glibc/SOURCES/glibc-rh2121746-2.patch
2023-05-17 01:33:08 +00:00

99 lines
3.1 KiB
Diff

From 2c42257314536b94cc8d52edede86e94e98c1436 Mon Sep 17 00:00:00 2001
From: Florian Weimer <fweimer@redhat.com>
Date: Fri, 14 Oct 2022 11:02:25 +0200
Subject: [PATCH] elf: Do not completely clear reused namespace in dlmopen (bug
29600)
Content-type: text/plain; charset=UTF-8
The data in the _ns_debug member must be preserved, otherwise
_dl_debug_initialize enters an infinite loop. To be conservative,
only clear the libc_map member for now, to fix bug 29528.
Fixes commit d0e357ff45a75553dee3b17ed7d303bfa544f6fe
("elf: Call __libc_early_init for reused namespaces (bug 29528)"),
by reverting most of it.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>
---
elf/dl-open.c | 14 ++++++--------
elf/tst-dlmopen-twice.c | 28 ++++++++++++++++++++++++----
2 files changed, 30 insertions(+), 12 deletions(-)
diff --git a/elf/dl-open.c b/elf/dl-open.c
index 46e8066fd8..e7db5e9642 100644
--- a/elf/dl-open.c
+++ b/elf/dl-open.c
@@ -836,15 +836,13 @@ _dl_open (const char *file, int mode, co
_dl_signal_error (EINVAL, file, NULL, N_("\
no more namespaces available for dlmopen()"));
}
+ else if (nsid == GL(dl_nns))
+ {
+ __rtld_lock_initialize (GL(dl_ns)[nsid]._ns_unique_sym_table.lock);
+ ++GL(dl_nns);
+ }
- if (nsid == GL(dl_nns))
- ++GL(dl_nns);
-
- /* Initialize the new namespace. Most members are
- zero-initialized, only the lock needs special treatment. */
- memset (&GL(dl_ns)[nsid], 0, sizeof (GL(dl_ns)[nsid]));
- __rtld_lock_initialize (GL(dl_ns)[nsid]._ns_unique_sym_table.lock);
-
+ GL(dl_ns)[nsid].libc_map = NULL;
_dl_debug_initialize (0, nsid)->r_state = RT_CONSISTENT;
}
/* Never allow loading a DSO in a namespace which is empty. Such
diff --git a/elf/tst-dlmopen-twice.c b/elf/tst-dlmopen-twice.c
index 449f3c8fa9..70c71fe19c 100644
--- a/elf/tst-dlmopen-twice.c
+++ b/elf/tst-dlmopen-twice.c
@@ -16,18 +16,38 @@
License along with the GNU C Library; if not, see
<https://www.gnu.org/licenses/>. */
-#include <support/xdlfcn.h>
+#include <stdio.h>
#include <support/check.h>
+#include <support/xdlfcn.h>
-static int
-do_test (void)
+/* Run the test multiple times, to check finding a new namespace while
+ another namespace is already in use. This used to trigger bug 29600. */
+static void
+recurse (int depth)
{
- void *handle = xdlmopen (LM_ID_NEWLM, "tst-dlmopen-twice-mod1.so", RTLD_NOW);
+ if (depth == 0)
+ return;
+
+ printf ("info: running at depth %d\n", depth);
+ void *handle = xdlmopen (LM_ID_NEWLM, "tst-dlmopen-twice-mod1.so",
+ RTLD_NOW);
xdlclose (handle);
handle = xdlmopen (LM_ID_NEWLM, "tst-dlmopen-twice-mod2.so", RTLD_NOW);
int (*run_check) (void) = xdlsym (handle, "run_check");
TEST_COMPARE (run_check (), 0);
+ recurse (depth - 1);
xdlclose (handle);
+}
+
+static int
+do_test (void)
+{
+ /* First run the test without nesting. */
+ recurse (1);
+
+ /* Then with nesting. The constant needs to be less than the
+ internal DL_NNS namespace constant. */
+ recurse (10);
return 0;
}
--
2.31.1