From: Florian Weimer <fweimer@redhat.com>
To: libc-alpha@sourceware.org
Subject: [PATCH] elf: Initialize libc_map to NULL on namespace creation
Date: Wed, 24 Aug 2022 21:43:05 +0200 [thread overview]
Message-ID: <87mtbt5sxi.fsf@oldenburg.str.redhat.com> (raw)
It seems that a stale libc_map value will be used (and not
overwritten) by a dlmopen after a dlclose that has deallocated
the namespace. This may not be visible easily because the libc
link map can be allocated at the same address.
Fixes commit ec935dea6332cb22f9881cd1162bad156173f4b0 ("elf:
Implement __libc_early_init").
---
elf/dl-open.c | 4 ++++
1 file changed, 4 insertions(+)
diff --git a/elf/dl-open.c b/elf/dl-open.c
index dcc24130fe..582095a7fa 100644
--- a/elf/dl-open.c
+++ b/elf/dl-open.c
@@ -850,6 +850,10 @@ no more namespaces available for dlmopen()"));
++GL(dl_nns);
}
+ /* Clear any potential dangling libc link map references. */
+ GL(dl_ns)[nsid].libc_map = NULL;
+ GL(dl_ns)[nsid].libc_map_early_init = NULL;
+
_dl_debug_update (nsid)->r_state = RT_CONSISTENT;
}
/* Never allow loading a DSO in a namespace which is empty. Such
base-commit: 6f85dbf102ad7982409ba0fe96886caeb6389fef
next reply other threads:[~2022-08-24 19:43 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-08-24 19:43 Florian Weimer [this message]
2022-08-26 12:49 ` Florian Weimer
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