From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id B4B25C32771 for ; Fri, 24 Jan 2020 11:25:29 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 7F1792077C for ; Fri, 24 Jan 2020 11:25:29 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1579865129; bh=RPzwxGdZF9QySgEMfxCOhhZh9G/v8Z9PCoqv92S5mds=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=c3m1NjB3YT2Dn4Grq9bONJoNTxKKlVgAKdwOdxRrx+w9ur4/5CGuB/v/E54Hn5RVH cQIxDFlgecm0hGJpI06xIPsmwtUDdzikhitXLNo3wQXModuXkn/2cBg7/oF1GuCSrR 3w3DnVwLVxz1rVTiPGcDrjdUzkDVi61OHmAeuESM= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2391498AbgAXLZ2 (ORCPT ); Fri, 24 Jan 2020 06:25:28 -0500 Received: from mail.kernel.org ([198.145.29.99]:39474 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2391471AbgAXLZZ (ORCPT ); Fri, 24 Jan 2020 06:25:25 -0500 Received: from localhost (ip-213-127-102-57.ip.prioritytelecom.net [213.127.102.57]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 72ACC222C2; Fri, 24 Jan 2020 11:25:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1579865124; bh=RPzwxGdZF9QySgEMfxCOhhZh9G/v8Z9PCoqv92S5mds=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=wxxgv6u6WfdXayFvHift5iJbagSk2VpA6fF3qi56FUFFE96N9CQ5rFn+qFwssjdGH /ULdnFEEziU5Wkpld7uSLuXUAVsZX2vyx9m3Rb4MpRSNTGfxTOneZr9X3ovsdnDysc O8VE65Y/5EIIoqchrpg6N1Wz89qYc8y2ZbcNIfYY= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Chuck Lever , Anna Schumaker , Sasha Levin Subject: [PATCH 4.19 460/639] xprtrdma: Fix use-after-free in rpcrdma_post_recvs Date: Fri, 24 Jan 2020 10:30:30 +0100 Message-Id: <20200124093144.844734045@linuxfoundation.org> X-Mailer: git-send-email 2.25.0 In-Reply-To: <20200124093047.008739095@linuxfoundation.org> References: <20200124093047.008739095@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Chuck Lever [ Upstream commit 2d0abe36cf13fb7b577949fd1539326adddcc9bc ] Dereference wr->next /before/ the memory backing wr has been released. This issue was found by code inspection. It is not expected to be a significant problem because it is in an error path that is almost never executed. Fixes: 7c8d9e7c8863 ("xprtrdma: Move Receive posting to ... ") Signed-off-by: Chuck Lever Signed-off-by: Anna Schumaker Signed-off-by: Sasha Levin --- net/sunrpc/xprtrdma/verbs.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/net/sunrpc/xprtrdma/verbs.c b/net/sunrpc/xprtrdma/verbs.c index 90ec322dbbc0f..ef1f3d076af96 100644 --- a/net/sunrpc/xprtrdma/verbs.c +++ b/net/sunrpc/xprtrdma/verbs.c @@ -1558,10 +1558,11 @@ rpcrdma_post_recvs(struct rpcrdma_xprt *r_xprt, bool temp) rc = ib_post_recv(r_xprt->rx_ia.ri_id->qp, wr, (const struct ib_recv_wr **)&bad_wr); if (rc) { - for (wr = bad_wr; wr; wr = wr->next) { + for (wr = bad_wr; wr;) { struct rpcrdma_rep *rep; rep = container_of(wr, struct rpcrdma_rep, rr_recv_wr); + wr = wr->next; rpcrdma_recv_buffer_put(rep); --count; } -- 2.20.1