From patchwork Thu May 5 13:27:30 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Miles Chen X-Patchwork-Id: 12839568 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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (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 DCC18C433F5 for ; Thu, 5 May 2022 13:28:47 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:Message-ID:Date:Subject:CC :To:From:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:In-Reply-To:References: List-Owner; bh=tEr5JICZi/hoEOXI0aohhZ7oJQcG6HgR6X9azcnycmQ=; b=GsrONQELRc9K96 ZSw+gkJOgvdIUZzsxssbzGZ0Ix0T0SZZeC4Uq42UkLmmtNr6zUt1znKuIyp2iNXDnhxs5tNor8o9m P6DiF3c1iYyaN8udOE44DUP7YYGm2p+wpTc9z4SSSpBpTPJ3bNZACoUjdevGTlRyBPe9S7bmJL9GG 8u7BCzi/dwmynqgGOxPxAtNYy3nBaoOpeWS7RmKk6GZHzYv1CLYa3EAzdDqUs8K/ymLwclGwjjh0h OYoDivyEzaUS3vHYvBSses8NObTaSPnyfUeCRtUacwybB0HPhXYOWB9tyAvQ6RSxewPyPwUqLX4bq WwrYgJ2kk5e0lp0Wj99w==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1nmbWG-00G1b7-TV; Thu, 05 May 2022 13:27:48 +0000 Received: from mailgw02.mediatek.com ([216.200.240.185]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1nmbWD-00G1XP-F0; Thu, 05 May 2022 13:27:47 +0000 X-UUID: 134f61bdd4ed493fb6fb046a71c3d419-20220505 X-CID-P-RULE: Release_Ham X-CID-O-INFO: VERSION:1.1.4, REQID:ccf6d6aa-02d6-4f89-8b76-0b768d3d3e27, OB:0, LO B:0,IP:0,URL:0,TC:0,Content:-20,EDM:0,RT:0,SF:0,FILE:0,RULE:Release_Ham,AC TION:release,TS:-20 X-CID-META: VersionHash:faefae9, CLOUDID:b93bb3b2-56b5-4c9e-8d83-0070b288eb6a, C OID:IGNORED,Recheck:0,SF:nil,TC:nil,Content:0,EDM:-3,File:nil,QS:0,BEC:nil X-UUID: 134f61bdd4ed493fb6fb046a71c3d419-20220505 Received: from mtkcas67.mediatek.inc [(172.29.193.45)] by mailgw02.mediatek.com (envelope-from ) (musrelay.mediatek.com ESMTP with TLSv1.2 ECDHE-RSA-AES256-SHA384 256/256) with ESMTP id 1318787774; Thu, 05 May 2022 06:27:35 -0700 Received: from mtkmbs07n1.mediatek.inc (172.21.101.16) by MTKMBS62DR.mediatek.inc (172.29.94.18) with Microsoft SMTP Server (TLS) id 15.0.1497.2; Thu, 5 May 2022 06:27:34 -0700 Received: from mtkmbs11n2.mediatek.inc (172.21.101.187) by mtkmbs07n1.mediatek.inc (172.21.101.16) with Microsoft SMTP Server (TLS) id 15.0.1497.2; Thu, 5 May 2022 21:27:32 +0800 Received: from mtksdccf07.mediatek.inc (172.21.84.99) by mtkmbs11n2.mediatek.inc (172.21.101.73) with Microsoft SMTP Server id 15.2.792.3 via Frontend Transport; Thu, 5 May 2022 21:27:32 +0800 From: Miles Chen To: Yong Wu , Joerg Roedel , "Will Deacon" , Matthias Brugger , AngeloGioacchino Del Regno , "Mauro Carvalho Chehab" , Hans Verkuil CC: Miles Chen , Robin Murphy , Joerg Roedel , , , , Subject: [PATCH v3] iommu/mediatek: Fix NULL pointer dereference when printing dev_name Date: Thu, 5 May 2022 21:27:30 +0800 Message-ID: <20220505132731.21628-1-miles.chen@mediatek.com> X-Mailer: git-send-email 2.18.0 MIME-Version: 1.0 X-MTK: N X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20220505_062745_546958_6BCDCE90 X-CRM114-Status: GOOD ( 16.70 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org When larbdev is NULL (in the case I hit, the node is incorrectly set iommus = <&iommu NUM>), it will cause device_link_add() fail and kernel crashes when we try to print dev_name(larbdev). Let's fail the probe if a larbdev is NULL to avoid invalid inputs from dts. It should work for normal correct setting and avoid the crash caused by my incorrect setting. Error log: [ 18.189042][ T301] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000050 ... [ 18.344519][ T301] pstate: a0400005 (NzCv daif +PAN -UAO) [ 18.345213][ T301] pc : mtk_iommu_probe_device+0xf8/0x118 [mtk_iommu] [ 18.346050][ T301] lr : mtk_iommu_probe_device+0xd0/0x118 [mtk_iommu] [ 18.346884][ T301] sp : ffffffc00a5635e0 [ 18.347392][ T301] x29: ffffffc00a5635e0 x28: ffffffd44a46c1d8 [ 18.348156][ T301] x27: ffffff80c39a8000 x26: ffffffd44a80cc38 [ 18.348917][ T301] x25: 0000000000000000 x24: ffffffd44a80cc38 [ 18.349677][ T301] x23: ffffffd44e4da4c6 x22: ffffffd44a80cc38 [ 18.350438][ T301] x21: