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 9EC1DCC6B33 for ; Thu, 15 Oct 2026 10:11:18 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists1p.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1xHIQN-0006G2-E7; Thu, 15 Oct 2026 06:10:59 -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 1xHIQI-0006F5-BM for qemu-devel@nongnu.org; Thu, 15 Oct 2026 06:10:54 -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 1xHIQG-0001ql-Gt for qemu-devel@nongnu.org; Thu, 15 Oct 2026 06:10:54 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1792059051; h=from:from:reply-to: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=wlsRRlDrzQzhoLAg4D+iDOmjNnK4G7fJK+BkK1rB8Kc=; b=gPQw8i2U1FVlcgKOij6wzf03l/OuvvgrnwFQXLpAxJmptp+NRL/D6LKdBvhIrDZi2+YQGK nzx1xNgMW+0tQ/UXvFZKvh/rXUHW4ZZMtv/bAChZuMAC5IqxnAbFeP+ltu7tZ4tjethjkY ne1D32PblpwB3gWQDf3PvPZ64AZJAkU= Received: from mx-prod-mc-08.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-595-3Xjt3qfXMc-5kjZi6tfz2Q-1; Thu, 15 Oct 2026 10:10:41 +0000 X-MC-Unique: 3Xjt3qfXMc-5kjZi6tfz2Q-1 X-Mimecast-MFC-AGG-ID: 3Xjt3qfXMc-5kjZi6tfz2Q_1792059040 Received: from mx-prod-int-05.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-05.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.17]) (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-08.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id C75E9180066C; Thu, 15 Oct 2026 10:10:39 +0000 (UTC) Received: from redhat.com (headnet04.pony-001.prod.iad2.dc.redhat.com [10.2.32.116]) by mx-prod-int-05.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 5D19A1956087; Thu, 15 Oct 2026 10:10:34 +0000 (UTC) Date: Thu, 15 Oct 2026 11:10:31 +0100 From: Daniel =?utf-8?B?UC4gQmVycmFuZ8Op?= To: Filip Hejsek Cc: qemu-devel@nongnu.org, "Michael S. Tsirkin" , Paolo Bonzini , =?utf-8?Q?Marc-Andr=C3=A9?= Lureau , Michael Tokarev , Laurent Vivier , Eric Blake , Vladimir Sementsov-Ogievskiy , qemu-block@nongnu.org, "Maciej S. Szmigiero" , Peter Xu , Fabiano Rosas , Mark Kanda , Ben Chaney , Igor Mammedov , Ani Sinha Subject: Re: [PATCH v3] treewide: use qemu_dup() instead of dup() Message-ID: References: <20261015-use-qemu-dup-v3-1-ca02b5927725@gmail.com> <85c97944e59abe645eb95602b7193cba15e3a17a.camel@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <85c97944e59abe645eb95602b7193cba15e3a17a.camel@gmail.com> User-Agent: Mutt/2.4.2 (2026-08-30) X-Scanned-By: MIMEDefang 3.0 on 10.30.177.17 Received-SPF: pass client-ip=170.10.129.124; envelope-from=berrange@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -22 X-Spam_score: -2.3 X-Spam_bar: -- X-Spam_report: (-2.3 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.24, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, SPF_HELO_PASS=-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: qemu development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Reply-To: Daniel =?utf-8?B?UC4gQmVycmFuZ8Op?= Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org On Thu, Oct 15, 2026 at 12:09:22PM +0200, Filip Hejsek wrote: > On Thu, 2026-10-15 at 09:04 +0100, Daniel P. Berrangé wrote: > > On Thu, Oct 15, 2026 at 03:34:43AM +0200, Filip Hejsek wrote: > > > Use qemu_dup() to ensure the cloexec flag is set on dup'd fds. > > > > > > The only direct users of dup() are now guest syscalls in the user > > > emulators and the implementation of qemu_dup() itself. > > > > > > Signed-off-by: Filip Hejsek > > > --- > > > For each call I replaced, I checked how the resulting fd is used > > > afterwards. In summary: > > > > > > hw/virtio/virtio.c: > > > the fd is passed to memory_region_init_ram_from_fd, used for mmaping > > > > > > io/channel-file.c: > > > the fd is passed to qio_channel_file_new_fd, used for reading/writing > > > > > > migration/cpr-exec.c: > > > the cloexec flag is cleared > > > > > > qemu-nbd.c: > > > the fd is stored into old_stderr, then dup2'd back to STDERR_FILENO > > > > > > system/vl.c: > > > no change in behavior, the code was already setting the cloexec flag > > > > > > ui/dmabuf.c: > > > the function is called by qemu_spice_gl_update, which passes the fds > > > to SPICE server > > > > > > tests/qtest/bios-tables-test.c: > > > temp dup of stdout, dup2'd back to STDOUT_FILENO > > > > > > tests/unit/test-util-sockets.c: > > > one fd is dup'd again and returned from mock monitor_get_fd; another > > > is converted to string and given as address to socket_connect > > > > > > tests/unit/test-vmstate.c: > > > passed to qio_channel_file_new_fd to create a channel > > > > > > Changes in v3: > > > - Also replace the use in migration/cpr-exec.c and the tests > > > - Link to v2: https://lore.kernel.org/qemu-devel/20261013-use-qemu-dup-v2-1-12ecd94263b7@gmail.com > > > > > > Changes in v2: > > > - Replace the use in qemu-nbd.c too > > > - Changed commit message > > > - Link to v1: https://lore.kernel.org/qemu-devel/20261012-use-qemu-dup-v1-1-03d94852a6c8@gmail.com > > > --- > > > hw/virtio/virtio.c | 2 +- > > > io/channel-file.c | 2 +- > > > migration/cpr-exec.c | 2 +- > > > qemu-nbd.c | 2 +- > > > system/vl.c | 9 +-------- > > > tests/qtest/bios-tables-test.c | 2 +- > > > tests/unit/test-util-sockets.c | 6 +++--- > > > tests/unit/test-vmstate.c | 2 +- > > > ui/dmabuf.c | 2 +- > > > 9 files changed, 11 insertions(+), 18 deletions(-) > > > > > > > diff --git a/migration/cpr-exec.c b/migration/cpr-exec.c > > > index daa50916d2..2f38db30bb 100644 > > > --- a/migration/cpr-exec.c > > > +++ b/migration/cpr-exec.c > > > @@ -44,7 +44,7 @@ bool cpr_exec_persist_state(QEMUFile *f, Error **errp) > > > { > > > QIOChannelFile *fioc = QIO_CHANNEL_FILE(qemu_file_get_ioc(f)); > > > /* coverity[leaked_storage] - mfd intentionally kept open across exec() */ > > > - int mfd = dup(fioc->fd); > > > + int mfd = qemu_dup(fioc->fd); > > > char val[16]; > > > > This change needed to be: > > > > int mfd = qemu_dup(fioc->fd); > > qemu_clear_cloexec(fioc->fd); > > > > There was a call to qemu_clear_cloexec(mfd) already, even before the > change, just outside the visible hunk: Oppps, yes, thanks for pointing that out. In that case, Reviewed-by: Daniel P. Berrangé With regards, Daniel -- |: https://berrange.com ~~ https://hachyderm.io/@berrange :| |: https://libvirt.org ~~ https://entangle-photo.org :| |: https://pixelfed.art/berrange ~~ https://fstop138.berrange.com :|