From patchwork Fri Sep 6 06:54:07 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Michael Tokarev X-Patchwork-Id: 13793458 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 lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 91856CE7AB9 for ; Fri, 6 Sep 2024 06:59:32 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1smSvQ-0008HG-54; Fri, 06 Sep 2024 02:58:33 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1smSup-000502-5t; Fri, 06 Sep 2024 02:57:55 -0400 Received: from isrv.corpit.ru ([86.62.121.231]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1smSul-0003a7-DQ; Fri, 06 Sep 2024 02:57:54 -0400 Received: from tsrv.corpit.ru (tsrv.tls.msk.ru [192.168.177.2]) by isrv.corpit.ru (Postfix) with ESMTP id 19D618C25A; Fri, 6 Sep 2024 09:53:14 +0300 (MSK) Received: from tls.msk.ru (mjt.wg.tls.msk.ru [192.168.177.130]) by tsrv.corpit.ru (Postfix) with SMTP id D4D40133412; Fri, 6 Sep 2024 09:54:31 +0300 (MSK) Received: (nullmailer pid 43621 invoked by uid 1000); Fri, 06 Sep 2024 06:54:30 -0000 From: Michael Tokarev To: qemu-devel@nongnu.org Cc: qemu-stable@nongnu.org, Eric Blake , Vladimir Sementsov-Ogievskiy , =?utf-8?q?Daniel_?= =?utf-8?q?P_=2E_Berrang=C3=A9?= , Michael Tokarev Subject: [Stable-8.2.7 37/53] nbd/server: Plumb in new args to nbd_client_add() Date: Fri, 6 Sep 2024 09:54:07 +0300 Message-Id: <20240906065429.42415-37-mjt@tls.msk.ru> X-Mailer: git-send-email 2.39.2 In-Reply-To: References: MIME-Version: 1.0 Received-SPF: pass client-ip=86.62.121.231; envelope-from=mjt@tls.msk.ru; helo=isrv.corpit.ru X-Spam_score_int: -68 X-Spam_score: -6.9 X-Spam_bar: ------ X-Spam_report: (-6.9 / 5.0 requ) BAYES_00=-1.9, RCVD_IN_DNSWL_HI=-5, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org From: Eric Blake Upcoming patches to fix a CVE need to track an opaque pointer passed in by the owner of a client object, as well as request for a time limit on how fast negotiation must complete. Prepare for that by changing the signature of nbd_client_new() and adding an accessor to get at the opaque pointer, although for now the two servers (qemu-nbd.c and blockdev-nbd.c) do not change behavior even though they pass in a new default timeout value. Suggested-by: Vladimir Sementsov-Ogievskiy Signed-off-by: Eric Blake Message-ID: <20240807174943.771624-11-eblake@redhat.com> Reviewed-by: Daniel P. Berrangé [eblake: s/LIMIT/MAX_SECS/ as suggested by Dan] Signed-off-by: Eric Blake (cherry picked from commit fb1c2aaa981e0a2fa6362c9985f1296b74f055ac) Signed-off-by: Michael Tokarev diff --git a/blockdev-nbd.c b/blockdev-nbd.c index 213012435f..267a1de903 100644 --- a/blockdev-nbd.c +++ b/blockdev-nbd.c @@ -64,8 +64,10 @@ static void nbd_accept(QIONetListener *listener, QIOChannelSocket *cioc, nbd_update_server_watch(nbd_server); qio_channel_set_name(QIO_CHANNEL(cioc), "nbd-server"); - nbd_client_new(cioc, nbd_server->tlscreds, nbd_server->tlsauthz, - nbd_blockdev_client_closed); + /* TODO - expose handshake timeout as QMP option */ + nbd_client_new(cioc, NBD_DEFAULT_HANDSHAKE_MAX_SECS, + nbd_server->tlscreds, nbd_server->tlsauthz, + nbd_blockdev_client_closed, NULL); } static void nbd_update_server_watch(NBDServerData *s) diff --git a/include/block/nbd.h b/include/block/nbd.h index 4e7bd6342f..1d4d65922d 100644 --- a/include/block/nbd.h +++ b/include/block/nbd.h @@ -33,6 +33,12 @@ typedef struct NBDMetaContexts NBDMetaContexts; extern const