Re: [PATCH] gpu/drm: fix potential memleak in error branch

On Tue, 16 Nov 2021, Bernard Zhao bernard@vivo.com wrote:

This patch try to fix potential memleak in error branch.

Please elaborate.

BR, Jani.

Signed-off-by: Bernard Zhao bernard@vivo.com

drivers/gpu/drm/drm_dp_mst_topology.c | 22 ++++++++++++++++------ 1 file changed, 16 insertions(+), 6 deletions(-)

diff --git a/drivers/gpu/drm/drm_dp_mst_topology.c b/drivers/gpu/drm/drm_dp_mst_topology.c index f3d79eda94bb..f73b180dee73 100644 --- a/drivers/gpu/drm/drm_dp_mst_topology.c +++ b/drivers/gpu/drm/drm_dp_mst_topology.c @@ -5501,7 +5501,10 @@ int drm_dp_mst_topology_mgr_init(struct drm_dp_mst_topology_mgr *mgr, int max_lane_count, int max_link_rate, int conn_base_id) {

• struct drm_dp_mst_topology_state *mst_state;

• struct drm_dp_mst_topology_state *mst_state = NULL;

• mgr->payloads = NULL;

• mgr->proposed_vcpis = NULL;

  mutex_init(&mgr->lock); mutex_init(&mgr->qlock);

@@ -5523,7 +5526,7 @@ int drm_dp_mst_topology_mgr_init(struct drm_dp_mst_topology_mgr *mgr, */ mgr->delayed_destroy_wq = alloc_ordered_workqueue("drm_dp_mst_wq", 0); if (mgr->delayed_destroy_wq == NULL)

• return -ENOMEM;
  

• goto out;
  
  

  INIT_WORK(&mgr->work, drm_dp_mst_link_probe_work); INIT_WORK(&mgr->tx_work, drm_dp_tx_work);

@@ -5539,18 +5542,18 @@ int drm_dp_mst_topology_mgr_init(struct drm_dp_mst_topology_mgr *mgr, mgr->conn_base_id = conn_base_id; if (max_payloads + 1 > sizeof(mgr->payload_mask) * 8 || max_payloads + 1 > sizeof(mgr->vcpi_mask) * 8)

• return -EINVAL;
  

• goto failed;
  

  mgr->payloads = kcalloc(max_payloads, sizeof(struct drm_dp_payload), GFP_KERNEL); if (!mgr->payloads)

• return -ENOMEM;
  

• goto failed;
  

  mgr->proposed_vcpis = kcalloc(max_payloads, sizeof(struct drm_dp_vcpi *), GFP_KERNEL); if (!mgr->proposed_vcpis)

• return -ENOMEM;
  

• goto failed;
  

  set_bit(0, &mgr->payload_mask);

  mst_state = kzalloc(sizeof(*mst_state), GFP_KERNEL); if (mst_state == NULL)

• return -ENOMEM;
  

• goto failed;
  
  

  mst_state->total_avail_slots = 63; mst_state->start_slot = 1;

@@ -5563,6 +5566,13 @@ int drm_dp_mst_topology_mgr_init(struct drm_dp_mst_topology_mgr *mgr, &drm_dp_mst_topology_state_funcs);

return 0;

+failed:

• kfree(mgr->proposed_vcpis);
• kfree(mgr->payloads);
• destroy_workqueue(mgr->delayed_destroy_wq);

+out:

• return -ENOMEM;

} EXPORT_SYMBOL(drm_dp_mst_topology_mgr_init);