From nobody Thu Feb 29 13:17:45 2024 X-Original-To: dev-commits-src-branches@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 4TlsGL10GNz5C9WR; Thu, 29 Feb 2024 13:17:46 +0000 (UTC) (envelope-from git@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 4TlsGL0Y1hz4Z2p; Thu, 29 Feb 2024 13:17:46 +0000 (UTC) (envelope-from git@FreeBSD.org) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=freebsd.org; s=dkim; t=1709212666; 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=L7o94gMPU78ROKa8/EAN1YhX5gPAo1NvLmYPZLHGP3k=; b=WbWOYY58eZYzYz5Jkk9HmN2R1JJCM2Z94OhtJQw85PsRI4FZFfLPReBXcvjm7IrVYl6cNr AoUK0TkKiqf9O2mmc9m4B7eA4MNmOOYYXfY69iT4as/zF1P9Q03IBx1UgjHP9SgjSGcS0D Bav4O47CLaiyUjX+GrPNdhLZSjqnq8JO12hoOS344tsWFM0PDhktvuFW8cRoxbs1gkTDR0 qixIst9EwlYLxaBSyIEPHCYDmOx5EjamQiO0bi3FR5Dk7Boou2AQHJVK5JdJwKVVfjNKAu 8sudTf7GKZhL53GhL3HTqimH12PT6uLzWUq1o4xsATepIByJuRIzX2IWeH/rww== ARC-Seal: i=1; s=dkim; d=freebsd.org; t=1709212666; a=rsa-sha256; cv=none; b=D973mnBVx7KDBqd5fULln9q6UhgQuJkmusF2HX26y8fwkN8a1qDfEv9utjQWnkxjhGS7Zm Qa85Jr9p8n0ZR2gLIWTysPVw5EFGgydphkHQyHui2gW8/99bko1KQHwX6/nBeH+2p6zbgi NrguWDbmxCievz/MlbjxMl87pwEc31jacbm/aMyu31vdxLQkqjuIufYmpz1n3NDcTv3p64 3NGanm9/sOlgzPUArtKmAkbQJWK6Zhar3TOzcW97wF0fwD+/Y1F6mYefh0oe5h24ulsVcW PDHg7WfmQVTINzZDtVkNa09F7JY7pnmOvQWegHGu39l8XvrFa99M2gI1u81CLA== 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=1709212666; 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=L7o94gMPU78ROKa8/EAN1YhX5gPAo1NvLmYPZLHGP3k=; b=p2jy7MGVbqAhmj1MmXh5F7V95A2+b0PnPWDzTYcEO8q1j/SloTTcRTi2FtPiDxI3OQbBWb BKTdjvoQxN+GULCpfjr8Qp612MUtV+TVeKSHa+0cZYi094qonIOl1BATU/H5isjyFQbrP1 FHU+q/mjPFPe//trRGXlu3vurh9NyEupVmMrHVdIxXFLViS5uiEgWs76yyVHPZyzynZdTq XGze4qbzhF0dseG9kEczetEgOOVKdSQCX5KtmvClyfu8EJj5dGKjfCykTuymyrICovyBfc OF+nj8dXeX/jQBBe9ZmXt9IlYegLxc4TmzLZx0hmWz1lyvxHx/3kE3xttERqEQ== Received: from gitrepo.freebsd.org (gitrepo.freebsd.org [IPv6:2610:1c1:1:6068::e6a:5]) (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 4TlsGL09PVzjmQ; Thu, 29 Feb 2024 13:17:46 +0000 (UTC) (envelope-from git@FreeBSD.org) Received: from gitrepo.freebsd.org ([127.0.1.44]) by gitrepo.freebsd.org (8.17.1/8.17.1) with ESMTP id 41TDHjKs004410; Thu, 29 Feb 2024 13:17:45 GMT (envelope-from git@gitrepo.freebsd.org) Received: (from git@localhost) by gitrepo.freebsd.org (8.17.1/8.17.1/Submit) id 41TDHjKr004407; Thu, 29 Feb 2024 13:17:45 GMT (envelope-from git) Date: Thu, 29 Feb 2024 13:17:45 GMT Message-Id: <202402291317.41TDHjKr004407@gitrepo.freebsd.org> To: src-committers@FreeBSD.org, dev-commits-src-all@FreeBSD.org, dev-commits-src-branches@FreeBSD.org From: Ed Maste Subject: git: 784695750ef3 - releng/13.3 - jail: Fix information leak. List-Id: Commits to the stable branches of the FreeBSD src repository List-Archive: https://lists.freebsd.org/archives/dev-commits-src-branches List-Help: List-Post: List-Subscribe: List-Unsubscribe: Sender: owner-dev-commits-src-branches@freebsd.org X-BeenThere: dev-commits-src-branches@freebsd.org MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit X-Git-Committer: