kernel/linux.git/fs/notify/fdinfo.c, branch linux-6.0.y

fanotify: prepare for setting event flags in ignore mask

2022-07-01T12:51:13+00:00

Setting flags FAN_ONDIR FAN_EVENT_ON_CHILD in ignore mask has no effect. The FAN_EVENT_ON_CHILD flag in mask implicitly applies to ignore mask and ignore mask is always implicitly applied to events on directories. Define a mark flag that replaces this legacy behavior with logic of applying the ignore mask according to event flags in ignore mask. Implement the new logic to prepare for supporting an ignore mask that ignores events on children and ignore mask that does not ignore events on directories. To emphasize the change in terminology, also rename ignored_mask mark member to ignore_mask and use accessors to get only the effective ignored events or the ignored events and flags. This change in terminology finally aligns with the "ignore mask" language in man pages and in most of the comments. Link: https://lore.kernel.org/r/20220629144210.2983229-2-amir73il@gmail.com Signed-off-by: Amir Goldstein Signed-off-by: Jan Kara

fanotify: create helper fanotify_mark_user_flags()

2022-04-25T12:43:00+00:00

To translate from fsnotify mark flags to user visible flags. Link: https://lore.kernel.org/r/20220422120327.3459282-13-amir73il@gmail.com Signed-off-by: Amir Goldstein Signed-off-by: Jan Kara

fsnotify: create helpers for group mark_mutex lock

2022-04-25T12:37:22+00:00

Create helpers to take and release the group mark_mutex lock. Define a flag FSNOTIFY_GROUP_NOFS in fsnotify_group that determines if the mark_mutex lock is fs reclaim safe or not. If not safe, the lock helpers take the lock and disable direct fs reclaim. In that case we annotate the mutex with a different lockdep class to express to lockdep that an allocation of mark of an fs reclaim safe group may take the group lock of another "NOFS" group to evict inodes. For now, converted only the callers in common code and no backend defines the NOFS flag. It is intended to be set by fanotify for evictable marks support. Link: https://lore.kernel.org/r/20220422120327.3459282-7-amir73il@gmail.com Suggested-by: Jan Kara Link: https://lore.kernel.org/r/20220321112310.vpr7oxro2xkz5llh@quack3.lan/ Signed-off-by: Amir Goldstein Signed-off-by: Jan Kara

inotify: show inotify mask flags in proc fdinfo

2022-04-25T12:37:03+00:00

The inotify mask flags IN_ONESHOT and IN_EXCL_UNLINK are not "internal to kernel" and should be exposed in procfs fdinfo so CRIU can restore them. Fixes: 6933599697c9 ("inotify: hide internal kernel bits from fdinfo") Link: https://lore.kernel.org/r/20220422120327.3459282-2-amir73il@gmail.com Signed-off-by: Amir Goldstein Signed-off-by: Jan Kara

fanotify: fix permission model of unprivileged group

2021-05-25T10:21:14+00:00

Reporting event->pid should depend on the privileges of the user that initialized the group, not the privileges of the user reading the events. Use an internal group flag FANOTIFY_UNPRIV to record the fact that the group was initialized by an unprivileged user. To be on the safe side, the premissions to setup filesystem and mount marks now require that both the user that initialized the group and the user setting up the mark have CAP_SYS_ADMIN. Link: https://lore.kernel.org/linux-fsdevel/CAOQ4uxiA77_P5vtv7e83g0+9d7B5W9ZTE4GfQEYbWmfT1rA=VA@mail.gmail.com/ Fixes: 7cea2a3c505e ("fanotify: support limited functionality for unprivileged users") Cc: # v5.12+ Link: https://lore.kernel.org/r/20210524135321.2190062-1-amir73il@gmail.com Reviewed-by: Matthew Bobrowski Acked-by: Christian Brauner Signed-off-by: Amir Goldstein Signed-off-by: Jan Kara

fanotify: support limited functionality for unprivileged users

2021-03-16T15:55:05+00:00

Add limited support for unprivileged fanotify groups. An unprivileged users is not allowed to get an open file descriptor in the event nor the process pid of another process. An unprivileged user cannot request permission events, cannot set mount/filesystem marks and cannot request unlimited queue/marks. This enables the limited functionality similar to inotify when watching a set of files and directories for OPEN/ACCESS/MODIFY/CLOSE events, without requiring SYS_CAP_ADMIN privileges. The FAN_REPORT_DFID_NAME init flag, provide a method for an unprivileged listener watching a set of directories (with FAN_EVENT_ON_CHILD) to monitor all changes inside those directories. This typically requires that the listener keeps a map of watched directory fid to dirfd (O_PATH), where fid is obtained with name_to_handle_at() before starting to watch for changes. When getting an event, the reported fid of the parent should be resolved to dirfd and fstatsat(2) with dirfd and name should be used to query the state of the filesystem entry. Link: https://lore.kernel.org/r/20210304112921.3996419-3-amir73il@gmail.com Signed-off-by: Amir Goldstein Signed-off-by: Jan Kara

fsnotify: Remove proc_fs.h include

2020-05-13T15:16:14+00:00

proc_fs.h was already included in fdinfo.h Link: https://lore.kernel.org/r/20200512181906.405927-1-fabf@skynet.be Signed-off-by: Fabian Frederick Reviewed-by: Amir Goldstein Signed-off-by: Jan Kara

fsnotify/fdinfo: exportfs_encode_inode_fh() takes pointer as 4th argument

2019-10-17T08:32:59+00:00

The call to exportfs_encode_inode_fh() takes an pointer as the 4th argument, so replace the integer 0 with the NULL pointer. This fixes the following sparse warning: fs/notify/fdinfo.c:53:87: warning: Using plain integer as NULL pointer Link: https://lore.kernel.org/r/20191016095955.3347-1-ben.dooks@codethink.co.uk Signed-off-by: Ben Dooks Signed-off-by: Jan Kara

fsnotify/fdinfo: include fdinfo.h for inotify_show_fdinfo()

2018-11-15T16:34:27+00:00

inotify_show_fdinfo() is defined in fs/notify/fdinfo.c and declared in fs/notify/fdinfo.h, but the declaration isn't included at the point of the definition. Include the header to enforce that the definition matches the declaration. This addresses a gcc warning when -Wmissing-prototypes is enabled. Signed-off-by: Eric Biggers Signed-off-by: Jan Kara

fanotify: store fanotify_init() flags in group's fanotify_data

2018-09-27T13:29:00+00:00

This averts the need to re-generate flags in fanotify_show_fdinfo() and sets the scene for addition of more upcoming flags without growing new members to the fanotify_data struct. Signed-off-by: Amir Goldstein Signed-off-by: Jan Kara