Magic-Mirror/gecko-dev
1
0
Fork 0
mirror of https://github.com/mozilla/gecko-dev.git synced 2024-10-13 13:25:37 +00:00
Code Issues Actions Packages Projects Releases Wiki Activity

bug 552308 - add arithmetic overflow checks in woff encoding routines (NPOTB). r=dveditz

Browse Source
This commit is contained in:
Jonathan Kew 2010-05-12 13:17:58 +01:00
parent 901d200bbe
commit 6d364c5257
1 changed files with 48 additions and 5 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

53
gfx/thebes/src/woff.c
View File

@ -89,10 +89,15 @@ calcChecksum(const sfntDirEntry * dirEntry,
const uint32_t * csumPtr;
const uint32_t * csumEnd;
uint32_t csum = 0;
uint32_t length = LONGALIGN(READ32BE(dirEntry->length));
uint32_t length = READ32BE(dirEntry->length);
uint32_t offset = READ32BE(dirEntry->offset);
uint32_t tag;
if ((offset & 3) != 0) {
if (LONGALIGN(length) < length) { /* overflow */
return csum;
} else {
length = LONGALIGN(length);
}
if ((offset & 3) != 0) { /* invalid - not properly aligned */
return csum;
}
if (length > sfntLen || offset > sfntLen - length) {
@ -224,6 +229,9 @@ woffEncode(const uint8_t * sfntData, uint32_t sfntLen,
if (tag == TABLE_TAG_DSIG) {
status |= eWOFF_warn_removed_DSIG;
removedDsigSize = READ32BE(sfntDir[tableIndex].length);
if (LONGALIGN(removedDsigSize) < removedDsigSize) {
FAIL(eWOFF_invalid);
}
continue;
}
}
@ -235,6 +243,7 @@ woffEncode(const uint8_t * sfntData, uint32_t sfntLen,
qsort(tableOrder, numTables, sizeof(tableOrderRec), compareOffsets);
/* initially, allocate space for header and directory */
/* cannot be too big because numTables is 16-bit */
tableOffset = sizeof(woffHeader) + numTables * sizeof(woffDirEntry);
woffData = (uint8_t *) malloc(tableOffset);
if (!woffData) {
@ -282,7 +291,15 @@ woffEncode(const uint8_t * sfntData, uint32_t sfntLen,
if (sourceLen > sfntLen || sourceOffset > sfntLen - sourceLen) {
FAIL(eWOFF_invalid);
}
destLen = LONGALIGN(compressBound(sourceLen));
destLen = compressBound(sourceLen);
if (LONGALIGN(destLen) < destLen) {
/* something weird is going on if this overflows! */
FAIL(eWOFF_invalid);
}
destLen = LONGALIGN(destLen);
if (tableOffset + destLen < tableOffset) {
FAIL(eWOFF_invalid);
}
woffData = (uint8_t *) realloc(woffData, tableOffset + destLen);
if (!woffData) {
FAIL(eWOFF_out_of_memory);
@ -296,13 +313,19 @@ woffEncode(const uint8_t * sfntData, uint32_t sfntLen,
}
if (destLen < sourceLen) {
/* compressed table was smaller */
tableOffset += destLen;
tableOffset += destLen; /* checked for potential overflow above */
WOFFDIR[newIndex].compLen = READ32BE(destLen);
} else {
/* compression didn't make it smaller, so store original data instead */
if (LONGALIGN(sourceLen) < sourceLen) {
FAIL(eWOFF_invalid); /* overflow, bail out */
}
destLen = sourceLen;
/* reallocate to ensure enough space for the table,
plus potential padding after it */
if (tableOffset + LONGALIGN(sourceLen) < tableOffset) {
FAIL(eWOFF_invalid); /* overflow, bail out */
}
woffData = (uint8_t *) realloc(woffData,
tableOffset + LONGALIGN(sourceLen));
if (!woffData) {
@ -311,12 +334,21 @@ woffEncode(const uint8_t * sfntData, uint32_t sfntLen,
/* copy the original data into place */
memcpy(woffData + tableOffset,
sfntData + READ32BE(sfntDir[oldIndex].offset), sourceLen);
if (tableOffset + sourceLen < tableOffset) {
FAIL(eWOFF_invalid); /* overflow, bail out */
}
tableOffset += sourceLen;
WOFFDIR[newIndex].compLen = WOFFDIR[newIndex].origLen;
}
/* update total size of uncompressed OpenType with table size */
if (totalSfntSize + sourceLen < totalSfntSize) {
FAIL(eWOFF_invalid); /* overflow, bail out */
}
totalSfntSize += sourceLen;
if (LONGALIGN(totalSfntSize) < totalSfntSize) {
FAIL(eWOFF_invalid);
}
totalSfntSize = LONGALIGN(totalSfntSize);
}
@ -442,10 +474,20 @@ rebuildWoff(const uint8_t * woffData, uint32_t * woffLen,
totalSize = tableLimit; /* already long-aligned */
if (metaCompLen) {
if (totalSize + metaCompLen < totalSize) {
FAIL(eWOFF_invalid);
}
totalSize += metaCompLen;
}
if (privLen) {
totalSize = LONGALIGN(totalSize) + privLen;
if (LONGALIGN(totalSize) < totalSize) {
FAIL(eWOFF_invalid);
}
totalSize = LONGALIGN(totalSize);
if (totalSize + privLen < totalSize) {
FAIL(eWOFF_invalid);
}
totalSize += privLen;
}
newData = malloc(totalSize);
if (!newData) {
@ -771,6 +813,7 @@ woffDecodeToBufferInternal(const uint8_t * woffData, uint32_t woffLen,
}
newHeader->entrySelector = READ16BE(entrySelector);
/* cannot be too big because numTables is 16-bit */
tableOrder = (tableOrderRec *) malloc(numTables * sizeof(tableOrderRec));
if (!tableOrder) {
FAIL(eWOFF_out_of_memory);