From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from verein.lst.de (verein.lst.de [213.95.11.211]) (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 610903CCA02 for ; Mon, 20 Jul 2026 08:24:02 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=213.95.11.211 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784535843; cv=none; b=ausr5+jBXu3+bT1/3qOjcHxPTRob19eupvvU695kFuoagToxfdapYHCn2HBE1SclbL21WLoaUhEHPdnRekPjG5TEx38kMVA6XZMIf2ggmAREpdx0erkdQ70CZC4yE97ZJFCsorY/KqB/2EYlnyxrrh9j4ndPkGloP98f3OuyvD8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784535843; c=relaxed/simple; bh=Bwdmq1oL2d/ZuutU0brpfWB4M/9iVEa9lTnVgCaht8k=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=JMmTgSWqInkN8gOXXFxOT45lQAK97q0f3eUsRudeQ2LIbb2Z4T/aiRsleEpMhwfu3GQRZjGvaUhnukgo63eUlnJ9Jv1OOim+FJyGpQYbFREJsRV/PAhwnmXr1amFmcpyxTCDPyyCbkVp/kE7ig2cjCJJGOgm331K7Wx8nJrFF5M= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=lst.de; spf=pass smtp.mailfrom=lst.de; arc=none smtp.client-ip=213.95.11.211 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=lst.de Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=lst.de Received: by verein.lst.de (Postfix, from userid 2407) id 4672568D32; Mon, 20 Jul 2026 10:23:56 +0200 (CEST) Date: Mon, 20 Jul 2026 10:23:55 +0200 From: Christoph Hellwig To: Hari Mishal Cc: Christoph Hellwig , Sagi Grimberg , Chaitanya Kulkarni , linux-nvme@lists.infradead.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] nvmet: passthru: fix OOB reads when parsing ns id descriptor list Message-ID: <20260720082355.GA20499@lst.de> References: <20260717144353.19436-1-harimishal1@gmail.com> 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: <20260717144353.19436-1-harimishal1@gmail.com> User-Agent: Mutt/1.5.17 (2007-11-01) On Fri, Jul 17, 2026 at 04:43:53PM +0200, Hari Mishal wrote: > nvmet_passthru_override_id_descs() walks a namespace identification > descriptor list populated from the underlying passthru controller's > Identify response, which is device reported. The loop advanced pos by > device controlled amounts (sizeof(*cur) + nidl) without checking that > the next descriptor header actually fits inside the buffer, so a > malicious device could push pos to within a few bytes of the buffer end > and cause cur->nidl, cur->nidt or the reserved field to be read past the > allocation. > > Additionally, when a CSI descriptor lands exactly at the last valid > header offset, cur + 1 points one byte past the end of the buffer. > The unconditional memcpy(&csi, cur + 1, NVME_NIDT_CSI_LEN) could read > that out-of-bounds byte and copy it back to the initiator via > nvmet_copy_to_sgl(), leaking adjacent heap memory. > > Bounds check both the descriptor header and the CSI value before > dereferencing them. > > Signed-off-by: Hari Mishal > --- > drivers/nvme/target/passthru.c | 8 ++++++++ > 1 file changed, 8 insertions(+) > > diff --git a/drivers/nvme/target/passthru.c b/drivers/nvme/target/passthru.c > index e27f84e3cf2b..7ef02958078b 100644 > --- a/drivers/nvme/target/passthru.c > +++ b/drivers/nvme/target/passthru.c > @@ -53,13 +53,21 @@ static u16 nvmet_passthru_override_id_descs(struct nvmet_req *req) > for (pos = 0; pos < NVME_IDENTIFY_DATA_SIZE; pos += len) { > struct nvme_ns_id_desc *cur = data + pos; > > + if (pos + sizeof(*cur) > NVME_IDENTIFY_DATA_SIZE) > + break; > + > if (cur->nidl == 0) > break; > + > if (cur->nidt == NVME_NIDT_CSI) { > + if (pos + sizeof(*cur) + NVME_NIDT_CSI_LEN > NVME_IDENTIFY_DATA_SIZE) Overly long line here. Otherwise this looks sane.