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-rw-r--r--elf/Makefile5
-rw-r--r--elf/dl-object.c17
-rw-r--r--elf/rtld.c6
-rw-r--r--elf/setup-vdso.h2
-rw-r--r--elf/tst-audit22.c124
-rw-r--r--elf/tst-auditmod22.c51
-rw-r--r--include/dlfcn.h2
7 files changed, 199 insertions, 8 deletions
diff --git a/elf/Makefile b/elf/Makefile
index 7fcb9c9b2c..f427e2d6a3 100644
--- a/elf/Makefile
+++ b/elf/Makefile
@@ -232,6 +232,7 @@ tests += restest1 preloadtest loadfail multiload origtest resolvfail \
tst-dl-is_dso tst-ro-dynamic \
tst-audit18 \
tst-audit19b \
+ tst-audit22 \
tst-rtld-run-static \
# reldep9
tests-internal += loadtest unload unload2 circleload1 \
@@ -382,6 +383,7 @@ modules-names = testobj1 testobj2 testobj3 testobj4 testobj5 testobj6 \
tst-auditmod19a \
tst-auditmod19b \
tst-audit19bmod \
+ tst-auditmod22 \
# Most modules build with _ISOMAC defined, but those filtered out
# depend on internal headers.
@@ -1594,6 +1596,9 @@ $(objpfx)tst-audit19b.out: $(objpfx)tst-auditmod19b.so
$(objpfx)tst-audit19b: $(objpfx)tst-audit19bmod.so
tst-audit19b-ARGS = -- $(host-test-program-cmd)
+$(objpfx)tst-audit22.out: $(objpfx)tst-auditmod22.so
+tst-audit22-ARGS = -- $(host-test-program-cmd)
+
# tst-sonamemove links against an older implementation of the library.
LDFLAGS-tst-sonamemove-linkmod1.so = \
-Wl,--version-script=tst-sonamemove-linkmod1.map \
diff --git a/elf/dl-object.c b/elf/dl-object.c
index 1875599eb2..dee49a32d4 100644
--- a/elf/dl-object.c
+++ b/elf/dl-object.c
@@ -59,16 +59,19 @@ _dl_new_object (char *realname, const char *libname, int type,
{
#ifdef SHARED
unsigned int naudit;
- if (__glibc_unlikely ((mode & __RTLD_OPENEXEC) != 0))
+ if (__glibc_unlikely ((mode & (__RTLD_OPENEXEC | __RTLD_VDSO)) != 0))
{
- assert (type == lt_executable);
- assert (nsid == LM_ID_BASE);
+ if (mode & __RTLD_OPENEXEC)
+ {
+ assert (type == lt_executable);
+ assert (nsid == LM_ID_BASE);
- /* Ignore the specified libname for the main executable. It is
- only known with an explicit loader invocation. */
- libname = "";
+ /* Ignore the specified libname for the main executable. It is
+ only known with an explicit loader invocation. */
+ libname = "";
+ }
- /* We create the map for the executable before we know whether
+ /* We create the map for the executable and vDSO before we know whether
we have auditing libraries and if yes, how many. Assume the
worst. */
naudit = DL_NNS;
diff --git a/elf/rtld.c b/elf/rtld.c
index b215ce6909..e78001c2a4 100644
--- a/elf/rtld.c
+++ b/elf/rtld.c
@@ -1912,6 +1912,12 @@ dl_main (const ElfW(Phdr) *phdr,
assert (i == npreloads);
}
+#ifdef NEED_DL_SYSINFO_DSO
+ /* Now that the audit modules are opened, call la_objopen for the vDSO. */
+ if (GLRO(dl_sysinfo_map) != NULL)
+ _dl_audit_objopen (GLRO(dl_sysinfo_map), LM_ID_BASE);
+#endif
+
/* Load all the libraries specified by DT_NEEDED entries. If LD_PRELOAD
specified some libraries to load, these are inserted before the actual
dependencies in the executable's searchlist for symbol resolution. */
diff --git a/elf/setup-vdso.h b/elf/setup-vdso.h
index 3f20578046..2b013d974a 100644
--- a/elf/setup-vdso.h
+++ b/elf/setup-vdso.h
@@ -30,7 +30,7 @@ setup_vdso (struct link_map *main_map __attribute__ ((unused)),
We just want our data structures to describe it as if we had just
mapped and relocated it normally. */
struct link_map *l = _dl_new_object ((char *) "", "", lt_library, NULL,
- 0, LM_ID_BASE);
+ __RTLD_VDSO, LM_ID_BASE);
if (__glibc_likely (l != NULL))
{
l->l_phdr = ((const void *) GLRO(dl_sysinfo_dso)
diff --git a/elf/tst-audit22.c b/elf/tst-audit22.c
new file mode 100644
index 0000000000..18fd22a760
--- /dev/null
+++ b/elf/tst-audit22.c
@@ -0,0 +1,124 @@
+/* Check DTAUDIT and vDSO interaction.