emaste X-Git-Repository: src X-Git-Refname: refs/heads/releng/13.3 X-Git-Reftype: branch X-Git-Commit: 784695750ef3f73dec38150617684b9f757c787d Auto-Submitted: auto-generated The branch releng/13.3 has been updated by emaste: URL: https://cgit.FreeBSD.org/src/commit/?id=784695750ef3f73dec38150617684b9f757c787d commit 784695750ef3f73dec38150617684b9f757c787d Author: Pawel Jakub Dawidek AuthorDate: 2024-01-17 17:43:55 +0000 Commit: Ed Maste CommitDate: 2024-02-29 13:16:30 +0000 jail: Fix information leak. There is a lack of proper visibility checking in kern.ttys sysctl handler which leads to information leak about processes outside the current jail. This can be demonstrated with pstat -t: when called from within a jail, it will output all terminal devices including process groups and session leader process IDs: jail# pstat -t | grep pts/ | head LINE INQ CAN LIN LOW OUTQ USE LOW COL SESS PGID STATE pts/2 1920 0 0 192 1984 0 199 0 4132 27245 Oi pts/3 1920 0 0 192 1984 0 199 16 24890 33627 Oi pts/5 0 0 0 0 0 0 0 25 17758 0 G pts/16 0 0 0 0 0 0 0 0 52495 0 G pts/15 0 0 0 0 0 0 0 25 53446 0 G pts/17 0 0 0 0 0 0 0 6702 33230 0 G pts/19 0 0 0 0 0 0 0 14 1116 0 G pts/0 0 0 0 0 0 0 0 0 2241 0 G pts/23 0 0 0 0 0 0 0 20 15639 0 G pts/6 0 0 0 0 0 0 0 0 44062 93792 G jail# pstat -t | grep pts/ | wc -l 85 Devfs does the filtering correctly and we get only one entry: jail# ls /dev/pts/ 2 Approved by: mzaborski, secteam MFC after: 1 week Sponsored by: Fudo Security (cherry picked from commit f1d0a0cbecf2c688061f35adea85bfb29c9ec893) (cherry picked from commit a376108029a20f4ce51476d98f2483a7008ce7b5) (cherry picked from commit 41ac0b4ce00bae061164384f23356a4df6e0e695) (cherry picked from commit 9bff7ec98354a76c171905ce9530f85685725ee7) Approved by: re (cperciva) --- sys/kern/tty.c | 26 ++++++++++++++++++++++---- 1 file changed, 22 insertions(+), 4 deletions(-) diff --git a/sys/kern/tty.c b/sys/kern/tty.c index d7f9a914166a..508c0f14b861 100644 --- a/sys/kern/tty.c +++ b/sys/kern/tty.c @@ -44,6 +44,7 @@ #ifdef COMPAT_43TTY #include #endif /* COMPAT_43TTY */ +#include #include #include #include @@ -1308,9 +1309,11 @@ static int sysctl_kern_ttys(SYSCTL_HANDLER_ARGS) { unsigned long lsize; + struct thread *td = curthread; struct xtty *xtlist, *xt; struct tty *tp; - int error; + struct proc *p; + int cansee, error; sx_slock(&tty_list_sx); lsize = tty_list_count * sizeof(struct xtty); @@ -1323,13 +1326,28 @@ sysctl_kern_ttys(SYSCTL_HANDLER_ARGS) TAILQ_FOREACH(tp, &tty_list, t_list) { tty_lock(tp); - tty_to_xtty(tp, xt); + if (tp->t_session != NULL) { + p = tp->t_session->s_leader; + PROC_LOCK(p); + cansee = (p_cansee(td, p) == 0); + PROC_UNLOCK(p); + } else { + cansee = !jailed(td->td_ucred); + } + if (cansee) { + tty_to_xtty(tp, xt); + xt++; + } tty_unlock(tp); - xt++; } sx_sunlock(&tty_list_sx); - error = SYSCTL_OUT(req, xtlist, lsize); + lsize = (xt - xtlist) * sizeof(struct xtty); + if (lsize > 0) { + error = SYSCTL_OUT(req, xtlist, lsize); + } else { + error = 0; + } free(xtlist, M_TTY); return (error); }