From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 C00B937E5F6; Thu, 16 Jul 2026 21:50:37 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784238638; cv=none; b=Vu7biPieJLy+gj68a+XYivCXnlr3ufDp7Ex33xXGHrIYyKLjKhadwYRvaIgLJ7f9yUTx2D4rfAS5MvrBMkV0UHYP/u8eDknNHMRdDjLrgK9TpMVLbbzj1NFfNPZZqsmaifoXiOvzPHCnn/A3vcMVq5wWXo7rZm9OkJwPO6JTdt0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784238638; c=relaxed/simple; bh=V2Vr7s5c/DktYXLwFcpnq4Xzb0Lv1MO3jn1dqzr24CU=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=ovz9RmHlaLKNZOLmIn8UG4YrjkDIo/3WrnWO1TmQvezbZZLFgzm3+lLxMYZne4aLfbmizZq1QRZsZMsccX2BL1Gp3iQiVDxDv/HpAf+s2HHeKYrDv81MWX+kJKukAgovEsLBbFe9p3YLPaaXmeR4kn/GX1WQYdQ99nxO51OTGZQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=h6Jjh3s/; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="h6Jjh3s/" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 794861F000E9; Thu, 16 Jul 2026 21:50:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1784238637; bh=On59Ed+6z5FwuPewVYmVjD+eEBTPHmsepnmu8ecs534=; h=Date:Subject:To:Cc:References:From:In-Reply-To; b=h6Jjh3s/LxycVmB2yN0V6QXNkHXJ+bEXH2VPxBUoyZgIz1q1YyaAdZIQAUivqyao0 +beNYCJs4iWLjr2o+4Iuk7mOMWGkTtuluBTalQeDAmxgROAO/1UrUI/HyADf7NgwbP xYaP0/9pUXhOMNbAFWe0SIXKIB/dNCekHLLZW4IXAp+GOEQtCgMYzcQJKh3qIV7TH5 bnSXbWsJKeNW6ISqKom6T7bE752N9nyjlWciWunTL1C/3T+eW9xcf6RBj/7ofEbBf1 Z6SDJ8GWqcs3zSCkSRApnXGeftYnhXOLy0XZB/NaP3I3Qd1m2ADIOGU8WUOFtCm6gS TDf0pP1oWU+9Q== Message-ID: <082227b8-7df9-4d0e-8ec9-c0e3cb751a78@kernel.org> Date: Thu, 16 Jul 2026 22:50:35 +0100 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH] nvmem: brcm_nvram: validate cached NVRAM length To: Pengpeng Hou , srini@kernel.org Cc: rafal@milecki.pl, linux-kernel@vger.kernel.org, stable@vger.kernel.org References: <20260715084504.43774-1-pengpeng@iscas.ac.cn> Content-Language: en-US From: Srinivas Kandagatla In-Reply-To: <20260715084504.43774-1-pengpeng@iscas.ac.cn> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit On 7/15/26 9:45 AM, Pengpeng Hou wrote: > The cached-content conversion stops at the partition padding. Therefore, > data_len may be smaller than nvmem_size. brcm_nvram_parse() checks > header->len against nvmem_size, then passes that length to > brcm_nvram_add_cells(), which temporarily writes data[len - 1] and parses > NUL-separated entries. > > A corrupted header can declare a length that fits the MMIO resource but > exceeds the cached allocation. Also reject a cached object that is too > small for the header, and reject declared lengths shorter than the header. > > Validate the declaration against data_len, which bounds the parsed object. > > Fixes: 1e37bf84afac ("nvmem: brcm_nvram: store a copy of NVRAM content") > Cc: stable@vger.kernel.org > Signed-off-by: Pengpeng Hou There are already few patches on the list which are doing pretty much same changes, i have applied them which should appear in linux-next in a day. https://lkml.org/lkml/2026/7/3/2291 --srini > --- > drivers/nvmem/brcm_nvram.c | 12 +++++++++--- > 1 file changed, 9 insertions(+), 3 deletions(-) > > diff --git a/drivers/nvmem/brcm_nvram.c b/drivers/nvmem/brcm_nvram.c > index aaa6537798bf..4701772cfa47 100644 > --- a/drivers/nvmem/brcm_nvram.c > +++ b/drivers/nvmem/brcm_nvram.c > @@ -181,15 +181,21 @@ static int brcm_nvram_parse(struct brcm_nvram *priv) > size_t len; > int err; > > + if (priv->data_len < sizeof(*header)) { > + dev_err(dev, "NVRAM content (%zu) is smaller than header (%zu)\n", > + priv->data_len, sizeof(*header)); > + return -EINVAL; > + } > + > if (memcmp(header->magic, NVRAM_MAGIC, 4)) { > dev_err(dev, "Invalid NVRAM magic\n"); > return -EINVAL; > } > > len = le32_to_cpu(header->len); > - if (len > priv->nvmem_size) { > - dev_err(dev, "NVRAM length (%zd) exceeds mapped size (%zd)\n", len, > - priv->nvmem_size); > + if (len < sizeof(*header) || len > priv->data_len) { > + dev_err(dev, "NVRAM length (%zu) is outside cached content (%zu)\n", > + len, priv->data_len); > return -EINVAL; > } >