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 5AA8E28EE for ; Mon, 2 Jan 2023 11:25:06 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id D222EC433D2; Mon, 2 Jan 2023 11:25:05 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1672658706; bh=5ESaYueSwS0c6WXjWuORuylx//yXLV5QlYjDpSx3YQ8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=paJ7jaunRViA7SAynQkPrd/SqTHP9ZkQipTTwUc6I8zKX64adIkkZmg8rCqV4mk5j WZigLQDAtTlgQeLPk+CKH8YO44PiUTCzN8tdaYxathdB/6fXw/spFFEB+uEPQi5XC5 zkWUSn+uzQnYR+T5vAFWkwIisnL4Ca0LIc3Q2w98= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Xingyuan Mo , Dai Ngo , Chuck Lever , Sasha Levin Subject: [PATCH 6.1 38/71] NFSD: fix use-after-free in __nfs42_ssc_open() Date: Mon, 2 Jan 2023 12:22:03 +0100 Message-Id: <20230102110553.067559977@linuxfoundation.org> X-Mailer: git-send-email 2.39.0 In-Reply-To: <20230102110551.509937186@linuxfoundation.org> References: <20230102110551.509937186@linuxfoundation.org> User-Agent: quilt/0.67 Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit From: Dai Ngo [ Upstream commit 75333d48f92256a0dec91dbf07835e804fc411c0 ] Problem caused by source's vfsmount being unmounted but remains on the delayed unmount list. This happens when nfs42_ssc_open() return errors. Fixed by removing nfsd4_interssc_connect(), leave the vfsmount for the laundromat to unmount when idle time expires. We don't need to call nfs_do_sb_deactive when nfs42_ssc_open return errors since the file was not opened so nfs_server->active was not incremented. Same as in nfsd4_copy, if we fail to launch nfsd4_do_async_copy thread then there's no need to call nfs_do_sb_deactive Reported-by: Xingyuan Mo Signed-off-by: Dai Ngo Tested-by: Xingyuan Mo Signed-off-by: Chuck Lever Signed-off-by: Sasha Levin --- fs/nfsd/nfs4proc.c | 20 +++++--------------- 1 file changed, 5 insertions(+), 15 deletions(-) diff --git a/fs/nfsd/nfs4proc.c b/fs/nfsd/nfs4proc.c index 32fe7cbfb28b..34d1cd5883fb 100644 --- a/fs/nfsd/nfs4proc.c +++ b/fs/nfsd/nfs4proc.c @@ -1465,13 +1465,6 @@ nfsd4_interssc_connect(struct nl4_server *nss, struct svc_rqst *rqstp, return status; } -static void -nfsd4_interssc_disconnect(struct vfsmount *ss_mnt) -{ - nfs_do_sb_deactive(ss_mnt->mnt_sb); - mntput(ss_mnt); -} - /* * Verify COPY destination stateid. * @@ -1574,11 +1567,6 @@ nfsd4_cleanup_inter_ssc(struct vfsmount *ss_mnt, struct file *filp, { } -static void -nfsd4_interssc_disconnect(struct vfsmount *ss_mnt) -{ -} - static struct file *nfs42_ssc_open(struct vfsmount *ss_mnt, struct nfs_fh *src_fh, nfs4_stateid *stateid) @@ -1774,7 +1762,7 @@ static int nfsd4_do_async_copy(void *data) default: nfserr = nfserr_offload_denied; } - nfsd4_interssc_disconnect(copy->ss_mnt); + /* ss_mnt will be unmounted by the laundromat */ goto do_callback; } nfserr = nfsd4_do_copy(copy, filp, copy->nf_dst->nf_file, @@ -1855,8 +1843,10 @@ nfsd4_copy(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate, if (async_copy) cleanup_async_copy(async_copy); status = nfserrno(-ENOMEM); - if (nfsd4_ssc_is_inter(copy)) - nfsd4_interssc_disconnect(copy->ss_mnt); + /* + * source's vfsmount of inter-copy will be unmounted + * by the laundromat + */ goto out; } -- 2.35.1