Keith Mok <[EMAIL PROTECTED]> writes:

> Patch modified according to coding style in Linux.
> NLS and UTF8 filename length are checked and limited to 255 after convert to 
> unicode in xlate_to_uni function.
>
>
> Signed-off-by: Keith Mok <[EMAIL PROTECTED]>

Looks good to me. I'll submit after some test. (and maybe some cleanup
of this area).

Thanks.

> --- linux-source-2.6.22/fs/fat/dir.c.orig     2007-07-09 07:32:17.000000000 
> +0800
> +++ linux-source-2.6.22/fs/fat/dir.c  2008-02-15 17:24:18.000000000 +0800
> @@ -124,7 +124,7 @@ static inline int fat_get_entry(struct i
>   * but ignore that right now.
>   * Ahem... Stack smashing in ring 0 isn't fun. Fixed.
>   */
> -static int uni16_to_x8(unsigned char *ascii, wchar_t *uni, int uni_xlate,
> +static int uni16_to_x8(unsigned char *ascii, wchar_t *uni, int len, int 
> uni_xlate,
>                      struct nls_table *nls)
>  {
>       wchar_t *ip, ec;
> @@ -135,10 +135,11 @@ static int uni16_to_x8(unsigned char *as
>       ip = uni;
>       op = ascii;
>  
> -     while (*ip) {
> +     while (*ip && ((len - NLS_MAX_CHARSET_SIZE) > 0)) {
>               ec = *ip++;
>               if ( (charlen = nls->uni2char(ec, op, NLS_MAX_CHARSET_SIZE)) > 
> 0) {
>                       op += charlen;
> +                     len -= charlen;
>               } else {
>                       if (uni_xlate == 1) {
>                               *op = ':';
> @@ -149,15 +150,18 @@ static int uni16_to_x8(unsigned char *as
>                                       ec >>= 4;
>                               }
>                               op += 5;
> +                             len -= 5;
>                       } else {
>                               *op++ = '?';
> +                             len--;
>                       }
>               }
> -             /* We have some slack there, so it's OK */
> -             if (op>ascii+256) {
> -                     op = ascii + 256;
> -                     break;
> -             }
> +     }
> +     
> +     if(unlikely(*ip)) {
> +             printk(KERN_WARNING
> +                     "FAT: truncated while convert unicode characters in 
> %s\n",
> +                     __FUNCTION__);
>       }
>       *op = 0;
>       return (op - ascii);
> @@ -311,9 +315,11 @@ int fat_search_long(struct inode *inode,
>       struct nls_table *nls_io = sbi->nls_io;
>       struct nls_table *nls_disk = sbi->nls_disk;
>       wchar_t bufuname[14];
> -     unsigned char xlate_len, nr_slots;
> +     int xlate_len;
> +     unsigned char nr_slots;
>       wchar_t *unicode = NULL;
> -     unsigned char work[8], bufname[260];    /* 256 + 4 */
> +     unsigned char work[8];
> +     unsigned char *bufname = NULL;
>       int uni_xlate = sbi->options.unicode_xlate;
>       int utf8 = sbi->options.utf8;
>       int anycase = (sbi->options.name_check != 's');
> @@ -321,6 +327,10 @@ int fat_search_long(struct inode *inode,
>       loff_t cpos = 0;
>       int chl, i, j, last_u, err;
>  
> +     bufname = (unsigned char*)__get_free_page(GFP_KERNEL);
> +     if (!bufname) {
> +             return -ENOMEM;
> +     }
>       err = -ENOENT;
>       while(1) {
>               if (fat_get_entry(inode, &cpos, &bh, &de) == -1)
> @@ -383,8 +393,8 @@ parse_record:
>  
>               bufuname[last_u] = 0x0000;
>               xlate_len = utf8
> -                     ?utf8_wcstombs(bufname, bufuname, sizeof(bufname))
> -                     :uni16_to_x8(bufname, bufuname, uni_xlate, nls_io);
> +                     ?utf8_wcstombs(bufname, bufuname, PAGE_SIZE)
> +                     :uni16_to_x8(bufname, bufuname, PAGE_SIZE, uni_xlate, 
> nls_io);
>               if (xlate_len == name_len)
>                       if ((!anycase && !memcmp(name, bufname, xlate_len)) ||
>                           (anycase && !nls_strnicmp(nls_io, name, bufname,
> @@ -393,8 +403,8 @@ parse_record:
>  
>               if (nr_slots) {
>                       xlate_len = utf8
> -                             ?utf8_wcstombs(bufname, unicode, 
> sizeof(bufname))
> -                             :uni16_to_x8(bufname, unicode, uni_xlate, 
