You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
225 lines
7.3 KiB
225 lines
7.3 KiB
commit 54b12733959238204d7b0e46e69fc7f7d8890b20
|
|
Author: Florian Weimer <fweimer@redhat.com>
|
|
Date: Fri Mar 11 08:23:56 2022 +0100
|
|
|
|
nss: Protect against errno changes in function lookup (bug 28953)
|
|
|
|
dlopen may clobber errno. The nss_test_errno module uses an ELF
|
|
constructor to achieve that, but there could be internal errors
|
|
during dlopen that cause this, too. Therefore, the NSS framework
|
|
has to guard against such errno clobbers.
|
|
|
|
__nss_module_get_function is currently the only function that calls
|
|
__nss_module_load, so it is sufficient to save and restore errno
|
|
around this call.
|
|
|
|
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
|
|
(cherry picked from commit 9bdf92c79d63b42f931101bb6df87129c408b0c4)
|
|
|
|
diff --git a/nss/Makefile b/nss/Makefile
|
|
index e223243d9d62041c..716bc8f6ef5276b0 100644
|
|
--- a/nss/Makefile
|
|
+++ b/nss/Makefile
|
|
@@ -60,7 +60,8 @@ tests = test-netdb test-digits-dots tst-nss-getpwent bug17079 \
|
|
tst-nss-test1 \
|
|
tst-nss-test2 \
|
|
tst-nss-test4 \
|
|
- tst-nss-test5
|
|
+ tst-nss-test5 \
|
|
+ tst-nss-test_errno
|
|
xtests = bug-erange
|
|
|
|
tests-container = \
|
|
@@ -132,7 +133,7 @@ libnss_compat-inhibit-o = $(filter-out .os,$(object-suffixes))
|
|
ifeq ($(build-static-nss),yes)
|
|
tests-static += tst-nss-static
|
|
endif
|
|
-extra-test-objs += nss_test1.os nss_test2.os
|
|
+extra-test-objs += nss_test1.os nss_test2.os nss_test_errno.os
|
|
|
|
include ../Rules
|
|
|
|
@@ -166,19 +167,26 @@ rtld-tests-LDFLAGS += -Wl,--dynamic-list=nss_test.ver
|
|
|
|
libof-nss_test1 = extramodules
|
|
libof-nss_test2 = extramodules
|
|
+libof-nss_test_errno = extramodules
|
|
$(objpfx)/libnss_test1.so: $(objpfx)nss_test1.os $(link-libc-deps)
|
|
$(build-module)
|
|
$(objpfx)/libnss_test2.so: $(objpfx)nss_test2.os $(link-libc-deps)
|
|
$(build-module)
|
|
+$(objpfx)/libnss_test_errno.so: $(objpfx)nss_test_errno.os $(link-libc-deps)
|
|
+ $(build-module)
|
|
$(objpfx)nss_test2.os : nss_test1.c
|
|
# Use the nss_files suffix for these objects as well.
|
|
$(objpfx)/libnss_test1.so$(libnss_files.so-version): $(objpfx)/libnss_test1.so
|
|
$(make-link)
|
|
$(objpfx)/libnss_test2.so$(libnss_files.so-version): $(objpfx)/libnss_test2.so
|
|
$(make-link)
|
|
+$(objpfx)/libnss_test_errno.so$(libnss_files.so-version): \
|
|
+ $(objpfx)/libnss_test_errno.so
|
|
+ $(make-link)
|
|
$(patsubst %,$(objpfx)%.out,$(tests) $(tests-container)) : \
|
|
$(objpfx)/libnss_test1.so$(libnss_files.so-version) \
|
|
- $(objpfx)/libnss_test2.so$(libnss_files.so-version)
|
|
+ $(objpfx)/libnss_test2.so$(libnss_files.so-version) \
|
|
+ $(objpfx)/libnss_test_errno.so$(libnss_files.so-version)
|
|
|
|
ifeq (yes,$(have-thread-library))
|
|
$(objpfx)tst-cancel-getpwuid_r: $(shared-thread-library)
|
|
diff --git a/nss/nss_module.c b/nss/nss_module.c
|
|
index b28cb94a6a0aeb41..3a4a464256121e41 100644
|
|
--- a/nss/nss_module.c
|
|
+++ b/nss/nss_module.c
|
|
@@ -330,8 +330,18 @@ name_search (const void *left, const void *right)
|
|
void *
|
|
__nss_module_get_function (struct nss_module *module, const char *name)
|
|
{
|
|
+ /* A successful dlopen might clobber errno. */
|
|
+ int saved_errno = errno;
|
|
+
|
|
if (!__nss_module_load (module))
|
|
- return NULL;
|
|
+ {
|
|
+ /* Reporting module load failure is currently inaccurate. See
|
|
+ bug 22041. Not changing errno is the conservative choice. */
|
|
+ __set_errno (saved_errno);
|
|
+ return NULL;
|
|
+ }
|
|
+
|
|
+ __set_errno (saved_errno);
|
|
|
|
function_name *name_entry = bsearch (name, nss_function_name_array,
|
|
array_length (nss_function_name_array),
|
|
diff --git a/nss/nss_test_errno.c b/nss/nss_test_errno.c
|
|
new file mode 100644
|
|
index 0000000000000000..680f8a07b97fe263
|
|
--- /dev/null
|
|
+++ b/nss/nss_test_errno.c
|
|
@@ -0,0 +1,58 @@
|
|
+/* NSS service provider with errno clobber.
