A potential bug in inotify_user.c
Following comment is at fs/inotify_user.c:287
/* coalescing: drop this event if it is a dupe of the previous */
I think the previous event in the comment should be the last event in the
link list. But inotify_dev_get_event return the first event in the list.
In addition, it doesn't check whether the list is empty
Signed-off-by: Yan Zheng<yanzheng@21cn.com>
Acked-by: Robert Love <rlove@rlove.org>
Cc: John McCutchan <ttb@tentacle.dhs.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/fs/inotify_user.c b/fs/inotify_user.c
index 5e00933..c509a81 100644
--- a/fs/inotify_user.c
+++ b/fs/inotify_user.c
@@ -248,6 +248,19 @@
}
/*
+ * inotify_dev_get_last_event - return the last event in the given dev's queue
+ *
+ * Caller must hold dev->ev_mutex.
+ */
+static inline struct inotify_kernel_event *
+inotify_dev_get_last_event(struct inotify_device *dev)
+{
+ if (list_empty(&dev->events))
+ return NULL;
+ return list_entry(dev->events.prev, struct inotify_kernel_event, list);
+}
+
+/*
* inotify_dev_queue_event - event handler registered with core inotify, adds
* a new event to the given device
*
@@ -273,7 +286,7 @@
put_inotify_watch(w); /* final put */
/* coalescing: drop this event if it is a dupe of the previous */
- last = inotify_dev_get_event(dev);
+ last = inotify_dev_get_last_event(dev);
if (last && last->event.mask == mask && last->event.wd == wd &&
last->event.cookie == cookie) {
const char *lastname = last->name;