From nobody Sun Feb 8 21:47:32 2026 Delivered-To: importer@patchew.org Authentication-Results: mx.zohomail.com; dkim=fail; spf=pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; dmarc=fail(p=none dis=none) header.from=redhat.com ARC-Seal: i=1; a=rsa-sha256; t=1619696356; cv=none; d=zohomail.com; s=zohoarc; b=Twzj62aJaP4QADIJ01h/JXDceTKGSmc6IUSN9s6RKt6FA1KF2Yk6h8l2OG1NInQX2iNhZlKhJJ6aNQ8v4abieVymkv2zJMM8Dt8CO6JO82MqsyRyYyk0f8E4AmIqpEtBae0+Aok3E3Xcqjat4kmfgajSjuVdCy0toTDxBhjiiJE= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=zohomail.com; s=zohoarc; t=1619696356; h=Content-Type:Content-Transfer-Encoding:Cc:Date:From:In-Reply-To:List-Subscribe:List-Post:List-Id:List-Archive:List-Help:List-Unsubscribe:MIME-Version:Message-ID:References:Sender:Subject:To; bh=nq+3IeRzoepyEJ0CosTis2dz02HyPiq+/3zoaugBJJ8=; b=eD8EXD9/s042goLJi/ZGtnjx/MigaTvy8zHPMC5Nr2bhetVCKXx1mMpu8DLSAxCRkyMKU6O/NTA6JQLARtPHxYkq1+hPoc6os4nF23O1w/0BnKJOEdGpdisVRgnSGthyEgnQb5VnhQb6wBGB8NAuMrHOkmRmP1xEFUnnlOyw1FM= ARC-Authentication-Results: i=1; mx.zohomail.com; dkim=fail; spf=pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; dmarc=fail header.from= (p=none dis=none) header.from= Return-Path: Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) by mx.zohomail.com with SMTPS id 1619696356177398.37734504051593; Thu, 29 Apr 2021 04:39:16 -0700 (PDT) Received: from localhost ([::1]:41432 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1lc50l-0007U5-4L for importer@patchew.org; Thu, 29 Apr 2021 07:39:15 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:58636) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lc4q9-0000Ai-RV for qemu-devel@nongnu.org; Thu, 29 Apr 2021 07:28:17 -0400 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:28627) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lc4q8-0003km-6N for qemu-devel@nongnu.org; Thu, 29 Apr 2021 07:28:17 -0400 Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-33-kbDAFACiOna2dFJuuTsvxw-1; Thu, 29 Apr 2021 07:28:13 -0400 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 7C993803622; Thu, 29 Apr 2021 11:28:12 +0000 (UTC) Received: from t480s.redhat.com (ovpn-114-50.ams2.redhat.com [10.36.114.50]) by smtp.corp.redhat.com (Postfix) with ESMTP id 0730E17177; Thu, 29 Apr 2021 11:28:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1619695695; 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=nq+3IeRzoepyEJ0CosTis2dz02HyPiq+/3zoaugBJJ8=; b=Fx+lnElSeUJnlwtYx2L57uzIoHqr6reH2viNszTJHsQvz2FPvGPT7sb7Tr4shIIR41F8T5 rDXgB+6TCxTwDAzSho6ydF1YfCfyK+5YN4Fv2ESMcvDIkCe9y3azxO+HUZscOEQk8zPp7a laFj5yU5k3srzVHH3r9ciYfinZcUZ/4= X-MC-Unique: kbDAFACiOna2dFJuuTsvxw-1 From: David Hildenbrand To: qemu-devel@nongnu.org Subject: [PATCH v5 05/10] exec: Relax range check in ram_block_discard_range() Date: Thu, 29 Apr 2021 13:27:03 +0200 Message-Id: <20210429112708.12291-6-david@redhat.com> In-Reply-To: <20210429112708.12291-1-david@redhat.com> References: <20210429112708.12291-1-david@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=david@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Transfer-Encoding: quoted-printable Received-SPF: pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) client-ip=209.51.188.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Received-SPF: pass client-ip=216.205.24.124; envelope-from=david@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -29 X-Spam_score: -3.0 X-Spam_bar: --- X-Spam_report: (-3.0 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.22, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_LOW=-0.7, 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: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Eduardo Habkost , "Michael S. Tsirkin" , David Hildenbrand , Richard Henderson , "Dr. David Alan Gilbert" , Peter Xu , Juan Quintela , Alex Williamson , Paolo Bonzini Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" X-ZohoMail-DKIM: fail (Header signature does not verify) Content-Type: text/plain; charset="utf-8" We want to make use of ram_block_discard_range() in the RAM block resize callback when growing a RAM block, *before* used_length is changed. Let's relax the check. As RAM blocks always mmap the whole max_length area, we cannot corrupt unrelated data. Reviewed-by: Peter Xu Signed-off-by: David Hildenbrand --- softmmu/physmem.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/softmmu/physmem.c b/softmmu/physmem.c index 4834003d47..4e587de150 100644 --- a/softmmu/physmem.c +++ b/softmmu/physmem.c @@ -3503,7 +3503,7 @@ int ram_block_discard_range(RAMBlock *rb, uint64_t st= art, size_t length) goto err; } =20 - if ((start + length) <=3D rb->used_length) { + if ((start + length) <=3D rb->max_length) { bool need_madvise, need_fallocate; if (!QEMU_IS_ALIGNED(length, rb->page_size)) { error_report("ram_block_discard_range: Unaligned length: %zx", @@ -3570,7 +3570,7 @@ int ram_block_discard_range(RAMBlock *rb, uint64_t st= art, size_t length) } else { error_report("ram_block_discard_range: Overrun block '%s' (%" PRIu= 64 "/%zx/" RAM_ADDR_FMT")", - rb->idstr, start, length, rb->used_length); + rb->idstr, start, length, rb->max_length); } =20 err: --=20 2.30.2