[PATCH 2/3] dl-audit: avoid closing fake ld.so [BZ #30127]

[Stas Sergeev <stsp2@yandex.ru>]

When new namespace is created, the fake ld.so object is created
that refers to main one via l_real pointer. Such object is not
passed to la_objopen() but is passed to la_objclose(), resulting
in an unrecognized cookie.
This patch avoids passing such objects to la_objclose().

The test-case for this is presented in a next patch.

Signed-off-by: Stas Sergeev <stsp2@yandex.ru>
---
 elf/dl-audit.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/elf/dl-audit.c b/elf/dl-audit.c
index 00e794aa26..ebfca887aa 100644
--- a/elf/dl-audit.c
+++ b/elf/dl-audit.c
@@ -96,7 +96,9 @@ void
 _dl_audit_objclose (struct link_map *l)
 {
   if (__glibc_likely (GLRO(dl_naudit) == 0)
-      || GL(dl_ns)[l->l_ns]._ns_loaded->l_auditing)
+      || GL(dl_ns)[l->l_ns]._ns_loaded->l_auditing
+      /* In non-base NS skip closing "fake" ld.so as it was not opened. */
+      || l->l_real != l)
     return;
 
   struct audit_ifaces *afct = GLRO(dl_audit);
-- 
2.37.2