ffffff80cecd1880 x20: 0000000000000000 [ 18.351198][ T301] x19: ffffff80c439f010 x18: ffffffc00a50d0c0 [ 18.351959][ T301] x17: ffffffffffffffff x16: 0000000000000004 [ 18.352719][ T301] x15: 0000000000000004 x14: ffffffd44eb5d420 [ 18.353480][ T301] x13: 0000000000000ad2 x12: 0000000000000003 [ 18.354241][ T301] x11: 00000000fffffad2 x10: c0000000fffffad2 [ 18.355003][ T301] x9 : a0d288d8d7142d00 x8 : a0d288d8d7142d00 [ 18.355763][ T301] x7 : ffffffd44c2bc640 x6 : 0000000000000000 [ 18.356524][ T301] x5 : 0000000000000080 x4 : 0000000000000001 [ 18.357284][ T301] x3 : 0000000000000000 x2 : 0000000000000005 [ 18.358045][ T301] x1 : 0000000000000000 x0 : 0000000000000000 [ 18.360208][ T301] Hardware name: MT6873 (DT) [ 18.360771][ T301] Call trace: [ 18.361168][ T301] dump_backtrace+0xf8/0x1f0 [ 18.361737][ T301] dump_stack_lvl+0xa8/0x11c [ 18.362305][ T301] dump_stack+0x1c/0x2c [ 18.362816][ T301] mrdump_common_die+0x184/0x40c [mrdump] [ 18.363575][ T301] ipanic_die+0x24/0x38 [mrdump] [ 18.364230][ T301] atomic_notifier_call_chain+0x128/0x2b8 [ 18.364937][ T301] die+0x16c/0x568 [ 18.365394][ T301] __do_kernel_fault+0x1e8/0x214 [ 18.365402][ T301] do_page_fault+0xb8/0x678 [ 18.366934][ T301] do_translation_fault+0x48/0x64 [ 18.368645][ T301] do_mem_abort+0x68/0x148 [ 18.368652][ T301] el1_abort+0x40/0x64 [ 18.368660][ T301] el1h_64_sync_handler+0x54/0x88 [ 18.368668][ T301] el1h_64_sync+0x68/0x6c [ 18.368673][ T301] mtk_iommu_probe_device+0xf8/0x118 [mtk_iommu] ... Cc: Robin Murphy Cc: Yong Wu Reported-by: kernel test robot Fixes: 635319a4a744 ("media: iommu/mediatek: Add device_link between the consumer and the larb devices") Signed-off-by: Miles Chen Reviewed-by: AngeloGioacchino Del Regno Reviewed-by: Yong Wu --- Change since v2 probe fail if larbdev is NULL so we do not have to worry about release logic Change since v1 fix a build warning reported by kernel test robot https://lore.kernel.org/lkml/202204231446.IYKdZ674-lkp@intel.com/ --- drivers/iommu/mtk_iommu.c | 6 ++++++ drivers/iommu/mtk_iommu_v1.c | 7 +++++++ 2 files changed, 13 insertions(+) diff --git a/drivers/iommu/mtk_iommu.c b/drivers/iommu/mtk_iommu.c index 6fd75a60abd6..155acfbce44f 100644 --- a/drivers/iommu/mtk_iommu.c +++ b/drivers/iommu/mtk_iommu.c @@ -572,6 +572,9 @@ static struct iommu_device *mtk_iommu_probe_device(struct device *dev) * All the ports in each a device should be in the same larbs. */ larbid = MTK_M4U_TO_LARB(fwspec->ids[0]); + if (larbid >= MTK_LARB_NR_MAX) + return ERR_PTR(-EINVAL); + for (i = 1; i < fwspec->num_ids; i++) { larbidx = MTK_M4U_TO_LARB(fwspec->ids[i]); if (larbid != larbidx) { @@ -581,6 +584,9 @@ static struct iommu_device *mtk_iommu_probe_device(struct device *dev) } } larbdev = data->larb_imu[larbid].dev; + if (!larbdev) + return ERR_PTR(-EINVAL); + link = device_link_add(dev, larbdev, DL_FLAG_PM_RUNTIME | DL_FLAG_STATELESS); if (!link) diff --git a/drivers/iommu/mtk_iommu_v1.c b/drivers/iommu/mtk_iommu_v1.c index ecff800656e6..74563f689fbd 100644 --- a/drivers/iommu/mtk_iommu_v1.c +++ b/drivers/iommu/mtk_iommu_v1.c @@ -80,6 +80,7 @@ /* MTK generation one iommu HW only support 4K size mapping */ #define MT2701_IOMMU_PAGE_SHIFT 12 #define MT2701_IOMMU_PAGE_SIZE (1UL << MT2701_IOMMU_PAGE_SHIFT) +#define MT2701_LARB_NR_MAX 3 /* * MTK m4u support 4GB iova address space, and only support 4K page @@ -457,6 +458,9 @@ static struct iommu_device *mtk_iommu_probe_device(struct device *dev) /* Link the consumer device with the smi-larb device(supplier) */ larbid = mt2701_m4u_to_larb(fwspec->ids[0]); + if (larbid >= MT2701_LARB_NR_MAX) + return ERR_PTR(-EINVAL); + for (idx = 1; idx < fwspec->num_ids; idx++) { larbidx = mt2701_m4u_to_larb(fwspec->ids[idx]); if (larbid != larbidx) { @@ -467,6 +471,9 @@ static struct iommu_device *mtk_iommu_probe_device(struct device *dev) } larbdev = data->larb_imu[larbid].dev; + if (!larbdev) + return ERR_PTR(-EINVAL); + link = device_link_add(dev, larbdev, DL_FLAG_PM_RUNTIME | DL_FLAG_STATELESS); if (!link)