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Created December 30, 2018 03:54
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commit 0839641503bc381d64347081b4308dd7335a26b5
Author: Stanislav Malyshev <stas@php.net>
Date: Sat Dec 29 19:51:24 2018 -0800
Fix bug #77370 - check that we do not read past buffer end when parsing multibytes
diff --git a/ext/mbstring/oniguruma/regparse.c b/ext/mbstring/oniguruma/regparse.c
index d2925f1e81..252ca18712 100644
--- a/ext/mbstring/oniguruma/regparse.c
+++ b/ext/mbstring/oniguruma/regparse.c
@@ -246,6 +246,12 @@ strdup_with_null(OnigEncoding enc, UChar* s, UChar* end)
}
#endif
+#if (defined (__GNUC__) && __GNUC__ > 2 ) && !defined(DARWIN) && !defined(__hpux) && !defined(_AIX)
+# define UNEXPECTED(condition) __builtin_expect(condition, 0)
+#else
+# define UNEXPECTED(condition) (condition)
+#endif
+
/* scan pattern methods */
#define PEND_VALUE 0
@@ -260,14 +266,17 @@ strdup_with_null(OnigEncoding enc, UChar* s, UChar* end)
c = ONIGENC_MBC_TO_CODE(enc, p, end); \
pfetch_prev = p; \
p += ONIGENC_MBC_ENC_LEN(enc, p); \
+ if(UNEXPECTED(p > end)) p = end; \
} while (0)
#define PINC_S do { \
p += ONIGENC_MBC_ENC_LEN(enc, p); \
+ if(UNEXPECTED(p > end)) p = end; \
} while (0)
#define PFETCH_S(c) do { \
c = ONIGENC_MBC_TO_CODE(enc, p, end); \
p += ONIGENC_MBC_ENC_LEN(enc, p); \
+ if(UNEXPECTED(p > end)) p = end; \
} while (0)
#define PPEEK (p < end ? ONIGENC_MBC_TO_CODE(enc, p, end) : PEND_VALUE)
diff --git a/ext/mbstring/tests/bug77370.phpt b/ext/mbstring/tests/bug77370.phpt
new file mode 100644
index 0000000000..c4d25582fe
--- /dev/null
+++ b/ext/mbstring/tests/bug77370.phpt
@@ -0,0 +1,13 @@
+--TEST--
+Bug #77370 (Buffer overflow on mb regex functions - fetch_token)
+--SKIPIF--
+<?php extension_loaded('mbstring') or die('skip mbstring not available'); ?>
+--FILE--
+<?php
+var_dump(mb_split(" \xfd",""));
+?>
+--EXPECT--
+array(1) {
+ [0]=>
+ string(0) ""
+}
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