|
|
+ Copyright (C) 2022 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 <errno.h>
|
|
+#include <nss.h>
|
|
+#include <stdlib.h>
|
|
+
|
|
+/* Catch misnamed and functions. */
|
|
+#pragma GCC diagnostic error "-Wmissing-prototypes"
|
|
+NSS_DECLARE_MODULE_FUNCTIONS (test_errno)
|
|
+
|
|
+static void __attribute__ ((constructor))
|
|
+init (void)
|
|
+{
|
|
+ /* An arbitrary error code which is otherwise not used. */
|
|
+ errno = ELIBBAD;
|
|
+}
|
|
+
|
|
+/* Lookup functions for pwd follow that do not return any data. */
|
|
+
|
|
+/* Catch misnamed function definitions. */
|
|
+
|
|
+enum nss_status
|
|
+_nss_test_errno_setpwent (int stayopen)
|
|
+{
|
|
+ setenv ("_nss_test_errno_setpwent", "yes", 1);
|
|
+ return NSS_STATUS_SUCCESS;
|
|
+}
|
|
+
|
|
+enum nss_status
|
|
+_nss_test_errno_getpwent_r (struct passwd *result,
|
|
+ char *buffer, size_t size, int *errnop)
|
|
+{
|
|
+ setenv ("_nss_test_errno_getpwent_r", "yes", 1);
|
|
+ return NSS_STATUS_NOTFOUND;
|
|
+}
|
|
+
|
|
+enum nss_status
|
|
+_nss_test_errno_endpwent (void)
|
|
+{
|
|
+ setenv ("_nss_test_errno_endpwent", "yes", 1);
|
|
+ return NSS_STATUS_SUCCESS;
|
|
+}
|
|
diff --git a/nss/tst-nss-test_errno.c b/nss/tst-nss-test_errno.c
|
|
new file mode 100644
|
|
index 0000000000000000..d2c42dd363a38b0e
|
|
--- /dev/null
|
|
+++ b/nss/tst-nss-test_errno.c
|
|
@@ -0,0 +1,61 @@
|
|
+/* getpwent failure when dlopen clobbers errno (bug 28953).
|
|
+ Copyright (C) 2022 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 <nss.h>
|
|
+#include <support/check.h>
|
|
+#include <stdlib.h>
|
|
+#include <errno.h>
|
|
+#include <stdbool.h>
|
|
+#include <pwd.h>
|
|
+#include <string.h>
|
|
+
|
|
+static int
|
|
+do_test (void)
|
|
+{
|
|
+ __nss_configure_lookup ("passwd", "files test_errno");
|
|
+
|
|
+ errno = 0;
|
|
+ setpwent ();
|
|
+ TEST_COMPARE (errno, 0);
|
|
+
|
|
+ bool root_seen = false;
|
|
+ while (true)
|
|
+ {
|
|
+ errno = 0;
|
|
+ struct passwd *e = getpwent ();
|
|
+ if (e == NULL)
|
|
+ break;
|
|
+ if (strcmp (e->pw_name, "root"))
|
|
+ root_seen = true;
|
|
+ }
|
|
+
|
|
+ TEST_COMPARE (errno, 0);
|
|
+ TEST_VERIFY (root_seen);
|
|
+
|
|
+ errno = 0;
|
|
+ endpwent ();
|
|
+ TEST_COMPARE (errno, 0);
|
|
+
|
|
+ TEST_COMPARE_STRING (getenv ("_nss_test_errno_setpwent"), "yes");
|
|
+ TEST_COMPARE_STRING (getenv ("_nss_test_errno_getpwent_r"), "yes");
|
|
+ TEST_COMPARE_STRING (getenv ("_nss_test_errno_endpwent"), "yes");
|
|
+
|
|
+ return 0;
|
|
+}
|
|
+
|
|
+#include <support/test-driver.c>
|