bpo-30947: Update libexpat from 2.2.1 to 2.2.3 (#3106)
* bpo-30947: Update libexpat from 2.2.1 to 2.2.3
* Add NEWS entry
* Add new loadlibrary.c
* expat_external.h: restore include "pyexpatns.h"
* PCbuild: add expat/loadlibrary.c
* Define XML_POOR_ENTROPY to compile expat
diff --git a/Modules/expat/xmlparse.c b/Modules/expat/xmlparse.c
index daec151..b703e61 100644
--- a/Modules/expat/xmlparse.c
+++ b/Modules/expat/xmlparse.c
@@ -1,10 +1,12 @@
/* Copyright (c) 1998, 1999, 2000 Thai Open Source Software Center Ltd
See the file COPYING for copying permission.
- 77fea421d361dca90041d0040ecf1dca651167fadf2af79e990e35168d70d933 (2.2.1+)
+ 101bfd65d1ff3d1511cf6671e6aae65f82cd97df6f4da137d46d510731830ad9 (2.2.3+)
*/
-#define _GNU_SOURCE 1 /* syscall prototype */
+#if !defined(_GNU_SOURCE)
+# define _GNU_SOURCE 1 /* syscall prototype */
+#endif
#include <stddef.h>
#include <string.h> /* memset(), memcpy() */
@@ -19,6 +21,8 @@
#include <sys/time.h> /* gettimeofday() */
#include <sys/types.h> /* getpid() */
#include <unistd.h> /* getpid() */
+#include <fcntl.h> /* O_RDONLY */
+#include <errno.h>
#endif
#define XML_BUILDING_EXPAT 1
@@ -33,6 +37,57 @@
#include "expat.h"
#include "siphash.h"
+#if defined(HAVE_GETRANDOM) || defined(HAVE_SYSCALL_GETRANDOM)
+# if defined(HAVE_GETRANDOM)
+# include <sys/random.h> /* getrandom */
+# else
+# include <unistd.h> /* syscall */
+# include <sys/syscall.h> /* SYS_getrandom */
+# endif
+# if ! defined(GRND_NONBLOCK)
+# define GRND_NONBLOCK 0x0001
+# endif /* defined(GRND_NONBLOCK) */
+#endif /* defined(HAVE_GETRANDOM) || defined(HAVE_SYSCALL_GETRANDOM) */
+
+#if defined(HAVE_LIBBSD) \
+ && (defined(HAVE_ARC4RANDOM_BUF) || defined(HAVE_ARC4RANDOM))
+# include <bsd/stdlib.h>
+#endif
+
+#if defined(_WIN32) && !defined(LOAD_LIBRARY_SEARCH_SYSTEM32)
+# define LOAD_LIBRARY_SEARCH_SYSTEM32 0x00000800
+#endif
+
+#if !defined(HAVE_GETRANDOM) && !defined(HAVE_SYSCALL_GETRANDOM) \
+ && !defined(HAVE_ARC4RANDOM_BUF) && !defined(HAVE_ARC4RANDOM) \
+ && !defined(XML_DEV_URANDOM) \
+ && !defined(_WIN32) \
+ && !defined(XML_POOR_ENTROPY)
+# error \
+ You do not have support for any sources of high quality entropy \
+ enabled. For end user security, that is probably not what you want. \
+ \
+ Your options include: \
+ * Linux + glibc >=2.25 (getrandom): HAVE_GETRANDOM, \
+ * Linux + glibc <2.25 (syscall SYS_getrandom): HAVE_SYSCALL_GETRANDOM, \
+ * BSD / macOS >=10.7 (arc4random_buf): HAVE_ARC4RANDOM_BUF, \
+ * BSD / macOS <10.7 (arc4random): HAVE_ARC4RANDOM, \
+ * libbsd (arc4random_buf): HAVE_ARC4RANDOM_BUF + HAVE_LIBBSD, \
+ * libbsd (arc4random): HAVE_ARC4RANDOM + HAVE_LIBBSD, \
+ * Linux / BSD / macOS (/dev/urandom): XML_DEV_URANDOM \
+ * Windows (RtlGenRandom): _WIN32. \
+ \
+ If insist on not using any of these, bypass this error by defining \
+ XML_POOR_ENTROPY; you have been warned. \
+ \
+ For CMake, one way to pass the define is: \
+ cmake -DCMAKE_C_FLAGS="-pipe -O2 -DHAVE_SYSCALL_GETRANDOM" . \
+ \
+ If you have reasons to patch this detection code away or need changes \
+ to the build system, please open a bug. Thank you!
