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 8641823CE; Tue, 3 Dec 2024 16:04:48 +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=1733241888; cv=none; b=qHkq8LlkoNNlyd9Cx1oE/YfhtEm71hZt6L8VHZmPOrnoBpOaeplgHkz9T1f51bkK/FaYrpOUxFDnvFJ1jrrHET9xZ2FTY0+knPUAT7D01nDKZrV2oGHErvKYqANkiBuo3KHa7MFy25Tk0AFR+7JVR5yu2M8X8WPYpIl4lHHlbTY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1733241888; c=relaxed/simple; bh=PfWCZpqWlwY33BPic0cW9bdU0kAcfBG63b3ErhJ0bqY=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=I2yK8jJJ2F/42o16tkmCGzH19fGKE5Ty7Z/HJuiA0YRgVeHc5QOCBvmKQfTC1TjmiGQH4mnhsdlsEDvHjLp3k06PCDb08Jdby9bl9yKKGnAymtyOJ7vz+W5RZB05r1+Ralv/R6Ky8LGTTyovtvL5tslsxtvsFmEPlLSO2x3wpP0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=KHALDG0O; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="KHALDG0O" Received: by smtp.kernel.org (Postfix) with ESMTPSA id E3116C4CECF; Tue, 3 Dec 2024 16:04:47 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1733241888; bh=PfWCZpqWlwY33BPic0cW9bdU0kAcfBG63b3ErhJ0bqY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=KHALDG0ODvRWwqvLZRryGj+8hz3+pQWGoLcyOVfyygBzAz7C6WbzgWwcoB3Msu4+q 9LN7kdKMb0M9E09h1RayN5lS9rt3zNXk1GdXn5ECUL7YogTzkgG7ywz5pAOJXkXAN7 IWPLpHCt2YetaXGX1dEGdJ7ZHST0oq128j1o27Dk= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Dan Carpenter , Jeff Layton , Chuck Lever , Sasha Levin Subject: [PATCH 6.12 513/826] svcrdma: Address an integer overflow Date: Tue, 3 Dec 2024 15:44:00 +0100 Message-ID: <20241203144803.768272966@linuxfoundation.org> X-Mailer: git-send-email 2.47.1 In-Reply-To: <20241203144743.428732212@linuxfoundation.org> References: <20241203144743.428732212@linuxfoundation.org> User-Agent: quilt/0.67 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.12-stable review patch. If anyone has any objections, please let me know. ------------------ From: Chuck Lever [ Upstream commit 3c63d8946e578663b868cb9912dac616ea68bfd0 ] Dan Carpenter reports: > Commit 78147ca8b4a9 ("svcrdma: Add a "parsed chunk list" data > structure") from Jun 22, 2020 (linux-next), leads to the following > Smatch static checker warning: > > net/sunrpc/xprtrdma/svc_rdma_recvfrom.c:498 xdr_check_write_chunk() > warn: potential user controlled sizeof overflow 'segcount * 4 * 4' > > net/sunrpc/xprtrdma/svc_rdma_recvfrom.c > 488 static bool xdr_check_write_chunk(struct svc_rdma_recv_ctxt *rctxt) > 489 { > 490 u32 segcount; > 491 __be32 *p; > 492 > 493 if (xdr_stream_decode_u32(&rctxt->rc_stream, &segcount)) > ^^^^^^^^ > > 494 return false; > 495 > 496 /* A bogus segcount causes this buffer overflow check to fail. */ > 497 p = xdr_inline_decode(&rctxt->rc_stream, > --> 498 segcount * rpcrdma_segment_maxsz * sizeof(*p)); > > > segcount is an untrusted u32. On 32bit systems anything >= SIZE_MAX / 16 will > have an integer overflow and some those values will be accepted by > xdr_inline_decode(). Reported-by: Dan Carpenter Fixes: 78147ca8b4a9 ("svcrdma: Add a "parsed chunk list" data structure") Reviewed-by: Jeff Layton Signed-off-by: Chuck Lever Signed-off-by: Sasha Levin --- net/sunrpc/xprtrdma/svc_rdma_recvfrom.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/net/sunrpc/xprtrdma/svc_rdma_recvfrom.c b/net/sunrpc/xprtrdma/svc_rdma_recvfrom.c index ae3fb9bc8a216..292022f0976e1 100644 --- a/net/sunrpc/xprtrdma/svc_rdma_recvfrom.c +++ b/net/sunrpc/xprtrdma/svc_rdma_recvfrom.c @@ -493,7 +493,13 @@ static bool xdr_check_write_chunk(struct svc_rdma_recv_ctxt *rctxt) if (xdr_stream_decode_u32(&rctxt->rc_stream, &segcount)) return false; - /* A bogus segcount causes this buffer overflow check to fail. */ + /* Before trusting the segcount value enough to use it in + * a computation, perform a simple range check. This is an + * arbitrary but sensible limit (ie, not architectural). + */ + if (unlikely(segcount > RPCSVC_MAXPAGES)) + return false; + p = xdr_inline_decode(&rctxt->rc_stream, segcount * rpcrdma_segment_maxsz * sizeof(*p)); return p != NULL; -- 2.43.0