From patchwork Fri May 7 14:03:51 2010 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jeff Layton X-Patchwork-Id: 97724 Received: from lists.samba.org (fn.samba.org [216.83.154.106]) by demeter.kernel.org (8.14.3/8.14.3) with ESMTP id o47E2s2J002156 for ; Fri, 7 May 2010 14:03:30 GMT Received: from fn.samba.org (localhost [127.0.0.1]) by lists.samba.org (Postfix) with ESMTP id A8404AD2F2; Fri, 7 May 2010 08:02:54 -0600 (MDT) X-Spam-Checker-Version: SpamAssassin 3.2.5 (2008-06-10) on fn.samba.org X-Spam-Level: X-Spam-Status: No, score=-9.6 required=3.8 tests=AWL, BAYES_00, RCVD_IN_DNSWL_HI, SPF_HELO_PASS,SPF_PASS autolearn=ham version=3.2.5 X-Original-To: linux-cifs-client@lists.samba.org Delivered-To: linux-cifs-client@lists.samba.org Received: from mx1.redhat.com (mx1.redhat.com [209.132.183.28]) by lists.samba.org (Postfix) with ESMTP id 9B431ACFC9 for ; Fri, 7 May 2010 08:02:48 -0600 (MDT) Received: from int-mx02.intmail.prod.int.phx2.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) by mx1.redhat.com (8.13.8/8.13.8) with ESMTP id o47E2k7W028485 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK); Fri, 7 May 2010 10:02:46 -0400 Received: from localhost.localdomain (vpn2-10-172.ams2.redhat.com [10.36.10.172]) by int-mx02.intmail.prod.int.phx2.redhat.com (8.13.8/8.13.8) with ESMTP id o47E2hpn024460; Fri, 7 May 2010 10:02:44 -0400 From: Jeff Layton To: linux-cifs-client@lists.samba.org Date: Fri, 7 May 2010 16:03:51 +0200 Message-Id: <1273241032-6404-1-git-send-email-jlayton@redhat.com> X-Scanned-By: MIMEDefang 2.67 on 10.5.11.12 Cc: smfrench@gmail.com Subject: [linux-cifs-client] [PATCH] cifs: guard against hardlinking directories X-BeenThere: linux-cifs-client@lists.samba.org X-Mailman-Version: 2.1.12 Precedence: list List-Id: The Linux CIFS VFS client List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Sender: linux-cifs-client-bounces@lists.samba.org Errors-To: linux-cifs-client-bounces@lists.samba.org X-Greylist: IP, sender and recipient auto-whitelisted, not delayed by milter-greylist-4.2.3 (demeter.kernel.org [140.211.167.41]); Fri, 07 May 2010 14:03:30 +0000 (UTC) diff --git a/fs/cifs/cifsglob.h b/fs/cifs/cifsglob.h index ecf0ffb..0c2fd17 100644 --- a/fs/cifs/cifsglob.h +++ b/fs/cifs/cifsglob.h @@ -502,6 +502,7 @@ struct dfs_info3_param { #define CIFS_FATTR_DFS_REFERRAL 0x1 #define CIFS_FATTR_DELETE_PENDING 0x2 #define CIFS_FATTR_NEED_REVAL 0x4 +#define CIFS_FATTR_INO_COLLISION 0x8 struct cifs_fattr { u32 cf_flags; diff --git a/fs/cifs/inode.c b/fs/cifs/inode.c index ee35c97..fb20f11 100644 --- a/fs/cifs/inode.c +++ b/fs/cifs/inode.c @@ -714,6 +714,16 @@ cifs_find_inode(struct inode *inode, void *opaque) if (CIFS_I(inode)->uniqueid != fattr->cf_uniqueid) return 0; + /* + * uh oh -- it's a directory. We can't use it since hardlinked dirs are + * verboten. Disable serverino and return it as if it were found, the + * caller can discard it, generate a uniqueid and retry the find + */ + if (S_ISDIR(inode->i_mode)) { + fattr->cf_flags |= CIFS_FATTR_INO_COLLISION; + cifs_autodisable_serverino(CIFS_SB(inode->i_sb)); + } + return 1; } @@ -733,15 +743,22 @@ cifs_iget(struct super_block *sb, struct cifs_fattr *fattr) unsigned long hash; struct inode *inode; +retry_iget5_locked: cFYI(1, ("looking for uniqueid=%llu", fattr->cf_uniqueid)); /* hash down to 32-bits on 32-bit arch */ hash = cifs_uniqueid_to_ino_t(fattr->cf_uniqueid); inode = iget5_locked(sb, hash, cifs_find_inode, cifs_init_inode, fattr); - - /* we have fattrs in hand, update the inode */ if (inode) { + /* was there a problematic inode number collision? */ + if (fattr->cf_flags & CIFS_FATTR_INO_COLLISION) { + iput(inode); + fattr->cf_uniqueid = iunique(sb, ROOT_I); + fattr->cf_flags &= ~CIFS_FATTR_INO_COLLISION; + goto retry_iget5_locked; + } + cifs_fattr_to_inode(inode, fattr); if (sb->s_flags & MS_NOATIME) inode->i_flags |= S_NOATIME | S_NOCMTIME;