+#endif
+
+
#ifdef XML_UNICODE
#define XML_ENCODE_MAX XML_UTF16_ENCODE_MAX
#define XmlConvert XmlUtf16Convert
@@ -436,6 +491,9 @@
getElementType(XML_Parser parser, const ENCODING *enc,
const char *ptr, const char *end);
+static XML_Char *copyString(const XML_Char *s,
+ const XML_Memory_Handling_Suite *memsuite);
+
static unsigned long generate_hash_secret_salt(XML_Parser parser);
static XML_Bool startParsing(XML_Parser parser);
@@ -696,21 +754,13 @@
#if defined(HAVE_GETRANDOM) || defined(HAVE_SYSCALL_GETRANDOM)
-# include <errno.h>
-
-# if defined(HAVE_GETRANDOM)
-# include <sys/random.h> /* getrandom */
-# else
-# include <unistd.h> /* syscall */
-# include <sys/syscall.h> /* SYS_getrandom */
-# endif
/* Obtain entropy on Linux 3.17+ */
static int
-writeRandomBytes_getrandom(void * target, size_t count) {
+writeRandomBytes_getrandom_nonblock(void * target, size_t count) {
int success = 0; /* full count bytes written? */
size_t bytesWrittenTotal = 0;
- const unsigned int getrandomFlags = 0;
+ const unsigned int getrandomFlags = GRND_NONBLOCK;
do {
void * const currentTarget = (void*)((char*)target + bytesWrittenTotal);
@@ -728,7 +778,7 @@
if (bytesWrittenTotal >= count)
success = 1;
}
- } while (! success && (errno == EINTR || errno == EAGAIN));
+ } while (! success && (errno == EINTR));
return success;
}
@@ -736,12 +786,67 @@
#endif /* defined(HAVE_GETRANDOM) || defined(HAVE_SYSCALL_GETRANDOM) */
+#if ! defined(_WIN32) && defined(XML_DEV_URANDOM)
+
+/* Extract entropy from /dev/urandom */
+static int
+writeRandomBytes_dev_urandom(void * target, size_t count) {
+ int success = 0; /* full count bytes written? */
+ size_t bytesWrittenTotal = 0;
+
+ const int fd = open("/dev/urandom", O_RDONLY);
+ if (fd < 0) {
+ return 0;
+ }
+
+ do {
+ void * const currentTarget = (void*)((char*)target + bytesWrittenTotal);
+ const size_t bytesToWrite = count - bytesWrittenTotal;
+
+ const ssize_t bytesWrittenMore = read(fd, currentTarget, bytesToWrite);
+
+ if (bytesWrittenMore > 0) {
+ bytesWrittenTotal += bytesWrittenMore;
+ if (bytesWrittenTotal >= count)
+ success = 1;
+ }
+ } while (! success && (errno == EINTR));
+
+ close(fd);
+ return success;
+}
+
+#endif /* ! defined(_WIN32) && defined(XML_DEV_URANDOM) */
+
+
+#if defined(HAVE_ARC4RANDOM)
+
+static void
+writeRandomBytes_arc4random(void * target, size_t count) {
+ size_t bytesWrittenTotal = 0;
+
+ while (bytesWrittenTotal < count) {
+ const uint32_t random32 = arc4random();
+ size_t i = 0;
+
+ for (; (i < sizeof(random32)) && (bytesWrittenTotal < count);
+ i++, bytesWrittenTotal++) {
+ const uint8_t random8 = (uint8_t)(random32 >> (i * 8));
+ ((uint8_t *)target)[bytesWrittenTotal] = random8;
+ }
+ }
+}
+
+#endif /* defined(HAVE_ARC4RANDOM) */
+
+
#ifdef _WIN32
typedef BOOLEAN (APIENTRY *RTLGENRANDOM_FUNC)(PVOID, ULONG);
+HMODULE _Expat_LoadLibrary(LPCTSTR filename); /* see loadlibrary.c */
/* Obtain entropy on Windows XP / Windows Server 2003 and later.
- * Hint on RtlGenRandom and the following article from libsodioum.
+ * Hint on RtlGenRandom and the following article from libsodium.
