[PATCH 4.14 059/218] inotify: show inotify mask flags in proc fdinfo

Greg Kroah-Hartman
2022-06-13T10:46:01Z

From: Amir Goldstein <amir73il@gmail.com>

[ Upstream commit a32e697cda27679a0327ae2cafdad8c7170f548f ]

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 <amir73il@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
fs/notify/fdinfo.c | 11 ++---------
fs/notify/inotify/inotify.h | 12 ++++++++++++
fs/notify/inotify/inotify_user.c | 2 +-
3 files changed, 15 insertions(+), 10 deletions(-)

diff --git a/fs/notify/fdinfo.c b/fs/notify/fdinfo.c
index 517f88c1dbe5..c62a87ee3b00 100644
--- a/fs/notify/fdinfo.c
+++ b/fs/notify/fdinfo.c
@@ -83,16 +83,9 @@ static void inotify_fdinfo(struct seq_file *m, struct fsnotify_mark *mark)
inode_mark = container_of(mark, struct inotify_inode_mark, fsn_mark);
inode = igrab(mark->connector->inode);
if (inode) {
- /*
- * IN_ALL_EVENTS represents all of the mask bits
- * that we expose to userspace. There is at
- * least one bit (FS_EVENT_ON_CHILD) which is
- * used only internally to the kernel.
- */
- u32 mask = mark->mask & IN_ALL_EVENTS;
- seq_printf(m, "inotify wd:%x ino:%lx sdev:%x mask:%x ignored_mask:%x ",
+ seq_printf(m, "inotify wd:%x ino:%lx sdev:%x mask:%x ignored_mask:0 ",
inode_mark->wd, inode->i_ino, inode->i_sb->s_dev,
- mask, mark->ignored_mask);
+ inotify_mark_user_mask(mark));
show_mark_fhandle(m, inode);
seq_putc(m, '\n');
iput(inode);
diff --git a/fs/notify/inotify/inotify.h b/fs/notify/inotify/inotify.h
index c00d2caca894..63050e25c84d 100644
--- a/fs/notify/inotify/inotify.h
+++ b/fs/notify/inotify/inotify.h
@@ -21,6 +21,18 @@ static inline struct inotify_event_info *INOTIFY_E(struct fsnotify_event *fse)
return container_of(fse, struct inotify_event_info, fse);
}

+/*
+ * INOTIFY_USER_FLAGS represents all of the mask bits that we expose to
+ * userspace. There is at least one bit (FS_EVENT_ON_CHILD) which is
+ * used only internally to the kernel.
+ */
+#define INOTIFY_USER_MASK (IN_ALL_EVENTS | IN_ONESHOT | IN_EXCL_UNLINK)
+
+static inline __u32 inotify_mark_user_mask(struct fsnotify_mark *fsn_mark)
+{
+ return fsn_mark->mask & INOTIFY_USER_MASK;
+}
+
extern void inotify_ignored_and_remove_idr(struct fsnotify_mark *fsn_mark,
struct fsnotify_group *group);
extern int inotify_handle_event(struct fsnotify_group *group,
diff --git a/fs/notify/inotify/inotify_user.c b/fs/notify/inotify/inotify_user.c
index 7cc7d3fb1862..2393956542bc 100644
--- a/fs/notify/inotify/inotify_user.c
+++ b/fs/notify/inotify/inotify_user.c
@@ -95,7 +95,7 @@ static inline __u32 inotify_arg_to_mask(u32 arg)
mask = (FS_IN_IGNORED | FS_EVENT_ON_CHILD | FS_UNMOUNT);

/* mask off the flags used to open the fd */
- mask |= (arg & (IN_ALL_EVENTS | IN_ONESHOT | IN_EXCL_UNLINK));
+ mask |= (arg & INOTIFY_USER_MASK);

return mask;
}
--
2.35.1