diff options
Diffstat (limited to 'package/libxml2/libxml2-2.7.8-hardening-xpath.patch')
-rw-r--r-- | package/libxml2/libxml2-2.7.8-hardening-xpath.patch | 224 |
1 files changed, 224 insertions, 0 deletions
diff --git a/package/libxml2/libxml2-2.7.8-hardening-xpath.patch b/package/libxml2/libxml2-2.7.8-hardening-xpath.patch new file mode 100644 index 000000000..8e699ec8c --- /dev/null +++ b/package/libxml2/libxml2-2.7.8-hardening-xpath.patch @@ -0,0 +1,224 @@ +From f5048b3e71fc30ad096970b8df6e7af073bae4cb Mon Sep 17 00:00:00 2001 +From: Daniel Veillard <veillard@redhat.com> +Date: Thu, 18 Aug 2011 09:10:13 +0000 +Subject: Hardening of XPath evaluation + +Add a mechanism of frame for XPath evaluation when entering a function +or a scoped evaluation, also fix a potential problem in predicate +evaluation. +--- +diff --git a/include/libxml/xpath.h b/include/libxml/xpath.h +index 1a9e30e..ddd9dd8 100644 +--- a/include/libxml/xpath.h ++++ b/include/libxml/xpath.h +@@ -68,7 +68,8 @@ typedef enum { + XPATH_UNDEF_PREFIX_ERROR, + XPATH_ENCODING_ERROR, + XPATH_INVALID_CHAR_ERROR, +- XPATH_INVALID_CTXT ++ XPATH_INVALID_CTXT, ++ XPATH_STACK_ERROR + } xmlXPathError; + + /* +@@ -380,6 +381,8 @@ struct _xmlXPathParserContext { + xmlXPathCompExprPtr comp; /* the precompiled expression */ + int xptr; /* it this an XPointer expression */ + xmlNodePtr ancestor; /* used for walking preceding axis */ ++ ++ int valueFrame; /* used to limit Pop on the stack */ + }; + + /************************************************************************ +diff --git a/xpath.c b/xpath.c +index b59ac5a..bcee2ea 100644 +--- a/xpath.c ++++ b/xpath.c +@@ -252,6 +252,7 @@ static const char *xmlXPathErrorMessages[] = { + "Encoding error\n", + "Char out of XML range\n", + "Invalid or incomplete context\n", ++ "Stack usage errror\n", + "?? Unknown error ??\n" /* Must be last in the list! */ + }; + #define MAXERRNO ((int)(sizeof(xmlXPathErrorMessages) / \ +@@ -2398,6 +2399,42 @@ xmlXPathCacheConvertNumber(xmlXPathContextPtr ctxt, xmlXPathObjectPtr val) { + ************************************************************************/ + + /** ++ * xmlXPathSetFrame: ++ * @ctxt: an XPath parser context ++ * ++ * Set the callee evaluation frame ++ * ++ * Returns the previous frame value to be restored once done ++ */ ++static int ++xmlXPathSetFrame(xmlXPathParserContextPtr ctxt) { ++ int ret; ++ ++ if (ctxt == NULL) ++ return(0); ++ ret = ctxt->valueFrame; ++ ctxt->valueFrame = ctxt->valueNr; ++ return(ret); ++} ++ ++/** ++ * xmlXPathPopFrame: ++ * @ctxt: an XPath parser context ++ * @frame: the previous frame value ++ * ++ * Remove the callee evaluation frame ++ */ ++static void ++xmlXPathPopFrame(xmlXPathParserContextPtr ctxt, int frame) { ++ if (ctxt == NULL) ++ return; ++ if (ctxt->valueNr < ctxt->valueFrame) { ++ xmlXPatherror(ctxt, __FILE__, __LINE__, XPATH_STACK_ERROR); ++ } ++ ctxt->valueFrame = frame; ++} ++ ++/** + * valuePop: + * @ctxt: an XPath evaluation context + * +@@ -2412,6 +2449,12 @@ valuePop(xmlXPathParserContextPtr ctxt) + + if ((ctxt == NULL) || (ctxt->valueNr <= 0)) + return (NULL); ++ ++ if (ctxt->valueNr <= ctxt->valueFrame) { ++ xmlXPatherror(ctxt, __FILE__, __LINE__, XPATH_STACK_ERROR); ++ return (NULL); ++ } ++ + ctxt->valueNr--; + if (ctxt->valueNr > 0) + ctxt->value = ctxt->valueTab[ctxt->valueNr - 1]; +@@ -6154,6 +6197,7 @@ xmlXPathCompParserContext(xmlXPathCompExprPtr comp, xmlXPathContextPtr ctxt) { + ret->valueNr = 0; + ret->valueMax = 10; + ret->value = NULL; ++ ret->valueFrame = 0; + + ret->context = ctxt; + ret->comp = comp; +@@ -11711,6 +11755,7 @@ xmlXPathCompOpEvalPositionalPredicate(xmlXPathParserContextPtr ctxt, + xmlXPathObjectPtr contextObj = NULL, exprRes = NULL; + xmlNodePtr oldContextNode, contextNode = NULL; + xmlXPathContextPtr xpctxt = ctxt->context; ++ int frame; + + #ifdef LIBXML_XPTR_ENABLED + /* +@@ -11730,6 +11775,8 @@ xmlXPathCompOpEvalPositionalPredicate(xmlXPathParserContextPtr ctxt, + */ + exprOp = &ctxt->comp->steps[op->ch2]; + for (i = 0; i < set->nodeNr; i++) { ++ xmlXPathObjectPtr tmp; ++ + if (set->nodeTab[i] == NULL) + continue; + +@@ -11757,23 +11804,25 @@ xmlXPathCompOpEvalPositionalPredicate(xmlXPathParserContextPtr ctxt, + xmlXPathNodeSetAddUnique(contextObj->nodesetval, + contextNode); + ++ frame = xmlXPathSetFrame(ctxt); + valuePush(ctxt, contextObj); + res = xmlXPathCompOpEvalToBoolean(ctxt, exprOp, 1); ++ tmp = valuePop(ctxt); ++ xmlXPathPopFrame(ctxt, frame); + + if ((ctxt->error != XPATH_EXPRESSION_OK) || (res == -1)) { +- xmlXPathObjectPtr tmp; +- /* pop the result if any */ +- tmp = valuePop(ctxt); +- if (tmp != contextObj) { ++ while (tmp != contextObj) { + /* + * Free up the result + * then pop off contextObj, which will be freed later + */ + xmlXPathReleaseObject(xpctxt, tmp); +- valuePop(ctxt); ++ tmp = valuePop(ctxt); + } + goto evaluation_error; + } ++ /* push the result back onto the stack */ ++ valuePush(ctxt, tmp); + + if (res) + pos++; +@@ -13377,7 +13426,9 @@ xmlXPathCompOpEval(xmlXPathParserContextPtr ctxt, xmlXPathStepOpPtr op) + xmlXPathFunction func; + const xmlChar *oldFunc, *oldFuncURI; + int i; ++ int frame; + ++ frame = xmlXPathSetFrame(ctxt); + if (op->ch1 != -1) + total += + xmlXPathCompOpEval(ctxt, &comp->steps[op->ch1]); +@@ -13385,15 +13436,18 @@ xmlXPathCompOpEval(xmlXPathParserContextPtr ctxt, xmlXPathStepOpPtr op) + xmlGenericError(xmlGenericErrorContext, + "xmlXPathCompOpEval: parameter error\n"); + ctxt->error = XPATH_INVALID_OPERAND; ++ xmlXPathPopFrame(ctxt, frame); + return (total); + } +- for (i = 0; i < op->value; i++) ++ for (i = 0; i < op->value; i++) { + if (ctxt->valueTab[(ctxt->valueNr - 1) - i] == NULL) { + xmlGenericError(xmlGenericErrorContext, + "xmlXPathCompOpEval: parameter error\n"); + ctxt->error = XPATH_INVALID_OPERAND; ++ xmlXPathPopFrame(ctxt, frame); + return (total); + } ++ } + if (op->cache != NULL) + XML_CAST_FPTR(func) = op->cache; + else { +@@ -13409,6 +13463,7 @@ xmlXPathCompOpEval(xmlXPathParserContextPtr ctxt, xmlXPathStepOpPtr op) + xmlGenericError(xmlGenericErrorContext, + "xmlXPathCompOpEval: function %s bound to undefined prefix %s\n", + (char *)op->value4, (char *)op->value5); ++ xmlXPathPopFrame(ctxt, frame); + return (total); + } + func = xmlXPathFunctionLookupNS(ctxt->context, +@@ -13430,6 +13485,7 @@ xmlXPathCompOpEval(xmlXPathParserContextPtr ctxt, xmlXPathStepOpPtr op) + func(ctxt, op->value); + ctxt->context->function = oldFunc; + ctxt->context->functionURI = oldFuncURI; ++ xmlXPathPopFrame(ctxt, frame); + return (total); + } + case XPATH_OP_ARG: +@@ -14333,6 +14389,7 @@ xmlXPathRunEval(xmlXPathParserContextPtr ctxt, int toBool) + ctxt->valueNr = 0; + ctxt->valueMax = 10; + ctxt->value = NULL; ++ ctxt->valueFrame = 0; + } + #ifdef XPATH_STREAMING + if (ctxt->comp->stream) { +diff --git a/xpointer.c b/xpointer.c +index 7a42d02..37afa3a 100644 +--- a/xpointer.c ++++ b/xpointer.c +@@ -1269,6 +1269,7 @@ xmlXPtrEvalXPointer(xmlXPathParserContextPtr ctxt) { + ctxt->valueNr = 0; + ctxt->valueMax = 10; + ctxt->value = NULL; ++ ctxt->valueFrame = 0; + } + SKIP_BLANKS; + if (CUR == '/') { +-- +cgit v0.9.0.2 |