*
* Michael Howard: Cryptographically Secure Random number on Windows without using CryptoAPI
* https://blogs.msdn.microsoft.com/michael_howard/2005/01/14/cryptographically-secure-random-number-on-windows-without-using-cryptoapi/
@@ -749,7 +854,7 @@
static int
writeRandomBytes_RtlGenRandom(void * target, size_t count) {
int success = 0; /* full count bytes written? */
- const HMODULE advapi32 = LoadLibrary("ADVAPI32.DLL");
+ const HMODULE advapi32 = _Expat_LoadLibrary(TEXT("ADVAPI32.DLL"));
if (advapi32) {
const RTLGENRANDOM_FUNC RtlGenRandom
@@ -768,6 +873,8 @@
#endif /* _WIN32 */
+#if ! defined(HAVE_ARC4RANDOM_BUF) && ! defined(HAVE_ARC4RANDOM)
+
static unsigned long
gather_time_entropy(void)
{
@@ -780,16 +887,20 @@
int gettimeofday_res;
gettimeofday_res = gettimeofday(&tv, NULL);
+
+#if defined(NDEBUG)
+ (void)gettimeofday_res;
+#else
assert (gettimeofday_res == 0);
+#endif /* defined(NDEBUG) */
/* Microseconds time is <20 bits entropy */
return tv.tv_usec;
#endif
}
-#if defined(HAVE_ARC4RANDOM_BUF) && defined(HAVE_LIBBSD)
-# include <bsd/stdlib.h>
-#endif
+#endif /* ! defined(HAVE_ARC4RANDOM_BUF) && ! defined(HAVE_ARC4RANDOM) */
+
static unsigned long
ENTROPY_DEBUG(const char * label, unsigned long entropy) {
@@ -808,10 +919,12 @@
{
unsigned long entropy;
(void)parser;
-#if defined(HAVE_ARC4RANDOM_BUF) || defined(__CloudABI__)
- (void)gather_time_entropy;
+#if defined(HAVE_ARC4RANDOM_BUF)
arc4random_buf(&entropy, sizeof(entropy));
return ENTROPY_DEBUG("arc4random_buf", entropy);
+#elif defined(HAVE_ARC4RANDOM)
+ writeRandomBytes_arc4random((void *)&entropy, sizeof(entropy));
+ return ENTROPY_DEBUG("arc4random", entropy);
#else
/* Try high quality providers first .. */
#ifdef _WIN32
@@ -819,10 +932,15 @@
return ENTROPY_DEBUG("RtlGenRandom", entropy);
}
#elif defined(HAVE_GETRANDOM) || defined(HAVE_SYSCALL_GETRANDOM)
- if (writeRandomBytes_getrandom((void *)&entropy, sizeof(entropy))) {
+ if (writeRandomBytes_getrandom_nonblock((void *)&entropy, sizeof(entropy))) {
return ENTROPY_DEBUG("getrandom", entropy);
}
#endif
+#if ! defined(_WIN32) && defined(XML_DEV_URANDOM)
+ if (writeRandomBytes_dev_urandom((void *)&entropy, sizeof(entropy))) {
+ return ENTROPY_DEBUG("/dev/urandom", entropy);
+ }
+#endif /* ! defined(_WIN32) && defined(XML_DEV_URANDOM) */
/* .. and self-made low quality for backup: */
/* Process ID is 0 bits entropy if attacker has local access */
@@ -833,7 +951,7 @@
return ENTROPY_DEBUG("fallback(4)", entropy * 2147483647);
} else {
return ENTROPY_DEBUG("fallback(8)",
- entropy * (unsigned long)2305843009213693951);
+ entropy * (unsigned long)2305843009213693951ULL);
}
#endif
}
@@ -962,6 +1080,8 @@
nsAttsVersion = 0;
nsAttsPower = 0;
+ protocolEncodingName = NULL;
+
poolInit(&tempPool, &(parser->m_mem));
poolInit(&temp2Pool, &(parser->m_mem));
parserInit(parser, encodingName);
@@ -988,9 +1108,9 @@
{
processor = prologInitProcessor;
XmlPrologStateInit(&prologState);
- protocolEncodingName = (encodingName != NULL
- ? poolCopyString(&tempPool, encodingName)
- : NULL);
+ if (encodingName != NULL) {
+ protocolEncodingName = copyString(encodingName, &(parser->m_mem));
+ }
curBase = NULL;
XmlInitEncoding(&initEncoding, &encoding, 0);
userData = NULL;
@@ -1103,6 +1223,8 @@
unknownEncodingRelease(unknownEncodingData);
poolClear(&tempPool);
poolClear(&temp2Pool);
+ FREE((void *)protocolEncodingName);
+ protocolEncodingName = NULL;
parserInit(parser, encodingName);
dtdReset(_dtd, &parser->m_mem);
return XML_TRUE;
@@ -1119,10 +1241,16 @@
*/
if (ps_parsing == XML_PARSING || ps_parsing == XML_SUSPENDED)
return XML_STATUS_ERROR;
+
+ /* Get rid of any previous encoding name */
+ FREE((void *)protocolEncodingName);
+
if (encodingName == NULL)
+ /* No new encoding name */
protocolEncodingName = NULL;
else {
- protocolEncodingName = poolCopyString(&tempPool, encodingName);
+ /* Copy the new encoding name into allocated memory */
