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=-7.0 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable 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 B7917C5B57D for ; Tue, 2 Jul 2019 08:15:42 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 8C8B3205ED for ; Tue, 2 Jul 2019 08:15:42 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1562055342; bh=3sGDtnNNHkSBzik1GPgm8oBEsV9m204Seh2XVrY2XE8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=ownn4L/QD4sodKH0WZFScNWNOReZlbras3kD6s6WaamTK5cUIUc2ylo5t0YGfIoui Xg9dGdG8Qq+ieTSDb1KX2vlODMbh5T7fZ00AmfZ65El+72O4WClTMwLQFZ/BRVUH4S Gn4U0PDaUibmCMhI5Dnxys6tePGoexi32QUXczUU= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727890AbfGBIPg (ORCPT ); Tue, 2 Jul 2019 04:15:36 -0400 Received: from mail.kernel.org ([198.145.29.99]:50390 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727801AbfGBIEn (ORCPT ); Tue, 2 Jul 2019 04:04:43 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 413C621479; Tue, 2 Jul 2019 08:04:42 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1562054682; bh=3sGDtnNNHkSBzik1GPgm8oBEsV9m204Seh2XVrY2XE8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=ZeuacoxgCnQfJ+TNVl+hujKREOyRANyQ+J+hfwTIueNKHEf3kuuUsF+4vdH1MXiTI IDmrfDTsB/bqnlKkxWhMCb7qQUby7eJGKg5urOJV8rIm+vIE9qccPsLPTCYMEDvHsk w9MrxbrhZ0ln5zuDG3pTUuiuUkOVC5ivmPoKIW2o= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Amir Goldstein , Jan Kara , syzbot+c277e8e2f46414645508@syzkaller.appspotmail.com Subject: [PATCH 5.1 54/55] fanotify: update connector fsid cache on add mark Date: Tue, 2 Jul 2019 10:02:02 +0200 Message-Id: <20190702080126.858780989@linuxfoundation.org> X-Mailer: git-send-email 2.22.0 In-Reply-To: <20190702080124.103022729@linuxfoundation.org> References: <20190702080124.103022729@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Amir Goldstein commit c285a2f01d692ef48d7243cf1072897bbd237407 upstream. When implementing connector fsid cache, we only initialized the cache when the first mark added to object was added by FAN_REPORT_FID group. We forgot to update conn->fsid when the second mark is added by FAN_REPORT_FID group to an already attached connector without fsid cache. Reported-and-tested-by: syzbot+c277e8e2f46414645508@syzkaller.appspotmail.com Fixes: 77115225acc6 ("fanotify: cache fsid in fsnotify_mark_connector") Signed-off-by: Amir Goldstein Signed-off-by: Jan Kara Signed-off-by: Greg Kroah-Hartman --- fs/notify/fanotify/fanotify.c | 4 ++++ fs/notify/mark.c | 14 +++++++++++--- include/linux/fsnotify_backend.h | 4 +++- 3 files changed, 18 insertions(+), 4 deletions(-) --- a/fs/notify/fanotify/fanotify.c +++ b/fs/notify/fanotify/fanotify.c @@ -355,6 +355,10 @@ static __kernel_fsid_t fanotify_get_fsid /* Mark is just getting destroyed or created? */ if (!conn) continue; + if (!(conn->flags & FSNOTIFY_CONN_FLAG_HAS_FSID)) + continue; + /* Pairs with smp_wmb() in fsnotify_add_mark_list() */ + smp_rmb(); fsid = conn->fsid; if (WARN_ON_ONCE(!fsid.val[0] && !fsid.val[1])) continue; --- a/fs/notify/mark.c +++ b/fs/notify/mark.c @@ -495,10 +495,13 @@ static int fsnotify_attach_connector_to_ conn->type = type; conn->obj = connp; /* Cache fsid of filesystem containing the object */ - if (fsid) + if (fsid) { conn->fsid = *fsid; - else + conn->flags = FSNOTIFY_CONN_FLAG_HAS_FSID; + } else { conn->fsid.val[0] = conn->fsid.val[1] = 0; + conn->flags = 0; + } if (conn->type == FSNOTIFY_OBJ_TYPE_INODE) inode = igrab(fsnotify_conn_inode(conn)); /* @@ -573,7 +576,12 @@ restart: if (err) return err; goto restart; - } else if (fsid && (conn->fsid.val[0] || conn->fsid.val[1]) && + } else if (fsid && !(conn->flags & FSNOTIFY_CONN_FLAG_HAS_FSID)) { + conn->fsid = *fsid; + /* Pairs with smp_rmb() in fanotify_get_fsid() */ + smp_wmb(); + conn->flags |= FSNOTIFY_CONN_FLAG_HAS_FSID; + } else if (fsid && (conn->flags & FSNOTIFY_CONN_FLAG_HAS_FSID) && (fsid->val[0] != conn->fsid.val[0] || fsid->val[1] != conn->fsid.val[1])) { /* --- a/include/linux/fsnotify_backend.h +++ b/include/linux/fsnotify_backend.h @@ -292,7 +292,9 @@ typedef struct fsnotify_mark_connector _ */ struct fsnotify_mark_connector { spinlock_t lock; - unsigned int type; /* Type of object [lock] */ + unsigned short type; /* Type of object [lock] */ +#define FSNOTIFY_CONN_FLAG_HAS_FSID 0x01 + unsigned short flags; /* flags [lock] */ __kernel_fsid_t fsid; /* fsid of filesystem containing object */ union { /* Object pointer [lock] */