From b612db5b14728214ca09355af5d1490df2fa1c2f Mon Sep 17 00:00:00 2001 From: Corinna Vinschen Date: Thu, 11 Aug 2022 19:27:48 +0200 Subject: newlocale: fix crash when trying to write to __C_locale This simple testcase: locale_t st = newlocale(LC_ALL_MASK, "C", (locale_t)0); locale_t st2 = newlocale(LC_CTYPE_MASK, "en_US.UTF-8", st); is sufficient to reproduce a crash in _newlocale_r. After the first call to newlocale, `st' points to __C_locale, which is const. When using `st' as locale base in the second call, _newlocale_r tries to set pointers inside base to NULL. This is bad if base is __C_locale, obviously. Add a test to avoid trying to overwrite pointer values inside base if base is __C_locale. Signed-off-by: Corinna Vinschen --- newlib/libc/locale/newlocale.c | 3 ++- winsup/cygwin/release/3.3.6 | 3 +++ 2 files changed, 5 insertions(+), 1 deletion(-) diff --git a/newlib/libc/locale/newlocale.c b/newlib/libc/locale/newlocale.c index 0789d5fd..08f29db 100644 --- a/newlib/libc/locale/newlocale.c +++ b/newlib/libc/locale/newlocale.c @@ -188,7 +188,8 @@ _newlocale_r (struct _reent *p, int category_mask, const char *locale, if (tmp_locale.lc_cat[i].buf == (const void *) -1) { tmp_locale.lc_cat[i].buf = base->lc_cat[i].buf; - base->lc_cat[i].ptr = base->lc_cat[i].buf = NULL; + if (base != __get_C_locale ()) + base->lc_cat[i].ptr = base->lc_cat[i].buf = NULL; } #endif /* __HAVE_LOCALE_INFO__ */ _freelocale_r (p, base); diff --git a/winsup/cygwin/release/3.3.6 b/winsup/cygwin/release/3.3.6 index 364e0cb..1da4fa2 100644 --- a/winsup/cygwin/release/3.3.6 +++ b/winsup/cygwin/release/3.3.6 @@ -39,3 +39,6 @@ Bug Fixes - Fix a path handling bug that could cause a non-existing file to be treated as the current directory. Addresses: https://cygwin.com/pipermail/cygwin/2022-August/252030.html + +- Fix a crash in newlocale. + Addresses: https://cygwin.com/pipermail/cygwin/2022-August/252043.html -- cgit v1.1