From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from lists.ozlabs.org (lists.ozlabs.org [112.213.38.117]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 4FC56CD5BB1 for ; Mon, 25 May 2026 12:17:09 +0000 (UTC) Received: from boromir.ozlabs.org (localhost [127.0.0.1]) by lists.ozlabs.org (Postfix) with ESMTP id 4gPFHl5WKJz2xbN; Mon, 25 May 2026 22:17:07 +1000 (AEST) Authentication-Results: lists.ozlabs.org; arc=none smtp.remote-ip=148.163.158.5 ARC-Seal: i=1; a=rsa-sha256; d=lists.ozlabs.org; s=201707; t=1779711427; cv=none; b=h2ipPfztu7psJGZyd+KaoHDEPRgICoNNQuRouBkWv3xtnv3asRNoiJ2tnCoiApvEgbdm2LfNmreUNOxSX6xk8LOqHNcOtDPCvVHXIbbr2awnoVdvzqfoQFsUM+a91RYmOhNJ8nsjWwrSg20WRT0s3FBaoxnInsVVPqe2+o5HFxmfJdXGHsqahBGtu5SOLNFXVHdwtfwKRdfzlmGA5lzi3/hh11x0GN7mtvLRs1IPgh5hYSic8iAU8ff3kqjpzDSK1yFUAugNzk/w39B+XqWm/FKLiEe5vyrlNS/tpWALvfgkZMCp5/rkjrXiOvTBxBqO9+2qcgGd0NQ4NAB4xNO8Uw== ARC-Message-Signature: i=1; a=rsa-sha256; d=lists.ozlabs.org; s=201707; t=1779711427; c=relaxed/relaxed; bh=kcbhuYVnIyM0gO1Ey8OTwYSmRoXUoO+BdnB7Gvputxg=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=YC/WqOjlvcLaJjZJtQa9zvPy0ioKzF6v8kYXdG5KqHj5w0sLncUcW9HCCjZAQKTurpGWXtLbkSDOAAshQG6rApgp+elQ7b50fTmlvBEG/22RVfK4FPeiWadRcCK5mFBrbeCBUV2V5xMdZTszNS7scVSmQka/y7Ou1oqZdVvrjx3JZAz8SKGDrz6UCMb0BgbXpjYW2CTeHgrkEBJL2GCUtPTn/+DlUX3tPJsFJWcL0PaaU5bLXYMbOwIUtTpsm3j+DWY/gGw7S3DY0/Y+nCYgk6oGUNRqNDzgFnIVNlxk5Ol6h1IJB/OYEMfT8Qn6gzj6hXqSPWzwraLTxRUR08ARYg== ARC-Authentication-Results: i=1; lists.ozlabs.org; dmarc=pass (p=none dis=none) header.from=linux.ibm.com; dkim=pass (2048-bit key; unprotected) header.d=ibm.com header.i=@ibm.com header.a=rsa-sha256 header.s=pp1 header.b=Mp0HBVZj; dkim-atps=neutral; spf=pass (client-ip=148.163.158.5; helo=mx0b-001b2d01.pphosted.com; envelope-from=adityag@linux.ibm.com; receiver=lists.ozlabs.org) smtp.mailfrom=linux.ibm.com Authentication-Results: lists.ozlabs.org; dmarc=pass (p=none dis=none) header.from=linux.ibm.com Authentication-Results: lists.ozlabs.org; dkim=pass (2048-bit key; unprotected) header.d=ibm.com header.i=@ibm.com header.a=rsa-sha256 header.s=pp1 header.b=Mp0HBVZj; dkim-atps=neutral Authentication-Results: lists.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=linux.ibm.com (client-ip=148.163.158.5; helo=mx0b-001b2d01.pphosted.com; envelope-from=adityag@linux.ibm.com; receiver=lists.ozlabs.org) Received: from mx0b-001b2d01.pphosted.com (mx0b-001b2d01.pphosted.com [148.163.158.5]) (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) by lists.ozlabs.org (Postfix) with ESMTPS id 4gPFHk6JHNz2xSb for ; Mon, 25 May 2026 22:17:06 +1000 (AEST) Received: from pps.filterd (m0353725.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.18.1.11/8.18.1.11) with ESMTP id 64OJo5e13032008; Mon, 25 May 2026 12:16:49 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ibm.com; h=cc :content-transfer-encoding:date:from:message-id:mime-version :subject:to; s=pp1; bh=kcbhuYVnIyM0gO1Ey8OTwYSmRoXUoO+BdnB7Gvput xg=; b=Mp0HBVZj1/HtF9sBIL6MPfsxSIyjH4SRA7eXNKIJlsdiaBrkwuREZxFFU OqZ5OSZryje6H9/mOd2KZKYdrvrOei9rPLxoBgqgKERTdQHbeFXBo33xjDtZgk0l cctvz1m0diw1QcK+F9+i75+VjVQZVJ2JNi6GfynoMuedFuIuI6FBjrZv5bEK+wr3 LVsxRIgyBn46p/X3eIo0+w2Cjt7YgpVzmAt+4PbkSbY0oiW9leDqFWKXpl8lDREr mL7uyR3P9PG+BwyD4owiZU4LrMghOPpU/TROP8urvBVJWtwvwLbKH6vQA4bsS29H bfLaCiOx2uV5oq4BuMNPgpV8+JH4w== Received: from ppma21.wdc07v.mail.ibm.com (5b.69.3da9.ip4.static.sl-reverse.com [169.61.105.91]) by