From patchwork Mon Apr 26 18:41:55 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Gabriel Krisman Bertazi X-Patchwork-Id: 12224863 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,UNPARSEABLE_RELAY,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 D5D29C433B4 for ; Mon, 26 Apr 2021 18:43:19 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B18BA613BF for ; Mon, 26 Apr 2021 18:43:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239510AbhDZSn7 (ORCPT ); Mon, 26 Apr 2021 14:43:59 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:47668 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237860AbhDZSnk (ORCPT ); Mon, 26 Apr 2021 14:43:40 -0400 Received: from bhuna.collabora.co.uk (bhuna.collabora.co.uk [IPv6:2a00:1098:0:82:1000:25:2eeb:e3e3]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C20E5C06175F; Mon, 26 Apr 2021 11:42:57 -0700 (PDT) Received: from [127.0.0.1] (localhost [127.0.0.1]) (Authenticated sender: krisman) with ESMTPSA id 67AB21F41E27 From: Gabriel Krisman Bertazi To: amir73il@gmail.com, tytso@mit.edu, djwong@kernel.org Cc: david@fromorbit.com, jack@suse.com, dhowells@redhat.com, khazhy@google.com, linux-fsdevel@vger.kernel.org, linux-ext4@vger.kernel.org, Gabriel Krisman Bertazi , kernel@collabora.com Subject: [PATCH RFC 09/15] fanotify: Introduce generic error record Date: Mon, 26 Apr 2021 14:41:55 -0400 Message-Id: <20210426184201.4177978-10-krisman@collabora.com> X-Mailer: git-send-email 2.31.0 In-Reply-To: <20210426184201.4177978-1-krisman@collabora.com> References: <20210426184201.4177978-1-krisman@collabora.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org This record describes a fs error in a fs agnostic way. It will be send back to userspace in response to a FSNOTIFY_EVENT_ERROR for groups with the FAN_ERROR mark. Signed-off-by: Gabriel Krisman Bertazi --- fs/notify/fanotify/fanotify.h | 16 ++++++++++++++++ fs/notify/fanotify/fanotify_user.c | 28 ++++++++++++++++++++++++++++ include/uapi/linux/fanotify.h | 10 ++++++++++ 3 files changed, 54 insertions(+) diff --git a/fs/notify/fanotify/fanotify.h b/fs/notify/fanotify/fanotify.h index 47299e3d6efd..4cb9dd31f084 100644 --- a/fs/notify/fanotify/fanotify.h +++ b/fs/notify/fanotify/fanotify.h @@ -179,6 +179,22 @@ FANOTIFY_NE(struct fanotify_event *event) return container_of(event, struct fanotify_name_event, fae); } +struct fanotify_error_event { + struct fanotify_event fae; + int error; + __kernel_fsid_t fsid; + + int fs_data_size; + /* Must be the last item in the structure */ + char fs_data[0]; +}; + +static inline struct fanotify_error_event * +FANOTIFY_EE(struct fanotify_event *event) +{ + return container_of(event, struct fanotify_error_event, fae); +} + static inline __kernel_fsid_t *fanotify_event_fsid(struct fanotify_event *event) { if (event->type == FANOTIFY_EVENT_TYPE_FID) diff --git a/fs/notify/fanotify/fanotify_user.c b/fs/notify/fanotify/fanotify_user.c index 5031198bf7db..21162d347bd1 100644 --- a/fs/notify/fanotify/fanotify_user.c +++ b/fs/notify/fanotify/fanotify_user.c @@ -64,6 +64,11 @@ static int fanotify_fid_info_len(int fh_len, int name_len) return roundup(FANOTIFY_INFO_HDR_LEN + info_len, FANOTIFY_EVENT_ALIGN); } +static size_t fanotify_error_info_len(struct fanotify_error_event *fee) +{ + return sizeof(struct fanotify_event_info_error); +} + static size_t fanotify_event_len(struct fanotify_event *event, unsigned int fid_mode) { @@ -232,6 +237,29 @@ static int process_access_response(struct fsnotify_group *group, return -ENOENT; } +static size_t copy_error_info_to_user(struct fanotify_error_event *fee, + char __user *buf, int count) +{ + struct fanotify_event_info_error info; + + info.hdr.info_type = FAN_EVENT_INFO_TYPE_ERROR; + info.hdr.pad = 0; + info.hdr.len = fanotify_error_info_len(fee); + + if (WARN_ON(count < info.hdr.len)) + return -EFAULT; + + info.version = FANOTIFY_EVENT_INFO_ERROR_VERS_1; + info.error = fee->error; + info.fsid = fee->fsid; + + if (copy_to_user(buf, &info, sizeof(info))) + return -EFAULT; + + return info.hdr.len; + +} + static int copy_info_to_user(__kernel_fsid_t *fsid, struct fanotify_fh *fh, int info_type, const char *name, size_t name_len, char __user *buf, size_t count) diff --git a/include/uapi/linux/fanotify.h b/include/uapi/linux/fanotify.h index b283531549f1..cc9a1fa80e30 100644 --- a/include/uapi/linux/fanotify.h +++ b/include/uapi/linux/fanotify.h @@ -124,6 +124,7 @@ struct fanotify_event_metadata { #define FAN_EVENT_INFO_TYPE_FID 1 #define FAN_EVENT_INFO_TYPE_DFID_NAME 2 #define FAN_EVENT_INFO_TYPE_DFID 3 +#define FAN_EVENT_INFO_TYPE_ERROR 4 /* Variable length info record following event metadata */ struct fanotify_event_info_header { @@ -149,6 +150,15 @@ struct fanotify_event_info_fid { unsigned char handle[0]; }; +#define FANOTIFY_EVENT_INFO_ERROR_VERS_1 1 + +struct fanotify_event_info_error { + struct fanotify_event_info_header hdr; + int version; + int error; + __kernel_fsid_t fsid; +}; + struct fanotify_response { __s32 fd; __u32 response;