From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by passt.top (Postfix) with ESMTP id E9DA25A026D for ; Wed, 23 Aug 2023 15:53:30 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1692798809; 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:in-reply-to:in-reply-to: references:references; bh=zpOPoRGnZrDTFL/0kNZg7uIlm75VosKODYBYKawHa6s=; b=PUOMwplX4kiquB7HHpmmIsaSROVltCMhgI/cQWq8dAwIJnHdM33usZ44PWUTOtxMmk1kbg 8GawX/YQthOX+B4shUlW8SLn48wH06tts2J1k+h329EAgW9OPUmCtezjWDeGSzpVXDmSmh Tz8a3j88hveRwElFCLBuaPLKUB8KTmg= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-599-6aIWS6PhPteCYnkXqJ9bpA-1; Wed, 23 Aug 2023 09:53:28 -0400 X-MC-Unique: 6aIWS6PhPteCYnkXqJ9bpA-1 Received: from smtp.corp.redhat.com (int-mx09.intmail.prod.int.rdu2.redhat.com [10.11.54.9]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 4FA2B8D40A4; Wed, 23 Aug 2023 13:53:28 +0000 (UTC) Received: from localhost (unknown [10.42.28.187]) by smtp.corp.redhat.com (Postfix) with ESMTP id 1CFED492C14; Wed, 23 Aug 2023 13:53:28 +0000 (UTC) Date: Wed, 23 Aug 2023 14:53:27 +0100 From: "Richard W.M. Jones" To: Stefano Brivio Subject: Re: [PATCH] fedora: Replace pasta hard links by copies, mangle Build-IDs Message-ID: <20230823135327.GP7636@redhat.com> References: <20230823134844.2188790-1-sbrivio@redhat.com> MIME-Version: 1.0 In-Reply-To: <20230823134844.2188790-1-sbrivio@redhat.com> User-Agent: Mutt/1.5.21 (2010-09-15) X-Scanned-By: MIMEDefang 3.1 on 10.11.54.9 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Message-ID-Hash: C3HOJ2PGKBNGZSPXIET4KM57V6QGBNCX X-Message-ID-Hash: C3HOJ2PGKBNGZSPXIET4KM57V6QGBNCX X-MailFrom: rjones@redhat.com X-Mailman-Rule-Misses: dmarc-mitigation; no-senders; approved; emergency; loop; banned-address; member-moderation; nonmember-moderation; administrivia; implicit-dest; max-recipients; max-size; news-moderation; no-subject; digests; suspicious-header CC: passt-dev@passt.top, devel@lists.fedoraproject.org X-Mailman-Version: 3.3.8 Precedence: list Reply-To: devel@lists.fedoraproject.org List-Id: Development discussion and patches for passt Archived-At: Archived-At: List-Archive: List-Archive: List-Help: List-Owner: List-Post: List-Subscribe: List-Unsubscribe: On Wed, Aug 23, 2023 at 03:48:44PM +0200, Stefano Brivio wrote: > The hard link trick didn't actually fix the issue with SELinux file > contexts properly: as opposed to symbolic links, SELinux now > correctly associates types to the labels that are set -- except that > those labels are now shared, so we can end up (depending on how > rpm(8) extracts the archives) with /usr/bin/passt having a > pasta_exec_t context. > > This got rather confusing as running restorecon(8) seemed to fix up > labels -- but that's simply toggling between passt_exec_t and > pasta_exec_t for both links, because each invocation will just "fix" > the file with the mismatching context. > > Replace the hard links with copies. AppArmor's attachment, instead, > works with hard links, and if there's no LSM, we can keep symbolic > links, so keep symbolic links in the Makefile. > > With copies, rpmbuild(8) will warn about duplicate Build-IDs in the > same package. Mangle them in pasta binaries by summing one to the > last byte, modulo one byte, using xxd (provided by vim-common) and > disable the automatic rehashing by find-debuginfo(1) -- we already > have per-release Build-IDs thanks to $VERSION passed on 'make'. Right, this ^ was going to be my comment. RPM doesn't like having two identical copies of a file. Hacking the binary to "fix" the problem doesn't