diff options
Diffstat (limited to 'expat/lib/xmlparse.c')
| -rw-r--r-- | expat/lib/xmlparse.c | 31 |
1 files changed, 29 insertions, 2 deletions
diff --git a/expat/lib/xmlparse.c b/expat/lib/xmlparse.c index d730f41c..b47c31b0 100644 --- a/expat/lib/xmlparse.c +++ b/expat/lib/xmlparse.c @@ -3414,7 +3414,13 @@ storeAtts(XML_Parser parser, const ENCODING *enc, const char *attStr, if (nPrefixes) { int j; /* hash table index */ unsigned long version = parser->m_nsAttsVersion; - int nsAttsSize = (int)1 << parser->m_nsAttsPower; + + /* Detect and prevent invalid shift */ + if (parser->m_nsAttsPower >= sizeof(unsigned int) * 8 /* bits per byte */) { + return XML_ERROR_NO_MEMORY; + } + + unsigned int nsAttsSize = 1u << parser->m_nsAttsPower; unsigned char oldNsAttsPower = parser->m_nsAttsPower; /* size of hash table must be at least 2 * (# of prefixed attributes) */ if ((nPrefixes << 1) @@ -3425,7 +3431,28 @@ storeAtts(XML_Parser parser, const ENCODING *enc, const char *attStr, ; if (parser->m_nsAttsPower < 3) parser->m_nsAttsPower = 3; - nsAttsSize = (int)1 << parser->m_nsAttsPower; + + /* Detect and prevent invalid shift */ + if (parser->m_nsAttsPower >= sizeof(nsAttsSize) * 8 /* bits per byte */) { + /* Restore actual size of memory in m_nsAtts */ + parser->m_nsAttsPower = oldNsAttsPower; + return XML_ERROR_NO_MEMORY; + } + + nsAttsSize = 1u << parser->m_nsAttsPower; + + /* Detect and prevent integer overflow. + * The preprocessor guard addresses the "always false" warning + * from -Wtype-limits on platforms where + * sizeof(unsigned int) < sizeof(size_t), e.g. on x86_64. */ +#if UINT_MAX >= SIZE_MAX + if (nsAttsSize > (size_t)(-1) / sizeof(NS_ATT)) { + /* Restore actual size of memory in m_nsAtts */ + parser->m_nsAttsPower = oldNsAttsPower; + return XML_ERROR_NO_MEMORY; + } +#endif + temp = (NS_ATT *)REALLOC(parser, parser->m_nsAtts, nsAttsSize * sizeof(NS_ATT)); if (! temp) { |