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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 5283FC678D4 for ; Tue, 7 Mar 2023 17:34:12 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231749AbjCGReL (ORCPT ); Tue, 7 Mar 2023 12:34:11 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33238 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231426AbjCGRdw (ORCPT ); Tue, 7 Mar 2023 12:33:52 -0500 Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6EC239CFC5 for ; Tue, 7 Mar 2023 09:29:24 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 13BBBB819AB for ; Tue, 7 Mar 2023 17:29:23 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 4BCDFC433EF; Tue, 7 Mar 2023 17:29:21 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1678210161; bh=7gqh2N3Os5LFfKO1I2aB9zj0npN4q/VBQicsSbaUyKk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=xgVnCS665/ADXxcZPpjfErIPpu76ctWVidxJUZHycg/Ur6h7v6BCsywm6y3NRZ0iW Dcew4yjL9HZsEryUKWuKsyGVpmn5Zfk4nIxSrWQU77nHHHSSUrUgqPpydUiH2jnDUQ d6GB+OGsnqpQaM6paAdGskSUV/INPymFnR61Sd9o= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Jeff Layton , Chuck Lever , Sasha Levin Subject: [PATCH 6.2 0452/1001] nfsd: clean up potential nfsd_file refcount leaks in COPY codepath Date: Tue, 7 Mar 2023 17:53:44 +0100 Message-Id: <20230307170040.964428592@linuxfoundation.org> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20230307170022.094103862@linuxfoundation.org> References: <20230307170022.094103862@linuxfoundation.org> User-Agent: quilt/0.67 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Jeff Layton [ Upstream commit 6ba434cb1a8d403ea9aad1b667c3ea3ad8b3191f ] There are two different flavors of the nfsd4_copy struct. One is embedded in the compound and is used directly in synchronous copies. The other is dynamically allocated, refcounted and tracked in the client struture. For the embedded one, the cleanup just involves releasing any nfsd_files held on its behalf. For the async one, the cleanup is a bit more involved, and we need to dequeue it from lists, unhash it, etc. There is at least one potential refcount leak in this code now. If the kthread_create call fails, then both the src and dst nfsd_files in the original nfsd4_copy object are leaked. The cleanup in this codepath is also sort of weird. In the async copy case, we'll have up to four nfsd_file references (src and dst for both flavors of copy structure). They are both put at the end of nfsd4_do_async_copy, even though the ones held on behalf of the embedded one outlive that structure. Change it so that we always clean up the nfsd_file refs held by the embedded copy structure before nfsd4_copy returns. Rework cleanup_async_copy to handle both inter and intra copies. Eliminate nfsd4_cleanup_intra_ssc since it now becomes a no-op. Signed-off-by: Jeff Layton Signed-off-by: Chuck Lever Stable-dep-of: 81e722978ad2 ("NFSD: fix problems with cleanup on errors in nfsd4_copy") Signed-off-by: Sasha Levin --- fs/nfsd/nfs4proc.c | 23 ++++++++++------------- 1 file changed, 10 insertions(+), 13 deletions(-) diff --git a/fs/nfsd/nfs4proc.c b/fs/nfsd/nfs4proc.c index e2dde8a1837be..b74cbc9a0e7f3 100644 --- a/fs/nfsd/nfs4proc.c +++ b/fs/nfsd/nfs4proc.c @@ -1510,7 +1510,6 @@ nfsd4_cleanup_inter_ssc(struct nfsd4_ssc_umount_item *nsui, struct file *filp, long timeout = msecs_to_jiffies(nfsd4_ssc_umount_timeout); nfs42_ssc_close(filp); - nfsd_file_put(dst); fput(filp); spin_lock(&nn->nfsd_ssc_lock); @@ -1560,13 +1559,6 @@ nfsd4_setup_intra_ssc(struct svc_rqst *rqstp, ©->nf_dst); } -static void -nfsd4_cleanup_intra_ssc(struct nfsd_file *src, struct nfsd_file *dst) -{ - nfsd_file_put(src); - nfsd_file_put(dst); -} - static void nfsd4_cb_offload_release(struct nfsd4_callback *cb) { struct nfsd4_cb_offload *cbo = @@ -1681,12 +1673,18 @@ static void dup_copy_fields(struct nfsd4_copy *src, struct nfsd4_copy *dst) dst->ss_nsui = src->ss_nsui; } +static void release_copy_files(struct nfsd4_copy *copy) +{ + if (copy->nf_src) + nfsd_file_put(copy->nf_src); + if (copy->nf_dst) + nfsd_file_put(copy->nf_dst); +} + static void cleanup_async_copy(struct nfsd4_copy *copy) { nfs4_free_copy_state(copy); - nfsd_file_put(copy->nf_dst); - if (!nfsd4_ssc_is_inter(copy)) - nfsd_file_put(copy->nf_src); + release_copy_files(copy); spin_lock(©->cp_clp->async_lock); list_del(©->copies); spin_unlock(©->cp_clp->async_lock); @@ -1746,7 +1744,6 @@ static int nfsd4_do_async_copy(void *data) } else { nfserr = nfsd4_do_copy(copy, copy->nf_src->nf_file, copy->nf_dst->nf_file, false); - nfsd4_cleanup_intra_ssc(copy->nf_src, copy->nf_dst); } do_callback: @@ -1809,9 +1806,9 @@ nfsd4_copy(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate, } else { status = nfsd4_do_copy(copy, copy->nf_src->nf_file, copy->nf_dst->nf_file, true); - nfsd4_cleanup_intra_ssc(copy->nf_src, copy->nf_dst); } out: + release_copy_files(copy); return status; out_err: if (nfsd4_ssc_is_inter(copy)) { -- 2.39.2