dlfcn: Failures after dlmopen should not terminate process [BZ #24772]

Commit 9e78f6f6e7134a5f299cc8de77370218f8019237 ("Implement
_dl_catch_error, _dl_signal_error in libc.so [BZ #16628]") has the
side effect that distinct namespaces, as created by dlmopen, now have
separate implementations of the rtld exception mechanism.  This means
that the call to _dl_catch_error from libdl in a secondary namespace
does not actually install an exception handler because the
thread-local variable catch_hook in the libc.so copy in the secondary
namespace is distinct from that of the base namepace.  As a result, a
dlsym/dlopen/... failure in a secondary namespace terminates the process
with a dynamic linker error because it looks to the exception handler
mechanism as if no handler has been installed.

This commit restores GLRO (dl_catch_error) and uses it to set the
handler in the base namespace.

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>

1 files changed, 4 insertions, 2 deletions

diff --git a/dlfcn/dlerror.c b/dlfcn/dlerror.c
index 48b4c25bea..947b7c10c6 100644
--- a/dlfcn/dlerror.c
+++ b/dlfcn/dlerror.c
@@ -167,8 +167,10 @@ _dlerror_run (void (*operate) (void *), void *args)
       result->errstring = NULL;
     }
 
-  result->errcode = _dl_catch_error (&result->objname, &result->errstring,
-				     &result->malloced, operate, args);
+  result->errcode = GLRO (dl_catch_error) (&result->objname,
+					   &result->errstring,
+					   &result->malloced,
+					   operate, args);
 
   /* If no error we mark that no error string is available.  */
   result->returned = result->errstring == NULL;