From mboxrd@z Thu Jan 1 00:00:00 1970 From: Dmitry Torokhov Subject: Re: [PATCH] HID: hid-input: Fix accessing freed memory during driver unbind Date: Wed, 29 Jul 2015 10:46:19 -0700 Message-ID: <20150729174619.GC23178@dtor-ws> References: <1438042590-17719-1-git-send-email-k.kozlowski@samsung.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: Sender: stable-owner@vger.kernel.org To: Jiri Kosina Cc: Krzysztof Kozlowski , linux-input@vger.kernel.org, linux-kernel@vger.kernel.org, sre@kernel.org, linux-pm@vger.kernel.org, "H.J. Lu" , stable@vger.kernel.org List-Id: linux-input@vger.kernel.org On Wed, Jul 29, 2015 at 03:07:04PM +0200, Jiri Kosina wrote: > On Tue, 28 Jul 2015, Krzysztof Kozlowski wrote: > > > 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 > > Reported-by: H.J. Lu > > Fixes: 297d716f6260 ("power_supply: Change ownership from driver to core") > > Cc: > > Applied to for-4.2/upstream-fixes, thanks. Wait, what guarantees do we have that this is only called in probe() paths? Don't we allow hid_hw_start() be deferred to open() calls? In general we need to be careful with devm* conversions in core code. Thanks. -- Dmitry