[glibc/release/2.34/master] elf: Replace nsid with args.nsid [BZ #27609]

[glibc/release/2.34/master] elf: Replace nsid with args.nsid [BZ #27609]

[H.J. Lu]

https://sourceware.org/git/gitweb.cgi?p=glibc.git;h=79528414dc1578800cbf1fba2fbdb6335f4f39bf

commit 79528414dc1578800cbf1fba2fbdb6335f4f39bf
Author: H.J. Lu <hjl.tools@gmail.com>
Date:   Thu Sep 30 10:29:17 2021 -0700

    elf: Replace nsid with args.nsid [BZ #27609]
    
    commit ec935dea6332cb22f9881cd1162bad156173f4b0
    Author: Florian Weimer <fweimer@redhat.com>
    Date:   Fri Apr 24 22:31:15 2020 +0200
    
        elf: Implement __libc_early_init
    
    has
    
    @@ -856,6 +876,11 @@ no more namespaces available for dlmopen()"));
       /* See if an error occurred during loading.  */
       if (__glibc_unlikely (exception.errstring != NULL))
         {
    +      /* Avoid keeping around a dangling reference to the libc.so link
    +   map in case it has been cached in libc_map.  */
    +      if (!args.libc_already_loaded)
    +  GL(dl_ns)[nsid].libc_map = NULL;
    +
    
    do_dlopen calls _dl_open with nsid == __LM_ID_CALLER (-2), which calls
    dl_open_worker with args.nsid = nsid.  dl_open_worker updates args.nsid
    if it is __LM_ID_CALLER.  After dl_open_worker returns, it is wrong to
    use nsid.
    
    Replace nsid with args.nsid after dl_open_worker returns.  This fixes
    BZ #27609.
    
    (cherry picked from commit 1e1ecea62e899acb58c3fdf3b320a0833ddd0dff)

Diff:
---
 elf/dl-open.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/elf/dl-open.c b/elf/dl-open.c
index ec386626f9..41c7250bf6 100644
--- a/elf/dl-open.c
+++ b/elf/dl-open.c
@@ -886,7 +886,7 @@ no more namespaces available for dlmopen()"));
       /* Avoid keeping around a dangling reference to the libc.so link
 	 map in case it has been cached in libc_map.  */
       if (!args.libc_already_loaded)
-	GL(dl_ns)[nsid].libc_map = NULL;
+	GL(dl_ns)[args.nsid].libc_map = NULL;
 
       /* Remove the object from memory.  It may be in an inconsistent
 	 state if relocation failed, for example.  */