ksmbd: add support for surrogate pair conversion

ksmbd is missing supporting to convert filename included surrogate pair
characters. It triggers a "file or folder does not exist" error in
Windows client.

[Steps to Reproduce for bug]
1. Create surrogate pair file
 touch $(echo -e '\xf0\x9d\x9f\xa3')
 touch $(echo -e '\xf0\x9d\x9f\xa4')

2. Try to open these files in ksmbd share through Windows client.

This patch update unicode functions not to consider about surrogate pair
(and IVS).

Reviewed-by: Marios Makassikis <mmakassikis@freebox.fr>
Tested-by: Marios Makassikis <mmakassikis@freebox.fr>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
This commit is contained in:
Namjae Jeon 2023-10-21 21:01:20 +09:00 committed by Steve French
parent ecce70cf17
commit 0c180317c6

View File

@ -13,46 +13,10 @@
#include "unicode.h"
#include "smb_common.h"
/*
* smb_utf16_bytes() - how long will a string be after conversion?
* @from: pointer to input string
* @maxbytes: don't go past this many bytes of input string
* @codepage: destination codepage
*
* Walk a utf16le string and return the number of bytes that the string will
* be after being converted to the given charset, not including any null
* termination required. Don't walk past maxbytes in the source buffer.
*
* Return: string length after conversion
*/
static int smb_utf16_bytes(const __le16 *from, int maxbytes,
const struct nls_table *codepage)
{
int i;
int charlen, outlen = 0;
int maxwords = maxbytes / 2;
char tmp[NLS_MAX_CHARSET_SIZE];
__u16 ftmp;
for (i = 0; i < maxwords; i++) {
ftmp = get_unaligned_le16(&from[i]);
if (ftmp == 0)
break;
charlen = codepage->uni2char(ftmp, tmp, NLS_MAX_CHARSET_SIZE);
if (charlen > 0)
outlen += charlen;
else
outlen++;
}
return outlen;
}
/*
* cifs_mapchar() - convert a host-endian char to proper char in codepage
* @target: where converted character should be copied
* @src_char: 2 byte host-endian source character
* @from: host-endian source string
* @cp: codepage to which character should be converted
* @mapchar: should character be mapped according to mapchars mount option?
*
@ -63,10 +27,13 @@ static int smb_utf16_bytes(const __le16 *from, int maxbytes,
* Return: string length after conversion
*/
static int
cifs_mapchar(char *target, const __u16 src_char, const struct nls_table *cp,
cifs_mapchar(char *target, const __u16 *from, const struct nls_table *cp,
bool mapchar)
{
int len = 1;
__u16 src_char;
src_char = *from;
if (!mapchar)
goto cp_convert;
@ -104,12 +71,66 @@ out:
cp_convert:
len = cp->uni2char(src_char, target, NLS_MAX_CHARSET_SIZE);
if (len <= 0) {
*target = '?';
len = 1;
}
if (len <= 0)
goto surrogate_pair;
goto out;
surrogate_pair:
/* convert SURROGATE_PAIR and IVS */
if (strcmp(cp->charset, "utf8"))
goto unknown;
len = utf16s_to_utf8s(from, 3, UTF16_LITTLE_ENDIAN, target, 6);
if (len <= 0)
goto unknown;
return len;
unknown:
*target = '?';
len = 1;
goto out;
}
/*
* smb_utf16_bytes() - compute converted string length
* @from: pointer to input string
* @maxbytes: input string length
* @codepage: destination codepage
*
* Walk a utf16le string and return the number of bytes that the string will
* be after being converted to the given charset, not including any null
* termination required. Don't walk past maxbytes in the source buffer.
*
* Return: string length after conversion
*/
static int smb_utf16_bytes(const __le16 *from, int maxbytes,
const struct nls_table *codepage)
{
int i, j;
int charlen, outlen = 0;
int maxwords = maxbytes / 2;
char tmp[NLS_MAX_CHARSET_SIZE];
