Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932450AbbGPBY1 (ORCPT ); Wed, 15 Jul 2015 21:24:27 -0400 Received: from youngberry.canonical.com ([91.189.89.112]:56225 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932168AbbGPBLo (ORCPT ); Wed, 15 Jul 2015 21:11:44 -0400 From: Kamal Mostafa To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Cc: Jan Kara , Al Viro , Kamal Mostafa Subject: [PATCH 3.19.y-ckt 212/251] ufs: Fix possible deadlock when looking up directories Date: Wed, 15 Jul 2015 18:08:53 -0700 Message-Id: <1437008972-9140-213-git-send-email-kamal@canonical.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1437008972-9140-1-git-send-email-kamal@canonical.com> References: <1437008972-9140-1-git-send-email-kamal@canonical.com> X-Extended-Stable: 3.19 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1709 Lines: 49 3.19.8-ckt4 -stable review patch. If anyone has any objections, please let me know. ------------------ From: Jan Kara commit 514d748f69c97a51a2645eb198ac5c6218f22ff9 upstream. Commit e4502c63f56aeca88 (ufs: deal with nfsd/iget races) made ufs create inodes with I_NEW flag set. However ufs_mkdir() never cleared this flag. Thus if someone ever tried to lookup the directory by inode number, he would deadlock waiting for I_NEW to be cleared. Luckily this mostly happens only if the filesystem is exported over NFS since otherwise we have the inode attached to dentry and don't look it up by inode number. In rare cases dentry can get freed without inode being freed and then we'd hit the deadlock even without NFS export. Fix the problem by clearing I_NEW before instantiating new directory inode. Fixes: e4502c63f56aeca887ced37f24e0def1ef11cec8 Reported-by: Fabian Frederick Signed-off-by: Jan Kara Signed-off-by: Al Viro Signed-off-by: Kamal Mostafa --- fs/ufs/namei.c | 1 + 1 file changed, 1 insertion(+) diff --git a/fs/ufs/namei.c b/fs/ufs/namei.c index 6515899..73644c6 100644 --- a/fs/ufs/namei.c +++ b/fs/ufs/namei.c @@ -207,6 +207,7 @@ static int ufs_mkdir(struct inode * dir, struct dentry * dentry, umode_t mode) goto out_fail; unlock_ufs(dir->i_sb); + unlock_new_inode(inode); d_instantiate(dentry, inode); out: return err; -- 1.9.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/