> nls_io);
> +                             ?utf8_wcstombs(bufname, unicode, PAGE_SIZE)
> +                             :uni16_to_x8(bufname, unicode, PAGE_SIZE, 
> uni_xlate, nls_io);
>                       if (xlate_len != name_len)
>                               continue;
>                       if ((!anycase && !memcmp(name, bufname, xlate_len)) ||
> @@ -413,6 +423,8 @@ Found:
>       sinfo->i_pos = fat_make_i_pos(sb, sinfo->bh, sinfo->de);
>       err = 0;
>  EODir:
> +     if (bufname)
> +             free_page((unsigned long)bufname);
>       if (unicode)
>               free_page((unsigned long)unicode);
>  
> @@ -593,7 +605,7 @@ parse_record:
>       if (isvfat) {
>               bufuname[j] = 0x0000;
>               i = utf8 ? utf8_wcstombs(bufname, bufuname, sizeof(bufname))
> -                      : uni16_to_x8(bufname, bufuname, uni_xlate, nls_io);
> +                      : uni16_to_x8(bufname, bufuname, sizeof(bufname), 
> uni_xlate, nls_io);
>       }
>  
>       fill_name = bufname;
> @@ -605,7 +617,7 @@ parse_record:
>               int buf_size = PAGE_SIZE - (261 * sizeof(unicode[0]));
>               int long_len = utf8
>                       ? utf8_wcstombs(longname, unicode, buf_size)
> -                     : uni16_to_x8(longname, unicode, uni_xlate, nls_io);
> +                     : uni16_to_x8(longname, unicode, buf_size, uni_xlate, 
> nls_io);
>  
>               if (!both) {
>                       fill_name = longname;
> --- linux-source-2.6.22/fs/vfat/namei.c.orig  2007-07-09 07:32:17.000000000 
> +0800
> +++ linux-source-2.6.22/fs/vfat/namei.c       2008-02-15 18:33:15.000000000 
> +0800
> @@ -176,15 +176,8 @@ static inline int vfat_is_used_badchars(
>       for (i = 0; i < len; i++)
>               if (vfat_bad_char(s[i]))
>                       return -EINVAL;
> -     return 0;
> -}
> -
> -static int vfat_valid_longname(const unsigned char *name, unsigned int len)
> -{
> -     if (name[len - 1] == ' ')
> +     if (s[i - 1] == 0x0020) /* last character cannot be space */
>               return -EINVAL;
> -     if (len >= 256)
> -             return -ENAMETOOLONG;
>       return 0;
>  }
>  
> @@ -485,11 +478,14 @@ xlate_to_uni(const unsigned char *name, 
>                */
>               *outlen -= (name_len - len);
>  
> +             if (*outlen > 255)
> +                     return -ENAMETOOLONG;
> +
>               op = &outname[*outlen * sizeof(wchar_t)];
>       } else {
>               if (nls) {
>                       for (i = 0, ip = name, op = outname, *outlen = 0;
> -                          i < len && *outlen <= 260;
> +                          i < len && *outlen <= 255;
>                            *outlen += 1)
>                       {
>                               if (escape && (*ip == ':')) {
> @@ -525,18 +521,20 @@ xlate_to_uni(const unsigned char *name, 
>                                       op += 2;
>                               }
>                       }
> +                     if (i < len)
> +                             return -ENAMETOOLONG;
>               } else {
>                       for (i = 0, ip = name, op = outname, *outlen = 0;
> -                          i < len && *outlen <= 260;
> +                          i < len && *outlen <= 255;
>                            i++, *outlen += 1)
>                       {
>                               *op++ = *ip++;
>                               *op++ = 0;
>                       }
> +                     if (i < len)
> +                             return -ENAMETOOLONG;
>               }
>       }
> -     if (*outlen > 260)
> -             return -ENAMETOOLONG;
>  
>       *longlen = *outlen;
>       if (*outlen % 13) {
> @@ -574,9 +572,6 @@ static int vfat_build_slots(struct inode
>       loff_t offset;
>  
>       *nr_slots = 0;
> -     err = vfat_valid_longname(name, len);
> -     if (err)
> -             return err;
>  
>       page = __get_free_page(GFP_KERNEL);
>       if (!page)
>
>
>

-- 
OGAWA Hirofumi <[EMAIL PROTECTED]>
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