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* [glibc/azanella/mseal] elf: Enable RTLD_NODELETE on __libc_unwind_link_get
@ 2024-06-04 13:22 Adhemerval Zanella
0 siblings, 0 replies; 5+ messages in thread
From: Adhemerval Zanella @ 2024-06-04 13:22 UTC (permalink / raw)
To: glibc-cvs
https://sourceware.org/git/gitweb.cgi?p=glibc.git;h=9603fb34c90aef118bd51d96977cdc15643bf908
commit 9603fb34c90aef118bd51d96977cdc15643bf908
Author: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Date: Tue Jun 4 10:07:41 2024 -0300
elf: Enable RTLD_NODELETE on __libc_unwind_link_get
So the libgcc_s.so can also be sealed. The library is loaded once
and not unloaded during process execution (only for memory debug
with __libc_unwind_link_freeres).
Diff:
---
include/dlfcn.h | 2 ++
misc/unwind-link.c | 5 +++--
2 files changed, 5 insertions(+), 2 deletions(-)
diff --git a/include/dlfcn.h b/include/dlfcn.h
index f49ee1b0c9..06e2ecbdd2 100644
--- a/include/dlfcn.h
+++ b/include/dlfcn.h
@@ -50,6 +50,8 @@ extern char **__libc_argv attribute_hidden;
better error handling semantics for the library. */
#define __libc_dlopen(name) \
__libc_dlopen_mode (name, RTLD_NOW | __RTLD_DLOPEN)
+#define __libc_dlopen_nodelete(name) \
+ __libc_dlopen_mode (name, RTLD_NODELETE | RTLD_NOW | __RTLD_DLOPEN)
extern void *__libc_dlopen_mode (const char *__name, int __mode)
attribute_hidden;
extern void *__libc_dlsym (void *__map, const char *__name)
diff --git a/misc/unwind-link.c b/misc/unwind-link.c
index 213a0162a4..7267ecbec3 100644
--- a/misc/unwind-link.c
+++ b/misc/unwind-link.c
@@ -48,7 +48,7 @@ __libc_unwind_link_get (void)
/* Initialize a copy of the data, so that we do not need about
unlocking in case the dynamic loader somehow triggers
unwinding. */
- void *local_libgcc_handle = __libc_dlopen (LIBGCC_S_SO);
+ void *local_libgcc_handle = __libc_dlopen_nodelete (LIBGCC_S_SO);
if (local_libgcc_handle == NULL)
{
__libc_lock_unlock (lock);
@@ -100,7 +100,8 @@ __libc_unwind_link_get (void)
__libc_lock_lock (lock);
if (atomic_load_relaxed (&global_libgcc_handle) != NULL)
- /* This thread lost the race. Clean up. */
+ /* This thread lost the race. Drop the l_direct_opencount and issue
+ the debug log. */
__libc_dlclose (local_libgcc_handle);
else
{
^ permalink raw reply [flat|nested] 5+ messages in thread
* [glibc/azanella/mseal] elf: Enable RTLD_NODELETE on __libc_unwind_link_get
@ 2024-06-21 14:30 Adhemerval Zanella
0 siblings, 0 replies; 5+ messages in thread
From: Adhemerval Zanella @ 2024-06-21 14:30 UTC (permalink / raw)
To: glibc-cvs
https://sourceware.org/git/gitweb.cgi?p=glibc.git;h=fa6cd21f529d4baf555d89a8fb7acabd89e79b0f
commit fa6cd21f529d4baf555d89a8fb7acabd89e79b0f
Author: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Date: Fri Jun 7 21:12:18 2024 +0000
elf: Enable RTLD_NODELETE on __libc_unwind_link_get
The libgcc_s.so can also be sealed. The library is loaded once
and not unloaded during process execution (only for memory debug
with __libc_unwind_link_freeres).
Checked on x86_64-linux-gnu and aarch64-linux-gnu.
