diff options
| author |   Won Chung <wonchung@google.com> | 2022-04-18 17:59:31 +0000 |
|---|---|---|
| committer |   Mika Westerberg <mika.westerberg@linux.intel.com> | 2022-04-29 12:17:22 +0300 |
| commit | 84d4333c1e28cedfad37c5347b4a94a3565a454f (patch) | |
| tree | dbf9dac7d5fbc5af6c119d1bad180a8600a29c4b /drivers/misc/mei | |
| parent | thunderbolt: Use different lane for second DisplayPort tunnel (diff) | |
| download | linux-dev-84d4333c1e28cedfad37c5347b4a94a3565a454f.tar.xz linux-dev-84d4333c1e28cedfad37c5347b4a94a3565a454f.zip | |
misc/mei: Add NULL check to component match callback functions
Currently, component_match callback functions used in mei refers to the
driver name, assuming that the component device being matched has a
driver bound. It can cause a NULL pointer dereference when a device
without a driver bound registers a component. This is due to the nature
of the component framework where all registered components are matched
in any component_match callback functions. So even if a component is
registered by a totally irrelevant device, that component is also
shared to these callbacks for i915 driver.
To prevent totally irrelevant device being matched for i915 and causing
a NULL pointer dereference for checking driver name, add a NULL check on
dev->driver to check if there is a driver bound before checking the
driver name.
In the future, the string compare on the driver name, "i915" may need to
be refactored too.
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Reviewed-by: Prashant Malani <pmalani@chromium.org>
Signed-off-by: Won Chung <wonchung@google.com>
Acked-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Diffstat (limited to 'drivers/misc/mei')
| -rw-r--r-- | drivers/misc/mei/hdcp/mei_hdcp.c | 2 | ||||
| -rw-r--r-- | drivers/misc/mei/pxp/mei_pxp.c | 2 |
2 files changed, 2 insertions, 2 deletions
diff --git a/drivers/misc/mei/hdcp/mei_hdcp.c b/drivers/misc/mei/hdcp/mei_hdcp.c index ec2a4fce8581..e889a8bd7ac8 100644 --- a/drivers/misc/mei/hdcp/mei_hdcp.c +++ b/drivers/misc/mei/hdcp/mei_hdcp.c @@ -784,7 +784,7 @@ static int mei_hdcp_component_match(struct device *dev, int subcomponent, { struct device *base = data; - if (strcmp(dev->driver->name, "i915") || + if (!dev->driver || strcmp(dev->driver->name, "i915") || subcomponent != I915_COMPONENT_HDCP) return 0; diff --git a/drivers/misc/mei/pxp/mei_pxp.c b/drivers/misc/mei/pxp/mei_pxp.c index f7380d387bab..5c39457e3f53 100644 --- a/drivers/misc/mei/pxp/mei_pxp.c +++ b/drivers/misc/mei/pxp/mei_pxp.c @@ -131,7 +131,7 @@ static int mei_pxp_component_match(struct device *dev, int subcomponent, { struct device *base = data; - if (strcmp(dev->driver->name, "i915") || + if (!dev->driver || strcmp(dev->driver->name, "i915") || subcomponent != I915_COMPONENT_PXP) return 0; |