From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752201AbeB0QNF (ORCPT ); Tue, 27 Feb 2018 11:13:05 -0500 Received: from mail-qk0-f194.google.com ([209.85.220.194]:39526 "EHLO mail-qk0-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751004AbeB0QND (ORCPT ); Tue, 27 Feb 2018 11:13:03 -0500 X-Google-Smtp-Source: AG47ELuLNaShWzunRzyNDUKO2JH8u6kkyMfInaJFJngZs6GvR/ZF2kJqc7h2JV3BtFkBuxoQmkHgsW5ad3hREWjICKk= MIME-Version: 1.0 In-Reply-To: <20180227100231.22561-1-embedded24@evers-fischer.de> References: <20180227100231.22561-1-embedded24@evers-fischer.de> From: Andy Shevchenko Date: Tue, 27 Feb 2018 18:13:02 +0200 Message-ID: Subject: Re: [PATCH v3 0/2] pci: endpoint: Fix double free in pci_epf_create() To: Rolf Evers-Fischer Cc: Kishon Vijay Abraham I , Lorenzo Pieralisi , Bjorn Helgaas , linux-pci@vger.kernel.org, Linux Kernel Mailing List Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Feb 27, 2018 at 12:02 PM, Rolf Evers-Fischer wrote: > This is version 3 of a patchset to avoid double free in function > 'pci_epf_create()'. > > When I accidentally created a new endpoint device with an empty name, > the kernel warned about "attempted to be registered with empty name!" > and crashed afterwards. > > It turned out that the crash was not caused by the 'device_add()' > function itself, but by a double kfree of 'epf->name' and 'epf'. > > The first patch just simplifies the code, while the second patch > fixes the problem. > After addressing Bjorn's comments, FWIW, Reviewed-by: Andy Shevchenko > Changes in v3: > - Matched to other pending pci endpoint commits (thanks, Bjorn!) > - Added "Fixes" tag in patch 2 (thanks, Andy!) > > Changes in v2: > - Based on feedback from Lorenzo, Andy and Kishon (thanks!) > - Change IDs removed > - First patch completely reworked in order to eliminate the > need for the second 'kstrdup' allocation and the 'kfree' of > the first allocation. > It was tested with name="pci_epf_test.0" and name="pci_epb": > The 'epf->name' was "pci_epf_test" or "pci_epb" (=unchanged). > > Rolf Evers-Fischer (2): > pci: endpoint: Simplify name allocation for epf device > pci: endpoint: Fix kernel panic after put_device() > > drivers/pci/endpoint/pci-epf-core.c | 24 +++++------------------- > 1 file changed, 5 insertions(+), 19 deletions(-) > > -- > 2.16.2 > -- With Best Regards, Andy Shevchenko