From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751623AbdJXUCE (ORCPT ); Tue, 24 Oct 2017 16:02:04 -0400 Received: from mail.kernel.org ([198.145.29.99]:35236 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751280AbdJXUCB (ORCPT ); Tue, 24 Oct 2017 16:02:01 -0400 DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 117BD218AC Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=helgaas@kernel.org Date: Tue, 24 Oct 2017 15:02:00 -0500 From: Bjorn Helgaas To: Pankaj Dubey Cc: linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org, Kishon Vijay Abraham I , Bjorn Helgaas Subject: Re: [PATCH] PCI: endpoint: handle probable NULL pointer access Message-ID: <20171024200200.GE21840@bhelgaas-glaptop.roam.corp.google.com> References: <1507780677-7983-1-git-send-email-pankaj.dubey@samsung.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1507780677-7983-1-git-send-email-pankaj.dubey@samsung.com> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Oct 12, 2017 at 09:27:57AM +0530, Pankaj Dubey wrote: > controller_group allocation in pci_ep_cfs_init function can fail > so we should have a check while using it in pci_ep_cfs_add_epc_group > for registering group, else we will hit NULL pointer access. > > This patch adds required check for the same and returns -EPROBE_DEFER, > so that endpoint controller driver probe can be reattempted later > in case controller_group is not allocated because pci_ep_cfs_init is > not yet called. > > Signed-off-by: Pankaj Dubey Looking for Kishon's ack here. > --- > drivers/pci/endpoint/pci-ep-cfs.c | 7 ++++++- > drivers/pci/endpoint/pci-epc-core.c | 4 ++++ > 2 files changed, 10 insertions(+), 1 deletion(-) > > diff --git a/drivers/pci/endpoint/pci-ep-cfs.c b/drivers/pci/endpoint/pci-ep-cfs.c > index 424fdd6..3cac818 100644 > --- a/drivers/pci/endpoint/pci-ep-cfs.c > +++ b/drivers/pci/endpoint/pci-ep-cfs.c > @@ -172,7 +172,12 @@ struct config_group *pci_ep_cfs_add_epc_group(const char *name) > group = &epc_group->group; > > config_group_init_type_name(group, name, &pci_epc_type); > - ret = configfs_register_group(controllers_group, group); > + > + if (controllers_group) > + ret = configfs_register_group(controllers_group, group); > + else > + ret = -EPROBE_DEFER; > + > if (ret) { > pr_err("failed to register configfs group for %s\n", name); > goto err_register_group; > diff --git a/drivers/pci/endpoint/pci-epc-core.c b/drivers/pci/endpoint/pci-epc-core.c > index 42c2a11..d327a2a 100644 > --- a/drivers/pci/endpoint/pci-epc-core.c > +++ b/drivers/pci/endpoint/pci-epc-core.c > @@ -518,6 +518,10 @@ __pci_epc_create(struct device *dev, const struct pci_epc_ops *ops, > goto put_dev; > > epc->group = pci_ep_cfs_add_epc_group(dev_name(dev)); > + if (IS_ERR(epc->group)) { > + ret = -EPROBE_DEFER; > + goto put_dev; > + } > > return epc; > > -- > 2.7.4 >