+ protocolEncodingName = copyString(encodingName, &(parser->m_mem));
if (!protocolEncodingName)
return XML_STATUS_ERROR;
}
@@ -1357,6 +1485,7 @@
destroyBindings(inheritedBindings, parser);
poolDestroy(&tempPool);
poolDestroy(&temp2Pool);
+ FREE((void *)protocolEncodingName);
#ifdef XML_DTD
/* external parameter entity parsers share the DTD structure
parser->m_dtd with the root parser, so we must not destroy it
@@ -1748,7 +1877,8 @@
XML_Parse(XML_Parser parser, const char *s, int len, int isFinal)
{
if ((parser == NULL) || (len < 0) || ((s == NULL) && (len != 0))) {
- errorCode = XML_ERROR_INVALID_ARGUMENT;
+ if (parser != NULL)
+ parser->m_errorCode = XML_ERROR_INVALID_ARGUMENT;
return XML_STATUS_ERROR;
}
switch (ps_parsing) {
@@ -1783,9 +1913,22 @@
if (errorCode == XML_ERROR_NONE) {
switch (ps_parsing) {
case XML_SUSPENDED:
+ /* It is hard to be certain, but it seems that this case
+ * cannot occur. This code is cleaning up a previous parse
+ * with no new data (since len == 0). Changing the parsing
+ * state requires getting to execute a handler function, and
+ * there doesn't seem to be an opportunity for that while in
+ * this circumstance.
+ *
+ * Given the uncertainty, we retain the code but exclude it
+ * from coverage tests.
+ *
+ * LCOV_EXCL_START
+ */
XmlUpdatePosition(encoding, positionPtr, bufferPtr, &position);
positionPtr = bufferPtr;
return XML_STATUS_SUSPENDED;
+ /* LCOV_EXCL_STOP */
case XML_INITIALIZED:
case XML_PARSING:
ps_parsing = XML_FINISHED;
@@ -2974,9 +3117,17 @@
return XML_ERROR_NO_MEMORY;
break;
default:
+ /* All of the tokens produced by XmlContentTok() have their own
+ * explicit cases, so this default is not strictly necessary.
+ * However it is a useful safety net, so we retain the code and
+ * simply exclude it from the coverage tests.
+ *
+ * LCOV_EXCL_START
+ */
if (defaultHandler)
reportDefault(parser, enc, s, next);
break;
+ /* LCOV_EXCL_STOP */
}
*eventPP = s = next;
switch (ps_parsing) {
@@ -3067,13 +3218,17 @@
#endif
attsSize = n + nDefaultAtts + INIT_ATTS_SIZE;
temp = (ATTRIBUTE *)REALLOC((void *)atts, attsSize * sizeof(ATTRIBUTE));
- if (temp == NULL)
+ if (temp == NULL) {
+ attsSize = oldAttsSize;
return XML_ERROR_NO_MEMORY;
+ }
atts = temp;
#ifdef XML_ATTR_INFO
temp2 = (XML_AttrInfo *)REALLOC((void *)attInfo, attsSize * sizeof(XML_AttrInfo));
- if (temp2 == NULL)
+ if (temp2 == NULL) {
+ attsSize = oldAttsSize;
return XML_ERROR_NO_MEMORY;
+ }
attInfo = temp2;
#endif
if (n > oldAttsSize)
@@ -3210,6 +3365,7 @@
int j; /* hash table index */
unsigned long version = nsAttsVersion;
int nsAttsSize = (int)1 << nsAttsPower;
+ unsigned char oldNsAttsPower = nsAttsPower;
/* size of hash table must be at least 2 * (# of prefixed attributes) */
if ((nPrefixes << 1) >> nsAttsPower) { /* true for nsAttsPower = 0 */
NS_ATT *temp;
@@ -3219,8 +3375,11 @@
nsAttsPower = 3;
nsAttsSize = (int)1 << nsAttsPower;
temp = (NS_ATT *)REALLOC(nsAtts, nsAttsSize * sizeof(NS_ATT));
- if (!temp)
+ if (!temp) {
+ /* Restore actual size of memory in nsAtts */
+ nsAttsPower = oldNsAttsPower;
return XML_ERROR_NO_MEMORY;
+ }
nsAtts = temp;
version = 0; /* force re-initialization of nsAtts hash table */
}
@@ -3247,8 +3406,23 @@
((XML_Char *)s)[-1] = 0; /* clear flag */
id = (ATTRIBUTE_ID *)lookup(parser, &dtd->attributeIds, s, 0);
- if (!id || !id->prefix)
- return XML_ERROR_NO_MEMORY;
+ if (!id || !id->prefix) {
+ /* This code is walking through the appAtts array, dealing
+ * with (in this case) a prefixed attribute name. To be in
+ * the array, the attribute must have already been bound, so
+ * has to have passed through the hash table lookup once
+ * already. That implies that an entry for it already
+ * exists, so the lookup above will return a pointer to
+ * already allocated memory. There is no opportunaity for
+ * the allocator to fail, so the condition above cannot be
+ * fulfilled.
