sparc: Fix cleanup crash in bbc_envctrl_cleanup()
If kthread_run() fails or never gets to run we'll have NULL
or a pointer encoded error in kenvctrld_task, rather than
a legitimate task pointer.
So this makes bbc_envctrl_cleanup() crash as it passed this
bogus pointer into kthread_stop().
Reported-by: BERTRAND Joël <joel.bertrand@systella.fr>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/sbus/char/bbc_envctrl.c b/drivers/sbus/char/bbc_envctrl.c
index 15dab96..7c815d3 100644
--- a/drivers/sbus/char/bbc_envctrl.c
+++ b/drivers/sbus/char/bbc_envctrl.c
@@ -537,8 +537,12 @@
}
if (temp_index != 0 && fan_index != 0) {
kenvctrld_task = kthread_run(kenvctrld, NULL, "kenvctrld");
- if (IS_ERR(kenvctrld_task))
- return PTR_ERR(kenvctrld_task);
+ if (IS_ERR(kenvctrld_task)) {
+ int err = PTR_ERR(kenvctrld_task);
+
+ kenvctrld_task = NULL;
+ return err;
+ }
}
return 0;
@@ -561,7 +565,8 @@
struct bbc_cpu_temperature *tp, *tpos;
struct bbc_fan_control *fp, *fpos;
- kthread_stop(kenvctrld_task);
+ if (kenvctrld_task)
+ kthread_stop(kenvctrld_task);
list_for_each_entry_safe(tp, tpos, &bp->temps, bp_list) {
list_del(&tp->bp_list);