From owner-svn-src-all@FreeBSD.ORG Thu Jan 29 10:40:48 2009 Return-Path: Delivered-To: svn-src-all@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 5CCF4106564A; Thu, 29 Jan 2009 10:40:48 +0000 (UTC) (envelope-from kib@FreeBSD.org) Received: from svn.freebsd.org (svn.freebsd.org [IPv6:2001:4f8:fff6::2c]) by mx1.freebsd.org (Postfix) with ESMTP id 4125C8FC0A; Thu, 29 Jan 2009 10:40:48 +0000 (UTC) (envelope-from kib@FreeBSD.org) Received: from svn.freebsd.org (localhost [127.0.0.1]) by svn.freebsd.org (8.14.3/8.14.3) with ESMTP id n0TAelVA051462; Thu, 29 Jan 2009 10:40:47 GMT (envelope-from kib@svn.freebsd.org) Received: (from kib@localhost) by svn.freebsd.org (8.14.3/8.14.3/Submit) id n0TAel2s051461; Thu, 29 Jan 2009 10:40:47 GMT (envelope-from kib@svn.freebsd.org) Message-Id: <200901291040.n0TAel2s051461@svn.freebsd.org> From: Konstantin Belousov Date: Thu, 29 Jan 2009 10:40:47 +0000 (UTC) To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-stable@freebsd.org, svn-src-stable-7@freebsd.org X-SVN-Group: stable-7 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Cc: Subject: svn commit: r187883 - in stable/7/sys: . contrib/pf dev/cxgb kern X-BeenThere: svn-src-all@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: "SVN commit messages for the entire src tree \(except for " user" and " projects" \)" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 29 Jan 2009 10:40:49 -0000 Author: kib Date: Thu Jan 29 10:40:47 2009 New Revision: 187883 URL: http://svn.freebsd.org/changeset/base/187883 Log: MFC r186896: Do not call namei() while having another user-controlled vnode locked. Lookup could attempt to recursively lock that vnode. Do not call vn_start_write(V_WAIT) while vnode is locked, this may result in a deadlock with suspension. vfs_busy() the mountpoint before dropping vnode lock for vnode that was used to look up the mountpoint, to prevent unmount in between. Modified: stable/7/sys/ (props changed) stable/7/sys/contrib/pf/ (props changed) stable/7/sys/dev/cxgb/ (props changed) stable/7/sys/kern/vfs_extattr.c Modified: stable/7/sys/kern/vfs_extattr.c ============================================================================== --- stable/7/sys/kern/vfs_extattr.c Thu Jan 29 10:33:32 2009 (r187882) +++ stable/7/sys/kern/vfs_extattr.c Thu Jan 29 10:40:47 2009 (r187883) @@ -86,52 +86,65 @@ extattrctl(td, uap) AUDIT_ARG(text, attrname); vfslocked = fnvfslocked = 0; - /* - * uap->filename is not always defined. If it is, grab a vnode lock, - * which VFS_EXTATTRCTL() will later release. - */ + mp = NULL; filename_vp = NULL; if (uap->filename != NULL) { - NDINIT(&nd, LOOKUP, MPSAFE | FOLLOW | LOCKLEAF | - AUDITVNODE2, UIO_USERSPACE, uap->filename, td); + NDINIT(&nd, LOOKUP, MPSAFE | FOLLOW | AUDITVNODE2, + UIO_USERSPACE, uap->filename, td); error = namei(&nd); if (error) return (error); fnvfslocked = NDHASGIANT(&nd); filename_vp = nd.ni_vp; - NDFREE(&nd, NDF_NO_VP_RELE | NDF_NO_VP_UNLOCK); + NDFREE(&nd, NDF_NO_VP_RELE); } /* uap->path is always defined. */ - NDINIT(&nd, LOOKUP, MPSAFE | FOLLOW | AUDITVNODE1, UIO_USERSPACE, - uap->path, td); + NDINIT(&nd, LOOKUP, MPSAFE | FOLLOW | LOCKLEAF | AUDITVNODE1, + UIO_USERSPACE, uap->path, td); error = namei(&nd); - if (error) { - if (filename_vp != NULL) - vput(filename_vp); + if (error) goto out; - } vfslocked = NDHASGIANT(&nd); mp = nd.ni_vp->v_mount; - error = vn_start_write(nd.ni_vp, &mp_writable, V_WAIT | PCATCH); - NDFREE(&nd, 0); + error = vfs_busy(mp, 0, NULL, td); if (error) { - if (filename_vp != NULL) - vput(filename_vp); + NDFREE(&nd, 0); + mp = NULL; goto out; } + VOP_UNLOCK(nd.ni_vp, 0, td); + error = vn_start_write(nd.ni_vp, &mp_writable, V_WAIT | PCATCH); + NDFREE(&nd, NDF_NO_VP_UNLOCK); + if (error) + goto out; + if (filename_vp != NULL) { + /* + * uap->filename is not always defined. If it is, + * grab a vnode lock, which VFS_EXTATTRCTL() will + * later release. + */ + error = vn_lock(filename_vp, LK_EXCLUSIVE, td); + if (error) { + vn_finished_write(mp_writable); + goto out; + } + } error = VFS_EXTATTRCTL(mp, uap->cmd, filename_vp, uap->attrnamespace, uap->attrname != NULL ? attrname : NULL, td); vn_finished_write(mp_writable); +out: + if (mp != NULL) + vfs_unbusy(mp, td); + /* * VFS_EXTATTRCTL will have unlocked, but not de-ref'd, filename_vp, * so vrele it if it is defined. */ if (filename_vp != NULL) vrele(filename_vp); -out: VFS_UNLOCK_GIANT(fnvfslocked); VFS_UNLOCK_GIANT(vfslocked); return (error);