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=-18.9 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,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 0F4FCC2B9F4 for ; Mon, 14 Jun 2021 11:01:52 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E7EB3613CC for ; Mon, 14 Jun 2021 11:01:51 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234395AbhFNLDu (ORCPT ); Mon, 14 Jun 2021 07:03:50 -0400 Received: from mail.kernel.org ([198.145.29.99]:60606 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234995AbhFNKy7 (ORCPT ); Mon, 14 Jun 2021 06:54:59 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id B117961419; Mon, 14 Jun 2021 10:40:27 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1623667228; bh=0yn5oIrFm35hUqC5US8/HECgH6nifrQYsV0i59dutGI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=LLOELfY6yKkM6TW3jRFU/KlGpcxckM5KLwOe2uL9PwyHCaC3eBX5XyHwCGaiL3zyl J/SX5LpsZXCRvnET8avzFWfQzUwsqT/nkwV51myMmmfokFBkXNSSPBmuFbzu8bV7j3 3/WlhlnRAGXHpD57X/MkisB3JnNLir3Y7QyPNHPk= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Anna Schumaker , Trond Myklebust Subject: [PATCH 5.4 76/84] NFS: Fix use-after-free in nfs4_init_client() Date: Mon, 14 Jun 2021 12:27:54 +0200 Message-Id: <20210614102648.951157140@linuxfoundation.org> X-Mailer: git-send-email 2.32.0 In-Reply-To: <20210614102646.341387537@linuxfoundation.org> References: <20210614102646.341387537@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Anna Schumaker commit 476bdb04c501fc64bf3b8464ffddefc8dbe01577 upstream. KASAN reports a use-after-free when attempting to mount two different exports through two different NICs that belong to the same server. Olga was able to hit this with kernels starting somewhere between 5.7 and 5.10, but I traced the patch that introduced the clear_bit() call to 4.13. So something must have changed in the refcounting of the clp pointer to make this call to nfs_put_client() the very last one. Fixes: 8dcbec6d20 ("NFSv41: Handle EXCHID4_FLAG_CONFIRMED_R during NFSv4.1 migration") Cc: stable@vger.kernel.org # 4.13+ Signed-off-by: Anna Schumaker Signed-off-by: Trond Myklebust Signed-off-by: Greg Kroah-Hartman --- fs/nfs/nfs4client.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/fs/nfs/nfs4client.c +++ b/fs/nfs/nfs4client.c @@ -435,8 +435,8 @@ struct nfs_client *nfs4_init_client(stru */ nfs_mark_client_ready(clp, -EPERM); } - nfs_put_client(clp); clear_bit(NFS_CS_TSM_POSSIBLE, &clp->cl_flags); + nfs_put_client(clp); return old; error: