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=-19.2 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,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 10C41C433F2 for ; Thu, 25 Mar 2021 11:30:24 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C41CD61A4D for ; Thu, 25 Mar 2021 11:30:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230479AbhCYL3w (ORCPT ); Thu, 25 Mar 2021 07:29:52 -0400 Received: from mail.kernel.org ([198.145.29.99]:35196 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230156AbhCYL1X (ORCPT ); Thu, 25 Mar 2021 07:27:23 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 3EE0661A4D; Thu, 25 Mar 2021 11:26:56 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1616671617; bh=aSsv+3NmE3Tzx3SVHv1jckw8Y0Vuo4ZP0QyKCcKjMAk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=B3zeBR1uM+4lu3hMPs5tCqAdlOTeW52v6UiHYpi0PA5Boou52l/Q1h3q3EvRa4JhN 2eQBB1VSsuBdy/zVTJ3mfmiIWg8PyK2DS9z/OQ9j/ozG+hrq1zvDQkU04zw2VdlUfv /y+Z4ZJMii9H+e6U+S2O3xdM0Od9opzCfLfFZm9Z89WfdtWXN5SH/Dj5+ApPOX3ba4 0UstjqxtrhqBIVpd3JzOdgRtae2OUKGcAx2lQir2Oruqa0Y/VzStTxhTkT6xj0dFwv RI8mqyY3RZK1IgbhKt3Rqu08VaqlRL4MWD1qFry/FZayIAAc5b4WC2YUzDdIAtl/a4 Z2C+qiEVayrrg== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: "J. Bruce Fields" , Chuck Lever , Sasha Levin , linux-nfs@vger.kernel.org, netdev@vger.kernel.org Subject: [PATCH AUTOSEL 5.4 04/24] rpc: fix NULL dereference on kmalloc failure Date: Thu, 25 Mar 2021 07:26:30 -0400 Message-Id: <20210325112651.1927828-4-sashal@kernel.org> X-Mailer: git-send-email 2.30.1 In-Reply-To: <20210325112651.1927828-1-sashal@kernel.org> References: <20210325112651.1927828-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org From: "J. Bruce Fields" [ Upstream commit 0ddc942394013f08992fc379ca04cffacbbe3dae ] I think this is unlikely but possible: svc_authenticate sets rq_authop and calls svcauth_gss_accept. The kmalloc(sizeof(*svcdata), GFP_KERNEL) fails, leaving rq_auth_data NULL, and returning SVC_DENIED. This causes svc_process_common to go to err_bad_auth, and eventually call svc_authorise. That calls ->release == svcauth_gss_release, which tries to dereference rq_auth_data. Signed-off-by: J. Bruce Fields Link: https://lore.kernel.org/linux-nfs/3F1B347F-B809-478F-A1E9-0BE98E22B0F0@oracle.com/T/#t Signed-off-by: Chuck Lever Signed-off-by: Sasha Levin --- net/sunrpc/auth_gss/svcauth_gss.c | 11 +++++++---- 1 file changed, 7 insertions(+), 4 deletions(-) diff --git a/net/sunrpc/auth_gss/svcauth_gss.c b/net/sunrpc/auth_gss/svcauth_gss.c index cf4d6d7e7282..d5470c7fe879 100644 --- a/net/sunrpc/auth_gss/svcauth_gss.c +++ b/net/sunrpc/auth_gss/svcauth_gss.c @@ -1782,11 +1782,14 @@ static int svcauth_gss_release(struct svc_rqst *rqstp) { struct gss_svc_data *gsd = (struct gss_svc_data *)rqstp->rq_auth_data; - struct rpc_gss_wire_cred *gc = &gsd->clcred; + struct rpc_gss_wire_cred *gc; struct xdr_buf *resbuf = &rqstp->rq_res; int stat = -EINVAL; struct sunrpc_net *sn = net_generic(SVC_NET(rqstp), sunrpc_net_id); + if (!gsd) + goto out; + gc = &gsd->clcred; if (gc->gc_proc != RPC_GSS_PROC_DATA) goto out; /* Release can be called twice, but we only wrap once. */ @@ -1827,10 +1830,10 @@ svcauth_gss_release(struct svc_rqst *rqstp) if (rqstp->rq_cred.cr_group_info) put_group_info(rqstp->rq_cred.cr_group_info); rqstp->rq_cred.cr_group_info = NULL; - if (gsd->rsci) + if (gsd && gsd->rsci) { cache_put(&gsd->rsci->h, sn->rsc_cache); - gsd->rsci = NULL; - + gsd->rsci = NULL; + } return stat; } -- 2.30.1