6 +2836,8 @@ static void vfio_ap_mdev_hot_plug_cfg(struct ap_matrix_mdev *matrix_mdev) DECLARE_BITMAP(apm_filtered, AP_DEVICES); bool filter_domains, filter_adapters, filter_cdoms, do_hotplug = false; + bitmap_zero(apm_filtered, AP_DEVICES); + filter_adapters = bitmap_intersects(matrix_mdev->matrix.apm, matrix_mdev->apm_add, AP_DEVICES); filter_domains = bitmap_intersects(matrix_mdev->matrix.aqm, -- 2.53.0