+ *
+ * Since it is difficult to be certain that the above
+ * analysis is complete, we retain the test and merely
+ * remove the code from coverage tests.
+ */
+ return XML_ERROR_NO_MEMORY; /* LCOV_EXCL_LINE */
+ }
b = id->prefix->binding;
if (!b)
return XML_ERROR_UNBOUND_PREFIX;
@@ -3625,8 +3799,16 @@
}
return XML_ERROR_UNCLOSED_CDATA_SECTION;
default:
+ /* Every token returned by XmlCdataSectionTok() has its own
+ * explicit case, so this default case will never be executed.
+ * We retain it as a safety net and exclude it from the coverage
+ * statistics.
+ *
+ * LCOV_EXCL_START
+ */
*eventPP = next;
return XML_ERROR_UNEXPECTED_STATE;
+ /* LCOV_EXCL_STOP */
}
*eventPP = s = next;
@@ -3686,8 +3868,20 @@
eventEndPP = &eventEndPtr;
}
else {
+ /* It's not entirely clear, but it seems the following two lines
+ * of code cannot be executed. The only occasions on which 'enc'
+ * is not 'parser->m_encoding' are when this function is called
+ * from the internal entity processing, and IGNORE sections are an
+ * error in internal entities.
+ *
+ * Since it really isn't clear that this is true, we keep the code
+ * and just remove it from our coverage tests.
+ *
+ * LCOV_EXCL_START
+ */
eventPP = &(openInternalEntities->internalEventPtr);
eventEndPP = &(openInternalEntities->internalEventEndPtr);
+ /* LCOV_EXCL_STOP */
}
*eventPP = s;
*startPtr = NULL;
@@ -3720,8 +3914,16 @@
}
return XML_ERROR_SYNTAX; /* XML_ERROR_UNCLOSED_IGNORE_SECTION */
default:
+ /* All of the tokens that XmlIgnoreSectionTok() returns have
+ * explicit cases to handle them, so this default case is never
+ * executed. We keep it as a safety net anyway, and remove it
+ * from our test coverage statistics.
+ *
+ * LCOV_EXCL_START
+ */
*eventPP = next;
return XML_ERROR_UNEXPECTED_STATE;
+ /* LCOV_EXCL_STOP */
}
/* not reached */
}
@@ -3734,6 +3936,7 @@
const char *s;
#ifdef XML_UNICODE
char encodingBuf[128];
+ /* See comments abount `protoclEncodingName` in parserInit() */
if (!protocolEncodingName)
s = NULL;
else {
@@ -3817,7 +4020,14 @@
reportDefault(parser, encoding, s, next);
if (protocolEncodingName == NULL) {
if (newEncoding) {
- if (newEncoding->minBytesPerChar != encoding->minBytesPerChar) {
+ /* Check that the specified encoding does not conflict with what
+ * the parser has already deduced. Do we have the same number
+ * of bytes in the smallest representation of a character? If
+ * this is UTF-16, is it the same endianness?
+ */
+ if (newEncoding->minBytesPerChar != encoding->minBytesPerChar
+ || (newEncoding->minBytesPerChar == 2 &&
+ newEncoding != encoding)) {
eventPtr = encodingName;
return XML_ERROR_INCORRECT_ENCODING;
}
@@ -3962,15 +4172,14 @@
result = processXmlDecl(parser, 0, start, next);
if (result != XML_ERROR_NONE)
return result;
- switch (ps_parsing) {
- case XML_SUSPENDED:
- *nextPtr = next;
- return XML_ERROR_NONE;
- case XML_FINISHED:
+ /* At this point, ps_parsing cannot be XML_SUSPENDED. For that
+ * to happen, a parameter entity parsing handler must have
+ * attempted to suspend the parser, which fails and raises an
+ * error. The parser can be aborted, but can't be suspended.
