On Thu, Dec 08, 2005 at 12:12:09AM +1100, Hamish Moffatt wrote:
> On Wed, Dec 07, 2005 at 02:00:55PM +0100, Jan Niehusmann wrote:
> > Ok, so you noticed that my analysis was not completely correct - while
> > the woody version indeed doesn't contain JPXStream.cc (and consequently,
> > the JPX stream reader bug doesn't exist in woody), the other security
> > holes (in Stream.cc) do exist in woody and need patching.
>
> I'll work on that next, but it won't be for a day or two due to time
> constraints. It looks like a bit more work that woody. You are welcome
> to work on it if you like.
Well I don't have time to verify that all holes are actually closed, but
the attached patch applies cleanly, and the result does compile on sarge
(not tested on woody, as I don't have an installation available).
Jan
diff -ur xpdf-1.00-o/xpdf/Stream.cc xpdf-1.00/xpdf/Stream.cc
--- xpdf-1.00-o/xpdf/Stream.cc 2002-02-02 00:15:45.000000000 +0100
+++ xpdf-1.00/xpdf/Stream.cc 2005-12-07 15:34:21.000000000 +0100
@@ -400,18 +400,33 @@
StreamPredictor::StreamPredictor(Stream *strA, int predictorA,
int widthA, int nCompsA, int nBitsA) {
+ int totalBits;
+
str = strA;
predictor = predictorA;
width = widthA;
nComps = nCompsA;
nBits = nBitsA;
+ predLine = NULL;
+ ok = gFalse;
nVals = width * nComps;
+ totalBits = nVals * nBits;
+ if (totalBits == 0 ||
+ (totalBits / nBits) / nComps != width ||
+ totalBits + 7 < 0) {
+ return;
+ }
pixBytes = (nComps * nBits + 7) >> 3;
- rowBytes = ((nVals * nBits + 7) >> 3) + pixBytes;
+ rowBytes = ((totalBits + 7) >> 3) + pixBytes;
+ if (rowBytes < 0) {
+ return;
+ }
predLine = (Guchar *)gmalloc(rowBytes);
memset(predLine, 0, rowBytes);
predIdx = rowBytes;
+
+ ok = gTrue;
}
StreamPredictor::~StreamPredictor() {
@@ -852,6 +867,10 @@
FilterStream(strA) {
if (predictor != 1) {
pred = new StreamPredictor(this, predictor, columns, colors, bits);
+ if (!pred->isOk()) {
+ delete pred;
+ pred = NULL;
+ }
} else {
pred = NULL;
}
@@ -2535,6 +2554,14 @@
height = read16();
width = read16();
numComps = str->getChar();
+ if (numComps <= 0 || numComps > 4) {
+ error(getPos(), "Bad number of components in DCT stream", prec);
+ return gFalse;
+ }
+ if (numComps <= 0 || numComps > 4) {
+ error(getPos(), "Bad number of components in DCT stream", prec);
+ return gFalse;
+ }
length -= 6;
if (prec != 8) {
error(getPos(), "Bad DCT precision %d", prec);
@@ -2815,6 +2842,10 @@
FilterStream(strA) {
if (predictor != 1) {
pred = new StreamPredictor(this, predictor, columns, colors, bits);
+ if (!pred->isOk()) {
+ delete pred;
+ pred = NULL;
+ }
} else {
pred = NULL;
}
diff -ur xpdf-1.00-o/xpdf/Stream.h xpdf-1.00/xpdf/Stream.h
--- xpdf-1.00-o/xpdf/Stream.h 2002-02-02 00:15:45.000000000 +0100
+++ xpdf-1.00/xpdf/Stream.h 2005-12-07 15:34:21.000000000 +0100
@@ -214,6 +214,8 @@
~StreamPredictor();
+ GBool isOk() { return ok; }
+
int lookChar();
int getChar();
@@ -231,6 +233,7 @@
int rowBytes; // bytes per line
Guchar *predLine; // line buffer
int predIdx; // current index in predLine
+ GBool ok;
};
//------------------------------------------------------------------------
