| Message ID | 20240419113637.25745-1-amishin@t-argos.ru (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | drm: bridge: cdns-mhdp8546: Fix missing mutex unlock on error path | expand |
On Fri, Apr 19, 2024 at 02:36:37PM +0300, Aleksandr Mishin wrote: > In cdns_mhdp_atomic_enable(), there is an error return on failure of > drm_mode_duplicate() which leads to the mutex remaining locked. > Add a mutex unlock call. > > Found by Linux Verification Center (linuxtesting.org) with SVACE. > > Fixes: 935a92a1c400 ("drm: bridge: cdns-mhdp8546: Fix possible null pointer dereference") > Signed-off-by: Aleksandr Mishin <amishin@t-argos.ru> > --- > This patch is against drm-misc-next branch of drm-misc repo. > > drivers/gpu/drm/bridge/cadence/cdns-mhdp8546-core.c | 6 ++++-- > 1 file changed, 4 insertions(+), 2 deletions(-) > > Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
…
> Add a mutex unlock call.
How do you think about a wording variant like the following?
Extend the exception handling so that the missed mutex_unlock() call
will be performed finally.
Regards,
Markus
diff --git a/drivers/gpu/drm/bridge/cadence/cdns-mhdp8546-core.c b/drivers/gpu/drm/bridge/cadence/cdns-mhdp8546-core.c index 8a91ef0ae065..65a4bd09d9c6 100644 --- a/drivers/gpu/drm/bridge/cadence/cdns-mhdp8546-core.c +++ b/drivers/gpu/drm/bridge/cadence/cdns-mhdp8546-core.c @@ -2059,8 +2059,10 @@ static void cdns_mhdp_atomic_enable(struct drm_bridge *bridge, mhdp_state = to_cdns_mhdp_bridge_state(new_state); mhdp_state->current_mode = drm_mode_duplicate(bridge->dev, mode); - if (!mhdp_state->current_mode) - return; + if (!mhdp_state->current_mode) { + ret = -EINVAL; + goto out; + } drm_mode_set_name(mhdp_state->current_mode);
In cdns_mhdp_atomic_enable(), there is an error return on failure of drm_mode_duplicate() which leads to the mutex remaining locked. Add a mutex unlock call. Found by Linux Verification Center (linuxtesting.org) with SVACE. Fixes: 935a92a1c400 ("drm: bridge: cdns-mhdp8546: Fix possible null pointer dereference") Signed-off-by: Aleksandr Mishin <amishin@t-argos.ru> --- This patch is against drm-misc-next branch of drm-misc repo. drivers/gpu/drm/bridge/cadence/cdns-mhdp8546-core.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-)