__u16 ftmp[3];
for (i = 0; i < maxwords; i++) {
ftmp[0] = get_unaligned_le16(&from[i]);
if (ftmp[0] == 0)
break;
for (j = 1; j <= 2; j++) {
if (i + j < maxwords)
ftmp[j] = get_unaligned_le16(&from[i + j]);
else
ftmp[j] = 0;
}
charlen = cifs_mapchar(tmp, ftmp, codepage, 0);
if (charlen > 0)
outlen += charlen;
else
outlen++;
}
return outlen;
}
/*
@ -139,12 +160,12 @@ cp_convert:
static int smb_from_utf16(char *to, const __le16 *from, int tolen, int fromlen,
const struct nls_table *codepage, bool mapchar)
{
int i, charlen, safelen;
int i, j, charlen, safelen;
int outlen = 0;
int nullsize = nls_nullsize(codepage);
int fromwords = fromlen / 2;
char tmp[NLS_MAX_CHARSET_SIZE];
__u16 ftmp;
__u16 ftmp[3]; /* ftmp[3] = 3array x 2bytes = 6bytes UTF-16 */
/*
* because the chars can be of varying widths, we need to take care
@ -155,9 +176,15 @@ static int smb_from_utf16(char *to, const __le16 *from, int tolen, int fromlen,
safelen = tolen - (NLS_MAX_CHARSET_SIZE + nullsize);
for (i = 0; i < fromwords; i++) {
ftmp = get_unaligned_le16(&from[i]);
if (ftmp == 0)
ftmp[0] = get_unaligned_le16(&from[i]);
if (ftmp[0] == 0)
break;
for (j = 1; j <= 2; j++) {
if (i + j < fromwords)
ftmp[j] = get_unaligned_le16(&from[i + j]);
else
ftmp[j] = 0;
}
/*
* check to see if converting this character might make the
@ -172,6 +199,19 @@ static int smb_from_utf16(char *to, const __le16 *from, int tolen, int fromlen,
/* put converted char into 'to' buffer */
charlen = cifs_mapchar(&to[outlen], ftmp, codepage, mapchar);
outlen += charlen;
/*
* charlen (=bytes of UTF-8 for 1 character)
* 4bytes UTF-8(surrogate pair) is charlen=4
* (4bytes UTF-16 code)
* 7-8bytes UTF-8(IVS) is charlen=3+4 or 4+4
* (2 UTF-8 pairs divided to 2 UTF-16 pairs)
*/
if (charlen == 4)
i++;
else if (charlen >= 5)
/* 5-6bytes UTF-8 */
i += 2;
}
/* properly null-terminate string */
@ -306,6 +346,9 @@ int smbConvertToUTF16(__le16 *target, const char *source, int srclen,
char src_char;
__le16 dst_char;
wchar_t tmp;
wchar_t wchar_to[6]; /* UTF-16 */
int ret;
unicode_t u;
if (!mapchars)
return smb_strtoUTF16(target, source, srclen, cp);
@ -348,11 +391,57 @@ int smbConvertToUTF16(__le16 *target, const char *source, int srclen,
* if no match, use question mark, which at least in
* some cases serves as wild card
*/
if (charlen < 1) {
dst_char = cpu_to_le16(0x003f);
charlen = 1;
if (charlen > 0)
goto ctoUTF16;
/* convert SURROGATE_PAIR */
if (strcmp(cp->charset, "utf8"))
goto unknown;
if (*(source + i) & 0x80) {
charlen = utf8_to_utf32(source + i, 6, &u);
if (charlen < 0)
goto unknown;
} else
goto unknown;
ret = utf8s_to_utf16s(source + i, charlen,
UTF16_LITTLE_ENDIAN,
wchar_to, 6);
if (ret < 0)
goto unknown;
i += charlen;
dst_char = cpu_to_le16(*wchar_to);
if (charlen <= 3)
/* 1-3bytes UTF-8 to 2bytes UTF-16 */
put_unaligned(dst_char, &target[j]);
else if (charlen == 4) {
/*
* 4bytes UTF-8(surrogate pair) to 4bytes UTF-16
* 7-8bytes UTF-8(IVS) divided to 2 UTF-16
* (charlen=3+4 or 4+4)
*/
put_unaligned(dst_char, &target[j]);
dst_char = cpu_to_le16(*(wchar_to + 1));
j++;
put_unaligned(dst_char, &target[j]);
} else if (charlen >= 5) {
/* 5-6bytes UTF-8 to 6bytes UTF-16 */
put_unaligned(dst_char, &target[j]);
dst_char = cpu_to_le16(*(wchar_to + 1));
j++;
put_unaligned(dst_char, &target[j]);
dst_char = cpu_to_le16(*(wchar_to + 2));
j++;
put_unaligned(dst_char, &target[j]);
}
continue;
unknown:
dst_char = cpu_to_le16(0x003f);
charlen = 1;
}
ctoUTF16:
/*
* character may take more than one byte in the source string,
* but will take exactly two bytes in the target string