Commit f22032ba authored by Keith Mok's avatar Keith Mok Committed by Linus Torvalds
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vfat: bug fix for vfat cannot handle filename with 255 



This patch fix the problem that the buffer allocated for convert of unicode to
utf8 in fat/dir.c is too small.

And cannot handle filename with 255 asian characters when mounted with utf8
options.

Also it fix the filename length limitation checking in vfat/namei.c that the
filename length should be checked against the number of converted unicode
characters.

Not the length before NLS/UTF8 converted.

Signed-off-by: default avatarKeith Mok <ek9852@gmail.com>
Signed-off-by: default avatarOGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 061e9746

fs/fat/dir.c

+28 −16
Original line number Diff line number Diff line
@@ -124,8 +124,8 @@ static inline int fat_get_entry(struct inode *dir, loff_t *pos, 
 * 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,

		       struct nls_table *nls)

static int uni16_to_x8(unsigned char *ascii, wchar_t *uni, int len,

		       int uni_xlate, struct nls_table *nls)

{

	wchar_t *ip, ec;

	unsigned char *op, nc;
@@ -135,10 +135,11 @@ static int uni16_to_x8(unsigned char *ascii, wchar_t *uni, int uni_xlate, 
	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 = ':';
@@ -149,16 +150,19 @@ static int uni16_to_x8(unsigned char *ascii, wchar_t *uni, int uni_xlate, 
					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: filename was truncated while "

		       "converting.");

	}



	*op = 0;

	return (op - ascii);

}
@@ -311,9 +315,11 @@ int fat_search_long(struct inode *inode, const unsigned char *name, 
	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;

	unsigned char nr_slots;

	int xlate_len;

	wchar_t *unicode = NULL;

	unsigned char work[MSDOS_NAME], bufname[260];	/* 256 + 4 */

	unsigned char work[MSDOS_NAME];

	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, const unsigned char *name, 
	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)
@@ -386,8 +396,8 @@ 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,
@@ -396,8 +406,8 @@ 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)) ||
@@ -416,6 +426,8 @@ 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);
@@ -598,7 +610,7 @@ 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;
@@ -610,7 +622,7 @@ 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;

fs/vfat/namei.c

+11 −14
Original line number Diff line number Diff line
@@ -176,15 +176,10 @@ static inline int vfat_is_used_badchars(const wchar_t *s, int len) 
	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] == ' ') /* last character cannot be space */

		return -EINVAL;

	if (len >= 256)

		return -ENAMETOOLONG;



	return 0;

}
@@ -485,11 +480,14 @@ xlate_to_uni(const unsigned char *name, int len, unsigned char *outname, 
		 */

		*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 +523,20 @@ xlate_to_uni(const unsigned char *name, int len, unsigned char *outname, 
					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 +574,6 @@ static int vfat_build_slots(struct inode *dir, const unsigned char *name, 
	loff_t offset;



	*nr_slots = 0;

	err = vfat_valid_longname(name, len);

	if (err)

		return err;



	page = __get_free_page(GFP_KERNEL);

	if (!page)

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