Commit e3ba7307 authored by Jan Kara's avatar Jan Kara Committed by Paul Moore
Browse files

fsnotify: Remove fsnotify_duplicate_mark() 



There are only two calls sites of fsnotify_duplicate_mark(). Those are
in kernel/audit_tree.c and both are bogus. Vfsmount pointer is unused
for audit tree, inode pointer and group gets set in
fsnotify_add_mark_locked() later anyway, mask and free_mark are already
set in alloc_chunk(). In fact, calling fsnotify_duplicate_mark() is
actively harmful because following fsnotify_add_mark_locked() will leak
group reference by overwriting the group pointer. So just remove the two
calls to fsnotify_duplicate_mark() and the function.

Signed-off-by: default avatarJan Kara <jack@suse.cz>
[PM: line wrapping to fit in 80 chars]
Signed-off-by: default avatarPaul Moore <paul@paul-moore.com>
parent 533c7b69

fs/notify/mark.c

+0 −12
Original line number Diff line number Diff line
@@ -510,18 +510,6 @@ void fsnotify_detach_group_marks(struct fsnotify_group *group) 
	}

}



void fsnotify_duplicate_mark(struct fsnotify_mark *new, struct fsnotify_mark *old)

{

	assert_spin_locked(&old->lock);

	new->inode = old->inode;

	new->mnt = old->mnt;

	if (old->group)

		fsnotify_get_group(old->group);

	new->group = old->group;

	new->mask = old->mask;

	new->free_mark = old->free_mark;

}



/*

 * Nothing fancy, just initialize lists and locks and counters.

 */

include/linux/fsnotify_backend.h

+0 −2
Original line number Diff line number Diff line
@@ -324,8 +324,6 @@ extern void fsnotify_init_mark(struct fsnotify_mark *mark, void (*free_mark)(str 
extern struct fsnotify_mark *fsnotify_find_inode_mark(struct fsnotify_group *group, struct inode *inode);

/* find (and take a reference) to a mark associated with group and vfsmount */

extern struct fsnotify_mark *fsnotify_find_vfsmount_mark(struct fsnotify_group *group, struct vfsmount *mnt);

/* copy the values from old into new */

extern void fsnotify_duplicate_mark(struct fsnotify_mark *new, struct fsnotify_mark *old);

/* set the ignored_mask of a mark */

extern void fsnotify_set_mark_ignored_mask_locked(struct fsnotify_mark *mark, __u32 mask);

/* set the mask of a mark (might pin the object into memory */

kernel/audit_tree.c

+4 −4
Original line number Diff line number Diff line
@@ -258,8 +258,8 @@ static void untag_chunk(struct node *p) 
	if (!new)

		goto Fallback;



	fsnotify_duplicate_mark(&new->mark, entry);

	if (fsnotify_add_mark(&new->mark, new->mark.group, new->mark.inode, NULL, 1)) {

	if (fsnotify_add_mark(&new->mark,

			      entry->group, entry->inode, NULL, 1)) {

		fsnotify_put_mark(&new->mark);

		goto Fallback;

	}
@@ -395,8 +395,8 @@ static int tag_chunk(struct inode *inode, struct audit_tree *tree) 
		return -ENOENT;

	}



	fsnotify_duplicate_mark(chunk_entry, old_entry);

	if (fsnotify_add_mark(chunk_entry, chunk_entry->group, chunk_entry->inode, NULL, 1)) {

	if (fsnotify_add_mark(chunk_entry,

			      old_entry->group, old_entry->inode, NULL, 1)) {

		spin_unlock(&old_entry->lock);

		fsnotify_put_mark(chunk_entry);

		fsnotify_put_mark(old_entry);

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