Currently, if someone modprobes and rmmods rcuscale successfully, but
the next run errors out during the modprobe, non-NULL pointers to freed
memory will remain. If the run after that also errors out during the
modprobe, there will be double-free bugs.
This commit therefore NULLs out top-level pointers to memory that has
just been freed.
Signed-off-by: Paul E. McKenney <paulmck@xxxxxxxxxx>
---
kernel/rcu/rcuscale.c | 5 +++++
1 file changed, 5 insertions(+)
diff --git a/kernel/rcu/rcuscale.c b/kernel/rcu/rcuscale.c
index f945f8175e859..13d379c179248 100644
--- a/kernel/rcu/rcuscale.c
+++ b/kernel/rcu/rcuscale.c
@@ -819,6 +819,7 @@ kfree_scale_cleanup(void)
torture_stop_kthread(kfree_scale_thread,
kfree_reader_tasks[i]);
kfree(kfree_reader_tasks);
+ kfree_reader_tasks = NULL;
}
torture_cleanup_end();
@@ -987,6 +988,7 @@ rcu_scale_cleanup(void)
torture_stop_kthread(rcu_scale_reader,
reader_tasks[i]);
kfree(reader_tasks);
+ reader_tasks = NULL;
}
if (writer_tasks) {
@@ -1043,8 +1045,11 @@ rcu_scale_cleanup(void)
}
}
kfree(writer_tasks);
+ writer_tasks = NULL;
kfree(writer_durations);
+ writer_durations = NULL;
kfree(writer_n_durations);
+ writer_n_durations = NULL;
kfree(writer_freelists);
writer_freelists = NULL;
}
--
2.40.1
