[CVE-2022-40303] Fix integer overflows with XML_PARSE_HUGE
Also impose size limits when XML_PARSE_HUGE is set. Limit size of names
to XML_MAX_TEXT_LENGTH (10 million bytes) and other content to
XML_MAX_HUGE_LENGTH (1 billion bytes).
Move some the length checks to the end of the respective loop to make
them strict.
xmlParseEntityValue didn't have a length limitation at all. But without
XML_PARSE_HUGE, this should eventually trigger an error in xmlGROW.
Thanks to Maddie Stone working with Google Project Zero for the report!
Bug: http://b/260709824
Test: TreeHugger
Merged-In: I3c735c190e95210d16001f6466aa6c73f45188b3
Change-Id: I67dd2cb590e2af64b46cc88277ce78a1f279427d
diff --git a/parser.c b/parser.c
index 5384e55..506c78a 100644
--- a/parser.c
+++ b/parser.c
@@ -115,6 +115,8 @@
* *
************************************************************************/
+#define XML_MAX_HUGE_LENGTH 1000000000
+
#define XML_PARSER_BIG_ENTITY 1000
#define XML_PARSER_LOT_ENTITY 5000
@@ -565,7 +567,7 @@
errmsg = "Malformed declaration expecting version";
break;
case XML_ERR_NAME_TOO_LONG:
- errmsg = "Name too long use XML_PARSE_HUGE option";
+ errmsg = "Name too long";
break;
#if 0
case:
@@ -3212,6 +3214,9 @@
int len = 0, l;
int c;
int count = 0;
+ int maxLength = (ctxt->options & XML_PARSE_HUGE) ?
+ XML_MAX_TEXT_LENGTH :
+ XML_MAX_NAME_LENGTH;
#ifdef DEBUG
nbParseNameComplex++;
@@ -3277,7 +3282,8 @@
if (ctxt->instate == XML_PARSER_EOF)
return(NULL);
}
- len += l;
+ if (len <= INT_MAX - l)
+ len += l;
NEXTL(l);
c = CUR_CHAR(l);
}
@@ -3303,13 +3309,13 @@
if (ctxt->instate == XML_PARSER_EOF)
return(NULL);
}
- len += l;
+ if (len <= INT_MAX - l)
+ len += l;
NEXTL(l);
c = CUR_CHAR(l);
}
}
- if ((len > XML_MAX_NAME_LENGTH) &&
- ((ctxt->options & XML_PARSE_HUGE) == 0)) {
+ if (len > maxLength) {
xmlFatalErr(ctxt, XML_ERR_NAME_TOO_LONG, "Name");
return(NULL);
}
@@ -3348,7 +3354,10 @@
xmlParseName(xmlParserCtxtPtr ctxt) {
const xmlChar *in;
const xmlChar *ret;
- int count = 0;
+ size_t count = 0;
+ size_t maxLength = (ctxt->options & XML_PARSE_HUGE) ?
+ XML_MAX_TEXT_LENGTH :
+ XML_MAX_NAME_LENGTH;
GROW;
@@ -3372,8 +3381,7 @@
in++;
if ((*in > 0) && (*in < 0x80)) {
count = in - ctxt->input->cur;
- if ((count > XML_MAX_NAME_LENGTH) &&
- ((ctxt->options & XML_PARSE_HUGE) == 0)) {
+ if (count > maxLength) {
xmlFatalErr(ctxt, XML_ERR_NAME_TOO_LONG, "Name");
return(NULL);
}
@@ -3394,6 +3402,9 @@
int len = 0, l;
int c;
int count = 0;
+ int maxLength = (ctxt->options & XML_PARSE_HUGE) ?
