From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 9EB537DA79; Wed, 11 Sep 2024 14:17:01 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1726064221; cv=none; b=D5pacA1E4wergKHiJMDypPZ4d0yZOIrwWsKz+g3YUOLjon9EzHIo/YIhgP6niivPsjtZVWBtmGpU/BTu09u5A2mG9ISTOFZ2pbN4s05AKmE+yMmN3L9hRFTtIjrGjOk/2wHiByygERsmPnMmr22yml8gDzvxWBmNhFNlEqR6cvs= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1726064221; c=relaxed/simple; bh=yjhgEM7kcYa6l2/+x2WzgcnyBOupWlUBMTKZvdp5avc=; h=Date:From:To:Cc:Subject:Message-ID:MIME-Version:Content-Type: Content-Disposition:In-Reply-To; b=TuSU3vCE0ZX3IlXCb1BcQmXGRIl44LcZjzUbIdRxU7Z13YeIzJBBSoZYYY38LT/xhgs4KRsSX41njw9bJL8w0nn9r0KZ31Jy7JgxaHLRD48BKt0WOlmRz2jpkvhbfSa+WUzYWFIuwKsUqLIyUYtR6ZSZBRdcMo5bxUHPXEp3AQw= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=iIJj4V/n; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="iIJj4V/n" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 902A4C4CEC0; Wed, 11 Sep 2024 14:17:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1726064221; bh=yjhgEM7kcYa6l2/+x2WzgcnyBOupWlUBMTKZvdp5avc=; h=Date:From:To:Cc:Subject:In-Reply-To:From; b=iIJj4V/nSbdat7JiCqwJEQ1K5SlkPq9tyWxNtNftGSyXn1U/YGKWqqysXFwVcm50P ZgJEScoMxrMKM5UyvUfNA/qMApGp+PtWOdYA3rFcN3+P33u/e0NXaJGR0Yj2gxeHPD t9yna94IzPaqDpAS6ErbhRpzJop1zwN3odszBLizqlGe38/D554FxujBfHoaNvKHl8 QYkdRwfqUasJT13meMgkPdKZgGHosRCy7Dl19WJjQx3K/jVd6/CW1GZi6pht9oY44R 5e8EBHidgA8ekjpDgz7Y1NhknXud9HssXkpFdYW4jJrDwMv16fzCAAtxPzKBIQI1D7 rp55lH2q1eY/Q== Date: Wed, 11 Sep 2024 09:16:58 -0500 From: Bjorn Helgaas To: Qianqiang Liu Cc: hongxing.zhu@nxp.com, l.stach@pengutronix.de, shawnguo@kernel.org, s.hauer@pengutronix.de, linux-pci@vger.kernel.org, imx@lists.linux.dev, linux-kernel@vger.kernel.org Subject: Re: [PATCH] PCI: imx6: Fix a "Null pointer dereference" issue Message-ID: <20240911141658.GA632894@bhelgaas> Precedence: bulk X-Mailing-List: linux-pci@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20240911125055.58555-1-qianqiang.liu@163.com> On Wed, Sep 11, 2024 at 08:50:57PM +0800, Qianqiang Liu wrote: > The "resource_list_first_type" function may return NULL, which > will make "entry->offset" dereferences a NULL pointer. > > Signed-off-by: Qianqiang Liu > --- > drivers/pci/controller/dwc/pci-imx6.c | 5 +++-- > 1 file changed, 3 insertions(+), 2 deletions(-) > > diff --git a/drivers/pci/controller/dwc/pci-imx6.c b/drivers/pci/controller/dwc/pci-imx6.c > index 0dbc333adcff..04e90ba4e7d6 100644 > --- a/drivers/pci/controller/dwc/pci-imx6.c > +++ b/drivers/pci/controller/dwc/pci-imx6.c > @@ -1017,13 +1017,14 @@ static u64 imx_pcie_cpu_addr_fixup(struct dw_pcie *pcie, u64 cpu_addr) > struct imx_pcie *imx_pcie = to_imx_pcie(pcie); > struct dw_pcie_rp *pp = &pcie->pp; > struct resource_entry *entry; > - unsigned int offset; > + unsigned int offset = 0; > > if (!(imx_pcie->drvdata->flags & IMX_PCIE_FLAG_CPU_ADDR_FIXUP)) > return cpu_addr; > > entry = resource_list_first_type(&pp->bridge->windows, IORESOURCE_MEM); > - offset = entry->offset; > + if (entry) > + offset = entry->offset; > > return (cpu_addr - offset); > } I made the edit I proposed here: https://lore.kernel.org/r/20240911140721.GA630378@bhelgaas Please double-check it at: https://git.kernel.org/pub/scm/linux/kernel/git/pci/pci.git/commit/?id=c2699778e6be