vhost-vdpa: set v->config_ctx to NULL if eventfd_ctx_fdget() fails

In vhost_vdpa_set_config_call() if eventfd_ctx_fdget() fails the 'v->config_ctx' contains an error instead of a valid pointer. Since we consider 'v->config_ctx' valid if it is not NULL, we should set it to NULL in this case to avoid to use an invalid pointer in other functions such as vhost_vdpa_config_put(). Fixes: 776f395 ("vhost_vdpa: Support config interrupt in vdpa") Cc: [email protected] Cc: [email protected] Signed-off-by: Stefano Garzarella <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Michael S. Tsirkin <[email protected]> Acked-by: Jason Wang <[email protected]>
bignaux · Mar 14, 2021 · 0bde59c · 0bde59c
1 parent f6bbf00
commit 0bde59c
Showing 1 changed file with 6 additions and 2 deletions.
diff --git a/drivers/vhost/vdpa.c b/drivers/vhost/vdpa.c
@@ -331,8 +331,12 @@ static long vhost_vdpa_set_config_call(struct vhost_vdpa *v, u32 __user *argp)
 	if (!IS_ERR_OR_NULL(ctx))
 		eventfd_ctx_put(ctx);
 
-	if (IS_ERR(v->config_ctx))
-		return PTR_ERR(v->config_ctx);
+	if (IS_ERR(v->config_ctx)) {
+		long ret = PTR_ERR(v->config_ctx);
+
+		v->config_ctx = NULL;
+		return ret;
+	}
 
 	v->vdpa->config->set_config_cb(v->vdpa, &cb);