From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id C76BDC433DB for ; Sat, 13 Mar 2021 04:41:29 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 9E49364F66 for ; Sat, 13 Mar 2021 04:41:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233170AbhCMEk6 (ORCPT ); Fri, 12 Mar 2021 23:40:58 -0500 Received: from zeniv-ca.linux.org.uk ([142.44.231.140]:33584 "EHLO zeniv-ca.linux.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233160AbhCMEkg (ORCPT ); Fri, 12 Mar 2021 23:40:36 -0500 Received: from viro by zeniv-ca.linux.org.uk with local (Exim 4.94 #2 (Red Hat Linux)) id 1lKw2j-005O03-F1; Sat, 13 Mar 2021 04:38:25 +0000 From: Al Viro To: Linus Torvalds Cc: linux-fsdevel@vger.kernel.org, Jeff Layton , David Howells , Hans de Goede , Mike Marshall , Joseph Qi , Bob Peterson , Steve French , Richard Weinberger , Dominique Martinet , Arnd Bergmann Subject: [PATCH v2 10/15] cifs: have ->mkdir() handle race with another client sanely Date: Sat, 13 Mar 2021 04:38:19 +0000 Message-Id: <20210313043824.1283821-10-viro@zeniv.linux.org.uk> X-Mailer: git-send-email 2.29.2 In-Reply-To: <20210313043824.1283821-1-viro@zeniv.linux.org.uk> References: <20210313043824.1283821-1-viro@zeniv.linux.org.uk> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: Al Viro Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org if we have mkdir request reported successful *and* simulating lookup gets us a non-directory (which is possible if another client has managed to get rmdir and create in between), the sane action is not to mangle ->i_mode of non-directory inode to S_IFDIR | mode, it's "report success and return with dentry negative unhashed" - that way the next lookup will do the right thing. Signed-off-by: Al Viro --- fs/cifs/inode.c | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-) diff --git a/fs/cifs/inode.c b/fs/cifs/inode.c index d46b36d52211..80c487fcf10e 100644 --- a/fs/cifs/inode.c +++ b/fs/cifs/inode.c @@ -1739,6 +1739,16 @@ cifs_mkdir_qinfo(struct inode *parent, struct dentry *dentry, umode_t mode, if (rc) return rc; + if (!S_ISDIR(inode->i_mode)) { + /* + * mkdir succeeded, but another client has managed to remove the + * sucker and replace it with non-directory. Return success, + * but don't leave the child in dcache. + */ + iput(inode); + d_drop(dentry); + return 0; + } /* * setting nlink not necessary except in cases where we failed to get it * from the server or was set bogus. Also, since this is a brand new @@ -1790,7 +1800,7 @@ cifs_mkdir_qinfo(struct inode *parent, struct dentry *dentry, umode_t mode, } } d_instantiate(dentry, inode); - return rc; + return 0; } static int -- 2.11.0