+ */
+ if (ps_parsing == XML_FINISHED)
return XML_ERROR_ABORTED;
- default:
- *nextPtr = next;
- }
+ *nextPtr = next;
/* stop scanning for text declaration - we found one */
processor = entityValueProcessor;
return entityValueProcessor(parser, next, end, nextPtr);
@@ -4293,8 +4502,14 @@
&dtd->paramEntities,
externalSubsetName,
sizeof(ENTITY));
- if (!entity)
- return XML_ERROR_NO_MEMORY;
+ if (!entity) {
+ /* The external subset name "#" will have already been
+ * inserted into the hash table at the start of the
+ * external entity parsing, so no allocation will happen
+ * and lookup() cannot fail.
+ */
+ return XML_ERROR_NO_MEMORY; /* LCOV_EXCL_LINE */
+ }
if (useForeignDTD)
entity->base = curBase;
dtd->paramEntityRead = XML_FALSE;
@@ -4773,8 +4988,10 @@
if (prologState.level >= groupSize) {
if (groupSize) {
char *temp = (char *)REALLOC(groupConnector, groupSize *= 2);
- if (temp == NULL)
+ if (temp == NULL) {
+ groupSize /= 2;
return XML_ERROR_NO_MEMORY;
+ }
groupConnector = temp;
if (dtd->scaffIndex) {
int *temp = (int *)REALLOC(dtd->scaffIndex,
@@ -4786,8 +5003,10 @@
}
else {
groupConnector = (char *)MALLOC(groupSize = 32);
- if (!groupConnector)
+ if (!groupConnector) {
+ groupSize = 0;
return XML_ERROR_NO_MEMORY;
+ }
}
}
groupConnector[prologState.level] = 0;
@@ -4850,8 +5069,29 @@
: !dtd->hasParamEntityRefs)) {
if (!entity)
return XML_ERROR_UNDEFINED_ENTITY;
- else if (!entity->is_internal)
- return XML_ERROR_ENTITY_DECLARED_IN_PE;
+ else if (!entity->is_internal) {
+ /* It's hard to exhaustively search the code to be sure,
+ * but there doesn't seem to be a way of executing the
+ * following line. There are two cases:
+ *
+ * If 'standalone' is false, the DTD must have no
+ * parameter entities or we wouldn't have passed the outer
+ * 'if' statement. That measn the only entity in the hash
+ * table is the external subset name "#" which cannot be
+ * given as a parameter entity name in XML syntax, so the
+ * lookup must have returned NULL and we don't even reach
+ * the test for an internal entity.
+ *
+ * If 'standalone' is true, it does not seem to be
+ * possible to create entities taking this code path that
+ * are not internal entities, so fail the test above.
+ *
+ * Because this analysis is very uncertain, the code is
+ * being left in place and merely removed from the
+ * coverage test statistics.
+ */
+ return XML_ERROR_ENTITY_DECLARED_IN_PE; /* LCOV_EXCL_LINE */
+ }
}
else if (!entity) {
dtd->keepProcessing = dtd->standalone;
@@ -5323,11 +5563,15 @@
&& (poolLength(pool) == 0 || poolLastChar(pool) == 0x20))
break;
n = XmlEncode(n, (ICHAR *)buf);
- if (!n) {
- if (enc == encoding)
- eventPtr = ptr;
- return XML_ERROR_BAD_CHAR_REF;
- }
+ /* The XmlEncode() functions can never return 0 here. That
+ * error return happens if the code point passed in is either
+ * negative or greater than or equal to 0x110000. The
+ * XmlCharRefNumber() functions will all return a number
+ * strictly less than 0x110000 or a negative value if an error
+ * occurred. The negative value is intercepted above, so
+ * XmlEncode() is never passed a value it might return an
+ * error for.
+ */
for (i = 0; i < n; i++) {
if (!poolAppendChar(pool, buf[i]))
return XML_ERROR_NO_MEMORY;
@@ -5401,8 +5645,26 @@
break;
}
if (entity->open) {
- if (enc == encoding)
- eventPtr = ptr;
+ if (enc == encoding) {
+ /* It does not appear that this line can be executed.
+ *
+ * The "if (entity->open)" check catches recursive entity
+ * definitions. In order to be called with an open
+ * entity, it must have gone through this code before and
+ * been through the recursive call to
+ * appendAttributeValue() some lines below. That call
+ * sets the local encoding ("enc") to the parser's
+ * internal encoding (internal_utf8 or internal_utf16),
+ * which can never be the same as the principle encoding.
+ * It doesn't appear there is another code path that gets
+ * here with entity->open being TRUE.
+ *
+ * Since it is not certain that this logic is watertight,
+ * we keep the line and merely exclude it from coverage
+ * tests.
