Re: [rfa/gdbserver] Fix crash in thread_db_get_tls_address

Ulrich Weigand
2009-01-22T15:06:33Z

Doug Evans wrote:

> Hi. I've run into similar situations with the thread layer not yet
> initialized. One aspect of this patch is a bit confusing. Maybe a
> comment is warranted.
>
> Returning -1 will cause server.c:handle_query to mark the packet as
> unknown which will in turn cause remote.c:packet_ok to mark the packet
> as disabled (on the gdb side). How does the packet get re-enabled if
> the thread layer is later initialized?

You're right -- I missed that. I guess we need to report an error
instead of marking the packet as unknown.

The following patch is changed to use TD_ERR ("generic error" seems to
be the best response -- I don't see a more specific code that would be
appropriate here).

Retested on powerpc64-linux (64-bit / 32-bit) with local gdbserver.

Bye,
Ulrich

ChangeLog:

* thread-db.c (thread_db_get_tls_address): Do not crash if
called when thread layer is not yet initialized.

Index: src/gdb/gdbserver/thread-db.c
===================================================================
--- src.orig/gdb/gdbserver/thread-db.c
+++ src/gdb/gdbserver/thread-db.c
@@ -388,6 +388,10 @@ thread_db_get_tls_address (struct thread
td_err_e err;
struct process_info *process;

+ /* If the thread layer is not (yet) initialized, fail. */
+ if (!all_symbols_looked_up)
+ return TD_ERR;
+
process = get_thread_process (thread);
if (!process->thread_known)
find_one_thread (process->lwpid);