diff options
| -rw-r--r-- | fs/notify/fanotify/fanotify_user.c | 25 | 
1 files changed, 17 insertions, 8 deletions
diff --git a/fs/notify/fanotify/fanotify_user.c b/fs/notify/fanotify/fanotify_user.c index f69c451018e3..62fe0b679e58 100644 --- a/fs/notify/fanotify/fanotify_user.c +++ b/fs/notify/fanotify/fanotify_user.c @@ -1585,16 +1585,25 @@ static int fanotify_test_fsid(struct dentry *dentry, __kernel_fsid_t *fsid)  }  /* Check if filesystem can encode a unique fid */ -static int fanotify_test_fid(struct dentry *dentry) +static int fanotify_test_fid(struct dentry *dentry, unsigned int flags)  { +	unsigned int mark_type = flags & FANOTIFY_MARK_TYPE_BITS; +	const struct export_operations *nop = dentry->d_sb->s_export_op; + +	/* +	 * We need to make sure that the filesystem supports encoding of +	 * file handles so user can use name_to_handle_at() to compare fids +	 * reported with events to the file handle of watched objects. +	 */ +	if (!nop) +		return -EOPNOTSUPP; +  	/* -	 * We need to make sure that the file system supports at least -	 * encoding a file handle so user can use name_to_handle_at() to -	 * compare fid returned with event to the file handle of watched -	 * objects. However, even the relaxed AT_HANDLE_FID flag requires -	 * at least empty export_operations for ecoding unique file ids. +	 * For sb/mount mark, we also need to make sure that the filesystem +	 * supports decoding file handles, so user has a way to map back the +	 * reported fids to filesystem objects.  	 */ -	if (!dentry->d_sb->s_export_op) +	if (mark_type != FAN_MARK_INODE && !nop->fh_to_dentry)  		return -EOPNOTSUPP;  	return 0; @@ -1812,7 +1821,7 @@ static int do_fanotify_mark(int fanotify_fd, unsigned int flags, __u64 mask,  		if (ret)  			goto path_put_and_out; -		ret = fanotify_test_fid(path.dentry); +		ret = fanotify_test_fid(path.dentry, flags);  		if (ret)  			goto path_put_and_out;  | 
