From nobody Thu Dec 07 04:16:26 2023 X-Original-To: standards@mlmmj.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mlmmj.nyi.freebsd.org (Postfix) with ESMTP id 4Sm1DV2cvbz53XLD for ; Thu, 7 Dec 2023 04:16:26 +0000 (UTC) (envelope-from bugzilla-noreply@freebsd.org) Received: from mxrelay.nyi.freebsd.org (mxrelay.nyi.freebsd.org [IPv6:2610:1c1:1:606c::19:3]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256 client-signature RSA-PSS (4096 bits) client-digest SHA256) (Client CN "mxrelay.nyi.freebsd.org", Issuer "R3" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 4Sm1DV05kmz3KwN for ; Thu, 7 Dec 2023 04:16:26 +0000 (UTC) (envelope-from bugzilla-noreply@freebsd.org) ARC-Seal: i=1; s=dkim; d=freebsd.org; t=1701922586; a=rsa-sha256; cv=none; b=QsfVc5168E6yqAVymVB/KfFqKoK8jJfpHtV1MIZ1U3X4sn8HWY4zBg09rDQdsNssyX/Wu2 GtoRcAjmQymA5gG/fPJW27t6FxAPz5/ij7ZW5VVeDMAId42lxD1B7NuNRrG/vLg/msTHaI FSoBzIb2FRPChtlb45odJydZTxH8sV3jcRHCXDjz5lGMrIpAe7V4DG1t8W6/mv+dsXgz+i Jhslxv3Lf5A6ZwyuqZ8yh/lHWQlNVhf1HcCVwZdScCHOySG1h9GQHbEhfzOWGFeMePmzqh KOu0AUBJ9/WPjSYF6QsyAL8wcKpD786EL7qZ07di9kvTmgeUgX9fTX1pGud0Gg== ARC-Authentication-Results: i=1; mx1.freebsd.org; none ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=freebsd.org; s=dkim; t=1701922586; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding; bh=A6UmalEz+KU+625sx/fW9RlVKI/L1rksdMtfKb241lk=; b=SoC5ZknMu3v/L1nI+8pP9L0jFywjocD78zkRY4RINHGjtZOf/TApWTlctMR/+d+SgbO+gq aUwrNofGMMuX9wfLZqNhG23/4M2xO43QpPPzvKpduC98KVZqVgZuOaRz033AxvKa8dsbup uSjnjzAKBz/oW4yQqfl2UWhcNRabpnIpbKbtHXBI51EXbaBpwYKz+eSv/Y6soj9XrryBHO b6eYrGpXa5scHzblB5dVLm0T6zOoB118vscKX0UsljVs7khPdd/LbFVj83IDiEQTQqdail kWkji+ssvyZAJ3UNa1UnLu3nF7rBUiQ0RPIjwkX61ItGMJ7Mj+pxDyX3yz368Q== Received: from kenobi.freebsd.org (kenobi.freebsd.org [IPv6:2610:1c1:1:606c::50:1d]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (Client did not present a certificate) by mxrelay.nyi.freebsd.org (Postfix) with ESMTPS id 4Sm1DT6DxWz6wl for ; Thu, 7 Dec 2023 04:16:25 +0000 (UTC) (envelope-from bugzilla-noreply@freebsd.org) Received: from kenobi.freebsd.org ([127.0.1.5]) by kenobi.freebsd.org (8.15.2/8.15.2) with ESMTP id 3B74GPlO078445 for ; Thu, 7 Dec 2023 04:16:25 GMT (envelope-from bugzilla-noreply@freebsd.org) Received: (from www@localhost) by kenobi.freebsd.org (8.15.2/8.15.2/Submit) id 3B74GPAa078444 for standards@FreeBSD.org; Thu, 7 Dec 2023 04:16:25 GMT (envelope-from bugzilla-noreply@freebsd.org) X-Authentication-Warning: kenobi.freebsd.org: www set sender to bugzilla-noreply@freebsd.org using -f From: bugzilla-noreply@freebsd.org To: standards@FreeBSD.org Subject: [Bug 275586] Undocumented feature of ifconfig UP Date: Thu, 07 Dec 2023 04:16:26 +0000 X-Bugzilla-Reason: AssignedTo X-Bugzilla-Type: new X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: Base System X-Bugzilla-Component: standards X-Bugzilla-Version: Unspecified X-Bugzilla-Keywords: X-Bugzilla-Severity: Affects Only Me X-Bugzilla-Who: on@cs.ait.ac.th X-Bugzilla-Status: New X-Bugzilla-Resolution: X-Bugzilla-Priority: --- X-Bugzilla-Assigned-To: standards@FreeBSD.org X-Bugzilla-Flags: X-Bugzilla-Changed-Fields: bug_id short_desc product version rep_platform op_sys bug_status bug_severity priority component assigned_to reporter Message-ID: Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Bugzilla-URL: https://bugs.freebsd.org/bugzilla/ Auto-Submitted: auto-generated List-Id: Standards compliance List-Archive: https://lists.freebsd.org/archives/freebsd-standards List-Help: List-Post: List-Subscribe: List-Unsubscribe: Sender: owner-freebsd-standards@freebsd.org X-BeenThere: freebsd-standards@freebsd.org MIME-Version: 1.0 https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=3D275586 Bug ID: 275586 Summary: Undocumented feature of ifconfig UP Product: Base System Version: Unspecified Hardware: Any OS: Any Status: New Severity: Affects Only Me Priority: --- Component: standards Assignee: standards@FreeBSD.org Reporter: on@cs.ait.ac.th I am not sure whether it is an undocumented feature or a bug but "ifconfig = UP" behaves differently from "ifconfig up". I cannot say for how long this behaviour has been going on, I only recently discovered it, but it is affec= ting any 13.2-p5 RELEASE system I have tested. To reproduce the problem: "ifconfig up" is working as documented/expected: $ ifconfig tap0 create $ ifconfig tap0 up $ ifconfig tap0 tap0: flags=3D8803 metric 0 mtu 1500 options=3D80000 ether 58:9c:fc:10:a4:65 groups: tap media: Ethernet autoselect status: no carrier nd6 options=3D29 $ arp -a | grep 192.41.170.42 While "ifconfig UP" is acting up: Reboot the system, then... $ ifconfig tap0 create $ ifconfig tap0 UP ifconfig: WARNING: setting interface address without mask is deprecated, default mask may not be correct. $ ifconfig tap0 tap0: flags=3D8843 metric 0 mtu 1500 options=3D80000 ether 58:9c:fc:10:a4:65 inet 192.41.170.42 netmask 0xffffff00 broadcast 192.41.170.255 groups: tap media: Ethernet autoselect status: no carrier nd6 options=3D29 $ arp -a | grep 192.41.170.42 www.cs.ait.ac.th (192.41.170.42) at 58:9c:fc:10:a4:65 on tap0 permanent [ethernet] An IP address has been assigned to the tap0 interface (it happens to be the= IP of my web server, why?) even though the tap0 interface is not yet connected= to anything. As a corollary, the machine may respond to ARP requests, giving a bogus MAC address for the IP 192.41.170.42 and causing problems on my network. Solution: Always use "ifconfig up". But if it gives weird results and if not document= ed, why keeping "ifconfig UP". I have not tested it, but it seems there is also a problem with "ifconfig D= OWN" vs. "ifconfig down". --=20 You are receiving this mail because: You are the assignee for the bug.=