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author | Jonathan Wakely <jwakely@redhat.com> | 2019-01-07 14:58:44 +0000 |
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committer | Jonathan Wakely <redi@gcc.gnu.org> | 2019-01-07 14:58:44 +0000 |
commit | e002afaa8e01395110c77de18bb7e0fa030ba019 (patch) | |
tree | 203a73ef36a0dbf4ceb00a25c30b1bcfdafabcb2 /libstdc++-v3 | |
parent | a58fe3c5ca1f0101c4af7f0c5b860cc4d49cd4cb (diff) | |
download | gcc-e002afaa8e01395110c77de18bb7e0fa030ba019.zip gcc-e002afaa8e01395110c77de18bb7e0fa030ba019.tar.gz gcc-e002afaa8e01395110c77de18bb7e0fa030ba019.tar.bz2 |
PR libstdc++/87787 avoid undefined null args to memcpy and memmove
The C++ char_traits and ctype APIs do not disallow null pointer
arguments, so we need explicit checks to ensure we don't forward null
pointers to memcpy or memmove.
PR libstdc++/87787
* include/bits/char_traits.h (char_traits::move): Do not pass null
pointers to memmove.
* include/bits/locale_facets.h
(ctype<char>::widen(const char*, const char*, char*)): Do not
pass null pointers to memcpy.
(ctype<char>::narrow(const char*, const char*, char, char*)):
Likewise.
(ctype<char>::do_widen(const char*, const char*, char*)):
Likewise.
(ctype<char>::do_narrow(const char*, const char*, char, char*)):
Likewise.
From-SVN: r267651
Diffstat (limited to 'libstdc++-v3')
-rw-r--r-- | libstdc++-v3/ChangeLog | 13 | ||||
-rw-r--r-- | libstdc++-v3/include/bits/char_traits.h | 2 | ||||
-rw-r--r-- | libstdc++-v3/include/bits/locale_facets.h | 12 |
3 files changed, 23 insertions, 4 deletions
diff --git a/libstdc++-v3/ChangeLog b/libstdc++-v3/ChangeLog index a2c01ad..0babce9 100644 --- a/libstdc++-v3/ChangeLog +++ b/libstdc++-v3/ChangeLog @@ -1,5 +1,18 @@ 2019-01-07 Jonathan Wakely <jwakely@redhat.com> + PR libstdc++/87787 + * include/bits/char_traits.h (char_traits::move): Do not pass null + pointers to memmove. + * include/bits/locale_facets.h + (ctype<char>::widen(const char*, const char*, char*)): Do not + pass null pointers to memcpy. + (ctype<char>::narrow(const char*, const char*, char, char*)): + Likewise. + (ctype<char>::do_widen(const char*, const char*, char*)): + Likewise. + (ctype<char>::do_narrow(const char*, const char*, char, char*)): + Likewise. + * doc/xml/manual/spine.xml: Update copyright years. * doc/xml/manual/status_cxx2017.xml: Adjust note about -lstdc++fs. * doc/xml/manual/using.xml: Remove requirement to link with -lstdc++fs diff --git a/libstdc++-v3/include/bits/char_traits.h b/libstdc++-v3/include/bits/char_traits.h index a2ba5da..06e04ce 100644 --- a/libstdc++-v3/include/bits/char_traits.h +++ b/libstdc++-v3/include/bits/char_traits.h @@ -183,6 +183,8 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION char_traits<_CharT>:: move(char_type* __s1, const char_type* __s2, std::size_t __n) { + if (__n == 0) + return __s1; return static_cast<_CharT*>(__builtin_memmove(__s1, __s2, __n * sizeof(char_type))); } diff --git a/libstdc++-v3/include/bits/locale_facets.h b/libstdc++-v3/include/bits/locale_facets.h index 33cff65..66ac9c0 100644 --- a/libstdc++-v3/include/bits/locale_facets.h +++ b/libstdc++-v3/include/bits/locale_facets.h @@ -896,7 +896,8 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION { if (_M_widen_ok == 1) { - __builtin_memcpy(__to, __lo, __hi - __lo); + if (__builtin_expect(__hi != __lo, true)) + __builtin_memcpy(__to, __lo, __hi - __lo); return __hi; } if (!_M_widen_ok) @@ -961,7 +962,8 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION { if (__builtin_expect(_M_narrow_ok == 1, true)) { - __builtin_memcpy(__to, __lo, __hi - __lo); + if (__builtin_expect(__hi != __lo, true)) + __builtin_memcpy(__to, __lo, __hi - __lo); return __hi; } if (!_M_narrow_ok) @@ -1100,7 +1102,8 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION virtual const char* do_widen(const char* __lo, const char* __hi, char_type* __to) const { - __builtin_memcpy(__to, __lo, __hi - __lo); + if (__builtin_expect(__hi != __lo, true)) + __builtin_memcpy(__to, __lo, __hi - __lo); return __hi; } @@ -1153,7 +1156,8 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION do_narrow(const char_type* __lo, const char_type* __hi, char __dfault __attribute__((__unused__)), char* __to) const { - __builtin_memcpy(__to, __lo, __hi - __lo); + if (__builtin_expect(__hi != __lo, true)) + __builtin_memcpy(__to, __lo, __hi - __lo); return __hi; } |