+ XML_MAX_TEXT_LENGTH :
+ XML_MAX_NAME_LENGTH;
size_t startPosition = 0;
#ifdef DEBUG
@@ -3414,17 +3425,13 @@
while ((c != ' ') && (c != '>') && (c != '/') && /* test bigname.xml */
(xmlIsNameChar(ctxt, c) && (c != ':'))) {
if (count++ > XML_PARSER_CHUNK_SIZE) {
- if ((len > XML_MAX_NAME_LENGTH) &&
- ((ctxt->options & XML_PARSE_HUGE) == 0)) {
- xmlFatalErr(ctxt, XML_ERR_NAME_TOO_LONG, "NCName");
- return(NULL);
- }
count = 0;
GROW;
if (ctxt->instate == XML_PARSER_EOF)
return(NULL);
}
- len += l;
+ if (len <= INT_MAX - l)
+ len += l;
NEXTL(l);
c = CUR_CHAR(l);
if (c == 0) {
@@ -3442,8 +3449,7 @@
c = CUR_CHAR(l);
}
}
- if ((len > XML_MAX_NAME_LENGTH) &&
- ((ctxt->options & XML_PARSE_HUGE) == 0)) {
+ if (len > maxLength) {
xmlFatalErr(ctxt, XML_ERR_NAME_TOO_LONG, "NCName");
return(NULL);
}
@@ -3469,7 +3475,10 @@
xmlParseNCName(xmlParserCtxtPtr ctxt) {
const xmlChar *in, *e;
const xmlChar *ret;
- int count = 0;
+ size_t count = 0;
+ size_t maxLength = (ctxt->options & XML_PARSE_HUGE) ?
+ XML_MAX_TEXT_LENGTH :
+ XML_MAX_NAME_LENGTH;
#ifdef DEBUG
nbParseNCName++;
@@ -3494,8 +3503,7 @@
goto complex;
if ((*in > 0) && (*in < 0x80)) {
count = in - ctxt->input->cur;
- if ((count > XML_MAX_NAME_LENGTH) &&
- ((ctxt->options & XML_PARSE_HUGE) == 0)) {
+ if (count > maxLength) {
xmlFatalErr(ctxt, XML_ERR_NAME_TOO_LONG, "NCName");
return(NULL);
}
@@ -3577,6 +3585,9 @@
const xmlChar *cur = *str;
int len = 0, l;
int c;
+ int maxLength = (ctxt->options & XML_PARSE_HUGE) ?
+ XML_MAX_TEXT_LENGTH :
+ XML_MAX_NAME_LENGTH;
#ifdef DEBUG
nbParseStringName++;
@@ -3612,12 +3623,6 @@
if (len + 10 > max) {
xmlChar *tmp;
- if ((len > XML_MAX_NAME_LENGTH) &&
- ((ctxt->options & XML_PARSE_HUGE) == 0)) {
- xmlFatalErr(ctxt, XML_ERR_NAME_TOO_LONG, "NCName");
- xmlFree(buffer);
- return(NULL);
- }
max *= 2;
tmp = (xmlChar *) xmlRealloc(buffer,
max * sizeof(xmlChar));
@@ -3631,14 +3636,18 @@
COPY_BUF(l,buffer,len,c);
cur += l;
c = CUR_SCHAR(cur, l);
+ if (len > maxLength) {
+ xmlFatalErr(ctxt, XML_ERR_NAME_TOO_LONG, "NCName");
+ xmlFree(buffer);
+ return(NULL);
+ }
}
buffer[len] = 0;
*str = cur;
return(buffer);
}
}
- if ((len > XML_MAX_NAME_LENGTH) &&
- ((ctxt->options & XML_PARSE_HUGE) == 0)) {
+ if (len > maxLength) {
xmlFatalErr(ctxt, XML_ERR_NAME_TOO_LONG, "NCName");
return(NULL);
}
@@ -3665,6 +3674,9 @@
int len = 0, l;
int c;
int count = 0;
+ int maxLength = (ctxt->options & XML_PARSE_HUGE) ?
