HID: core/input: Fix accessing freed memory during driver unbind
During unbinding the driver was dereferencing a pointer to memory
already freed by power_supply_unregister().
Driver was freeing its internal description of battery through pointers
stored in power_supply structure. However, because the core owns the
power supply instance, after calling power_supply_unregister() the
driver cannot access these members.
Fix this by using resource-managed allocations so internal data will be
freed by pointers stored in resource-managed core.
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Reported-by: H.J. Lu <hjl.tools@gmail.com>
Fixes: 297d716f6260 ("power_supply: Change ownership from driver to core")
Cc: <stable@vger.kernel.org>
Signed-off-by: Jiri Kosina <jkosina@suse.com>
diff --git a/drivers/hid/hid-input.c b/drivers/hid/hid-input.c
index 3511bbab..6e3d7fd 100644
--- a/drivers/hid/hid-input.c
+++ b/drivers/hid/hid-input.c
@@ -408,15 +408,14 @@
if (dev->battery != NULL)
goto out; /* already initialized? */
- psy_desc = kzalloc(sizeof(*psy_desc), GFP_KERNEL);
+ psy_desc = devm_kzalloc(&dev->dev, sizeof(*psy_desc), GFP_KERNEL);
if (psy_desc == NULL)
goto out;
- psy_desc->name = kasprintf(GFP_KERNEL, "hid-%s-battery", dev->uniq);
- if (psy_desc->name == NULL) {
- kfree(psy_desc);
+ psy_desc->name = devm_kasprintf(&dev->dev, GFP_KERNEL,
+ "hid-%s-battery", dev->uniq);
+ if (psy_desc->name == NULL)
goto out;
- }
psy_desc->type = POWER_SUPPLY_TYPE_BATTERY;
psy_desc->properties = hidinput_battery_props;
@@ -449,8 +448,6 @@
if (IS_ERR(dev->battery)) {
hid_warn(dev, "can't register power supply: %ld\n",
PTR_ERR(dev->battery));
- kfree(psy_desc->name);
- kfree(psy_desc);
dev->battery = NULL;
} else {
power_supply_powers(dev->battery, &dev->dev);
@@ -466,8 +463,6 @@
return;
power_supply_unregister(dev->battery);
- kfree(dev->battery->desc->name);
- kfree(dev->battery->desc);
dev->battery = NULL;
}
#else /* !CONFIG_HID_BATTERY_STRENGTH */
