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 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 7EE87C48260 for ; Tue, 13 Feb 2024 13:59:23 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1rZtJK-0004Sk-56; Tue, 13 Feb 2024 08:58:58 -0500 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 1rZtJJ-0004Sa-Ah for qemu-devel@nongnu.org; Tue, 13 Feb 2024 08:58:57 -0500 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 1rZtJH-0000TW-KN for qemu-devel@nongnu.org; Tue, 13 Feb 2024 08:58:57 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1707832734; 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=WqEYDGP3kp2uAbpHCcqgUfmOCHyDZTMiGBTaGMtIzf0=; b=WkxgHWJh7IwRVIsFMUmMIMN1M785lqSR8diRwpckvZWmxjx2C/ydJ3m8q9S0bOC7SKE4sj qO+1BEUgrB4OS2bQjgHrdwyezHA+93QimVxQPkpWkAc2Dz0AotA6yrC/WsiBfHdG79UmYe kC8bfuLyHw10WKkqcR0X79QMCIbAuw4= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-138-vXWfjEeLOjKVURyBC5pdpg-1; Tue, 13 Feb 2024 08:58:53 -0500 X-MC-Unique: vXWfjEeLOjKVURyBC5pdpg-1 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.rdu2.redhat.com [10.11.54.2]) (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 mimecast-mx02.redhat.com (Postfix) with ESMTPS id D527184AC63; Tue, 13 Feb 2024 13:58:52 +0000 (UTC) Received: from blackfin.pond.sub.org (unknown [10.39.192.55]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 9691D40C9444; Tue, 13 Feb 2024 13:58:52 +0000 (UTC) Received: by blackfin.pond.sub.org (Postfix, from userid 1000) id 806F321E6767; Tue, 13 Feb 2024 14:58:47 +0100 (CET) From: Markus Armbruster To: qemu-devel@nongnu.org Cc: marcandre.lureau@redhat.com, pbonzini@redhat.com, devel@lists.libvirt.org, eblake@redhat.com Subject: Re: [PATCH 1/4] chardev/parallel: Don't close stdin on inappropriate device In-Reply-To: <20240203080228.2766159-2-armbru@redhat.com> (Markus Armbruster's message of "Sat, 3 Feb 2024 09:02:25 +0100") References: <20240203080228.2766159-1-armbru@redhat.com> <20240203080228.2766159-2-armbru@redhat.com> Date: Tue, 13 Feb 2024 14:58:47 +0100 Message-ID: <87mss479ew.fsf@pond.sub.org> User-Agent: Gnus/5.13 (Gnus v5.13) MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable X-Scanned-By: MIMEDefang 3.4.1 on 10.11.54.2 Received-SPF: pass client-ip=170.10.133.124; envelope-from=armbru@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -25 X-Spam_score: -2.6 X-Spam_bar: -- X-Spam_report: (-2.6 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.504, 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, 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 Markus Armbruster writes: > The __linux__ version of qemu_chr_open_pp_fd() tries to claim the > parport device with a PPCLAIM ioctl(). On success, it stores the file > descriptor in the chardev object, and returns success. On failure, it > closes the file descriptor, and returns failure. > > chardev_new() then passes the Chardev to object_unref(). This duly > calls char_parallel_finalize(), which closes the file descriptor > stored in the chardev object. Since qemu_chr_open_pp_fd() didn't > store it, it's still zero, so this closes standard input. Ooopsie. > > To demonstate, add a unit test. With the bug above unfixed, running > this test closes standard input. char_hotswap_test() happens to run > next. It opens a socket, duly gets file descriptor 0, and since it > tests for success with > 0 instead