+ XML_MAX_TEXT_LENGTH :
+ XML_MAX_NAME_LENGTH;
#ifdef DEBUG
nbParseNmToken++;
@@ -3716,12 +3728,6 @@
if (len + 10 > max) {
xmlChar *tmp;
- if ((max > XML_MAX_NAME_LENGTH) &&
- ((ctxt->options & XML_PARSE_HUGE) == 0)) {
- xmlFatalErr(ctxt, XML_ERR_NAME_TOO_LONG, "NmToken");
- xmlFree(buffer);
- return(NULL);
- }
max *= 2;
tmp = (xmlChar *) xmlRealloc(buffer,
max * sizeof(xmlChar));
@@ -3735,6 +3741,11 @@
COPY_BUF(l,buffer,len,c);
NEXTL(l);
c = CUR_CHAR(l);
+ if (len > maxLength) {
+ xmlFatalErr(ctxt, XML_ERR_NAME_TOO_LONG, "NmToken");
+ xmlFree(buffer);
+ return(NULL);
+ }
}
buffer[len] = 0;
return(buffer);
@@ -3742,8 +3753,7 @@
}
if (len == 0)
return(NULL);
- if ((len > XML_MAX_NAME_LENGTH) &&
- ((ctxt->options & XML_PARSE_HUGE) == 0)) {
+ if (len > maxLength) {
xmlFatalErr(ctxt, XML_ERR_NAME_TOO_LONG, "NmToken");
return(NULL);
}
@@ -3769,6 +3779,9 @@
int len = 0;
int size = XML_PARSER_BUFFER_SIZE;
int c, l;
+ int maxLength = (ctxt->options & XML_PARSE_HUGE) ?
+ XML_MAX_HUGE_LENGTH :
+ XML_MAX_TEXT_LENGTH;
xmlChar stop;
xmlChar *ret = NULL;
const xmlChar *cur = NULL;
@@ -3828,6 +3841,12 @@
GROW;
c = CUR_CHAR(l);
}
+
+ if (len > maxLength) {
+ xmlFatalErrMsg(ctxt, XML_ERR_ENTITY_NOT_FINISHED,
+ "entity value too long\n");
+ goto error;
+ }
}
buf[len] = 0;
if (ctxt->instate == XML_PARSER_EOF)
@@ -3915,6 +3934,9 @@
xmlChar *rep = NULL;
size_t len = 0;
size_t buf_size = 0;
+ size_t maxLength = (ctxt->options & XML_PARSE_HUGE) ?
+ XML_MAX_HUGE_LENGTH :
+ XML_MAX_TEXT_LENGTH;
int c, l, in_space = 0;
xmlChar *current = NULL;
xmlEntityPtr ent;
@@ -3946,16 +3968,6 @@
while (((NXT(0) != limit) && /* checked */
(IS_CHAR(c)) && (c != '<')) &&
(ctxt->instate != XML_PARSER_EOF)) {
- /*
- * Impose a reasonable limit on attribute size, unless XML_PARSE_HUGE
- * special option is given
- */
- if ((len > XML_MAX_TEXT_LENGTH) &&
- ((ctxt->options & XML_PARSE_HUGE) == 0)) {
- xmlFatalErrMsg(ctxt, XML_ERR_ATTRIBUTE_NOT_FINISHED,
- "AttValue length too long\n");
- goto mem_error;
- }
if (c == '&') {
in_space = 0;
if (NXT(1) == '#') {
@@ -4103,6 +4115,11 @@
}
GROW;
c = CUR_CHAR(l);
+ if (len > maxLength) {
+ xmlFatalErrMsg(ctxt, XML_ERR_ATTRIBUTE_NOT_FINISHED,
+ "AttValue length too long\n");
+ goto mem_error;
+ }
}
if (ctxt->instate == XML_PARSER_EOF)
goto error;
@@ -4124,16 +4141,6 @@
} else
NEXT;
- /*
- * There we potentially risk an overflow, don't allow attribute value of
- * length more than INT_MAX it is a very reasonable assumption !
