From nobody Tue Sep 29 15:56:41 2026 X-Original-To: dev-commits-src-all@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 4hvN8T4z4Zz6tl9C for ; Tue, 29 Sep 2026 15:56:41 +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 "YR2" (not verified)) by mx1.freebsd.org (Postfix) with ESMTPS id 4hvN8T2l5yz4W4V for ; Tue, 29 Sep 2026 15:56:41 +0000 (UTC) (envelope-from git@FreeBSD.org) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=freebsd.org; s=dkim; t=1790697401; 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=Ofp7hYqWVOuZJ6bIDYxoy25+HWd07/NCRKUWUPPQeOA=; b=RtkJ86tOA4nbS+3S1bYYaD6QEiKe6ng13RZOY1TraVlCiUelczaFaQ57tnqbmUoP4v+IZp tx9AlJrE0arYXiD1ix+F5jhbRzkljbbdjR69L/gEruinJ8bCqWyzzoQrkqT6Y8VKdjd9LA E4VlYTc+/bjpOuH95ngXzPa7qU9rlDBOv/HO8aPdn7Hw0pRbmanq8zpCVDt4+daSYsuxVr IJngxNIFGv6FID7waiUwLFnNw8Jy0KQKwOnv5aIilYrLrV4dEF6hzliMjdytGnBxSZikXu Mum7wAm81j5023irVyYDdAAezITUG/hz5qbfZApVP7dMQ932JOlcn1ZYYU1SMg== ARC-Seal: i=1; a=rsa-sha256; d=freebsd.org; s=dkim; cv=none; t=1790697401; b=W8dqJBEWqNzx2YJMHYL7y7ZvopvztPqfnglGLjtlQvgDgGbKTS1gNM98qa62wWtSp0caiD 6QkOhzP+Dw6+q5h7q4xbVou/LgE832/r5SxeBp8Ox52etUyf//m72DUxhDROa5+WqtGJs4 x17Zc6UsrSvuChW2wM3/cuxtCCFpbWLimvcWBqkHS8Tsmw4C740yLbTGfysk2rAwN4kWSU +4WRFpTysfJFyylfD6S7TApMp+tFKPYUOLntpKYBnpBiahz+UDZ9h4xXRQn2tm8bveW1mj /3FURwNUJ6XetGon43Cowd7KFBPaDDnxB2JIJfJy6z7kAH0jN4a7qxmhz5g+1g== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=freebsd.org; s=dkim; t=1790697401; 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=Ofp7hYqWVOuZJ6bIDYxoy25+HWd07/NCRKUWUPPQeOA=; b=iHObSTLEwBifAV4LsRN3RMCm0IZrvAOdJ7AF9ZTY3fgOzJyP/qdoPCBFLkWohbANksyo7q HHnLD4FEBYUubNEeOncZ8eLLzj2NxjbkSzILpfKk/MqTu6BK7fkN4kqIY8LpD7xvq9dWZt +pBAhp0akW5jMwd/ipY3UG4D0BfPLki40ZZ3hsKJGrP8O//74oF8LQyqrjrBKToSVdDHfR 7SNlNxnlORyiR9z4G7wpcO/UOP7zPKlN3mRDoYz7s9hajcFzYIBby/Y7unl4INAh7xkiOF CwfPA91tYdtjskRZfb82zUuN2afYCj6InhBddiuYsqWxguwQnGBsAbctrapnaw== ARC-Authentication-Results: i=1; mx1.freebsd.org; none Received: from gitrepo.freebsd.org (gitrepo.freebsd.org [IPv6:2610:1c1:1:6068::e6a:5]) by mxrelay.nyi.freebsd.org (Postfix) with ESMTP id 4hvN8T1LZ3z1KPC for ; Tue, 29 Sep 2026 15:56:41 +0000 (UTC) (envelope-from git@FreeBSD.org) Received: from git (uid 1279) (envelope-from git@FreeBSD.org) id 279e7 by gitrepo.freebsd.org (DragonFly Mail Agent v0.13+ on gitrepo.freebsd.org); Tue, 29 Sep 2026 15:56:41 +0000 To: src-committers@FreeBSD.org, dev-commits-src-all@FreeBSD.org, dev-commits-src-branches@FreeBSD.org From: Mark Johnston Subject: git: 666f08d59743 - stable/14 - vfs: Disallow renameat() with FD_RESOLVE_BENEATH descriptors List-Id: Commit messages for all branches of the src repository List-Archive: https://lists.freebsd.org/archives/dev-commits-src-all List-Help: List-Post: List-Subscribe: List-Unsubscribe: X-BeenThere: dev-commits-src-all@freebsd.org Sender: owner-dev-commits-src-all@FreeBSD.