mx0a-001b2d01.pphosted.com (PPS) with ESMTPS id 4eb4nbxwre-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Mon, 25 May 2026 12:16:48 +0000 (GMT) Received: from pps.filterd (ppma21.wdc07v.mail.ibm.com [127.0.0.1]) by ppma21.wdc07v.mail.ibm.com (8.18.1.7/8.18.1.7) with ESMTP id 64PC9AIC011263; Mon, 25 May 2026 12:16:48 GMT Received: from smtprelay05.fra02v.mail.ibm.com ([9.218.2.225]) by ppma21.wdc07v.mail.ibm.com (PPS) with ESMTPS id 4ebqjjn2x6-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Mon, 25 May 2026 12:16:47 +0000 (GMT) Received: from smtpav06.fra02v.mail.ibm.com (smtpav06.fra02v.mail.ibm.com [10.20.54.105]) by smtprelay05.fra02v.mail.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 64PCGikO42860928 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Mon, 25 May 2026 12:16:44 GMT Received: from smtpav06.fra02v.mail.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id F151C2004B; Mon, 25 May 2026 12:16:43 +0000 (GMT) Received: from smtpav06.fra02v.mail.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 2275D20040; Mon, 25 May 2026 12:16:40 +0000 (GMT) Received: from li-3c92a0cc-27cf-11b2-a85c-b804d9ca68fa.ibm.com (unknown [9.124.218.95]) by smtpav06.fra02v.mail.ibm.com (Postfix) with ESMTP; Mon, 25 May 2026 12:16:39 +0000 (GMT) From: Aditya Gupta To: linux-kernel@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, Madhavan Srinivasan , Timothy Pearson , Bjorn Helgaas , Shawn Anastasio Cc: linux-pci@vger.kernel.org, Michael Ellerman , Nicholas Piggin , "Christophe Leroy (CS GROUP)" , stable@vger.kernel.org Subject: [PATCH] ppc/pnv: Fix null pointer deref in pci hotplug Date: Mon, 25 May 2026 17:46:28 +0530 Message-ID: <20260525121628.3906457-1-adityag@linux.ibm.com> X-Mailer: git-send-email 2.54.0 X-Mailing-List: linuxppc-dev@lists.ozlabs.org List-Id: List-Help: List-Owner: List-Post: List-Archive: , List-Subscribe: , , List-Unsubscribe: Precedence: list MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-TM-AS-GCONF: 00 X-Proofpoint-Reinject: loops=2 maxloops=12 X-Authority-Analysis: v=2.4 cv=VvYTxe2n c=1 sm=1 tr=0 ts=6a143db1 cx=c_pps a=GFwsV6G8L6GxiO2Y/PsHdQ==:117 a=GFwsV6G8L6GxiO2Y/PsHdQ==:17 a=NGcC8JguVDcA:10 a=VkNPw1HP01LnGYTKEx00:22 a=RnoormkPH1_aCDwRdu11:22 a=V8glGbnc2Ofi9Qvn3v5h:22 a=VwQbUJbxAAAA:8 a=VnNF1IyMAAAA:8 a=lml1KbhEJxe8kdhi6MYA:9 X-Proofpoint-ORIG-GUID: B4AjfRteot1akFQ4FhifVoHIFDoqMvAJ X-Proofpoint-GUID: j1ytpDlrHCLjuc5MFTTqjFIu-2Pq4kAT X-Proofpoint-Spam-Details-Enc: AW1haW4tMjYwNTI1MDEyNSBTYWx0ZWRfX8DynBRZ5R9JV A47tk1xLWQfh15pvCoJ/kWw821rXRAVTVUQkZEHsAYrz2muZdyg2ZKeoYU+AST9sWjxzJTFmb0R SXVl67H3QIR9WRRfGZUu6Gts/PdQtzg2qZQx7rIY5UqMr7b2iAd4lv5B29z2d0vPL7rpuWoHYgp bwgF7qB9EZMK2xmkCoUnc1pIssEW5G4/Bxs91WvvyyJOkhIgBzrb9B3FtAmpHFoQcsVFq99ITsb SlTyohakBR1o63i4e6O0yxfNJ/BtQUbkrzj9c9NN8R8iymLm/kprGIjTQ4nNL3ROHFQj8redOMY LLJGn/ElQIHT6xtTgXQv2wtdGakUXmokgvRtLNKLUvi1puWlJB6SfwVQjGRCQ4zEt9tmsYuE8Ys kapZad0DEMwU+218zFxJoFTUSlTfIeFgoBSXI4d9vwEggGnhaUGUqoKOGFzuxgehvWVGCG2MlQp p98HsvNkCnk55IHZ7vg== X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1143,Hydra:6.1.51,FMLib:17.12.100.49 definitions=2026-05-25_03,2026-05-18_01,2025-10-01_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 suspectscore=0 phishscore=0 priorityscore=1501 spamscore=0 adultscore=0 lowpriorityscore=0 malwarescore=0 impostorscore=0 clxscore=1011 bulkscore=0 classifier=typeunknown authscore=0 authtc= authcc= route=outbound adjust=0 reason=mlx