This is a note to let you know that I've just added the patch titled drm: fix mutex leak in drm_dp_get_mst_branch_device to the 4.2-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: drm-fix-mutex-leak-in-drm_dp_get_mst_branch_device.patch and it can be found in the queue-4.2 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From 30730c7f5943b3beace1e29f7f1476e05de3da14 Mon Sep 17 00:00:00 2001 From: Adam Richter <adamrichter4@xxxxxxxxx> Date: Fri, 16 Oct 2015 03:33:02 -0700 Subject: drm: fix mutex leak in drm_dp_get_mst_branch_device From: Adam Richter <adamrichter4@xxxxxxxxx> commit 30730c7f5943b3beace1e29f7f1476e05de3da14 upstream. 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@xxxxxxxxx> Signed-off-by: Daniel Vetter <daniel.vetter@xxxxxxxx> Signed-off-by: Dave Airlie <airlied@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/gpu/drm/drm_dp_mst_topology.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) --- a/drivers/gpu/drm/drm_dp_mst_topology.c +++ b/drivers/gpu/drm/drm_dp_mst_topology.c @@ -1193,17 +1193,18 @@ static struct drm_dp_mst_branch *drm_dp_ 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; } Patches currently in stable-queue which might be from adamrichter4@xxxxxxxxx are queue-4.2/drm-fix-mutex-leak-in-drm_dp_get_mst_branch_device.patch -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html