of >=3D 0, it fails. > > The test needs to be conditional exactly like the chardev it tests. > Since the condition is rather complicated, steal the solution from the > serial chardev: define HAVE_CHARDEV_PARALLEL in qemu/osdep.h. This > also permits simplifying chardev/meson.build a bit. > > The bug fix is easy enough: store the file descriptor, and leave > closing it to char_parallel_finalize(). > > Signed-off-by: Markus Armbruster [...] > diff --git a/chardev/char-parallel.c b/chardev/char-parallel.c > index a5164f975a..78697d7522 100644 > --- a/chardev/char-parallel.c > +++ b/chardev/char-parallel.c > @@ -164,13 +164,13 @@ static void qemu_chr_open_pp_fd(Chardev *chr, > { > ParallelChardev *drv =3D PARALLEL_CHARDEV(chr); >=20=20 > + drv->fd =3D fd; > + > if (ioctl(fd, PPCLAIM) < 0) { > error_setg_errno(errp, errno, "not a parallel port"); > - close(fd); > return; > } >=20=20 > - drv->fd =3D fd; > drv->mode =3D IEEE1284_MODE_COMPAT; > } > #endif /* __linux__ */ > @@ -238,6 +238,7 @@ static void qemu_chr_open_pp_fd(Chardev *chr, > } > #endif >=20=20 > +#ifdef HAVE_CHARDEV_PARALLEL > static void qmp_chardev_open_parallel(Chardev *chr, > ChardevBackend *backend, > bool *be_opened, > @@ -306,3 +307,5 @@ static void register_types(void) > } >=20=20 > type_init(register_types); > + > +#endif /* HAVE_CHARDEV_PARALLEL */ > diff --git a/tests/unit/test-char.c b/tests/unit/test-char.c > index 649fdf64e1..76946e6f90 100644 > --- a/tests/unit/test-char.c > +++ b/tests/unit/test-char.c > @@ -1203,6 +1203,24 @@ static void char_serial_test(void) > } > #endif >=20=20 > +#if defined(HAVE_CHARDEV_PARALLEL) && !defined(WIN32) > +static void char_parallel_test(void) > +{ > + QemuOpts *opts; > + Chardev *chr; > + > + opts =3D qemu_opts_create(qemu_find_opts("chardev"), "parallel-id", > + 1, &error_abort); > + qemu_opt_set(opts, "backend", "parallel", &error_abort); > + qemu_opt_set(opts, "path", "/dev/null", &error_abort); > + > + chr =3D qemu_chr_new_from_opts(opts, NULL, NULL); > + g_assert_null(chr); This is wrong. On a Linux host, qemu_chr_new_from_opts() fails, because qemu_chr_open_pp_fd()'s attempt to PPCLAIM fails. On a BSD host, it succeeds. Proposed fixup appended. Marc-Andr=C3=A9, is respinning the PR with the fixup okay, or would you prefer a v2? > + > + qemu_opts_del(opts); > +} > +#endif > + > #ifndef _WIN32 > static void char_file_fifo_test(void) > { > @@ -1544,6 +1562,9 @@ int main(int argc, char **argv) > g_test_add_func("/char/udp", char_udp_test); > #if defined(HAVE_CHARDEV_SERIAL) && !defined(WIN32) > g_test_add_func("/char/serial", char_serial_test); > +#endif > +#if defined(HAVE_CHARDEV_PARALLEL) && !defined(WIN32) > + g_test_add_func("/char/parallel", char_parallel_test); > #endif > g_test_add_func("/char/hotswap", char_hotswap_test); > g_test_add_func("/char/websocket", char_websock_test); [...] diff --git a/tests/unit/test-char.c b/tests/unit/test-char.c index e3b783c06b..f273ce5226 100644 --- a/tests/unit/test-char.c +++ b/tests/unit/test-char.c @@ -1215,7 +1215,13 @@ static void char_parallel_test(void) qemu_opt_set(opts, "path", "/dev/null", &error_abort); =20 chr =3D qemu_chr_new_from_opts(opts, NULL, NULL); +#ifdef __linux__ + /* fails to PPCLAIM, see qemu_chr_open_pp_fd() */ g_assert_null(chr); +#else + g_assert_nonnull(chr); + object_unparent(OBJECT(chr)); +#endif =20 qemu_opts_del(opts); }