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit X-Git-Committer: markj X-Git-Repository: src X-Git-Refname: refs/heads/stable/14 X-Git-Reftype: branch X-Git-Commit: 666f08d597436ad709fabc04e618e9228ec96e74 Auto-Submitted: auto-generated Date: Tue, 29 Sep 2026 15:56:41 +0000 Message-Id: <6abbdfb9.279e7.600d2692@gitrepo.freebsd.org> The branch stable/14 has been updated by markj: URL: https://cgit.FreeBSD.org/src/commit/?id=666f08d597436ad709fabc04e618e9228ec96e74 commit 666f08d597436ad709fabc04e618e9228ec96e74 Author: Mark Johnston AuthorDate: 2026-09-28 16:47:56 +0000 Commit: Mark Johnston CommitDate: 2026-09-29 15:56:32 +0000 vfs: Disallow renameat() with FD_RESOLVE_BENEATH descriptors The FD_RESOLVE_BENEATH flag was intended to try to resolve bugzilla PR 262179 without entirely disallowing fd passing between jails. However, one can use renameat() to bypass the restriction: upon receiving a directory fd with FD_RESOLVE_BENEATH set, a jailed process can still move its CWD or one of its ancestors to the directory, and just cd out of its jail root. So disallow renameat() when either the source or destination directory fds has FD_RESOLVE_BENEATH set, like we do with fchdir() and fchroot() to prevent similar escapes. Approved by: so Security: FreeBSD-SA-26:66.jail Security: CVE-2026-101305 PR: 262179 Reported by: firk@cantconnect.ru Reviewed by: olce, kib Differential Revision: https://reviews.freebsd.org/D59875 --- lib/libc/sys/fcntl.2 | 9 ++++++++- sys/kern/vfs_syscalls.c | 9 +++++++++ 2 files changed, 17 insertions(+), 1 deletion(-) diff --git a/lib/libc/sys/fcntl.2 b/lib/libc/sys/fcntl.2 index fdd29c9f5d78..427ae28dcfd6 100644 --- a/lib/libc/sys/fcntl.2 +++ b/lib/libc/sys/fcntl.2 @@ -27,7 +27,7 @@ .\" .\" @(#)fcntl.2 8.2 (Berkeley) 1/12/94 .\" -.Dd June 5, 2025 +.Dd September 22, 2026 .Dt FCNTL 2 .Os .Sh NAME @@ -150,6 +150,13 @@ and similar operations, and opening a directory with .Xr openat 2 where the directory descriptor has the flag set causes the new directory descriptor to also have the flag set. +A file descriptor with the +.Dv FD_RESOLVE_BENEATH +set cannot be used as either the source or target descriptor in +.Xr renameat 2 +or +.Xr renameat2 2 +system calls. .El .It Dv F_SETFD Set flags associated with diff --git a/sys/kern/vfs_syscalls.c b/sys/kern/vfs_syscalls.c index de2261256875..f261e3457122 100644 --- a/sys/kern/vfs_syscalls.c +++ b/sys/kern/vfs_syscalls.c @@ -3725,6 +3725,15 @@ again: } tdvp = tond.ni_dvp; tvp = tond.ni_vp; + if (fvp->v_type == VDIR && + ((fromnd.ni_resflags | tond.ni_resflags) & NIRES_BENEATH) != 0) { + /* + * We must not rename a directory relative to FD_RESOLVE_BENEATH + * descriptors. + */ + error = ENOTCAPABLE; + goto out; + } error = vn_start_write(fvp, &mp, V_NOWAIT); if (error != 0) { NDFREE_PNBUF(&fromnd);