From 9ed51414aef6e59e832e2960f10766dce2d5b1a1 Mon Sep 17 00:00:00 2001 From: Dan Carpenter Date: Tue, 15 Nov 2022 16:16:43 +0300 Subject: drbd: use after free in drbd_create_device() MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit [ Upstream commit a7a1598189228b5007369a9622ccdf587be0730f ] The drbd_destroy_connection() frees the "connection" so use the _safe() iterator to prevent a use after free. Fixes: b6f85ef9538b ("drbd: Iterate over all connections") Signed-off-by: Dan Carpenter Reviewed-by: Christoph Böhmwalder Link: https://lore.kernel.org/r/Y3Jd5iZRbNQ9w6gm@kili Signed-off-by: Jens Axboe Signed-off-by: Sasha Levin --- drivers/block/drbd/drbd_main.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/block/drbd/drbd_main.c b/drivers/block/drbd/drbd_main.c index 407527ff6b1f..51450f7c81af 100644 --- a/drivers/block/drbd/drbd_main.c +++ b/drivers/block/drbd/drbd_main.c @@ -2720,7 +2720,7 @@ static int init_submitter(struct drbd_device *device) enum drbd_ret_code drbd_create_device(struct drbd_config_context *adm_ctx, unsigned int minor) { struct drbd_resource *resource = adm_ctx->resource; - struct drbd_connection *connection; + struct drbd_connection *connection, *n; struct drbd_device *device; struct drbd_peer_device *peer_device, *tmp_peer_device; struct gendisk *disk; @@ -2839,7 +2839,7 @@ enum drbd_ret_code drbd_create_device(struct drbd_config_context *adm_ctx, unsig out_idr_remove_vol: idr_remove(&connection->peer_devices, vnr); out_idr_remove_from_resource: - for_each_connection(connection, resource) { + for_each_connection_safe(connection, n, resource) { peer_device = idr_remove(&connection->peer_devices, vnr); if (peer_device) kref_put(&connection->kref, drbd_destroy_connection); -- cgit v1.2.3