[PATCH 4/4] ctype: Fallback initialization of TLS using relocations (bug 19341, bug 32483)
Florian Weimer
fweimer@redhat.com
Thu Dec 19 20:58:27 GMT 2024
This ensures that the ctype data pointers in TLS are valid
in secondary namespaces even without initialization via
__ctype_init.
---
ctype/Makefile | 16 +++++++
ctype/ctype-info.c | 14 ++++--
ctype/tst-ctype-tls-dlmopen.c | 2 +
ctype/tst-ctype-tls-dlopen-static.c | 2 +
ctype/tst-ctype-tls-mod.c | 37 ++++++++++++++++
ctype/tst-ctype-tls-skeleton.c | 67 +++++++++++++++++++++++++++++
6 files changed, 135 insertions(+), 3 deletions(-)
create mode 100644 ctype/tst-ctype-tls-dlmopen.c
create mode 100644 ctype/tst-ctype-tls-dlopen-static.c
create mode 100644 ctype/tst-ctype-tls-mod.c
create mode 100644 ctype/tst-ctype-tls-skeleton.c
diff --git a/ctype/Makefile b/ctype/Makefile
index 3e09938bd1..df07d42095 100644
--- a/ctype/Makefile
+++ b/ctype/Makefile
@@ -36,6 +36,22 @@ aux := ctype-info
tests := \
test_ctype \
+ tst-ctype-tls-dlmopen \
+ tst-ctype-tls-dlopen-static \
# tests
+tests-static := \
+ tst-ctype-tls-dlopen-static \
+ # tests-static
+
+modules-names := \
+ tst-ctype-tls-mod \
+ # modules-names
+
include ../Rules
+
+$(objpfx)tst-ctype-tls-dlmopen: $(shared-thread-library)
+$(objpfx)tst-ctype-tls-dlmopen.out: $(objpfx)tst-ctype-tls-mod.so
+$(objpfx)tst-ctype-tls-dlopen-static: $(static-thread-library)
+$(objpfx)tst-ctype-tls-dlopen-static.out: $(objpfx)tst-ctype-tls-mod.so
+tst-ctype-tls-dlopen-static-ENV = LD_LIBRARY_PATH=$(ld-library-path)
diff --git a/ctype/ctype-info.c b/ctype/ctype-info.c
index 94e312d91f..621bd4239c 100644
--- a/ctype/ctype-info.c
+++ b/ctype/ctype-info.c
@@ -19,9 +19,17 @@
#include <ctype.h>
#include <locale/localeinfo.h>
-__thread const uint16_t * __libc_tsd_CTYPE_B;
-__thread const int32_t * __libc_tsd_CTYPE_TOLOWER;
-__thread const int32_t * __libc_tsd_CTYPE_TOUPPER;
+/* Fallback initialization using relocations. See the _nl_C_locobj
+ initializers in locale/xlocale.c. Usually, this is overwritten by
+ __ctype_init before user code runs, but this does not happen for
+ threads in secondary namespaces. With the initializers, secondary
+ namespaces at least get locale data from the C locale. */
+__thread const uint16_t * __libc_tsd_CTYPE_B
+ = (const uint16_t *) _nl_C_LC_CTYPE_class + 128;
+__thread const int32_t * __libc_tsd_CTYPE_TOLOWER
+ = (const int32_t *) _nl_C_LC_CTYPE_tolower + 128;
+__thread const int32_t * __libc_tsd_CTYPE_TOUPPER
+ = (const int32_t *) _nl_C_LC_CTYPE_toupper + 128;
void
diff --git a/ctype/tst-ctype-tls-dlmopen.c b/ctype/tst-ctype-tls-dlmopen.c
new file mode 100644
index 0000000000..f7eeb65551
--- /dev/null
+++ b/ctype/tst-ctype-tls-dlmopen.c
@@ -0,0 +1,2 @@
+#define DO_STATIC_TEST 0
+#include "tst-ctype-tls-skeleton.c"
diff --git a/ctype/tst-ctype-tls-dlopen-static.c b/ctype/tst-ctype-tls-dlopen-static.c
new file mode 100644
index 0000000000..c2c09c362c
--- /dev/null
+++ b/ctype/tst-ctype-tls-dlopen-static.c
@@ -0,0 +1,2 @@
+#define DO_STATIC_TEST 1
+#include "tst-ctype-tls-skeleton.c"
diff --git a/ctype/tst-ctype-tls-mod.c b/ctype/tst-ctype-tls-mod.c
new file mode 100644
index 0000000000..dba689701f
--- /dev/null
+++ b/ctype/tst-ctype-tls-mod.c
@@ -0,0 +1,37 @@
+/* Wrappers for <ctype.h> macros in a secondary namespace.
+ Copyright (C) 2024 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ The GNU C Library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, see
+ <https://www.gnu.org/licenses/>. */
+
+#include <ctype.h>
+
+int
+my_isalpha (int ch)
+{
+ return isalpha (ch);
+}
+
+int
+my_toupper (int ch)
+{
+ return toupper (ch);
+}
+
+int
+my_tolower (int ch)
+{
+ return tolower (ch);
+}
diff --git a/ctype/tst-ctype-tls-skeleton.c b/ctype/tst-ctype-tls-skeleton.c
new file mode 100644
index 0000000000..421c984f70
--- /dev/null
+++ b/ctype/tst-ctype-tls-skeleton.c
@@ -0,0 +1,67 @@
+/* Test that <ctype.h> in a secondary namespace works.
+ Copyright (C) 2024 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ The GNU C Library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, see
+ <https://www.gnu.org/licenses/>. */
+
+/* Before this file is included, define DO_STATIC_TEST to 0 or 1.
+ With 0, dlmopen is used for the test. With 1, dlopen is used. */
+
+#include <stddef.h>
+#include <stdlib.h>
+#include <support/check.h>
+#include <support/support.h>
+#include <support/xdlfcn.h>
+#include <support/xthread.h>
+
+static int (*my_isalpha) (int);
+static int (*my_toupper) (int);
+static int (*my_tolower) (int);
+
+static void *
+checks (void *ignore)
+{
+ TEST_VERIFY (my_isalpha ('a'));
+ TEST_VERIFY (!my_isalpha ('0'));
+ TEST_COMPARE (my_toupper ('a'), 'A');
+ TEST_COMPARE (my_toupper ('A'), 'A');
+ TEST_COMPARE (my_tolower ('a'), 'a');
+ TEST_COMPARE (my_tolower ('A'), 'a');
+ return NULL;
+}
+
+static int
+do_test (void)
+{
+ char *dso = xasprintf ("%s/ctype/tst-ctype-tls-mod.so", support_objdir_root);
+#if DO_STATIC_TEST
+ void *handle = xdlopen (dso, RTLD_LAZY);
+#else
+ void *handle = xdlmopen (LM_ID_NEWLM, dso, RTLD_LAZY);
+#endif
+ my_isalpha = xdlsym (handle, "my_isalpha");
+ my_toupper = xdlsym (handle, "my_toupper");
+ my_tolower = xdlsym (handle, "my_tolower");
+
+ checks (NULL);
+ xpthread_join (xpthread_create (NULL, checks, NULL));
+
+ xdlclose (handle);
+ free (dso);
+
+ return 0;
+}
+
+#include <support/test-driver.c>
--
2.47.1
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