- */
- if (len >= INT_MAX) {
- xmlFatalErrMsg(ctxt, XML_ERR_ATTRIBUTE_NOT_FINISHED,
- "AttValue length too long\n");
- goto mem_error;
- }
-
if (attlen != NULL) *attlen = (int) len;
return(buf);
@@ -4204,6 +4211,9 @@
int len = 0;
int size = XML_PARSER_BUFFER_SIZE;
int cur, l;
+ int maxLength = (ctxt->options & XML_PARSE_HUGE) ?
+ XML_MAX_TEXT_LENGTH :
+ XML_MAX_NAME_LENGTH;
xmlChar stop;
int state = ctxt->instate;
int count = 0;
@@ -4231,13 +4241,6 @@
if (len + 5 >= size) {
xmlChar *tmp;
- if ((size > XML_MAX_NAME_LENGTH) &&
- ((ctxt->options & XML_PARSE_HUGE) == 0)) {
- xmlFatalErr(ctxt, XML_ERR_NAME_TOO_LONG, "SystemLiteral");
- xmlFree(buf);
- ctxt->instate = (xmlParserInputState) state;
- return(NULL);
- }
size *= 2;
tmp = (xmlChar *) xmlRealloc(buf, size * sizeof(xmlChar));
if (tmp == NULL) {
@@ -4266,6 +4269,12 @@
SHRINK;
cur = CUR_CHAR(l);
}
+ if (len > maxLength) {
+ xmlFatalErr(ctxt, XML_ERR_NAME_TOO_LONG, "SystemLiteral");
+ xmlFree(buf);
+ ctxt->instate = (xmlParserInputState) state;
+ return(NULL);
+ }
}
buf[len] = 0;
ctxt->instate = (xmlParserInputState) state;
@@ -4293,6 +4302,9 @@
xmlChar *buf = NULL;
int len = 0;
int size = XML_PARSER_BUFFER_SIZE;
+ int maxLength = (ctxt->options & XML_PARSE_HUGE) ?
+ XML_MAX_TEXT_LENGTH :
+ XML_MAX_NAME_LENGTH;
xmlChar cur;
xmlChar stop;
int count = 0;
@@ -4320,12 +4332,6 @@
if (len + 1 >= size) {
xmlChar *tmp;
- if ((size > XML_MAX_NAME_LENGTH) &&
- ((ctxt->options & XML_PARSE_HUGE) == 0)) {
- xmlFatalErr(ctxt, XML_ERR_NAME_TOO_LONG, "Public ID");
- xmlFree(buf);
- return(NULL);
- }
size *= 2;
tmp = (xmlChar *) xmlRealloc(buf, size * sizeof(xmlChar));
if (tmp == NULL) {
@@ -4353,6 +4359,11 @@
SHRINK;
cur = CUR;
}
+ if (len > maxLength) {
+ xmlFatalErr(ctxt, XML_ERR_NAME_TOO_LONG, "Public ID");
+ xmlFree(buf);
+ return(NULL);
+ }
}
buf[len] = 0;
if (cur != stop) {
@@ -4752,6 +4763,9 @@
int r, rl;
int cur, l;
size_t count = 0;
+ size_t maxLength = (ctxt->options & XML_PARSE_HUGE) ?
+ XML_MAX_HUGE_LENGTH :
+ XML_MAX_TEXT_LENGTH;
int inputid;
inputid = ctxt->input->id;
@@ -4797,13 +4811,6 @@
if ((r == '-') && (q == '-')) {
xmlFatalErr(ctxt, XML_ERR_HYPHEN_IN_COMMENT, NULL);
}
- if ((len > XML_MAX_TEXT_LENGTH) &&
- ((ctxt->options & XML_PARSE_HUGE) == 0)) {
- xmlFatalErrMsgStr(ctxt, XML_ERR_COMMENT_NOT_FINISHED,
- "Comment too big found", NULL);
- xmlFree (buf);
- return;
- }
if (len + 5 >= size) {
xmlChar *new_buf;
size_t new_size;
@@ -4841,6 +4848,13 @@
GROW;
cur = CUR_CHAR(l);
}
+
+ if (len > maxLength) {
+ xmlFatalErrMsgStr(ctxt, XML_ERR_COMMENT_NOT_FINISHED,
+ "Comment too big found", NULL);
+ xmlFree (buf);
+ return;
+ }
}
buf[len] = 0;
if (cur == 0) {
@@ -4885,6 +4899,9 @@
xmlChar *buf = NULL;
size_t size = XML_PARSER_BUFFER_SIZE;
size_t len = 0;
+ size_t maxLength = (ctxt->options & XML_PARSE_HUGE) ?