Diff:
---
include/dlfcn.h | 2 ++
manual/tunables.texi | 4 ++++
misc/unwind-link.c | 5 +++--
sysdeps/unix/sysv/linux/tst-dl_mseal.c | 13 +++++++++++++
4 files changed, 22 insertions(+), 2 deletions(-)
diff --git a/include/dlfcn.h b/include/dlfcn.h
index f49ee1b0c9..06e2ecbdd2 100644
--- a/include/dlfcn.h
+++ b/include/dlfcn.h
@@ -50,6 +50,8 @@ extern char **__libc_argv attribute_hidden;
better error handling semantics for the library. */
#define __libc_dlopen(name) \
__libc_dlopen_mode (name, RTLD_NOW | __RTLD_DLOPEN)
+#define __libc_dlopen_nodelete(name) \
+ __libc_dlopen_mode (name, RTLD_NODELETE | RTLD_NOW | __RTLD_DLOPEN)
extern void *__libc_dlopen_mode (const char *__name, int __mode)
attribute_hidden;
extern void *__libc_dlsym (void *__map, const char *__name)
diff --git a/manual/tunables.texi b/manual/tunables.texi
index 65ec47c3d2..a5cc08ddf2 100644
--- a/manual/tunables.texi
+++ b/manual/tunables.texi
@@ -380,6 +380,10 @@ Any preload libraries.
@item
Any library loaded with @code{dlopen} with @code{RTLD_NODELETE} flag.
+
+@item
+Any runtime library used for process unwind (such as required by @code{backtrace}
+or @code{pthread_exit}).
@end itemize
The tunable accepts three diferent values: @samp{0} where sealing is disabled,
diff --git a/misc/unwind-link.c b/misc/unwind-link.c
index 213a0162a4..7267ecbec3 100644
--- a/misc/unwind-link.c
+++ b/misc/unwind-link.c
@@ -48,7 +48,7 @@ __libc_unwind_link_get (void)
/* Initialize a copy of the data, so that we do not need about
unlocking in case the dynamic loader somehow triggers
unwinding. */
- void *local_libgcc_handle = __libc_dlopen (LIBGCC_S_SO);
+ void *local_libgcc_handle = __libc_dlopen_nodelete (LIBGCC_S_SO);
if (local_libgcc_handle == NULL)
{
__libc_lock_unlock (lock);
@@ -100,7 +100,8 @@ __libc_unwind_link_get (void)
__libc_lock_lock (lock);
if (atomic_load_relaxed (&global_libgcc_handle) != NULL)
- /* This thread lost the race. Clean up. */
+ /* This thread lost the race. Drop the l_direct_opencount and issue
+ the debug log. */
__libc_dlclose (local_libgcc_handle);
else
{
diff --git a/sysdeps/unix/sysv/linux/tst-dl_mseal.c b/sysdeps/unix/sysv/linux/tst-dl_mseal.c
index 72a33d04c7..da1a3ebe5a 100644
--- a/sysdeps/unix/sysv/linux/tst-dl_mseal.c
+++ b/sysdeps/unix/sysv/linux/tst-dl_mseal.c
@@ -19,6 +19,7 @@
#include <array_length.h>
#include <errno.h>
#include <getopt.h>
+#include <gnu/lib-names.h>
#include <inttypes.h>
#include <libgen.h>
#include <stdio.h>
@@ -31,6 +32,7 @@
#include <support/support.h>
#include <support/xdlfcn.h>
#include <support/xstdio.h>
+#include <support/xthread.h>
#define LIB_PRELOAD "lib-tst-dl_mseal-preload.so"
@@ -70,6 +72,7 @@ static const char *expected_sealed_libs[] =
LIB_NEEDED_2,
LIB_DLOPEN_NODELETE,
LIB_DLOPEN_NODELETE_DEP,
+ LIBGCC_S_SO,
#endif
"[vdso]",
};
@@ -100,6 +103,13 @@ is_in_string_list (const char *s, const char *const list[], size_t len)
return -1;
}
+static void *
+tf (void *closure)
+{
+ pthread_exit (NULL);
+ return NULL;
+}
+
static int
handle_restart (void)
{
@@ -108,6 +118,9 @@ handle_restart (void)
xdlopen (LIB_DLOPEN_DEFAULT, RTLD_NOW);
#endif
+ /* pthread_exit will load LIBGCC_S_SO. */
+ xpthread_join (xpthread_create (NULL, tf, NULL));
+
FILE *fp = xfopen ("/proc/self/maps", "r");
char *line = NULL;
size_t linesiz = 0;
^ permalink raw reply [flat|nested] 5+ messages in thread
* [glibc/azanella/mseal] elf: Enable RTLD_NODELETE on __libc_unwind_link_get
@ 2024-06-19 13:04 Adhemerval Zanella
0 siblings, 0 replies; 5+ messages in thread
From: Adhemerval Zanella @ 2024-06-19 13:04 UTC (permalink / raw)
To: glibc-cvs
https://sourceware.org/git/gitweb.cgi?p=glibc.git;h=00c5ee1da3973e352f9adab4c4e7dd378b6593ef
commit 00c5ee1da3973e352f9adab4c4e7dd378b6593ef
Author: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Date: Fri Jun 7 21:12:18 2024 +0000
elf: Enable RTLD_NODELETE on __libc_unwind_link_get
The libgcc_s.so can also be sealed. The library is loaded once
and not unloaded during process execution (only for memory debug
with __libc_unwind_link_freeres).
