On Thu 16-07-20 11:42:29, Amir Goldstein wrote:
> For a group with fanotify_init() flag FAN_REPORT_DFID_NAME, the parent
> fid and name are reported for events on non-directory objects with an
> info record of type FAN_EVENT_INFO_TYPE_DFID_NAME.
>
> If the group also has the init flag FAN_REPORT_FID, the child fid
> is also reported with another info record that follows the first info
> record. The second info record is the same info record that would have
> been reported to a group with only FAN_REPORT_FID flag.
>
> When the child fid needs to be recorded, the variable size struct
> fanotify_name_event is preallocated with enough space to store the
> child fh between the dir fh and the name.
>
> Signed-off-by: Amir Goldstein <amir73il@xxxxxxxxx>
> ---
> fs/notify/fanotify/fanotify.c | 30 ++++++++++++++++++++++++++----
> fs/notify/fanotify/fanotify.h | 8 +++++++-
> fs/notify/fanotify/fanotify_user.c | 3 ++-
> 3 files changed, 35 insertions(+), 6 deletions(-)
>
> diff --git a/fs/notify/fanotify/fanotify.c b/fs/notify/fanotify/fanotify.c
> index c77b37eb33a9..1d8eb886fe08 100644
> --- a/fs/notify/fanotify/fanotify.c
> +++ b/fs/notify/fanotify/fanotify.c
> @@ -479,15 +479,22 @@ static struct fanotify_event *fanotify_alloc_fid_event(struct inode *id,
> static struct fanotify_event *fanotify_alloc_name_event(struct inode *id,
> __kernel_fsid_t *fsid,
> const struct qstr *file_name,
> + struct inode *child,
> gfp_t gfp)
> {
> struct fanotify_name_event *fne;
> struct fanotify_info *info;
> - struct fanotify_fh *dfh;
> + struct fanotify_fh *dfh, *ffh;
> unsigned int dir_fh_len = fanotify_encode_fh_len(id);
> + unsigned int child_fh_len = fanotify_encode_fh_len(child);
> unsigned int size;
>
> + if (WARN_ON_ONCE(dir_fh_len % FANOTIFY_FH_HDR_LEN))
> + child_fh_len = 0;
> +
Why this check? Do you want to check everything is 4-byte aligned? But then
FANOTIFY_FH_HDR_LEN works mostly by accident...
Honza
--
Jan Kara <jack@xxxxxxxx>
SUSE Labs, CR