+ XML_MAX_HUGE_LENGTH :
+ XML_MAX_TEXT_LENGTH;
xmlParserInputState state;
const xmlChar *in;
size_t nbchar = 0;
@@ -4968,8 +4985,7 @@
buf[len] = 0;
}
}
- if ((len > XML_MAX_TEXT_LENGTH) &&
- ((ctxt->options & XML_PARSE_HUGE) == 0)) {
+ if (len > maxLength) {
xmlFatalErrMsgStr(ctxt, XML_ERR_COMMENT_NOT_FINISHED,
"Comment too big found", NULL);
xmlFree (buf);
@@ -5169,6 +5185,9 @@
xmlChar *buf = NULL;
size_t len = 0;
size_t size = XML_PARSER_BUFFER_SIZE;
+ size_t maxLength = (ctxt->options & XML_PARSE_HUGE) ?
+ XML_MAX_HUGE_LENGTH :
+ XML_MAX_TEXT_LENGTH;
int cur, l;
const xmlChar *target;
xmlParserInputState state;
@@ -5244,14 +5263,6 @@
return;
}
count = 0;
- if ((len > XML_MAX_TEXT_LENGTH) &&
- ((ctxt->options & XML_PARSE_HUGE) == 0)) {
- xmlFatalErrMsgStr(ctxt, XML_ERR_PI_NOT_FINISHED,
- "PI %s too big found", target);
- xmlFree(buf);
- ctxt->instate = state;
- return;
- }
}
COPY_BUF(l,buf,len,cur);
NEXTL(l);
@@ -5261,15 +5272,14 @@
GROW;
cur = CUR_CHAR(l);
}
+ if (len > maxLength) {
+ xmlFatalErrMsgStr(ctxt, XML_ERR_PI_NOT_FINISHED,
+ "PI %s too big found", target);
+ xmlFree(buf);
+ ctxt->instate = state;
+ return;
+ }
}
- if ((len > XML_MAX_TEXT_LENGTH) &&
- ((ctxt->options & XML_PARSE_HUGE) == 0)) {
- xmlFatalErrMsgStr(ctxt, XML_ERR_PI_NOT_FINISHED,
- "PI %s too big found", target);
- xmlFree(buf);
- ctxt->instate = state;
- return;
- }
buf[len] = 0;
if (cur != '?') {
xmlFatalErrMsgStr(ctxt, XML_ERR_PI_NOT_FINISHED,
@@ -8961,6 +8971,9 @@
const xmlChar *in = NULL, *start, *end, *last;
xmlChar *ret = NULL;
int line, col;
+ int maxLength = (ctxt->options & XML_PARSE_HUGE) ?
