From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from firstgate.proxmox.com (firstgate.proxmox.com [212.224.123.68]) by lore.proxmox.com (Postfix) with ESMTPS id 37C271FF13E for ; Fri, 06 Mar 2026 10:31:36 +0100 (CET) Received: from firstgate.proxmox.com (localhost [127.0.0.1]) by firstgate.proxmox.com (Proxmox) with ESMTP id 9B01B1CE3B; Fri, 6 Mar 2026 10:32:41 +0100 (CET) Date: Fri, 6 Mar 2026 10:32:07 +0100 From: Wolfgang Bumiller To: Filip Schauer Subject: Re: [PATCH container 5/8] namespaces: refactor run_in_userns Message-ID: References: <20260223130706.90972-1-f.schauer@proxmox.com> <20260223130706.90972-6-f.schauer@proxmox.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20260223130706.90972-6-f.schauer@proxmox.com> X-Bm-Milter-Handled: 55990f41-d878-4baa-be0a-ee34c49e34d2 X-Bm-Transport-Timestamp: 1772789499579 X-SPAM-LEVEL: Spam detection results: 0 AWL -0.985 Adjusted score from AWL reputation of From: address BAYES_00 -1.9 Bayes spam probability is 0 to 1% DMARC_MISSING 0.1 Missing DMARC policy KAM_DMARC_STATUS 0.01 Test Rule for DKIM or SPF Failure with Strict Alignment RCVD_IN_MSPIKE_H2 0.001 Average reputation (+2) RCVD_IN_VALIDITY_CERTIFIED_BLOCKED 0.617 ADMINISTRATOR NOTICE: The query to Validity was blocked. See https://knowledge.validity.com/hc/en-us/articles/20961730681243 for more information. RCVD_IN_VALIDITY_RPBL_BLOCKED 0.892 ADMINISTRATOR NOTICE: The query to Validity was blocked. See https://knowledge.validity.com/hc/en-us/articles/20961730681243 for more information. RCVD_IN_VALIDITY_SAFE_BLOCKED 0.622 ADMINISTRATOR NOTICE: The query to Validity was blocked. See https://knowledge.validity.com/hc/en-us/articles/20961730681243 for more information. SPF_HELO_NONE 0.001 SPF: HELO does not publish an SPF Record SPF_PASS -0.001 SPF: sender matches SPF record Message-ID-Hash: BSNZ4MPC25VZGRRRKKEPCFWDYJDNGGF6 X-Message-ID-Hash: BSNZ4MPC25VZGRRRKKEPCFWDYJDNGGF6 X-MailFrom: w.bumiller@proxmox.com X-Mailman-Rule-Misses: dmarc-mitigation; no-senders; approved; loop; banned-address; emergency; member-moderation; nonmember-moderation; administrivia; implicit-dest; max-recipients; max-size; news-moderation; no-subject; digests; suspicious-header CC: pve-devel@lists.proxmox.com X-Mailman-Version: 3.3.10 Precedence: list List-Id: Proxmox VE development discussion List-Help: List-Owner: List-Post: List-Subscribe: List-Unsubscribe: On Mon, Feb 23, 2026 at 02:04:51PM +0100, Filip Schauer wrote: > Signed-off-by: Filip Schauer > --- > src/PVE/LXC/Namespaces.pm | 27 +++++++++++++++++++-------- > 1 file changed, 19 insertions(+), 8 deletions(-) > > diff --git a/src/PVE/LXC/Namespaces.pm b/src/PVE/LXC/Namespaces.pm > index 3b86262..477d0ac 100644 > --- a/src/PVE/LXC/Namespaces.pm > +++ b/src/PVE/LXC/Namespaces.pm > @@ -25,6 +25,19 @@ my sub set_id_map($$) { > PVE::Tools::run_command(['newuidmap', $pid, @uid_args]) if scalar(@uid_args); > } > > +my sub sync_send { > + my ($fh, $msg) = @_; > + > + syswrite($fh, $msg) == length($msg) or die "sync write failed: $!\n"; Given what we use them for and that they're private to this module, we may as well include the $msg in the error. > +} > + > +my sub sync_recv { > + my ($fh, $expect) = @_; > + > + my $received = <$fh>; > + die "sync read failed\n" if $received ne $expect; Here, too. > +} > + > sub run_in_userns($;$) { > my ($code, $id_map) = @_; > socketpair(my $sp, my $sc, AF_UNIX, SOCK_STREAM, PF_UNSPEC) > @@ -32,25 +45,23 @@ sub run_in_userns($;$) { > my $child = sub { > close($sp); > PVE::Tools::unshare(CLONE_NEWUSER | CLONE_NEWNS) or die "unshare(NEWUSER|NEWNS): $!\n"; > - syswrite($sc, "1\n") == 2 or die "write: $!\n"; > + sync_send($sc, "1\n"); > shutdown($sc, 1); > - my $two = <$sc>; > - die "failed to sync with parent process\n" if $two ne "2\n"; > + sync_recv($sc, "2\n"); > close($sc); > $! = undef; > ($(, $)) = (0, 0); > - die "$!\n" if $!; > + die "setgid(0): $!\n" if $!; > ($<, $>) = (0, 0); > - die "$!\n" if $!; > + die "setuid(0): $!\n" if $!; > return $code->(); > }; > my $parent = sub { > my ($pid) = @_; > close($sc); > - my $one = <$sp>; > - die "failed to sync with userprocess\n" if $one ne "1\n"; > + sync_recv($sp, "1\n"); > set_id_map($pid, $id_map); > - syswrite($sp, "2\n") == 2 or die "write: $!\n"; > + sync_send($sp, "2\n"); > close($sp); > }; > PVE::Tools::run_fork($child, { afterfork => $parent }); > -- > 2.47.3