From 0621809e37936e7c2b3eac9165cf2aad7f9189eb Mon Sep 17 00:00:00 2001 From: Krzysztof Kozlowski Date: Mon, 3 Aug 2015 14:57:30 +0900 Subject: [PATCH] HID: hid-input: Fix accessing freed memory during device disconnect 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() this memory is freed and the driver cannot access these members. Fix this by storing the pointer to internal description of battery in a local variable before calling power_supply_unregister(), so the pointer remains valid. Signed-off-by: Krzysztof Kozlowski Reported-by: H.J. Lu Fixes: 297d716f6260 ("power_supply: Change ownership from driver to core") Cc: Reviewed-by: Dmitry Torokhov Signed-off-by: Jiri Kosina --- drivers/hid/hid-input.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) diff --git a/drivers/hid/hid-input.c b/drivers/hid/hid-input.c index 3511bbaba505..e3c63640df73 100644 --- a/drivers/hid/hid-input.c +++ b/drivers/hid/hid-input.c @@ -462,12 +462,15 @@ out: static void hidinput_cleanup_battery(struct hid_device *dev) { + const struct power_supply_desc *psy_desc; + if (!dev->battery) return; + psy_desc = dev->battery->desc; power_supply_unregister(dev->battery); - kfree(dev->battery->desc->name); - kfree(dev->battery->desc); + kfree(psy_desc->name); + kfree(psy_desc); dev->battery = NULL; } #else /* !CONFIG_HID_BATTERY_STRENGTH */ -- 2.34.1