+ XML_MAX_HUGE_LENGTH :
+ XML_MAX_TEXT_LENGTH;
GROW;
in = (xmlChar *) CUR_PTR;
@@ -9000,8 +9013,7 @@
start = in;
if (in >= end) {
GROW_PARSE_ATT_VALUE_INTERNAL(ctxt, in, start, end)
- if (((in - start) > XML_MAX_TEXT_LENGTH) &&
- ((ctxt->options & XML_PARSE_HUGE) == 0)) {
+ if ((in - start) > maxLength) {
xmlFatalErrMsg(ctxt, XML_ERR_ATTRIBUTE_NOT_FINISHED,
"AttValue length too long\n");
return(NULL);
@@ -9014,8 +9026,7 @@
if ((*in++ == 0x20) && (*in == 0x20)) break;
if (in >= end) {
GROW_PARSE_ATT_VALUE_INTERNAL(ctxt, in, start, end)
- if (((in - start) > XML_MAX_TEXT_LENGTH) &&
- ((ctxt->options & XML_PARSE_HUGE) == 0)) {
+ if ((in - start) > maxLength) {
xmlFatalErrMsg(ctxt, XML_ERR_ATTRIBUTE_NOT_FINISHED,
"AttValue length too long\n");
return(NULL);
@@ -9048,16 +9059,14 @@
last = last + delta;
}
end = ctxt->input->end;
- if (((in - start) > XML_MAX_TEXT_LENGTH) &&
- ((ctxt->options & XML_PARSE_HUGE) == 0)) {
+ if ((in - start) > maxLength) {
xmlFatalErrMsg(ctxt, XML_ERR_ATTRIBUTE_NOT_FINISHED,
"AttValue length too long\n");
return(NULL);
}
}
}
- if (((in - start) > XML_MAX_TEXT_LENGTH) &&
- ((ctxt->options & XML_PARSE_HUGE) == 0)) {
+ if ((in - start) > maxLength) {
xmlFatalErrMsg(ctxt, XML_ERR_ATTRIBUTE_NOT_FINISHED,
"AttValue length too long\n");
return(NULL);
@@ -9070,8 +9079,7 @@
col++;
if (in >= end) {
GROW_PARSE_ATT_VALUE_INTERNAL(ctxt, in, start, end)
- if (((in - start) > XML_MAX_TEXT_LENGTH) &&
- ((ctxt->options & XML_PARSE_HUGE) == 0)) {
+ if ((in - start) > maxLength) {
xmlFatalErrMsg(ctxt, XML_ERR_ATTRIBUTE_NOT_FINISHED,
"AttValue length too long\n");
return(NULL);
@@ -9079,8 +9087,7 @@
}
}
last = in;
- if (((in - start) > XML_MAX_TEXT_LENGTH) &&
- ((ctxt->options & XML_PARSE_HUGE) == 0)) {
+ if ((in - start) > maxLength) {
xmlFatalErrMsg(ctxt, XML_ERR_ATTRIBUTE_NOT_FINISHED,
"AttValue length too long\n");
return(NULL);
@@ -9770,6 +9777,9 @@
int s, sl;
int cur, l;
int count = 0;
+ int maxLength = (ctxt->options & XML_PARSE_HUGE) ?
+ XML_MAX_HUGE_LENGTH :
+ XML_MAX_TEXT_LENGTH;
/* Check 2.6.0 was NXT(0) not RAW */
if (CMP9(CUR_PTR, '<', '!', '[', 'C', 'D', 'A', 'T', 'A', '[')) {
@@ -9803,13 +9813,6 @@
if (len + 5 >= size) {
xmlChar *tmp;
- if ((size > XML_MAX_TEXT_LENGTH) &&
- ((ctxt->options & XML_PARSE_HUGE) == 0)) {
- xmlFatalErrMsgStr(ctxt, XML_ERR_CDATA_NOT_FINISHED,
- "CData section too big found", NULL);
- xmlFree (buf);
- return;
- }
tmp = (xmlChar *) xmlRealloc(buf, size * 2 * sizeof(xmlChar));
if (tmp == NULL) {
xmlFree(buf);
@@ -9836,6 +9839,12 @@
}
NEXTL(l);
cur = CUR_CHAR(l);
+ if (len > maxLength) {
+ xmlFatalErrMsg(ctxt, XML_ERR_CDATA_NOT_FINISHED,
+ "CData section too big found\n");
+ xmlFree(buf);
+ return;
+ }
}
buf[len] = 0;
ctxt->instate = XML_PARSER_CONTENT;