From nobody Thu Feb 06 15:21:54 2025 X-Original-To: bugs@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 4YpgnJ4ZJKz5mc4V for ; Thu, 06 Feb 2025 15:21:56 +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 "R11" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 4YpgnJ3TzVz40TN for ; Thu, 06 Feb 2025 15:21:56 +0000 (UTC) (envelope-from bugzilla-noreply@freebsd.org) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=freebsd.org; s=dkim; t=1738855316; 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: in-reply-to:in-reply-to:references:references; bh=J69xcLBEUy4jCbg8kCPAafC/D/j2sGnWEYyJsZ/5Bbw=; b=YYNIhJXq1mMgc4sv2yQn2jNd2kVLtkby6zPcwchcGEu31vCUg4jF+ZL03Q4yxcTIZNcILj xIrZXW5UAem9oNsTKE6sAt+g2kR5BCqt3mfMf8V+UgGkAt0mWbRH4oO4uJq7VD1MIjrw4c xpi59UvKQPqPbfdO6ej1wkrQNmduwtKmKkfXB2jXH3HD2A4Uo55gvvjsBYaB947WAziOCs VlQS9gS0l43ASJD7Zwny9xYL3XN2SGAJ9YtrNku1/K2yJmT0Tv2d7jZmYO6pQUSvaiOZpk WAU8+rr7erev6E4oz4LQtQ/h8jR2vkApnAmnn8pEuNxNHc9zSanQRjk7OjDLtA== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=freebsd.org; s=dkim; t=1738855316; 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: in-reply-to:in-reply-to:references:references; bh=J69xcLBEUy4jCbg8kCPAafC/D/j2sGnWEYyJsZ/5Bbw=; b=MdifHEoo/CIpc5fHuJmk0w/FEVDfnFvZhvKbe6FeHGovX092lUUViwbteXHFakPrRgXnGQ h2xoPhDc++sYU87DMNlteoyBuVgCvakfAaFLreMusn5GfhRXVIgAvMLmuTfSZMG4tmCvb6 3qLxckOiJfSUbugWOUYcQta1YDdbmLcmX7SGqZ/GlQim/jGQCBDCUNRtgAWRfCHjyhMOBA BxS4IquyJYoRWvMO/tHaFQDpt0bQvsZVQsRk+HwkJ68G1REHpV6kfLcXifzraCW2Wx/oYL GCyTK3/Hi6Ba/cKAiy9Lw+MBWT/wUb2CvPfLVJiEXUi+FqFR+TJQZf+WwY97OQ== ARC-Seal: i=1; s=dkim; d=freebsd.org; t=1738855316; a=rsa-sha256; cv=none; b=kKkB0nqNPtqSE1H2hm+BOpwA0ajdzx6jNeMMvxRqNP+GrkoH4XlsSWDaQIUZfOV/bDJTmC j1dxmWPISL1KypX7SftVrg5qJXrocUHs+Ox3YKfab1W7M79pY6qZFkNmE7Ccs60AN9JxUD yX5BjqTHBynVhOFBikGT7XFLIWJHRRn4evfhfQzJBD4a0egG1HPcsd5s4fjW47/S7OJeRH 1qwQyqGXGvvcIYdzk/nZUbNJgloiMucgvKS+39uwYDtCJq+Z1gaNHB6AUE95mPnTnVEFRx 0ZFbv43fGCxOqEbcNEdf5mV1UQAOXregR3ZYwYYNvnzm4dZCi/dQLX/bM+OR9w== ARC-Authentication-Results: i=1; mx1.freebsd.org; none 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 4YpgnJ34RyzkCn for ; Thu, 06 Feb 2025 15:21:56 +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 516FLuNI007742 for ; Thu, 6 Feb 2025 15:21:56 GMT (envelope-from bugzilla-noreply@freebsd.org) Received: (from www@localhost) by kenobi.freebsd.org (8.15.2/8.15.2/Submit) id 516FLu7K007727 for bugs@FreeBSD.org; Thu, 6 Feb 2025 15:21:56 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: bugs@FreeBSD.org Subject: [Bug 233578] Unprivileged local user can prevent other users logging in by locking utx.active Date: Thu, 06 Feb 2025 15:21:54 +0000 X-Bugzilla-Reason: AssignedTo X-Bugzilla-Type: changed X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: Base System X-Bugzilla-Component: bin X-Bugzilla-Version: CURRENT X-Bugzilla-Keywords: needs-qa, security X-Bugzilla-Severity: Affects Many People X-Bugzilla-Who: cross@gajendra.net X-Bugzilla-Status: Open X-Bugzilla-Resolution: X-Bugzilla-Priority: Normal X-Bugzilla-Assigned-To: bugs@FreeBSD.org X-Bugzilla-Flags: maintainer-feedback? X-Bugzilla-Changed-Fields: cc Message-ID: In-Reply-To: References: Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="UTF-8" X-Bugzilla-URL: https://bugs.freebsd.org/bugzilla/ Auto-Submitted: auto-generated List-Id: Bug reports List-Archive: https://lists.freebsd.org/archives/freebsd-bugs List-Help: List-Post: List-Subscribe: List-Unsubscribe: Sender: owner-freebsd-bugs@FreeBSD.org MIME-Version: 1.0 https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=3D233578 Dan Cross changed: What |Removed |Added ---------------------------------------------------------------------------- CC| |cross@gajendra.net --- Comment #10 from Dan Cross --- This has come up for me recently, on a multiuser system where (by design) n= ot all of the accounts are completely trusted. Unprivileged users preventing logins is unacceptable, but it would be a shame to de-permit access to utx.active, thus making programs like `finger`, `w`, or `who` or other consumers of the `getutxent` interface uninteresting. The proposal in #4 seems reasonable; is there any chance this could be appl= ied any time soonish? Btw, looking at the code in `pututxline`, the algorithm for updating lastlog appears to be linear in the number of users on the system. We've got tens of thousands of users, making this very slow; other systems use the uid as an index into that file (which may be sparse as a result, but that's ok). Woul= d it be possible to do that here? Also, we used to have a program that (effectively) tail -f'ed the wtmp file= and would print out a message when someone in a user-selectable list logged in = or out; our users enjoyed that. But there's no way to accommodate that in the current framework, which is a shame. Part of this is due to the data format being opaque, and part of it is inadequacies in the API (there's no way to = use e.g., `setutxdb` and then seek to the end of a file). It's a bit of a sham= e. --=20 You are receiving this mail because: You are the assignee for the bug.=