sound like a solution. I'm CC-ing Fedora-devel-list to find out we can properly fix this issue. Rich. > Signed-off-by: Stefano Brivio > --- > contrib/fedora/passt.spec | 27 ++++++++++++++++++++++----- > 1 file changed, 22 insertions(+), 5 deletions(-) > > diff --git a/contrib/fedora/passt.spec b/contrib/fedora/passt.spec > index d0c6895..51bf5a8 100644 > --- a/contrib/fedora/passt.spec > +++ b/contrib/fedora/passt.spec > @@ -9,6 +9,10 @@ > > %global git_hash {{{ git_head }}} > %global selinuxtype targeted > +# Different Build-IDs for passt and pasta: don't let find-debuginfo touch them > +%undefine _unique_build_ids > +%global _no_recompute_build_ids 1 > + > > Name: passt > Version: {{{ git_version }}} > @@ -19,7 +23,7 @@ Group: System Environment/Daemons > URL: https://passt.top/ > Source: https://passt.top/passt/snapshot/passt-%{git_hash}.tar.xz > > -BuildRequires: gcc, make, checkpolicy, selinux-policy-devel > +BuildRequires: gcc, make, checkpolicy, selinux-policy-devel, binutils, vim-common > Requires: (%{name}-selinux = %{version}-%{release} if selinux-policy-%{selinuxtype}) > > %description > @@ -56,15 +60,28 @@ This package adds SELinux enforcement to passt(1) and pasta(1). > %install > > %make_install DESTDIR=%{buildroot} prefix=%{_prefix} bindir=%{_bindir} mandir=%{_mandir} docdir=%{_docdir}/%{name} > -# The Makefile creates symbolic links for pasta, but we need hard links for > +# The Makefile creates symbolic links for pasta, but we need actual copies for > # SELinux file contexts to work as intended. Same with pasta.avx2 if present. > -ln -f %{buildroot}%{_bindir}/passt %{buildroot}%{_bindir}/pasta > +# > +# To avoid duplicate Build-IDs in the same package, we increase the last byte of > +# the value for pasta binaries by one (modulo one byte). Note that we already > +# have differentiated Build-IDs per release, courtesy of $VERSION, so we don't > +# need find-debuginfo(1) to recalculate them. > +rm %{buildroot}%{_bindir}/pasta > +objcopy --dump-section .note.gnu.build-id=%{buildroot}/build_id %{buildroot}%{_bindir}/passt > +printf '\x'$(printf %02x $(( ( 0x$(xxd -ps -s 35 %{buildroot}/build_id) + 1 ) % 0xff )) ) | dd of=%{buildroot}/build_id seek=35 bs=1 count=1 conv=notrunc > +objcopy --update-section .note.gnu.build-id=%{buildroot}/build_id %{buildroot}%{_bindir}/passt %{buildroot}%{_bindir}/pasta > +rm %{buildroot}/build_id > + > %ifarch x86_64 > -ln -f %{buildroot}%{_bindir}/passt.avx2 %{buildroot}%{_bindir}/pasta.avx2 > +rm %{buildroot}%{_bindir}/pasta.avx2 > +objcopy --dump-section .note.gnu.build-id=%{buildroot}/build_id %{buildroot}%{_bindir}/passt.avx2 > +printf '\x'$(printf %02x $(( ( 0x$(xxd -ps -s 35 %{buildroot}/build_id) + 1 ) % 0xff )) ) | dd of=%{buildroot}/build_id seek=35 bs=1 count=1 conv=notrunc > +objcopy --update-section .note.gnu.build-id=%{buildroot}/build_id %{buildroot}%{_bindir}/passt.avx2 %{buildroot}%{_bindir}/pasta.avx2 > +rm %{buildroot}/build_id > > ln -sr %{buildroot}%{_mandir}/man1/passt.1 %{buildroot}%{_mandir}/man1/passt.avx2.1 > ln -sr %{buildroot}%{_mandir}/man1/pasta.1 %{buildroot}%{_mandir}/man1/pasta.avx2.1 > -install -p -m 755 %{buildroot}%{_bindir}/passt.avx2 %{buildroot}%{_bindir}/pasta.avx2 > %endif > > pushd contrib/selinux > -- > 2.39.2 -- Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones Read my programming and virtualization blog: http://rwmj.wordpress.com virt-p2v converts physical machines to virtual machines. Boot with a live CD or over the network (PXE) and turn machines into KVM guests. http://libguestfs.org/virt-v2v