aboutsummaryrefslogtreecommitdiff
path: root/fs/notify
diff options
context:
space:
mode:
Diffstat (limited to 'fs/notify')
-rw-r--r--fs/notify/fanotify/fanotify.c7
-rw-r--r--fs/notify/fsnotify.c84
2 files changed, 54 insertions, 37 deletions
diff --git a/fs/notify/fanotify/fanotify.c b/fs/notify/fanotify/fanotify.c
index 9167884a61ec..1192c9953620 100644
--- a/fs/notify/fanotify/fanotify.c
+++ b/fs/notify/fanotify/fanotify.c
@@ -268,12 +268,11 @@ static u32 fanotify_group_event_mask(struct fsnotify_group *group,
continue;
/*
- * If the event is for a child and this mark is on a parent not
+ * If the event is on a child and this mark is on a parent not
* watching children, don't send it!
*/
- if (event_mask & FS_EVENT_ON_CHILD &&
- type == FSNOTIFY_OBJ_TYPE_INODE &&
- !(mark->mask & FS_EVENT_ON_CHILD))
+ if (type == FSNOTIFY_OBJ_TYPE_PARENT &&
+ !(mark->mask & FS_EVENT_ON_CHILD))
continue;
marks_mask |= mark->mask;
diff --git a/fs/notify/fsnotify.c b/fs/notify/fsnotify.c
index c5c68bcbaadf..30d422b8c0fc 100644
--- a/fs/notify/fsnotify.c
+++ b/fs/notify/fsnotify.c
@@ -152,6 +152,13 @@ static bool fsnotify_event_needs_parent(struct inode *inode, struct mount *mnt,
if (mask & FS_ISDIR)
return false;
+ /*
+ * All events that are possible on child can also may be reported with
+ * parent/name info to inode/sb/mount. Otherwise, a watching parent
+ * could result in events reported with unexpected name info to sb/mount.
+ */
+ BUILD_BUG_ON(FS_EVENTS_POSS_ON_CHILD & ~FS_EVENTS_POSS_TO_PARENT);
+
/* Did either inode/sb/mount subscribe for events with parent/name? */
marks_mask |= fsnotify_parent_needed_mask(inode->i_fsnotify_mask);
marks_mask |= fsnotify_parent_needed_mask(inode->i_sb->s_fsnotify_mask);
@@ -249,6 +256,10 @@ static int fsnotify_handle_inode_event(struct fsnotify_group *group,
path && d_unlinked(path->dentry))
return 0;
+ /* Check interest of this mark in case event was sent with two marks */
+ if (!(mask & inode_mark->mask & ALL_FSNOTIFY_EVENTS))
+ return 0;
+
return ops->handle_inode_event(inode_mark, mask, inode, dir, name, cookie);
}
@@ -258,38 +269,46 @@ static int fsnotify_handle_event(struct fsnotify_group *group, __u32 mask,
u32 cookie, struct fsnotify_iter_info *iter_info)
{
struct fsnotify_mark *inode_mark = fsnotify_iter_inode_mark(iter_info);
- struct fsnotify_mark *child_mark = fsnotify_iter_child_mark(iter_info);
+ struct fsnotify_mark *parent_mark = fsnotify_iter_parent_mark(iter_info);
int ret;
if (WARN_ON_ONCE(fsnotify_iter_sb_mark(iter_info)) ||
WARN_ON_ONCE(fsnotify_iter_vfsmount_mark(iter_info)))
return 0;
- /*
- * An event can be sent on child mark iterator instead of inode mark
- * iterator because of other groups that have interest of this inode
- * and have marks on both parent and child. We can simplify this case.
- */
- if (!inode_mark) {
- inode_mark = child_mark;
- child_mark = NULL;
+ if (parent_mark) {
+ /*
+ * parent_mark indicates that the parent inode is watching
+ * children and interested in this event, which is an event
+ * possible on child. But is *this mark* watching children and
+ * interested in this event?
