diff options
| author | José Roberto de Souza <jose.souza@intel.com> | 2020-01-29 15:24:48 -0800 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2020-02-19 19:54:07 +0100 |
| commit | f0d2fe7a8595571986df9703617c5e1d91766f88 (patch) | |
| tree | 35b6d07ab0ab78af5811c0d283ac59a7509802f0 | |
| parent | c578f31bba29d2c6a97d2ad279ae3cd261dcc786 (diff) | |
| download | linux-f0d2fe7a8595571986df9703617c5e1d91766f88.tar.gz linux-f0d2fe7a8595571986df9703617c5e1d91766f88.tar.bz2 linux-f0d2fe7a8595571986df9703617c5e1d91766f88.zip | |
drm/mst: Fix possible NULL pointer dereference in drm_dp_mst_process_up_req()
commit 8ccb5bf7619c6523e7a4384a84b72e7be804298c upstream.
According to DP specification, DP_SINK_EVENT_NOTIFY is also a
broadcast message but as this function only handles
DP_CONNECTION_STATUS_NOTIFY I will only make the static
analyzer that caught this issue happy by not calling
drm_dp_get_mst_branch_device_by_guid() with a NULL guid, causing
drm_dp_mst_process_up_req() to return in the "if (!mstb)" right
bellow.
Fixes: 9408cc94eb04 ("drm/dp_mst: Handle UP requests asynchronously")
Cc: Lyude Paul <lyude@redhat.com>
Cc: Sean Paul <sean@poorly.run>
Cc: <stable@vger.kernel.org> # v5.5+
Signed-off-by: José Roberto de Souza <jose.souza@intel.com>
[added cc to stable]
Signed-off-by: Lyude Paul <lyude@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200129232448.84704-1-jose.souza@intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | drivers/gpu/drm/drm_dp_mst_topology.c | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/drivers/gpu/drm/drm_dp_mst_topology.c b/drivers/gpu/drm/drm_dp_mst_topology.c index 141ba31cf548..6cd90cb4b6b1 100644 --- a/drivers/gpu/drm/drm_dp_mst_topology.c +++ b/drivers/gpu/drm/drm_dp_mst_topology.c @@ -3772,7 +3772,8 @@ drm_dp_mst_process_up_req(struct drm_dp_mst_topology_mgr *mgr, else if (msg->req_type == DP_RESOURCE_STATUS_NOTIFY) guid = msg->u.resource_stat.guid; - mstb = drm_dp_get_mst_branch_device_by_guid(mgr, guid); + if (guid) + mstb = drm_dp_get_mst_branch_device_by_guid(mgr, guid); } else { mstb = drm_dp_get_mst_branch_device(mgr, hdr->lct, hdr->rad); } |