diff options
author | Adam Richter <adamrichter4@gmail.com> | 2015-10-16 10:33:02 (GMT) |
---|---|---|
committer | Dave Airlie <airlied@redhat.com> | 2015-10-21 22:29:08 (GMT) |
commit | 30730c7f5943b3beace1e29f7f1476e05de3da14 (patch) | |
tree | 2420503336aa1afaca73ad9be3b06e79e9aef407 | |
parent | 1099f86044111e9a7807f09523e42d4c9d0fb781 (diff) | |
download | linux-30730c7f5943b3beace1e29f7f1476e05de3da14.tar.xz |
drm: fix mutex leak in drm_dp_get_mst_branch_device
In Linux 4.3-rc5, there is an error case in drm_dp_get_branch_device
that returns without releasing mgr->lock, resulting a spew of kernel
messages about a kernel work function possibly having leaked a mutex
and presumably more serious adverse consequences later. This patch
changes the error to "goto out" to unlock the mutex before returning.
[airlied: grabbed from drm-next as it fixes something we've seen]
Signed-off-by: Adam J. Richter <adam_richter2004@yahoo.com>
Cc: stable@vger.kernel.org
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Dave Airlie <airlied@redhat.com>
-rw-r--r-- | drivers/gpu/drm/drm_dp_mst_topology.c | 7 |
1 files changed, 4 insertions, 3 deletions
diff --git a/drivers/gpu/drm/drm_dp_mst_topology.c b/drivers/gpu/drm/drm_dp_mst_topology.c index 5bca390..809959d 100644 --- a/drivers/gpu/drm/drm_dp_mst_topology.c +++ b/drivers/gpu/drm/drm_dp_mst_topology.c @@ -1194,17 +1194,18 @@ static struct drm_dp_mst_branch *drm_dp_get_mst_branch_device(struct drm_dp_mst_ list_for_each_entry(port, &mstb->ports, next) { if (port->port_num == port_num) { - if (!port->mstb) { + mstb = port->mstb; + if (!mstb) { DRM_ERROR("failed to lookup MSTB with lct %d, rad %02x\n", lct, rad[0]); - return NULL; + goto out; } - mstb = port->mstb; break; } } } kref_get(&mstb->kref); +out: mutex_unlock(&mgr->lock); return mstb; } |