+ */
+ eventPtr = ptr; /* LCOV_EXCL_LINE */
+ }
return XML_ERROR_RECURSIVE_ENTITY_REF;
}
if (entity->notation) {
@@ -5429,9 +5691,21 @@
}
break;
default:
+ /* The only token returned by XmlAttributeValueTok() that does
+ * not have an explicit case here is XML_TOK_PARTIAL_CHAR.
+ * Getting that would require an entity name to contain an
+ * incomplete XML character (e.g. \xE2\x82); however previous
+ * tokenisers will have already recognised and rejected such
+ * names before XmlAttributeValueTok() gets a look-in. This
+ * default case should be retained as a safety net, but the code
+ * excluded from coverage tests.
+ *
+ * LCOV_EXCL_START
+ */
if (enc == encoding)
eventPtr = ptr;
return XML_ERROR_UNEXPECTED_STATE;
+ /* LCOV_EXCL_STOP */
}
ptr = next;
}
@@ -5564,12 +5838,15 @@
goto endEntityValue;
}
n = XmlEncode(n, (ICHAR *)buf);
- if (!n) {
- if (enc == encoding)
- eventPtr = entityTextPtr;
- result = XML_ERROR_BAD_CHAR_REF;
- goto endEntityValue;
- }
+ /* The XmlEncode() functions can never return 0 here. That
+ * error return happens if the code point passed in is either
+ * negative or greater than or equal to 0x110000. The
+ * XmlCharRefNumber() functions will all return a number
+ * strictly less than 0x110000 or a negative value if an error
+ * occurred. The negative value is intercepted above, so
+ * XmlEncode() is never passed a value it might return an
+ * error for.
+ */
for (i = 0; i < n; i++) {
if (pool->end == pool->ptr && !poolGrow(pool)) {
result = XML_ERROR_NO_MEMORY;
@@ -5590,10 +5867,18 @@
result = XML_ERROR_INVALID_TOKEN;
goto endEntityValue;
default:
+ /* This default case should be unnecessary -- all the tokens
+ * that XmlEntityValueTok() can return have their own explicit
+ * cases -- but should be retained for safety. We do however
+ * exclude it from the coverage statistics.
+ *
+ * LCOV_EXCL_START
+ */
if (enc == encoding)
eventPtr = entityTextPtr;
result = XML_ERROR_UNEXPECTED_STATE;
goto endEntityValue;
+ /* LCOV_EXCL_STOP */
}
entityTextPtr = next;
}
@@ -5691,8 +5976,25 @@
eventEndPP = &eventEndPtr;
}
else {
+ /* To get here, two things must be true; the parser must be
+ * using a character encoding that is not the same as the
+ * encoding passed in, and the encoding passed in must need
+ * conversion to the internal format (UTF-8 unless XML_UNICODE
+ * is defined). The only occasions on which the encoding passed
+ * in is not the same as the parser's encoding are when it is
+ * the internal encoding (e.g. a previously defined parameter
+ * entity, already converted to internal format). This by
+ * definition doesn't need conversion, so the whole branch never
+ * gets executed.
+ *
+ * For safety's sake we don't delete these lines and merely
+ * exclude them from coverage statistics.
+ *
+ * LCOV_EXCL_START
+ */
eventPP = &(openInternalEntities->internalEventPtr);
eventEndPP = &(openInternalEntities->internalEventEndPtr);
+ /* LCOV_EXCL_STOP */
}
do {
ICHAR *dataPtr = (ICHAR *)dataBuf;
@@ -5861,9 +6163,30 @@
len = dtd->defaultPrefix.binding->uriLen;
if (namespaceSeparator)
len--;
- for (i = 0; i < len; i++)
- if (!poolAppendChar(&tempPool, dtd->defaultPrefix.binding->uri[i]))
- return NULL;
+ for (i = 0; i < len; i++) {
+ if (!poolAppendChar(&tempPool, dtd->defaultPrefix.binding->uri[i])) {
+ /* Because of memory caching, I don't believe this line can be
+ * executed.
+ *
+ * This is part of a loop copying the default prefix binding
+ * URI into the parser's temporary string pool. Previously,
+ * that URI was copied into the same string pool, with a
+ * terminating NUL character, as part of setContext(). When
+ * the pool was cleared, that leaves a block definitely big
+ * enough to hold the URI on the free block list of the pool.
+ * The URI copy in getContext() therefore cannot run out of
+ * memory.
+ *
+ * If the pool is used between the setContext() and
+ * getContext() calls, the worst it can do is leave a bigger
+ * block on the front of the free list. Given that this is
+ * all somewhat inobvious and program logic can be changed, we
+ * don't delete the line but we do exclude it from the test
+ * coverage statistics.
