> The current implementation doesn't care NameLength when extracting the name 
> from Name dir-entries, so
> the name may be incorrect.
> (Without null-termination, Insufficient Name dir-entry, etc) Add a NameLength 
> check when extracting
> the name from Name dir-entries to extract correct name.
> And, change to get the information of file/stream-ext dir-entries via the 
> member variable of
> exfat_entry_set_cache.
> 
> ** This patch depends on:
>   '[PATCH v3] exfat: integrates dir-entry getting and validation'.
> 
> Signed-off-by: Tetsuhiro Kohada <kohada...@gmail.com>
> ---
>  fs/exfat/dir.c | 81 ++++++++++++++++++++++++--------------------------
>  1 file changed, 39 insertions(+), 42 deletions(-)
> 
> diff --git a/fs/exfat/dir.c b/fs/exfat/dir.c index 91cdbede0fd1..545bb73b95e9 
> 100644
> --- a/fs/exfat/dir.c
> +++ b/fs/exfat/dir.c
> @@ -28,16 +28,15 @@ static int exfat_extract_uni_name(struct exfat_dentry *ep,
> 
>  }
> 
> -static void exfat_get_uniname_from_ext_entry(struct super_block *sb,
> -             struct exfat_chain *p_dir, int entry, unsigned short *uniname)
> +static int exfat_get_uniname_from_name_entries(struct exfat_entry_set_cache 
> *es,
> +             struct exfat_uni_name *uniname)
>  {
> -     int i;
> -     struct exfat_entry_set_cache *es;
> +     int n, l, i;
>       struct exfat_dentry *ep;
> 
> -     es = exfat_get_dentry_set(sb, p_dir, entry, ES_ALL_ENTRIES);
> -     if (!es)
> -             return;
> +     uniname->name_len = es->de_stream->name_len;
> +     if (uniname->name_len == 0)
> +             return -EIO;
Can we validate ->name_len and name entry ->type in exfat_get_dentry_set() ?
> 
>       /*
>        * First entry  : file entry
> @@ -45,14 +44,15 @@ static void exfat_get_uniname_from_ext_entry(struct 
> super_block *sb,
>        * Third entry  : first file-name entry
>        * So, the index of first file-name dentry should start from 2.
>        */
> -
> -     i = 2;
> -     while ((ep = exfat_get_validated_dentry(es, i++, TYPE_NAME))) {
> -             exfat_extract_uni_name(ep, uniname);
> -             uniname += EXFAT_FILE_NAME_LEN;
> +     for (l = 0, n = 2; l < uniname->name_len; n++) {
> +             ep = exfat_get_validated_dentry(es, n, TYPE_NAME);
> +             if (!ep)
> +                     return -EIO;
> +             for (i = 0; l < uniname->name_len && i < EXFAT_FILE_NAME_LEN; 
> i++, l++)
> +                     uniname->name[l] = 
> le16_to_cpu(ep->dentry.name.unicode_0_14[i]);
>       }
> -
> -     exfat_free_dentry_set(es, false);
> +     uniname->name[l] = 0;
> +     return 0;
>  }

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