Checked on x86_64-linux-gnu and aarch64-linux-gnu.
Diff:
---
include/dlfcn.h | 2 ++
manual/tunables.texi | 4 ++++
misc/unwind-link.c | 5 +++--
sysdeps/unix/sysv/linux/tst-dl_mseal.c | 13 +++++++++++++
4 files changed, 22 insertions(+), 2 deletions(-)
diff --git a/include/dlfcn.h b/include/dlfcn.h
index f49ee1b0c9..06e2ecbdd2 100644
--- a/include/dlfcn.h
+++ b/include/dlfcn.h
@@ -50,6 +50,8 @@ extern char **__libc_argv attribute_hidden;
better error handling semantics for the library. */
#define __libc_dlopen(name) \
__libc_dlopen_mode (name, RTLD_NOW | __RTLD_DLOPEN)
+#define __libc_dlopen_nodelete(name) \
+ __libc_dlopen_mode (name, RTLD_NODELETE | RTLD_NOW | __RTLD_DLOPEN)
extern void *__libc_dlopen_mode (const char *__name, int __mode)
attribute_hidden;
extern void *__libc_dlsym (void *__map, const char *__name)
diff --git a/manual/tunables.texi b/manual/tunables.texi
index 65ec47c3d2..a5cc08ddf2 100644
--- a/manual/tunables.texi
+++ b/manual/tunables.texi
@@ -380,6 +380,10 @@ Any preload libraries.
@item
Any library loaded with @code{dlopen} with @code{RTLD_NODELETE} flag.
+
+@item
+Any runtime library used for process unwind (such as required by @code{backtrace}
+or @code{pthread_exit}).
@end itemize
The tunable accepts three diferent values: @samp{0} where sealing is disabled,
diff --git a/misc/unwind-link.c b/misc/unwind-link.c
index 213a0162a4..7267ecbec3 100644
--- a/misc/unwind-link.c
+++ b/misc/unwind-link.c
@@ -48,7 +48,7 @@ __libc_unwind_link_get (void)
/* Initialize a copy of the data, so that we do not need about
unlocking in case the dynamic loader somehow triggers
unwinding. */
- void *local_libgcc_handle = __libc_dlopen (LIBGCC_S_SO);
+ void *local_libgcc_handle = __libc_dlopen_nodelete (LIBGCC_S_SO);
if (local_libgcc_handle == NULL)
{
__libc_lock_unlock (lock);
@@ -100,7 +100,8 @@ __libc_unwind_link_get (void)
__libc_lock_lock (lock);
if (atomic_load_relaxed (&global_libgcc_handle) != NULL)
- /* This thread lost the race. Clean up. */
+ /* This thread lost the race. Drop the l_direct_opencount and issue
+ the debug log. */
__libc_dlclose (local_libgcc_handle);
else
{
diff --git a/sysdeps/unix/sysv/linux/tst-dl_mseal.c b/sysdeps/unix/sysv/linux/tst-dl_mseal.c
index 72a33d04c7..da1a3ebe5a 100644
--- a/sysdeps/unix/sysv/linux/tst-dl_mseal.c
+++ b/sysdeps/unix/sysv/linux/tst-dl_mseal.c
@@ -19,6 +19,7 @@
#include <array_length.h>
#include <errno.h>
#include <getopt.h>
+#include <gnu/lib-names.h>
#include <inttypes.h>
#include <libgen.h>
#include <stdio.h>
@@ -31,6 +32,7 @@
#include <support/support.h>
#include <support/xdlfcn.h>
#include <support/xstdio.h>
+#include <support/xthread.h>
#define LIB_PRELOAD "lib-tst-dl_mseal-preload.so"
@@ -70,6 +72,7 @@ static const char *expected_sealed_libs[] =
LIB_NEEDED_2,
LIB_DLOPEN_NODELETE,
