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 lists1p.gnu.org (lists1p.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 189FACD4F49 for ; Mon, 18 May 2026 16:04:35 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists1p.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1wP0RP-0002yd-2N; Mon, 18 May 2026 12:03:39 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists1p.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1wP0Qr-0002gZ-9O for qemu-trivial@nongnu.org; Mon, 18 May 2026 12:03:10 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.129.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1wP0Qp-000722-9j for qemu-trivial@nongnu.org; Mon, 18 May 2026 12:03:05 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1779120182; 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; bh=zjBZEXc8Xf4ULSZsuieQsF8nx4sSrSvG7ZfuVe/yj98=; b=JDSUSbfSHNxxSmEyd8GyK/MHxTJi+etBcLTh+zsxuIdaq26GOBP37Pmjq/Z94eZ3cWuvyr GyhidgiUX5jUglzSAKpY9LXkWLWZlFLS1FyBmKn4bo4f3N4Sf/705r0WMFs2edMNrLRplO swkhEmypHTy0GECNLOEgpIynTSeT8TE= Received: from mx-prod-mc-06.mail-002.prod.us-west-2.aws.redhat.com (ec2-35-165-154-97.us-west-2.compute.amazonaws.com [35.165.154.97]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-659-LruNDJPLMqe_aJ15AInN-A-1; Mon, 18 May 2026 12:02:59 -0400 X-MC-Unique: LruNDJPLMqe_aJ15AInN-A-1 X-Mimecast-MFC-AGG-ID: LruNDJPLMqe_aJ15AInN-A_1779120178 Received: from mx-prod-int-01.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-01.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.4]) (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-06.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 33A71180060D; Mon, 18 May 2026 16:02:58 +0000 (UTC) Received: from thuth-p1g4.redhat.corp (headnet01.pony-001.prod.iad2.dc.redhat.com [10.2.32.101]) by mx-prod-int-01.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTP id 1F60130001A2; Mon, 18 May 2026 16:02:56 +0000 (UTC) From: Thomas Huth To: qemu-devel@nongnu.org Cc: qemu-trivial@nongnu.org Subject: [PATCH] system/rtc: Fix a possible year-2038 integer overflow problem Date: Mon, 18 May 2026 18:02:55 +0200 Message-ID: <20260518160255.1844308-1-thuth@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.4.1 on 10.30.177.4 X-Mimecast-MFC-PROC-ID: OpH-uohJK23_M8_qShleH3hhE6v_6W6DvI-XWtZ6IxI_1779120178 X-Mimecast-Originator: redhat.com Content-Transfer-Encoding: 8bit content-type: text/plain; charset="US-ASCII"; x-default=true Received-SPF: pass client-ip=170.10.129.124; envelope-from=thuth@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -24 X-Spam_score: -2.5 X-Spam_bar: -- X-Spam_report: (-2.5 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.445, 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_PASS=-0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-trivial@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-trivial-bounces+qemu-trivial=archiver.kernel.org@nongnu.org Sender: qemu-trivial-bounces+qemu-trivial=archiver.kernel.org@nongnu.org From: Thomas Huth rtc_realtime_clock_offset is initialized with: rtc_realtime_clock_offset = qemu_clock_get_ms(QEMU_CLOCK_REALTIME) / 1000; And QEMU_CLOCK_REALTIME might be based on gettimeofday() in certain cases (see get_clock_realtime() in include/qemu/timer.h). So this counter will exceed 32 bits in the year 2038, thus we should not store this value in a normal integer variable. Change it to an int64_t to fix the problem. And while we're at it, also adjust the nearby rtc_host_datetime_offset variable to be on the safe side in the related code. Signed-off-by: Thomas Huth --- system/rtc.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/system/rtc.c b/system/rtc.c index f13dd392a76..83b28088054 100644 --- a/system/rtc.c +++ b/system/rtc.c @@ -41,8 +41,8 @@ static enum { RTC_BASE_DATETIME, } rtc_base_type = RTC_BASE_UTC; static time_t rtc_ref_start_datetime; -static int rtc_realtime_clock_offset; /* used only with QEMU_CLOCK_REALTIME */ -static int rtc_host_datetime_offset = -1; /* valid & used only with +static int64_t rtc_realtime_clock_offset; /* used only with QEMU_CLOCK_REALTIME */ +static int64_t rtc_host_datetime_offset = -1; /* valid & used only with RTC_BASE_DATETIME */ QEMUClockType rtc_clock; /***********************************************************/ -- 2.54.0