5.15-stable review patch. If anyone has any objections, please let me know. ------------------ From: Gabriel Krisman Bertazi <krisman@xxxxxxxxxxxxx> [ Upstream commit 130a3c742107acff985541c28360c8b40203559c ] The error info 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. Link: https://lore.kernel.org/r/20211025192746.66445-28-krisman@xxxxxxxxxxxxx Reviewed-by: Amir Goldstein <amir73il@xxxxxxxxx> Reviewed-by: Jan Kara <jack@xxxxxxx> Signed-off-by: Gabriel Krisman Bertazi <krisman@xxxxxxxxxxxxx> Signed-off-by: Jan Kara <jack@xxxxxxx> Signed-off-by: Chuck Lever <chuck.lever@xxxxxxxxxx> --- fs/notify/fanotify/fanotify.c | 1 + fs/notify/fanotify/fanotify.h | 1 + fs/notify/fanotify/fanotify_user.c | 36 ++++++++++++++++++++++++++++++ include/uapi/linux/fanotify.h | 7 ++++++ 4 files changed, 45 insertions(+) diff --git a/fs/notify/fanotify/fanotify.c b/fs/notify/fanotify/fanotify.c index 465f07e70e6dc..af61425e6e3bf 100644 --- a/fs/notify/fanotify/fanotify.c +++ b/fs/notify/fanotify/fanotify.c @@ -621,6 +621,7 @@ static struct fanotify_event *fanotify_alloc_error_event( return NULL; fee->fae.type = FANOTIFY_EVENT_TYPE_FS_ERROR; + fee->error = report->error; fee->err_count = 1; fee->fsid = *fsid; diff --git a/fs/notify/fanotify/fanotify.h b/fs/notify/fanotify/fanotify.h index edd7587adcc59..d25f500bf7e79 100644 --- a/fs/notify/fanotify/fanotify.h +++ b/fs/notify/fanotify/fanotify.h @@ -205,6 +205,7 @@ FANOTIFY_NE(struct fanotify_event *event) struct fanotify_error_event { struct fanotify_event fae; + s32 error; /* Error reported by the Filesystem. */ u32 err_count; /* Suppressed errors count */ __kernel_fsid_t fsid; /* FSID this error refers to. */ diff --git a/fs/notify/fanotify/fanotify_user.c b/fs/notify/fanotify/fanotify_user.c index fa3dac9c59f69..133d9b5ffdb10 100644 --- a/fs/notify/fanotify/fanotify_user.c +++ b/fs/notify/fanotify/fanotify_user.c @@ -115,6 +115,8 @@ struct kmem_cache *fanotify_perm_event_cachep __read_mostly; (sizeof(struct fanotify_event_info_fid) + sizeof(struct file_handle)) #define FANOTIFY_PIDFD_INFO_HDR_LEN \ sizeof(struct fanotify_event_info_pidfd) +#define FANOTIFY_ERROR_INFO_LEN \ + (sizeof(struct fanotify_event_info_error)) static int fanotify_fid_info_len(int fh_len, int name_len) { @@ -139,6 +141,9 @@ static size_t fanotify_event_len(unsigned int info_mode, if (!info_mode) return event_len; + if (fanotify_is_error_event(event->mask)) + event_len += FANOTIFY_ERROR_INFO_LEN; + info = fanotify_event_info(event); if (fanotify_event_has_dir_fh(event)) { @@ -324,6 +329,28 @@ 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_ERROR_INFO_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_fid_info_to_user(__kernel_fsid_t *fsid, struct fanotify_fh *fh, int info_type, const char *name, size_t name_len, @@ -530,6 +557,15 @@ static int copy_info_records_to_user(struct fanotify_event *event, total_bytes += ret; } + if (fanotify_is_error_event(event->mask)) { + ret = copy_error_info_to_user(event, buf, count); + if (ret < 0) + return ret; + buf += ret; + count -= ret; + total_bytes += ret; + } + return total_bytes; } diff --git a/include/uapi/linux/fanotify.h b/include/uapi/linux/fanotify.h index 2990731ddc8bc..bd1932c2074d5 100644 --- a/include/uapi/linux/fanotify.h +++ b/include/uapi/linux/fanotify.h @@ -126,6 +126,7 @@ struct fanotify_event_metadata { #define FAN_EVENT_INFO_TYPE_DFID_NAME 2 #define FAN_EVENT_INFO_TYPE_DFID 3 #define FAN_EVENT_INFO_TYPE_PIDFD 4 +#define FAN_EVENT_INFO_TYPE_ERROR 5 /* Variable length info record following event metadata */ struct fanotify_event_info_header { @@ -160,6 +161,12 @@ struct fanotify_event_info_pidfd { __s32 pidfd; }; +struct fanotify_event_info_error { + struct fanotify_event_info_header hdr; + __s32 error; + __u32 error_count; +}; + struct fanotify_response { __s32 fd; __u32 response; -- 2.43.0
