[PATCH V3 1/3] tcm_vhost: Add missed lock in vhost_scsi_clear_endpoint()

Asias He
2013-03-15T01:14:05Z

tv_tpg->tv_tpg_vhost_count should be protected by tv_tpg->tv_tpg_mutex.

Signed-off-by: Asias He <asias at redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha at redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini at redhat.com>
---
 drivers/vhost/tcm_vhost.c | 12 ++++++++----
 1 file changed, 8 insertions(+), 4 deletions(-)

diff --git a/drivers/vhost/tcm_vhost.c b/drivers/vhost/tcm_vhost.c
index 9951297..79d3aea 100644
--- a/drivers/vhost/tcm_vhost.c
+++ b/drivers/vhost/tcm_vhost.c
@@ -850,7 +850,7 @@ static int vhost_scsi_clear_endpoint(
 	for (index = 0; index < vs->dev.nvqs; ++index) {
 		if (!vhost_vq_access_ok(&vs->vqs[index])) {
 			ret = -EFAULT;
-			goto err;
+			goto err_dev;
 		}
 	}
 	for (i = 0; i < VHOST_SCSI_MAX_TARGET; i++) {
@@ -860,10 +860,11 @@ static int vhost_scsi_clear_endpoint(
 		if (!tv_tpg)
 			continue;

+		mutex_lock(&tv_tpg->tv_tpg_mutex);
 		tv_tport = tv_tpg->tport;
 		if (!tv_tport) {
 			ret = -ENODEV;
-			goto err;
+			goto err_tpg;
 		}

 		if (strcmp(tv_tport->tport_name, t->vhost_wwpn)) {
@@ -872,16 +873,19 @@ static int vhost_scsi_clear_endpoint(
 				tv_tport->tport_name, tv_tpg->tport_tpgt,
 				t->vhost_wwpn, t->vhost_tpgt);
 			ret = -EINVAL;
-			goto err;
+			goto err_tpg;
 		}
 		tv_tpg->tv_tpg_vhost_count--;
 		vs->vs_tpg[target] = NULL;
 		vs->vs_endpoint = false;
+		mutex_unlock(&tv_tpg->tv_tpg_mutex);
 	}
 	mutex_unlock(&vs->dev.mutex);
 	return 0;

-err:
+err_tpg:
+	mutex_unlock(&tv_tpg->tv_tpg_mutex);
+err_dev:
 	mutex_unlock(&vs->dev.mutex);
 	return ret;
 }
--
1.8.1.4