patch "usb: typec: tcpci: Don't skip cleanup in .remove() on error" added to usb-linus

patch "usb: typec: tcpci: Don't skip cleanup in .remove() on error" added to usb-linus

[gregkh]

This is a note to let you know that I've just added the patch titled

    usb: typec: tcpci: Don't skip cleanup in .remove() on error

to my usb git tree which can be found at
    git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git
in the usb-linus branch.

The patch will show up in the next release of the linux-next tree
(usually sometime within the next 24 hours during the week.)

The patch will hopefully also be merged in Linus's tree for the
next -rc kernel release.

If you have any questions about this process, please let me know.


From bbc126ae381cf0a27822c1f822d0aeed74cc40d9 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Uwe=20Kleine-K=C3=B6nig?= <u.kleine-koenig@pengutronix.de>
Date: Mon, 2 May 2022 10:04:56 +0200
Subject: usb: typec: tcpci: Don't skip cleanup in .remove() on error
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Returning an error value in an i2c remove callback results in an error
message being emitted by the i2c core, but otherwise it doesn't make a
difference. The device goes away anyhow and the devm cleanups are
called.

In this case the remove callback even returns early without stopping the
tcpm worker thread and various timers. A work scheduled on the work
queue, or a firing timer after tcpci_remove() returned probably results
in a use-after-free situation because the regmap and driver data were
freed. So better make sure that tcpci_unregister_port() is called even
if disabling the irq failed.

Also emit a more specific error message instead of the i2c core's
"remove failed (EIO), will be ignored" and return 0 to suppress the
core's warning.

This patch is (also) a preparation for making i2c remove callbacks
return void.

Fixes: 3ba76256fc4e ("usb: typec: tcpci: mask event interrupts when remove driver")
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Cc: stable <stable@vger.kernel.org>
Acked-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20220502080456.21568-1-u.kleine-koenig@pengutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 drivers/usb/typec/tcpm/tcpci.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/usb/typec/tcpm/tcpci.c b/drivers/usb/typec/tcpm/tcpci.c
index e07d26a3cd8e..f33e08eb7670 100644
--- a/drivers/usb/typec/tcpm/tcpci.c
+++ b/drivers/usb/typec/tcpm/tcpci.c
@@ -877,7 +877,7 @@ static int tcpci_remove(struct i2c_client *client)
 	/* Disable chip interrupts before unregistering port */
 	err = tcpci_write16(chip->tcpci, TCPC_ALERT_MASK, 0);
 	if (err < 0)
-		return err;
+		dev_warn(&client->dev, "Failed to disable irqs (%pe)\n", ERR_PTR(err));
 
 	tcpci_unregister_port(chip->tcpci);
 
-- 
2.36.0