BlockExportDriver blk_exp_nbd; +/* + * NBD_DEFAULT_HANDSHAKE_MAX_SECS: Number of seconds in which client must + * succeed at NBD_OPT_GO before being forcefully dropped as too slow. + */ +#define NBD_DEFAULT_HANDSHAKE_MAX_SECS 10 + /* Handshake phase structs - this struct is passed on the wire */ typedef struct NBDOption { @@ -403,9 +409,12 @@ AioContext *nbd_export_aio_context(NBDExport *exp); NBDExport *nbd_export_find(const char *name); void nbd_client_new(QIOChannelSocket *sioc, + uint32_t handshake_max_secs, QCryptoTLSCreds *tlscreds, const char *tlsauthz, - void (*close_fn)(NBDClient *, bool)); + void (*close_fn)(NBDClient *, bool), + void *owner); +void *nbd_client_owner(NBDClient *client); void nbd_client_get(NBDClient *client); void nbd_client_put(NBDClient *client); diff --git a/nbd/server.c b/nbd/server.c index 3d8ddfef06..91131883ee 100644 --- a/nbd/server.c +++ b/nbd/server.c @@ -124,12 +124,14 @@ struct NBDMetaContexts { struct NBDClient { int refcount; /* atomic */ void (*close_fn)(NBDClient *client, bool negotiated); + void *owner; QemuMutex lock; NBDExport *exp; QCryptoTLSCreds *tlscreds; char *tlsauthz; + uint32_t handshake_max_secs; QIOChannelSocket *sioc; /* The underlying data channel */ QIOChannel *ioc; /* The current I/O channel which may differ (eg TLS) */ @@ -3194,6 +3196,7 @@ static coroutine_fn void nbd_co_client_start(void *opaque) qemu_co_mutex_init(&client->send_lock); + /* TODO - utilize client->handshake_max_secs */ if (nbd_negotiate(client, &local_err)) { if (local_err) { error_report_err(local_err); @@ -3208,14 +3211,17 @@ static coroutine_fn void nbd_co_client_start(void *opaque) } /* - * Create a new client listener using the given channel @sioc. + * Create a new client listener using the given channel @sioc and @owner. * Begin servicing it in a coroutine. When the connection closes, call - * @close_fn with an indication of whether the client completed negotiation. + * @close_fn with an indication of whether the client completed negotiation + * within @handshake_max_secs seconds (0 for unbounded). */ void nbd_client_new(QIOChannelSocket *sioc, + uint32_t handshake_max_secs, QCryptoTLSCreds *tlscreds, const char *tlsauthz, - void (*close_fn)(NBDClient *, bool)) + void (*close_fn)(NBDClient *, bool), + void *owner) { NBDClient *client; Coroutine *co; @@ -3228,13 +3234,21 @@ void nbd_client_new(QIOChannelSocket *sioc, object_ref(OBJECT(client->tlscreds)); } client->tlsauthz = g_strdup(tlsauthz); + client->handshake_max_secs = handshake_max_secs; client->sioc = sioc; qio_channel_set_delay(QIO_CHANNEL(sioc), false); object_ref(OBJECT(client->sioc)); client->ioc = QIO_CHANNEL(sioc); object_ref(OBJECT(client->ioc)); client->close_fn = close_fn; + client->owner = owner; co = qemu_coroutine_create(nbd_co_client_start, client); qemu_coroutine_enter(co); } + +void * +nbd_client_owner(NBDClient *client) +{ + return client->owner; +} diff --git a/qemu-nbd.c b/qemu-nbd.c index 186e6468b1..5fa399c0b4 100644 --- a/qemu-nbd.c +++ b/qemu-nbd.c @@ -389,7 +389,9 @@ static void nbd_accept(QIONetListener *listener, QIOChannelSocket *cioc, nb_fds++; nbd_update_server_watch(); - nbd_client_new(cioc, tlscreds, tlsauthz, nbd_client_closed); + /* TODO - expose handshake timeout as command line option */ + nbd_client_new(cioc, NBD_DEFAULT_HANDSHAKE_MAX_SECS, + tlscreds, tlsauthz, nbd_client_closed, NULL); } static void nbd_update_server_watch(void)