+ Copyright (C) 2021 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 <getopt.h>
+#include <limits.h>
+#include <inttypes.h>
+#include <string.h>
+#include <stdlib.h>
+#include <support/capture_subprocess.h>
+#include <support/check.h>
+#include <support/xstdio.h>
+#include <support/support.h>
+#include <sys/auxv.h>
+
+static int restart;
+#define CMDLINE_OPTIONS \
+ { "restart", no_argument, &restart, 1 },
+
+static uintptr_t vdso_addr;
+
+static int
+handle_restart (void)
+{
+ fprintf (stderr, "vdso: %p\n", (void*) vdso_addr);
+ return 0;
+}
+
+static uintptr_t
+parse_address (const char *str)
+{
+ void *r;
+ TEST_COMPARE (sscanf (str, "%p\n", &r), 1);
+ return (uintptr_t) r;
+}
+
+static inline bool
+startswith (const char *str, const char *pre)
+{
+ size_t lenpre = strlen (pre);
+ size_t lenstr = strlen (str);
+ return lenstr >= lenpre && memcmp (pre, str, lenpre) == 0;
+}
+
+static int
+do_test (int argc, char *argv[])
+{
+ vdso_addr = getauxval (AT_SYSINFO_EHDR);
+ if (vdso_addr == 0)
+ FAIL_UNSUPPORTED ("getauxval (AT_SYSINFO_EHDR) returned 0");
+
+ /* We must have either:
+ - One our fource parameters left if called initially:
+ + path to ld.so optional
+ + "--library-path" optional
+ + the library path optional
+ + the application name */
+ if (restart)
+ return handle_restart ();
+
+ char *spargv[9];
+ int i = 0;
+ for (; i < argc - 1; i++)
+ spargv[i] = argv[i + 1];
+ spargv[i++] = (char *) "--direct";
+ spargv[i++] = (char *) "--restart";
+ spargv[i] = NULL;
+
+ setenv ("LD_AUDIT", "tst-auditmod22.so", 0);
+ struct support_capture_subprocess result
+ = support_capture_subprogram (spargv[0], spargv);
+ support_capture_subprocess_check (&result, "tst-audit22", 0, sc_allow_stderr);
+
+ /* The respawned process should always print the vDSO address (otherwise it
+ will fails as unsupported). However, on some architectures the audit
+ module might see the vDSO with l_addr being 0, meaning a fixed mapping
+ (linux-gate.so). In this case we don't check its value against
+ AT_SYSINFO_EHDR one. */
+ uintptr_t vdso_process = 0;
+ bool vdso_audit_found = false;
+ uintptr_t vdso_audit = 0;
+
+ FILE *out = fmemopen (result.err.buffer, result.err.length, "r");
+ TEST_VERIFY (out != NULL);
+ char *buffer = NULL;
+ size_t buffer_length = 0;
+ while (xgetline (&buffer, &buffer_length, out))
+ {
+ if (startswith (buffer, "vdso: "))
+ vdso_process = parse_address (buffer + strlen ("vdso: "));
+ else if (startswith (buffer, "vdso found: "))
+ {
+ vdso_audit = parse_address (buffer + strlen ("vdso found: "));
+ vdso_audit_found = true;
+ }
+ }
+
+ TEST_COMPARE (vdso_audit_found, true);
+ if (vdso_audit != 0)
+ TEST_COMPARE (vdso_process, vdso_audit);
+
+ free (buffer);
+ xfclose (out);
+
+ return 0;
+}
+
+#define TEST_FUNCTION_ARGV do_test
+#include <support/test-driver.c>
diff --git a/elf/tst-auditmod22.c b/elf/tst-auditmod22.c
new file mode 100644
index 0000000000..8e05ce8cbb
--- /dev/null
+++ b/elf/tst-auditmod22.c
@@ -0,0 +1,51 @@
+/* Check DTAUDIT and vDSO interaction.
+ Copyright (C) 2021 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 <link.h>
+#include <inttypes.h>
+#include <stdbool.h>
+#include <string.h>
+#include <stdio.h>
+#include <sys/auxv.h>
+
+static inline bool
+startswith (const char *str, const char *pre)
+{
+ size_t lenpre = strlen (pre);
+ size_t lenstr = strlen (str);
+ return lenstr < lenpre ? false : memcmp (pre, str, lenpre) == 0;
+}
+
+unsigned int
+la_version (unsigned int version)
+{
+ return LAV_CURRENT;
+}
+
+unsigned int
+la_objopen (struct link_map *map, Lmid_t lmid, uintptr_t *cookie)
+{
+ /* The linux-gate.so is placed at a fixed address, thus l_addr being 0,
+ and it might be the value reported as the AT_SYSINFO_EHDR. */
+ if (map->l_addr == 0 && startswith (map->l_name, "linux-gate.so"))
+ fprintf (stderr, "vdso found: %p\n", NULL);
+ else if (map->l_addr == getauxval (AT_SYSINFO_EHDR))
+ fprintf (stderr, "vdso found: %p\n", (void*) map->l_addr);
+
+ return 0;
+}
diff --git a/include/dlfcn.h b/include/dlfcn.h
index a4c283728f..e73294b0af 100644
--- a/include/dlfcn.h
+++ b/include/dlfcn.h
@@ -12,6 +12,8 @@
#define __RTLD_AUDIT 0x08000000
#define __RTLD_SECURE 0x04000000 /* Apply additional security checks. */
#define __RTLD_NOIFUNC 0x02000000 /* Suppress calling ifunc functions. */
+#define __RTLD_VDSO 0x01000000 /* Tell _dl_new_object the object is
+ system-loaded. */
#define __LM_ID_CALLER -2