LIB_DLOPEN_NODELETE_DEP,
+ LIBGCC_S_SO,
#endif
"[vdso]",
};
@@ -100,6 +103,13 @@ is_in_string_list (const char *s, const char *const list[], size_t len)
return -1;
}
+static void *
+tf (void *closure)
+{
+ pthread_exit (NULL);
+ return NULL;
+}
+
static int
handle_restart (void)
{
@@ -108,6 +118,9 @@ handle_restart (void)
xdlopen (LIB_DLOPEN_DEFAULT, RTLD_NOW);
#endif
+ /* pthread_exit will load LIBGCC_S_SO. */
+ xpthread_join (xpthread_create (NULL, tf, NULL));
+
FILE *fp = xfopen ("/proc/self/maps", "r");
char *line = NULL;
size_t linesiz = 0;
^ permalink raw reply [flat|nested] 5+ messages in thread
* [glibc/azanella/mseal] elf: Enable RTLD_NODELETE on __libc_unwind_link_get
@ 2024-06-04 22:57 Adhemerval Zanella
0 siblings, 0 replies; 5+ messages in thread
From: Adhemerval Zanella @ 2024-06-04 22:57 UTC (permalink / raw)
To: glibc-cvs
https://sourceware.org/git/gitweb.cgi?p=glibc.git;h=1dfe4b60eefbf3d72b1d3951be422d4345b293ab
commit 1dfe4b60eefbf3d72b1d3951be422d4345b293ab
Author: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Date: Tue Jun 4 10:07:41 2024 -0300
elf: Enable RTLD_NODELETE on __libc_unwind_link_get
So the libgcc_s.so can also be sealed. The library is loaded once
and not unloaded during process execution (only for memory debug
with __libc_unwind_link_freeres).
Diff:
---
include/dlfcn.h | 2 ++
misc/unwind-link.c | 5 +++--
2 files changed, 5 insertions(+), 2 deletions(-)
diff --git a/include/dlfcn.h b/include/dlfcn.h
index f49ee1b0c9..06e2ecbdd2 100644
--- a/include/dlfcn.h
+++ b/include/dlfcn.h
@@ -50,6 +50,8 @@ extern char **__libc_argv attribute_hidden;
better error handling semantics for the library. */
#define __libc_dlopen(name) \
__libc_dlopen_mode (name, RTLD_NOW | __RTLD_DLOPEN)
+#define __libc_dlopen_nodelete(name) \
+ __libc_dlopen_mode (name, RTLD_NODELETE | RTLD_NOW | __RTLD_DLOPEN)
extern void *__libc_dlopen_mode (const char *__name, int __mode)
attribute_hidden;
extern void *__libc_dlsym (void *__map, const char *__name)
diff --git a/misc/unwind-link.c b/misc/unwind-link.c
index 213a0162a4..7267ecbec3 100644
--- a/misc/unwind-link.c
+++ b/misc/unwind-link.c
@@ -48,7 +48,7 @@ __libc_unwind_link_get (void)
/* Initialize a copy of the data, so that we do not need about
unlocking in case the dynamic loader somehow triggers
unwinding. */
- void *local_libgcc_handle = __libc_dlopen (LIBGCC_S_SO);
+ void *local_libgcc_handle = __libc_dlopen_nodelete (LIBGCC_S_SO);
if (local_libgcc_handle == NULL)
{
__libc_lock_unlock (lock);
@@ -100,7 +100,8 @@ __libc_unwind_link_get (void)
__libc_lock_lock (lock);
if (atomic_load_relaxed (&global_libgcc_handle) != NULL)
- /* This thread lost the race. Clean up. */
+ /* This thread lost the race. Drop the l_direct_opencount and issue
+ the debug log. */
__libc_dlclose (local_libgcc_handle);
else
{