+ */
+ if (parent_mark->mask & FS_EVENT_ON_CHILD) {
+ ret = fsnotify_handle_inode_event(group, parent_mark, mask,
+ data, data_type, dir, name, 0);
+ if (ret)
+ return ret;
+ }
+ if (!inode_mark)
+ return 0;
+ }
+
+ if (mask & FS_EVENT_ON_CHILD) {
+ /*
+ * Some events can be sent on both parent dir and child marks
+ * (e.g. FS_ATTRIB). If both parent dir and child are
+ * watching, report the event once to parent dir with name (if
+ * interested) and once to child without name (if interested).
+ * The child watcher is expecting an event without a file name
+ * and without the FS_EVENT_ON_CHILD flag.
+ */
+ mask &= ~FS_EVENT_ON_CHILD;
dir = NULL;
name = NULL;
}
- ret = fsnotify_handle_inode_event(group, inode_mark, mask, data, data_type,
- dir, name, cookie);
- if (ret || !child_mark)
- return ret;
-
- /*
- * Some events can be sent on both parent dir and child marks
- * (e.g. FS_ATTRIB). If both parent dir and child are watching,
- * report the event once to parent dir with name and once to child
- * without name.
- */
- return fsnotify_handle_inode_event(group, child_mark, mask, data, data_type,
- NULL, NULL, 0);
+ return fsnotify_handle_inode_event(group, inode_mark, mask, data, data_type,
+ dir, name, cookie);
}
static int send_to_group(__u32 mask, const void *data, int data_type,
@@ -447,7 +466,7 @@ int fsnotify(__u32 mask, const void *data, int data_type, struct inode *dir,
struct fsnotify_iter_info iter_info = {};
struct super_block *sb;
struct mount *mnt = NULL;
- struct inode *child = NULL;
+ struct inode *parent = NULL;
int ret = 0;
__u32 test_mask, marks_mask;
@@ -459,11 +478,10 @@ int fsnotify(__u32 mask, const void *data, int data_type, struct inode *dir,
inode = dir;
} else if (mask & FS_EVENT_ON_CHILD) {
/*
- * Event on child - report on TYPE_INODE to dir if it is
- * watching children and on TYPE_CHILD to child.
+ * Event on child - report on TYPE_PARENT to dir if it is
+ * watching children and on TYPE_INODE to child.
*/
- child = inode;
- inode = dir;
+ parent = dir;
}
sb = inode->i_sb;
@@ -477,7 +495,7 @@ int fsnotify(__u32 mask, const void *data, int data_type, struct inode *dir,
if (!sb->s_fsnotify_marks &&
(!mnt || !mnt->mnt_fsnotify_marks) &&
(!inode || !inode->i_fsnotify_marks) &&
- (!child || !child->i_fsnotify_marks))
+ (!parent || !parent->i_fsnotify_marks))
return 0;
marks_mask = sb->s_fsnotify_mask;
@@ -485,8 +503,8 @@ int fsnotify(__u32 mask, const void *data, int data_type, struct inode *dir,
marks_mask |= mnt->mnt_fsnotify_mask;
if (inode)
marks_mask |= inode->i_fsnotify_mask;
- if (child)
- marks_mask |= child->i_fsnotify_mask;
+ if (parent)
+ marks_mask |= parent->i_fsnotify_mask;
/*
@@ -509,9 +527,9 @@ int fsnotify(__u32 mask, const void *data, int data_type, struct inode *dir,
iter_info.marks[FSNOTIFY_OBJ_TYPE_INODE] =
fsnotify_first_mark(&inode->i_fsnotify_marks);
}
- if (child) {
- iter_info.marks[FSNOTIFY_OBJ_TYPE_CHILD] =
- fsnotify_first_mark(&child->i_fsnotify_marks);
+ if (parent) {
+ iter_info.marks[FSNOTIFY_OBJ_TYPE_PARENT] =
+ fsnotify_first_mark(&parent->i_fsnotify_marks);
}
/*