From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 27DF58825 for ; Fri, 10 Mar 2023 14:56:15 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 81269C4339B; Fri, 10 Mar 2023 14:56:14 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1678460175; bh=6/OwhqZEoCnWMvzWTG606iTH0y7ZrDpAltPe5w4+44o=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=KhoLXK1gqcRvJ1pYGyphs3XhZhynIiiqPNnr/1QFkUEumoUfOnmn2AkCcoWeyJB2s uYp3fMx3zewhGh6M2DwZRyjSeWouUF9ur70q+6Ju+8P1/+yBi7Eqb5V3z3KZGBDShG IuzKM9DRreJVmkua9/+NVnR0SWnk7oOy27mP0RgE= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Pietro Borrello , Benjamin Tissoires , Sasha Levin Subject: [PATCH 5.10 217/529] HID: bigben: use spinlock to safely schedule workers Date: Fri, 10 Mar 2023 14:36:00 +0100 Message-Id: <20230310133815.059410037@linuxfoundation.org> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20230310133804.978589368@linuxfoundation.org> References: <20230310133804.978589368@linuxfoundation.org> User-Agent: quilt/0.67 Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit From: Pietro Borrello [ Upstream commit 76ca8da989c7d97a7f76c75d475fe95a584439d7 ] Use spinlocks to deal with workers introducing a wrapper bigben_schedule_work(), and several spinlock checks. Otherwise, bigben_set_led() may schedule bigben->worker after the structure has been freed, causing a use-after-free. Fixes: 4eb1b01de5b9 ("HID: hid-bigbenff: fix race condition for scheduled work during removal") Signed-off-by: Pietro Borrello Link: https://lore.kernel.org/r/20230125-hid-unregister-leds-v4-3-7860c5763c38@diag.uniroma1.it Signed-off-by: Benjamin Tissoires Signed-off-by: Sasha Levin --- drivers/hid/hid-bigbenff.c | 18 ++++++++++++------ 1 file changed, 12 insertions(+), 6 deletions(-) diff --git a/drivers/hid/hid-bigbenff.c b/drivers/hid/hid-bigbenff.c index b98c5f31c184b..9d6560db762b1 100644 --- a/drivers/hid/hid-bigbenff.c +++ b/drivers/hid/hid-bigbenff.c @@ -185,6 +185,15 @@ struct bigben_device { struct work_struct worker; }; +static inline void bigben_schedule_work(struct bigben_device *bigben) +{ + unsigned long flags; + + spin_lock_irqsave(&bigben->lock, flags); + if (!bigben->removed) + schedule_work(&bigben->worker); + spin_unlock_irqrestore(&bigben->lock, flags); +} static void bigben_worker(struct work_struct *work) { @@ -197,9 +206,6 @@ static void bigben_worker(struct work_struct *work) u32 len; unsigned long flags; - if (bigben->removed) - return; - buf = hid_alloc_report_buf(bigben->report, GFP_KERNEL); if (!buf) return; @@ -285,7 +291,7 @@ static int hid_bigben_play_effect(struct input_dev *dev, void *data, bigben->work_ff = true; spin_unlock_irqrestore(&bigben->lock, flags); - schedule_work(&bigben->worker); + bigben_schedule_work(bigben); } return 0; @@ -320,7 +326,7 @@ static void bigben_set_led(struct led_classdev *led, if (work) { bigben->work_led = true; - schedule_work(&bigben->worker); + bigben_schedule_work(bigben); } return; } @@ -450,7 +456,7 @@ static int bigben_probe(struct hid_device *hid, bigben->left_motor_force = 0; bigben->work_led = true; bigben->work_ff = true; - schedule_work(&bigben->worker); + bigben_schedule_work(bigben); hid_info(hid, "LED and force feedback support for BigBen gamepad\n"); -- 2.39.2