-----邮件原件----- 发件人: bernard@vivo.com bernard@vivo.com 代表 Jani Nikula 发送时间: 2022年1月4日 19:25 收件人: 赵军奎 bernard@vivo.com; Maarten Lankhorst maarten.lankhorst@linux.intel.com; Maxime Ripard mripard@kernel.org; Thomas Zimmermann tzimmermann@suse.de; David Airlie airlied@linux.ie; Daniel Vetter daniel@ffwll.ch; dri-devel@lists.freedesktop.org; linux-kernel@vger.kernel.org 主题: Re: 答复: [PATCH] gpu/drm: fix potential memleak in error branch
On Tue, 04 Jan 2022, 赵军奎 bernard@vivo.com wrote:
-----邮件原件----- 发件人: bernard@vivo.com bernard@vivo.com 代表 Jani Nikula 发送时间: 2021年12月31日 19:09 收件人: 赵军奎 bernard@vivo.com; Maarten Lankhorst maarten.lankhorst@linux.intel.com; Maxime Ripard mripard@kernel.org; Thomas Zimmermann tzimmermann@suse.de; David Airlie airlied@linux.ie; Daniel Vetter daniel@ffwll.ch; dri-devel@lists.freedesktop.org; linux-kernel@vger.kernel.org 抄送: 赵军奎 bernard@vivo.com 主题: 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.
Hi Jani:
This patch try to fix potential memleak in error branch. For example: nv50_sor_create ->nv50_mstm_new-> drm_dp_mst_topology_mgr_init In function drm_dp_mst_topology_mgr_init, there are five error branches, error branch just return error code, no free called. And we see that the caller didn`t do the drm_dp_mst_topology_mgr_destroy job. I am not sure if there some gap, I think this may bring in the risk of memleak issue. Thanks!
This should be part of the commit message.
Hi Jani:
Thanks for your comments, I will resubmit this patch!
BR//Bernard
BR//Bernard
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;
This is superfluous.
Other than that,
Reviewed-by: Jani Nikula jani.nikula@intel.com
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;
return -ENOMEM;
goto failed;
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);
-- Jani Nikula, Intel Open Source Graphics Center
-- Jani Nikula, Intel Open Source Graphics Center