Merge tag 'fsnotify_for_v5.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs

Pull fsnotify updates from Jan Kara:
 "Several smaller fixes and cleanups for fsnotify subsystem"

* tag 'fsnotify_for_v5.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs:
  fanotify: fix ignore mask logic for events on child and on dir
  fanotify: don't write with size under sizeof(response)
  fsnotify: Remove proc_fs.h include
  fanotify: remove reference to fill_event_metadata()
  fsnotify: add mutex destroy
  fanotify: prefix should_merge()
  fanotify: Replace zero-length array with flexible-array
  inotify: Fix error return code assignment flow.
  fsnotify: Add missing annotation for fsnotify_finish_user_wait() and for fsnotify_prepare_user_wait()

Author: torvalds

fs/notify/fanotify/fanotify.c

@@ -70,7 +70,7 @@ static bool fanotify_name_event_equal(struct fanotify_name_event *fne1,
 	return !memcmp(fne1->name, fne2->name, fne1->name_len);
 }
 
-static bool should_merge(struct fsnotify_event *old_fsn,
+static bool fanotify_should_merge(struct fsnotify_event *old_fsn,
 			 struct fsnotify_event *new_fsn)
 {
 	struct fanotify_event *old, *new;
@@ -129,7 +129,7 @@ static int fanotify_merge(struct list_head *list, struct fsnotify_event *event)
 		return 0;
 
 	list_for_each_entry_reverse(test_event, list, list) {
-		if (should_merge(test_event, event)) {
+		if (fanotify_should_merge(test_event, event)) {
 			FANOTIFY_E(test_event)->mask |= new->mask;
 			return 1;
 		}
@@ -232,6 +232,10 @@ static u32 fanotify_group_event_mask(struct fsnotify_group *group,
 		if (!fsnotify_iter_should_report_type(iter_info, type))
 			continue;
 		mark = iter_info->marks[type];
+
+		/* Apply ignore mask regardless of ISDIR and ON_CHILD flags */
+		marks_ignored_mask |= mark->ignored_mask;
+
 		/*
 		 * If the event is on dir and this mark doesn't care about
 		 * events on dir, don't send it!
@@ -249,7 +253,6 @@ static u32 fanotify_group_event_mask(struct fsnotify_group *group,
 			continue;
 
 		marks_mask |= mark->mask;
-		marks_ignored_mask |= mark->ignored_mask;
 	}
 
 	test_mask = event_mask & marks_mask & ~marks_ignored_mask;

fs/notify/fanotify/fanotify.h

@@ -89,7 +89,7 @@ struct fanotify_name_event {
 	__kernel_fsid_t fsid;
 	struct fanotify_fh dir_fh;
 	u8 name_len;
-	char name[0];
+	char name[];
 };
 
 static inline struct fanotify_name_event *

fs/notify/fanotify/fanotify_user.c

@@ -328,7 +328,7 @@ static ssize_t copy_event_to_user(struct fsnotify_group *group,
 	ret = -EFAULT;
 	/*
 	 * Sanity check copy size in case get_one_event() and
-	 * fill_event_metadata() event_len sizes ever get out of sync.
+	 * event_len sizes ever get out of sync.
 	 */
 	if (WARN_ON_ONCE(metadata.event_len > count))
 		goto out_close_fd;
@@ -487,8 +487,10 @@ static ssize_t fanotify_write(struct file *file, const char __user *buf, size_t
 
 	group = file->private_data;
 
-	if (count > sizeof(response))
-		count = sizeof(response);
+	if (count < sizeof(response))
+		return -EINVAL;
+
+	count = sizeof(response);
 
 	pr_debug("%s: group=%p count=%zu\n", __func__, group, count);
 

fs/notify/fdinfo.c

@@ -11,7 +11,6 @@
 #include <linux/sched.h>
 #include <linux/types.h>
 #include <linux/seq_file.h>
-#include <linux/proc_fs.h>
 #include <linux/exportfs.h>
 
 #include "inotify/inotify.h"

fs/notify/group.c

@@ -25,6 +25,7 @@ static void fsnotify_final_destroy_group(struct fsnotify_group *group)
 		group->ops->free_group_priv(group);
 
 	mem_cgroup_put(group->memcg);
+	mutex_destroy(&group->mark_mutex);
 
 	kfree(group);
 }

fs/notify/inotify/inotify_user.c

@@ -764,20 +764,18 @@ SYSCALL_DEFINE2(inotify_rm_watch, int, fd, __s32, wd)
 	struct fsnotify_group *group;
 	struct inotify_inode_mark *i_mark;
 	struct fd f;
-	int ret = 0;
+	int ret = -EINVAL;
 
 	f = fdget(fd);
 	if (unlikely(!f.file))
 		return -EBADF;
 
 	/* verify that this is indeed an inotify instance */
-	ret = -EINVAL;
 	if (unlikely(f.file->f_op != &inotify_fops))
 		goto out;
 
 	group = f.file->private_data;
 
-	ret = -EINVAL;
 	i_mark = inotify_idr_find(group, wd);
 	if (unlikely(!i_mark))
 		goto out;

fs/notify/mark.c

@@ -325,13 +325,16 @@ static void fsnotify_put_mark_wake(struct fsnotify_mark *mark)
 }
 
 bool fsnotify_prepare_user_wait(struct fsnotify_iter_info *iter_info)
+	__releases(&fsnotify_mark_srcu)
 {
 	int type;
 
 	fsnotify_foreach_obj_type(type) {
 		/* This can fail if mark is being removed */
-		if (!fsnotify_get_mark_safe(iter_info->marks[type]))
+		if (!fsnotify_get_mark_safe(iter_info->marks[type])) {
+			__release(&fsnotify_mark_srcu);
 			goto fail;
+		}
 	}
 
 	/*
@@ -350,6 +353,7 @@ bool fsnotify_prepare_user_wait(struct fsnotify_iter_info *iter_info)
 }
 
 void fsnotify_finish_user_wait(struct fsnotify_iter_info *iter_info)
+	__acquires(&fsnotify_mark_srcu)
 {
 	int type;