drbd_disconnect: grab meta.socket mutex as well
Fixes a race and potential kernel panic if e.g. the worker was just
about to send a few P_RS_IS_IN_SYNC via the meta socket for checksum
based resync, while the receiver destroys the sockets in
drbd_disconnect.
To make sure no-one is using the meta socket,
it is not enough to stop the asender...
Grab the meta socket mutex before destroying it.
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
diff --git a/drivers/block/drbd/drbd_main.c b/drivers/block/drbd/drbd_main.c
index b2d347d..67e0fc5 100644
--- a/drivers/block/drbd/drbd_main.c
+++ b/drivers/block/drbd/drbd_main.c
@@ -3173,14 +3173,18 @@
void drbd_free_sock(struct drbd_conf *mdev)
{
if (mdev->data.socket) {
+ mutex_lock(&mdev->data.mutex);
kernel_sock_shutdown(mdev->data.socket, SHUT_RDWR);
sock_release(mdev->data.socket);
mdev->data.socket = NULL;
+ mutex_unlock(&mdev->data.mutex);
}
if (mdev->meta.socket) {
+ mutex_lock(&mdev->meta.mutex);
kernel_sock_shutdown(mdev->meta.socket, SHUT_RDWR);
sock_release(mdev->meta.socket);
mdev->meta.socket = NULL;
+ mutex_unlock(&mdev->meta.mutex);
}
}