diff options
| author | Saravana Kannan <saravanak@google.com> | 2021-04-01 21:03:40 -0700 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2021-04-05 09:14:18 +0200 |
| commit | eed6e41813deb9ee622cd9242341f21430d7789f (patch) | |
| tree | 91b999f50ba45512e35dbda8906988f2f87c5dd3 /drivers/base | |
| parent | e49d033bddf5b565044e2abe4241353959bc9120 (diff) | |
| download | lwn-eed6e41813deb9ee622cd9242341f21430d7789f.tar.gz lwn-eed6e41813deb9ee622cd9242341f21430d7789f.zip | |
driver core: Fix locking bug in deferred_probe_timeout_work_func()
list_for_each_entry_safe() is only useful if we are deleting nodes in a
linked list within the loop. It doesn't protect against other threads
adding/deleting nodes to the list in parallel. We need to grab
deferred_probe_mutex when traversing the deferred_probe_pending_list.
Cc: stable@vger.kernel.org
Fixes: 25b4e70dcce9 ("driver core: allow stopping deferred probe after init")
Signed-off-by: Saravana Kannan <saravanak@google.com>
Link: https://lore.kernel.org/r/20210402040342.2944858-2-saravanak@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/base')
| -rw-r--r-- | drivers/base/dd.c | 8 |
1 files changed, 5 insertions, 3 deletions
diff --git a/drivers/base/dd.c b/drivers/base/dd.c index e2cf3b29123e..37a5e5f8b221 100644 --- a/drivers/base/dd.c +++ b/drivers/base/dd.c @@ -292,14 +292,16 @@ int driver_deferred_probe_check_state(struct device *dev) static void deferred_probe_timeout_work_func(struct work_struct *work) { - struct device_private *private, *p; + struct device_private *p; driver_deferred_probe_timeout = 0; driver_deferred_probe_trigger(); flush_work(&deferred_probe_work); - list_for_each_entry_safe(private, p, &deferred_probe_pending_list, deferred_probe) - dev_info(private->device, "deferred probe pending\n"); + mutex_lock(&deferred_probe_mutex); + list_for_each_entry(p, &deferred_probe_pending_list, deferred_probe) + dev_info(p->device, "deferred probe pending\n"); + mutex_unlock(&deferred_probe_mutex); wake_up_all(&probe_timeout_waitqueue); } static DECLARE_DELAYED_WORK(deferred_probe_timeout_work, deferred_probe_timeout_work_func); |