From patchwork Thu Mar 31 06:23:01 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Tony Lindgren X-Patchwork-Id: 12796772 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 06D9CC433EF for ; Thu, 31 Mar 2022 06:23:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230465AbiCaGZH (ORCPT ); Thu, 31 Mar 2022 02:25:07 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44084 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230463AbiCaGZG (ORCPT ); Thu, 31 Mar 2022 02:25:06 -0400 Received: from muru.com (muru.com [72.249.23.125]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id D1E1C1EC9A8 for ; Wed, 30 Mar 2022 23:23:19 -0700 (PDT) Received: from hillo.muru.com (localhost [127.0.0.1]) by muru.com (Postfix) with ESMTP id EBFAA80FA; Thu, 31 Mar 2022 06:21:08 +0000 (UTC) From: Tony Lindgren To: Joerg Roedel , Will Deacon Cc: Drew Fustini , Suman Anna , iommu@lists.linux-foundation.org, linux-arm-kernel@lists.infradead.org, linux-omap@vger.kernel.org, Lu Baolu , Jason Gunthorpe Subject: [PATCH] iommu/omap: Fix regression in probe for NULL pointer dereference Date: Thu, 31 Mar 2022 09:23:01 +0300 Message-Id: <20220331062301.24269-1-tony@atomide.com> X-Mailer: git-send-email 2.35.1 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-omap@vger.kernel.org Commit 3f6634d997db ("iommu: Use right way to retrieve iommu_ops") started triggering a NULL pointer dereference for some omap variants: __iommu_probe_device from probe_iommu_group+0x2c/0x38 probe_iommu_group from bus_for_each_dev+0x74/0xbc bus_for_each_dev from bus_iommu_probe+0x34/0x2e8 bus_iommu_probe from bus_set_iommu+0x80/0xc8 bus_set_iommu from omap_iommu_init+0x88/0xcc omap_iommu_init from do_one_initcall+0x44/0x24 This is caused by omap iommu probe returning 0 instead of ERR_PTR(-ENODEV) as noted by Jason Gunthorpe . Looks like the regression already happened with an earlier commit 6785eb9105e3 ("iommu/omap: Convert to probe/release_device() call-backs") that changed the function return type and missed converting one place. Cc: Drew Fustini Cc: Lu Baolu Cc: Suman Anna Suggested-by: Jason Gunthorpe Fixes: 6785eb9105e3 ("iommu/omap: Convert to probe/release_device() call-backs") Fixes: 3f6634d997db ("iommu: Use right way to retrieve iommu_ops") Signed-off-by: Tony Lindgren Reviewed-by: Jason Gunthorpe Tested-by: Drew Fustini --- drivers/iommu/omap-iommu.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/iommu/omap-iommu.c b/drivers/iommu/omap-iommu.c --- a/drivers/iommu/omap-iommu.c +++ b/drivers/iommu/omap-iommu.c @@ -1661,7 +1661,7 @@ static struct iommu_device *omap_iommu_probe_device(struct device *dev) num_iommus = of_property_count_elems_of_size(dev->of_node, "iommus", sizeof(phandle)); if (num_iommus < 0) - return 0; + return ERR_PTR(-ENODEV); arch_data = kcalloc(num_iommus + 1, sizeof(*arch_data), GFP_KERNEL); if (!arch_data)