+ */
+ return NULL; /* LCOV_EXCL_LINE */
+ }
+ }
needSep = XML_TRUE;
}
@@ -5875,8 +6198,15 @@
PREFIX *prefix = (PREFIX *)hashTableIterNext(&iter);
if (!prefix)
break;
- if (!prefix->binding)
- continue;
+ if (!prefix->binding) {
+ /* This test appears to be (justifiable) paranoia. There does
+ * not seem to be a way of injecting a prefix without a binding
+ * that doesn't get errored long before this function is called.
+ * The test should remain for safety's sake, so we instead
+ * exclude the following line from the coverage statistics.
+ */
+ continue; /* LCOV_EXCL_LINE */
+ }
if (needSep && !poolAppendChar(&tempPool, CONTEXT_SEP))
return NULL;
for (s = prefix->name; *s; s++)
@@ -6547,8 +6877,20 @@
static const XML_Char *
poolCopyStringN(STRING_POOL *pool, const XML_Char *s, int n)
{
- if (!pool->ptr && !poolGrow(pool))
- return NULL;
+ if (!pool->ptr && !poolGrow(pool)) {
+ /* The following line is unreachable given the current usage of
+ * poolCopyStringN(). Currently it is called from exactly one
+ * place to copy the text of a simple general entity. By that
+ * point, the name of the entity is already stored in the pool, so
+ * pool->ptr cannot be NULL.
+ *
+ * If poolCopyStringN() is used elsewhere as it well might be,
+ * this line may well become executable again. Regardless, this
+ * sort of check shouldn't be removed lightly, so we just exclude
+ * it from the coverage statistics.
+ */
+ return NULL; /* LCOV_EXCL_LINE */
+ }
for (; n > 0; --n, s++) {
if (!poolAppendChar(pool, *s))
return NULL;
@@ -6641,8 +6983,19 @@
int blockSize = (int)((unsigned)(pool->end - pool->start)*2U);
size_t bytesToAllocate;
- if (blockSize < 0)
- return XML_FALSE;
+ // NOTE: Needs to be calculated prior to calling `realloc`
+ // to avoid dangling pointers:
+ const ptrdiff_t offsetInsideBlock = pool->ptr - pool->start;
+
+ if (blockSize < 0) {
+ /* This condition traps a situation where either more than
+ * INT_MAX/2 bytes have already been allocated. This isn't
+ * readily testable, since it is unlikely that an average
+ * machine will have that much memory, so we exclude it from the
+ * coverage statistics.
+ */
+ return XML_FALSE; /* LCOV_EXCL_LINE */
+ }
bytesToAllocate = poolBytesToAllocateFor(blockSize);
if (bytesToAllocate == 0)
@@ -6654,7 +7007,7 @@
return XML_FALSE;
pool->blocks = temp;
pool->blocks->size = blockSize;
- pool->ptr = pool->blocks->s + (pool->ptr - pool->start);
+ pool->ptr = pool->blocks->s + offsetInsideBlock;
pool->start = pool->blocks->s;
pool->end = pool->start + blockSize;
}
@@ -6663,8 +7016,18 @@
int blockSize = (int)(pool->end - pool->start);
size_t bytesToAllocate;
- if (blockSize < 0)
- return XML_FALSE;
+ if (blockSize < 0) {
+ /* This condition traps a situation where either more than
+ * INT_MAX bytes have already been allocated (which is prevented
+ * by various pieces of program logic, not least this one, never
+ * mind the unlikelihood of actually having that much memory) or
+ * the pool control fields have been corrupted (which could
+ * conceivably happen in an extremely buggy user handler
+ * function). Either way it isn't readily testable, so we
+ * exclude it from the coverage statistics.
+ */
+ return XML_FALSE; /* LCOV_EXCL_LINE */
+ }
if (blockSize < INIT_BLOCK_SIZE)
blockSize = INIT_BLOCK_SIZE;
@@ -6827,3 +7190,26 @@
}
return ret;
}
+
+static XML_Char *
+copyString(const XML_Char *s,
+ const XML_Memory_Handling_Suite *memsuite)
+{
+ int charsRequired = 0;
+ XML_Char *result;
+
+ /* First determine how long the string is */
+ while (s[charsRequired] != 0) {
+ charsRequired++;
+ }
+ /* Include the terminator */
+ charsRequired++;
+
+ /* Now allocate space for the copy */
+ result = memsuite->malloc_fcn(charsRequired * sizeof(XML_Char));
+ if (result == NULL)
+ return NULL;
+ /* Copy the original into place */
+ memcpy(result, s, charsRequired * sizeof(XML_Char));
+ return result;
+}