dock: fix dereference after kfree()

dock_remove() calls kfree() on dock_station so we should use
list_for_each_entry_safe() to avoid dereferencing freed memory.

Found by smatch (http://repo.or.cz/w/smatch.git/).  Compile tested.

Signed-off-by: Dan Carpenter <error27@gmail.com>
Signed-off-by: Len Brown <len.brown@intel.com>

1 files changed, 2 insertions, 1 deletions

diff --git a/drivers/acpi/dock.c b/drivers/acpi/dock.c
index 35094f230b1e..8f62fa01a9c7 100644
--- a/drivers/acpi/dock.c
+++ b/drivers/acpi/dock.c
@@ -1146,9 +1146,10 @@ static int __init dock_init(void)
 static void __exit dock_exit(void)
 {
         struct dock_station *dock_station;
+        struct dock_station *tmp;
 
         unregister_acpi_bus_notifier(&dock_acpi_notifier);
-        list_for_each_entry(dock_station, &dock_stations, sibiling)
+        list_for_each_entry_safe(dock_station, tmp, &dock_stations, sibiling)
                 dock_remove(dock_station);
 }