Prevent overflow beyond the end of string in wtf_parse1()

Bug-Debian: https://github.com/tats/w3m/issues/68
This commit is contained in:
Tatsuya Kinoshita
2016-12-24 21:21:49 +09:00
parent f51c0966a4
commit 00433f4ac2

View File

@@ -397,7 +397,7 @@ wtf_parse1(wc_uchar **p)
cc.code = *(q++); cc.code = *(q++);
} else if (*q > 0xa0) { } else if (*q > 0xa0) {
cc.ccs = wtf_gr_ccs; cc.ccs = wtf_gr_ccs;
if (WC_CCS_IS_WIDE(cc.ccs)) { if (WC_CCS_IS_WIDE(cc.ccs) && *(q+1)) {
cc.code = ((wc_uint32)*q << 8) | *(q+1); cc.code = ((wc_uint32)*q << 8) | *(q+1);
q += 2; q += 2;
} else } else
@@ -410,27 +410,47 @@ wtf_parse1(wc_uchar **p)
case WC_CCS_A_CS942: case WC_CCS_A_CS942:
case WC_CCS_A_PCS: case WC_CCS_A_PCS:
case WC_CCS_A_UNKNOWN: case WC_CCS_A_UNKNOWN:
cc.ccs |= *(q++) & 0x7f; if (*q && *(q+1)) {
cc.code = *(q++); cc.ccs |= *(q++) & 0x7f;
cc.code = *(q++);
} else {
cc.ccs = WC_CCS_US_ASCII;
cc.code = (wc_uint32)' ';
}
break; break;
case WC_CCS_A_CS94W: case WC_CCS_A_CS94W:
case WC_CCS_A_CS96W: case WC_CCS_A_CS96W:
case WC_CCS_A_PCSW: case WC_CCS_A_PCSW:
cc.ccs |= *(q++) & 0x7f; if (*q && *(q+1) && *(q+2)) {
cc.code = ((wc_uint32)*q << 8) | *(q+1); cc.ccs |= *(q++) & 0x7f;
q += 2; cc.code = ((wc_uint32)*q << 8) | *(q+1);
q += 2;
} else {
cc.ccs = WC_CCS_US_ASCII;
cc.code = (wc_uint32)' ';
}
break; break;
case WC_CCS_A_WCS16: case WC_CCS_A_WCS16:
case WC_CCS_A_WCS16W: case WC_CCS_A_WCS16W:
cc.ccs |= (*q & 0x7c) >> 2; if (*q && *(q+1) && *(q+2)) {
cc.code = wtf_to_wcs16(q); cc.ccs |= (*q & 0x7c) >> 2;
q += 3; cc.code = wtf_to_wcs16(q);
q += 3;
} else {
cc.ccs = WC_CCS_US_ASCII;
cc.code = (wc_uint32)' ';
}
break; break;
case WC_CCS_A_WCS32: case WC_CCS_A_WCS32:
case WC_CCS_A_WCS32W: case WC_CCS_A_WCS32W:
cc.ccs |= (*q & 0x70) >> 4; if (*q && *(q+1) && *(q+2) && *(q+3) && *(q+4)) {
cc.code = wtf_to_wcs32(q); cc.ccs |= (*q & 0x70) >> 4;
q += 5; cc.code = wtf_to_wcs32(q);
q += 5;
} else {
cc.ccs = WC_CCS_US_ASCII;
cc.code = (wc_uint32)' ';
}
break; break;
default: default:
/* case 0: */ /* case 0: */