From patchwork Wed Aug 4 16:06:09 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: 12419377 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=-16.7 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,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 B41A6C432BE for ; Wed, 4 Aug 2021 16:07:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A116660F35 for ; Wed, 4 Aug 2021 16:07:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233604AbhHDQIJ (ORCPT ); Wed, 4 Aug 2021 12:08:09 -0400 Received: from bhuna.collabora.co.uk ([46.235.227.227]:42152 "EHLO bhuna.collabora.co.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231474AbhHDQII (ORCPT ); Wed, 4 Aug 2021 12:08:08 -0400 Received: from [127.0.0.1] (localhost [127.0.0.1]) (Authenticated sender: krisman) with ESMTPSA id 8B1F71F43697 From: Gabriel Krisman Bertazi To: jack@suse.com, amir73il@gmail.com Cc: djwong@kernel.org, tytso@mit.edu, david@fromorbit.com, dhowells@redhat.com, khazhy@google.com, linux-fsdevel@vger.kernel.org, linux-ext4@vger.kernel.org, linux-api@vger.kernel.org, Gabriel Krisman Bertazi , kernel@collabora.com Subject: [PATCH v5 20/23] fanotify: Emit generic error info type for error event Date: Wed, 4 Aug 2021 12:06:09 -0400 Message-Id: <20210804160612.3575505-21-krisman@collabora.com> X-Mailer: git-send-email 2.32.0 In-Reply-To: <20210804160612.3575505-1-krisman@collabora.com> References: <20210804160612.3575505-1-krisman@collabora.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org The Error info type is a record sent to users on FAN_FS_ERROR events documenting the type of error. It also carries an error count, documenting how many errors were observed since the last reporting. Signed-off-by: Gabriel Krisman Bertazi --- fs/notify/fanotify/fanotify_user.c | 35 ++++++++++++++++++++++++++++++ include/uapi/linux/fanotify.h | 7 ++++++ 2 files changed, 42 insertions(+) diff --git a/fs/notify/fanotify/fanotify_user.c b/fs/notify/fanotify/fanotify_user.c index 74def82630bb..ea22586c39e6 100644 --- a/fs/notify/fanotify/fanotify_user.c +++ b/fs/notify/fanotify/fanotify_user.c @@ -107,6 +107,8 @@ struct kmem_cache *fanotify_perm_event_cachep __read_mostly; #define FANOTIFY_EVENT_ALIGN 4 #define FANOTIFY_INFO_HDR_LEN \ (sizeof(struct fanotify_event_info_fid) + sizeof(struct file_handle)) +#define FANOTIFY_INFO_ERROR_LEN \ + (sizeof(struct fanotify_event_info_error)) static int fanotify_fid_info_len(int fh_len, int name_len) { @@ -130,6 +132,9 @@ static size_t fanotify_event_len(struct fanotify_event *event, if (!fid_mode) return event_len; + if (fanotify_is_error_event(event->mask)) + event_len += FANOTIFY_INFO_ERROR_LEN; + info = fanotify_event_info(event); dir_fh_len = fanotify_event_dir_fh_len(event); fh_len = fanotify_event_object_fh_len(event); @@ -395,6 +400,28 @@ static int process_access_response(struct fsnotify_group *group, return -ENOENT; } +static size_t copy_error_info_to_user(struct fanotify_event *event, + char __user *buf, int count) +{ + struct fanotify_event_info_error info; + struct fanotify_error_event *fee = FANOTIFY_EE(event); + + info.hdr.info_type = FAN_EVENT_INFO_TYPE_ERROR; + info.hdr.pad = 0; + info.hdr.len = FANOTIFY_INFO_ERROR_LEN; + + if (WARN_ON(count < info.hdr.len)) + return -EFAULT; + + info.error = fee->error; + info.error_count = fee->err_count; + + 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) @@ -553,6 +580,14 @@ static ssize_t copy_event_to_user(struct fsnotify_group *group, if (f) fd_install(fd, f); + if (fanotify_is_error_event(event->mask)) { + ret = copy_error_info_to_user(event, buf, count); + if (ret < 0) + goto out_close_fd; + buf += ret; + count -= ret; + } + /* Event info records order is: dir fid + name, child fid */ if (fanotify_event_dir_fh_len(event)) { info_type = info->name_len ? FAN_EVENT_INFO_TYPE_DFID_NAME : diff --git a/include/uapi/linux/fanotify.h b/include/uapi/linux/fanotify.h index 16402037fc7a..80040a92e9d9 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 +150,12 @@ struct fanotify_event_info_fid { unsigned char handle[0]; }; +struct fanotify_event_info_error { + struct fanotify_event_info_header hdr; + __s32 error; + __u32 error_count; +}; + struct fanotify_response { __s32 fd; __u32 response;