scancount=1 engine=8.22.0-2605130000 definitions=main-2605250125 With upstream kernel booted on a PowerNV system with OpenCAPI device, below crash is observed: [ 1.568588] PowerPC PowerNV PCI Hotplug Driver version: 0.1 [ 1.569722] BUG: Kernel NULL pointer dereference at 0x00000074 [ 1.569811] Faulting instruction address: 0xc000000000b75fd0 [ 1.569890] Oops: Kernel access of bad area, sig: 11 [#1] [ 1.569963] LE PAGE_SIZE=64K MMU=Hash SMP NR_CPUS=2048 NUMA PowerNV [ 1.570037] Modules linked in: [ 1.570099] CPU: 250 UID: 0 PID: 1 Comm: swapper/248 Not tainted 7.1.0-rc4+ #1 PREEMPTLAZY [ 1.570207] Hardware name: 9105-22A Power11 (raw) 0x820200 opal:v7.1-142-gbbc276524497 PowerNV [ 1.570325] NIP: c000000000b75fd0 LR: c000000000b75fbc CTR: 000000003008a65c [ 1.570411] REGS: c000c0000688f6f0 TRAP: 0380 Not tainted (7.1.0-rc4+) [ 1.570494] MSR: 9000000000009033 CR: 28000284 XER: 20040000 [ 1.570636] CFAR: c00000000019f9e8 IRQMASK: 0 ... [ 1.571492] NIP [c000000000b75fd0] pnv_php_get_adapter_state+0x60/0x154 [ 1.571604] LR [c000000000b75fbc] pnv_php_get_adapter_state+0x4c/0x154 [ 1.571690] Call Trace: [ 1.571725] [c000c0000688f990] [c000000000b75fbc] pnv_php_get_adapter_state+0x4c/0x154 (unreliable) [ 1.571783] [c000c0000688fa20] [c000000000b78bd0] pnv_php_enable+0x94/0x378 [ 1.571951] [c000c0000688fac0] [c000000000b7912c] pnv_php_register_one.isra.0+0x11c/0x1e0 [ 1.572077] [c000c0000688fb00] [c000000002091318] pnv_php_init+0x168/0x1b0 [ 1.572111] [c000c0000688fb80] [c00000000001103c] do_one_initcall+0x5c/0x450 [ 1.572162] [c000c0000688fc70] [c000000002006abc] do_initcalls+0x15c/0x29c [ 1.572283] [c000c0000688fd30] [c000000002006ec4] kernel_init_freeable+0x224/0x3e0 [ 1.572484] [c000c0000688fde0] [c000000000011578] kernel_init+0x30/0x268 [ 1.572562] [c000c0000688fe50] [c00000000000debc] ret_from_kernel_user_thread+0x14/0x1c [ 1.572667] ---- interrupt: 0 at 0x0 [ 1.572720] Code: 38810065 e90d0c78 f9010068 39000000 99210065 e8630020 4b6299c9 60000000 2c030000 418000ac e87f0058 89410065 55290636 2c090060 41820044 This NULL pointer dereference happens due to the call to 'pci_pcie_type(php_slot->pdev)' without checking if php_slot->pdev is NULL. This occurs for hotplug slots on root buses where bus->self == NULL, such as OpenCAPI PHB direct slots. An added debug print (not part of this patch) confirmed it was opencapi: [ 1.617227] pnv_php: slot 'OPENCAPI-0009' has NULL pdev (bus 0009:00, parent=NO (root bus)) [ 1.617308] pnv_php: slot 'OPENCAPI-0009' dn->full_name='pciex@603a000000000', compatible='ibm,power10-pau-opencapi-pciex' Add a NULL check for this. Cc: stable@vger.kernel.org Fixes: 80f9fc236279 ("PCI: pnv_php: Work around switches with broken presence detection") Signed-off-by: Aditya Gupta --- drivers/pci/hotplug/pnv_php.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/pci/hotplug/pnv_php.c b/drivers/pci/hotplug/pnv_php.c index ff92a5c301b8..21ce7ead9e19 100644 --- a/drivers/pci/hotplug/pnv_php.c +++ b/drivers/pci/hotplug/pnv_php.c @@ -414,7 +414,8 @@ static int pnv_php_get_adapter_state(struct hotplug_slot *slot, u8 *state) */ ret = pnv_pci_get_presence_state(php_slot->id, &presence); if (ret >= 0) { - if (pci_pcie_type(php_slot->pdev) == PCI_EXP_TYPE_DOWNSTREAM && + if (php_slot->pdev && + pci_pcie_type(php_slot->pdev) == PCI_EXP_TYPE_DOWNSTREAM && presence == OPAL_PCI_SLOT_EMPTY) { /* * Similar to pciehp_hpc, check whether the Link Active -- 2.54.0