^ permalink raw reply [flat|nested] 5+ messages in thread
* [glibc/azanella/mseal] elf: Enable RTLD_NODELETE on __libc_unwind_link_get
@ 2024-06-04 14:08 Adhemerval Zanella
0 siblings, 0 replies; 5+ messages in thread
From: Adhemerval Zanella @ 2024-06-04 14:08 UTC (permalink / raw)
To: glibc-cvs
https://sourceware.org/git/gitweb.cgi?p=glibc.git;h=3b8c02ca8b20b9ae1c0872426131402dc2b50695
commit 3b8c02ca8b20b9ae1c0872426131402dc2b50695
Author: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Date: Tue Jun 4 10:07:41 2024 -0300
elf: Enable RTLD_NODELETE on __libc_unwind_link_get
So the libgcc_s.so can also be sealed. The library is loaded once
and not unloaded during process execution (only for memory debug
with __libc_unwind_link_freeres).
Diff:
---
include/dlfcn.h | 2 ++
misc/unwind-link.c | 5 +++--
2 files changed, 5 insertions(+), 2 deletions(-)
diff --git a/include/dlfcn.h b/include/dlfcn.h
index f49ee1b0c9..06e2ecbdd2 100644
--- a/include/dlfcn.h
+++ b/include/dlfcn.h
@@ -50,6 +50,8 @@ extern char **__libc_argv attribute_hidden;
better error handling semantics for the library. */
#define __libc_dlopen(name) \
__libc_dlopen_mode (name, RTLD_NOW | __RTLD_DLOPEN)
+#define __libc_dlopen_nodelete(name) \
+ __libc_dlopen_mode (name, RTLD_NODELETE | RTLD_NOW | __RTLD_DLOPEN)
extern void *__libc_dlopen_mode (const char *__name, int __mode)
attribute_hidden;
extern void *__libc_dlsym (void *__map, const char *__name)
diff --git a/misc/unwind-link.c b/misc/unwind-link.c
index 213a0162a4..7267ecbec3 100644
--- a/misc/unwind-link.c
+++ b/misc/unwind-link.c
@@ -48,7 +48,7 @@ __libc_unwind_link_get (void)
/* Initialize a copy of the data, so that we do not need about
unlocking in case the dynamic loader somehow triggers
unwinding. */
- void *local_libgcc_handle = __libc_dlopen (LIBGCC_S_SO);
+ void *local_libgcc_handle = __libc_dlopen_nodelete (LIBGCC_S_SO);
if (local_libgcc_handle == NULL)
{
__libc_lock_unlock (lock);
@@ -100,7 +100,8 @@ __libc_unwind_link_get (void)
__libc_lock_lock (lock);
if (atomic_load_relaxed (&global_libgcc_handle) != NULL)
- /* This thread lost the race. Clean up. */
+ /* This thread lost the race. Drop the l_direct_opencount and issue
+ the debug log. */
__libc_dlclose (local_libgcc_handle);
else
{
^ permalink raw reply [flat|nested] 5+ messages in thread
end of thread, other threads:[~2024-06-21 14:30 UTC | newest]
Thread overview: 5+ messages (download: mbox.gz / follow: Atom feed)
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2024-06-04 13:22 [glibc/azanella/mseal] elf: Enable RTLD_NODELETE on __libc_unwind_link_get Adhemerval Zanella
2024-06-04 14:08 Adhemerval Zanella
2024-06-04 22:57 Adhemerval Zanella
2024-06-19 13:04 Adhemerval Zanella
2024-06-21 14:30 Adhemerval Zanella
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