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 345B91F03D7; Tue, 4 Mar 2025 22:42:04 +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=1741128125; cv=none; b=S0P9ZQzYbfaxec4p4AJsxkVH7HhV4N0pieImyi/HZcam/ZfSzQRZcs8Oo91KiiF576qxtNf6vAnHfB2iXrKj2NYD99AZesMh5nSKM8mDwHTxo3RoHqyqBaVIKAVDa3qfiGSHqvQEjHZdTC0+Vdlp2UIIP3gVML7v1g58veBeqOk= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1741128125; c=relaxed/simple; bh=lVnymA60HmSZG+igOrN6c3CxYLXL85eQGfRLhLo9tU8=; h=Date:From:To:Cc:Subject:Message-ID:MIME-Version:Content-Type: Content-Disposition:In-Reply-To; b=gPtyrIIgaWLVIwbyPIAjHh4rGAYvCJV/C3gwXb1PbtxIkMIoNSJ9z2xseulzXbNFB0a752f6vkq2yZYt1Wzeej2SOsuIdx/UrF7cFgryz1uo0dSf49JxjQdYU9boV09jZrDffsEUvjUmipzcQ8v/DCPG0DQw9t5BDRwGEX0dQ6w= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=LXSUmnek; 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="LXSUmnek" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 909C6C4CEE5; Tue, 4 Mar 2025 22:42:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1741128124; bh=lVnymA60HmSZG+igOrN6c3CxYLXL85eQGfRLhLo9tU8=; h=Date:From:To:Cc:Subject:In-Reply-To:From; b=LXSUmnek0zRIOQ3Vwq8xRnAnSsU76SfnPjOM9g/zyVE/mZHl45099Sh6ATGV1U6cS 0zmvuUEBkqFQZKs6YbBLmi+uNN+rzxeMxMyqKMsa2HZJz38hrhXPG7L2Pp3tyikai0 oMV5uv/XBenF1FpDBh90ThH1FFkFH/R4XfS2RE/LX9sjglgl14beqR1zzGtS9b97D7 BPcI7EPu8kHkZNxbWRNcG3bnGc3e8eCWQWySeJt46fIbOIiN2Oo9Ln17MDohBmu91B p96J4R+RHP1H1rvPfR4tyYEf3tcn/rEFgkIEwRD5F1ourOiAsSMEpQYDw903H+SEQ6 svI03azfAeWuQ== Date: Tue, 4 Mar 2025 16:42:03 -0600 From: Bjorn Helgaas To: Philipp Stanner Cc: Bjorn Helgaas , linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org, Bingbu Cao Subject: Re: [PATCH] PCI: Check BAR index for validity Message-ID: <20250304224203.GA260968@bhelgaas> Precedence: bulk X-Mailing-List: linux-kernel@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: <20250304143112.104190-2-phasta@kernel.org> On Tue, Mar 04, 2025 at 03:31:13PM +0100, Philipp Stanner wrote: > Many functions in PCI use accessor macros such as pci_resource_len(), > which take a BAR index. That index, however, is never checked for > validity, potentially resulting in undefined behavior by overflowing the > array pci_dev.resource in the macro pci_resource_n(). > > Since many users of those macros directly assign the accessed value to > an unsigned integer, the macros cannot be changed easily anymore to > return -EINVAL for invalid indexes. Consequently, the problem has to be > mitigated in higher layers. > > Add pci_bar_index_valid(). Use it where appropriate. > > Reported-by: Bingbu Cao > Closes: https://lore.kernel.org/all/adb53b1f-29e1-3d14-0e61-351fd2d3ff0d@linux.intel.com/ > Signed-off-by: Philipp Stanner Applied to pci/devres for v6.15, thanks. I reversed this: > +static inline bool pci_bar_index_is_valid(int bar) > +{ > + if (bar < 0 || bar >= PCI_NUM_RESOURCES) > + return false; > + > + return true; > +} so the test describes valid indexes, not invalid ones: if (bar >= 0 && bar < PCI_NUM_RESOURCES) return true; return false;