From patchwork Mon Sep 9 14:16:27 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: =?utf-8?q?Daniel_P=2E_Berrang=C3=A9?= X-Patchwork-Id: 13797165 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 4C95FECE57A for ; Mon, 9 Sep 2024 14:18:03 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1snfCU-0007u2-Bw; Mon, 09 Sep 2024 10:17:06 -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 1snfCT-0007s2-KW for qemu-devel@nongnu.org; Mon, 09 Sep 2024 10:17:05 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1snfCR-0003Ix-Ps for qemu-devel@nongnu.org; Mon, 09 Sep 2024 10:17:05 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1725891423; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=fPO4I0oxWW77zveyLGOcTMiBWgRiSGpWO8LL8G9uTno=; b=iPrLjLFYMIo8Ra5zA7EvKfmzf//GDZPQ/lWCKr39Sw+l8tAdaF0R0QXLjehaAGfdavrlYn PzgrHLdkIoM/G7Z8Jltr4iqG0a0W35aShEJTCKOiwxH4Oq8iMncvPyR6SIZJH3uEJLpJFx S8HBTxj2vvP5cGZts0nW9qMvNS1P5Ww= Received: from mx-prod-mc-02.mail-002.prod.us-west-2.aws.redhat.com (ec2-54-186-198-63.us-west-2.compute.amazonaws.com [54.186.198.63]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-526-ilg3g7raMgmWJL1ADe6MUw-1; Mon, 09 Sep 2024 10:16:59 -0400 X-MC-Unique: ilg3g7raMgmWJL1ADe6MUw-1 Received: from mx-prod-int-04.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-04.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.40]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-02.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 7C4A01953965; Mon, 9 Sep 2024 14:16:57 +0000 (UTC) Received: from toolbox.redhat.com (unknown [10.42.28.212]) by mx-prod-int-04.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTP id 86A4C1955F45; Mon, 9 Sep 2024 14:16:52 +0000 (UTC) From: =?utf-8?q?Daniel_P=2E_Berrang=C3=A9?= To: qemu-devel@nongnu.org Cc: Hyman Huang , =?utf-8?q?Daniel_P=2E_Berrang=C3=A9?= , =?utf-8?q?Marc?= =?utf-8?q?-Andr=C3=A9_Lureau?= , Eric Blake , =?utf-8?q?Philippe_Mathieu-Daud=C3=A9?= , Hanna Reitz , qemu-block@nongnu.org, qemu-stable@nongnu.org, Laurent Vivier , Thomas Huth , Paolo Bonzini , Kevin Wolf , Markus Armbruster , Tiago Pasqualini Subject: [PULL 02/10] crypto: run qcrypto_pbkdf2_count_iters in a new thread Date: Mon, 9 Sep 2024 15:16:27 +0100 Message-ID: <20240909141635.1459701-3-berrange@redhat.com> In-Reply-To: <20240909141635.1459701-1-berrange@redhat.com> References: <20240909141635.1459701-1-berrange@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.0 on 10.30.177.40 Received-SPF: pass client-ip=170.10.133.124; envelope-from=berrange@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -21 X-Spam_score: -2.2 X-Spam_bar: -- X-Spam_report: (-2.2 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.141, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H4=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 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: Tiago Pasqualini CPU time accounting in the kernel has been demonstrated to have a sawtooth pattern[1][2]. This can cause the getrusage system call to not be as accurate as we are expecting, which can cause this calculation to stall. The kernel discussions shows that this inaccuracy happens when CPU time gets big enough, so this patch changes qcrypto_pbkdf2_count_iters to run in a fresh thread to avoid this inaccuracy. It also adds a sanity check to fail the process if CPU time is not accounted. [1] https://lore.kernel.org/lkml/159231011694.16989.16351419333851309713.tip-bot2@tip-bot2/ [2] https://lore.kernel.org/lkml/20221226031010.4079885-1-maxing.lan@bytedance.com/t/#m1c7f2fdc0ea742776a70fd1aa2a2e414c437f534 Resolves: #2398 Signed-off-by: Tiago Pasqualini Signed-off-by: Daniel P. Berrangé --- crypto/pbkdf.c | 53 +++++++++++++++++++++++++++++++++++++++++++------- 1 file changed, 46 insertions(+), 7 deletions(-) diff --git a/crypto/pbkdf.c b/crypto/pbkdf.c index 8d198c152c..d1c06ef3ed 100644 --- a/crypto/pbkdf.c +++ b/crypto/pbkdf.c @@ -19,6 +19,7 @@ */ #include "qemu/osdep.h" +#include "qemu/thread.h" #include "qapi/error.h" #include "crypto/pbkdf.h" #ifndef _WIN32 @@ -85,12 +86,28 @@ static int qcrypto_pbkdf2_get_thread_cpu(unsigned long long *val_ms, #endif } -uint64_t qcrypto_pbkdf2_count_iters(QCryptoHashAlgorithm hash, - const uint8_t *key, size_t nkey, - const uint8_t *salt, size_t nsalt, - size_t nout, - Error **errp) +typedef struct CountItersData { + QCryptoHashAlgorithm hash; + const uint8_t *key; + size_t nkey; + const uint8_t *salt; + size_t nsalt; + size_t nout; + uint64_t iterations; + Error **errp; +} CountItersData; + +static void *threaded_qcrypto_pbkdf2_count_iters(void *data) { + CountItersData *iters_data = (CountItersData *) data; + QCryptoHashAlgorithm hash = iters_data->hash; + const uint8_t *key = iters_data->key; + size_t nkey = iters_data->nkey; + const uint8_t *salt = iters_data->salt; + size_t nsalt = iters_data->nsalt; + size_t nout = iters_data->nout; + Error **errp = iters_data->errp; + uint64_t ret = -1; g_autofree uint8_t *out = g_new(uint8_t, nout); uint64_t iterations = (1 << 15); @@ -114,7 +131,10 @@ uint64_t qcrypto_pbkdf2_count_iters(QCryptoHashAlgorithm hash, delta_ms = end_ms - start_ms; - if (delta_ms > 500) { + if (delta_ms == 0) { /* sanity check */ + error_setg(errp, "Unable to get accurate CPU usage"); + goto cleanup; + } else if (delta_ms > 500) { break; } else if (delta_ms < 100) { iterations = iterations * 10; @@ -129,5 +149,24 @@ uint64_t qcrypto_pbkdf2_count_iters(QCryptoHashAlgorithm hash, cleanup: memset(out, 0, nout); - return ret; + iters_data->iterations = ret; + return NULL; +} + +uint64_t qcrypto_pbkdf2_count_iters(QCryptoHashAlgorithm hash, + const uint8_t *key, size_t nkey, + const uint8_t *salt, size_t nsalt, + size_t nout, + Error **errp) +{ + CountItersData data = { + hash, key, nkey, salt, nsalt, nout, 0, errp + }; + QemuThread thread; + + qemu_thread_create(&thread, "pbkdf2", threaded_qcrypto_pbkdf2_count_iters, + &data, QEMU_THREAD_JOINABLE); + qemu_thread_join(&thread); + + return data.iterations; }