This is a note to let you know that I've just added the patch titled
usb: ucsi: Fix ucsi->connector race
to the 6.2-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
usb-ucsi-fix-ucsi-connector-race.patch
and it can be found in the queue-6.2 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 0482c34ec6f8557e06cd0f8e2d0e20e8ede6a22c Mon Sep 17 00:00:00 2001
From: Hans de Goede <hdegoede@xxxxxxxxxx>
Date: Wed, 8 Mar 2023 16:42:43 +0100
Subject: usb: ucsi: Fix ucsi->connector race
From: Hans de Goede <hdegoede@xxxxxxxxxx>
commit 0482c34ec6f8557e06cd0f8e2d0e20e8ede6a22c upstream.
ucsi_init() which runs from a workqueue sets ucsi->connector and
on an error will clear it again.
ucsi->connector gets dereferenced by ucsi_resume(), this checks for
ucsi->connector being NULL in case ucsi_init() has not finished yet;
or in case ucsi_init() has failed.
ucsi_init() setting ucsi->connector and then clearing it again on
an error creates a race where the check in ucsi_resume() may pass,
only to have ucsi->connector free-ed underneath it when ucsi_init()
hits an error.
Fix this race by making ucsi_init() store the connector array in
a local variable and only assign it to ucsi->connector on success.
Fixes: bdc62f2bae8f ("usb: typec: ucsi: Simplified registration and I/O API")
Cc: stable@xxxxxxxxxxxxxxx
Reviewed-by: Heikki Krogerus <heikki.krogerus@xxxxxxxxxxxxxxx>
Signed-off-by: Hans de Goede <hdegoede@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20230308154244.722337-3-hdegoede@xxxxxxxxxx
Signed-off-by: Joakim Tjernlund <joakim.tjernlund@xxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/usb/typec/ucsi/ucsi.c | 22 +++++++++-------------
1 file changed, 9 insertions(+), 13 deletions(-)
--- a/drivers/usb/typec/ucsi/ucsi.c
+++ b/drivers/usb/typec/ucsi/ucsi.c
@@ -1039,9 +1039,8 @@ static struct fwnode_handle *ucsi_find_f
return NULL;
}
-static int ucsi_register_port(struct ucsi *ucsi, int index)
+static int ucsi_register_port(struct ucsi *ucsi, struct ucsi_connector *con)
{
- struct ucsi_connector *con = &ucsi->connector[index];
struct typec_capability *cap = &con->typec_cap;
enum typec_accessory *accessory = cap->accessory;
enum usb_role u_role = USB_ROLE_NONE;
@@ -1062,7 +1061,6 @@ static int ucsi_register_port(struct ucs
init_completion(&con->complete);
mutex_init(&con->lock);
INIT_LIST_HEAD(&con->partner_tasks);
- con->num = index + 1;
con->ucsi = ucsi;
cap->fwnode = ucsi_find_fwnode(con);
@@ -1204,7 +1202,7 @@ out_unlock:
*/
static int ucsi_init(struct ucsi *ucsi)
{
- struct ucsi_connector *con;
+ struct ucsi_connector *con, *connector;
u64 command, ntfy;
int ret;
int i;
@@ -1235,16 +1233,16 @@ static int ucsi_init(struct ucsi *ucsi)
}
/* Allocate the connectors. Released in ucsi_unregister() */
- ucsi->connector = kcalloc(ucsi->cap.num_connectors + 1,
- sizeof(*ucsi->connector), GFP_KERNEL);
- if (!ucsi->connector) {
+ connector = kcalloc(ucsi->cap.num_connectors + 1, sizeof(*connector), GFP_KERNEL);
+ if (!connector) {
ret = -ENOMEM;
goto err_reset;
}
/* Register all connectors */
for (i = 0; i < ucsi->cap.num_connectors; i++) {
- ret = ucsi_register_port(ucsi, i);
+ connector[i].num = i + 1;
+ ret = ucsi_register_port(ucsi, &connector[i]);
if (ret)
goto err_unregister;
}
@@ -1256,11 +1254,12 @@ static int ucsi_init(struct ucsi *ucsi)
if (ret < 0)
goto err_unregister;
+ ucsi->connector = connector;
ucsi->ntfy = ntfy;
return 0;
err_unregister:
- for (con = ucsi->connector; con->port; con++) {
+ for (con = connector; con->port; con++) {
ucsi_unregister_partner(con);
ucsi_unregister_altmodes(con, UCSI_RECIPIENT_CON);
ucsi_unregister_port_psy(con);
@@ -1269,10 +1268,7 @@ err_unregister:
typec_unregister_port(con->port);
con->port = NULL;
}
-
- kfree(ucsi->connector);
- ucsi->connector = NULL;
-
+ kfree(connector);
err_reset:
memset(&ucsi->cap, 0, sizeof(ucsi->cap));
ucsi_reset_ppm(ucsi);
Patches currently in stable-queue which might be from hdegoede@xxxxxxxxxx are
queue-6.2/acpi-x86-introduce-an-acpi_quirk_skip_gpio_event_han.patch
queue-6.2/platform-x86-think-lmi-add-missing-type-attribute.patch
queue-6.2/input-focaltech-use-explicitly-signed-char-type.patch
queue-6.2/input-i8042-add-quirk-for-fujitsu-lifebook-a574-h.patch
queue-6.2/drm-nouveau-kms-fix-backlight-registration.patch
queue-6.2/platform-x86-ideapad-laptop-stop-sending-key_touchpad_toggle.patch
queue-6.2/platform-x86-think-lmi-use-correct-possible_values-d.patch
queue-6.2/acpi-x86-add-skip-i2c-clients-quirk-for-acer-iconia-.patch
queue-6.2/usb-ucsi-fix-ucsi-connector-race.patch
queue-6.2/acpi-x86-add-skip-i2c-clients-quirk-for-lenovo-yoga-.patch
queue-6.2/platform-x86-think-lmi-add-possible_values-for-think.patch
queue-6.2/input-goodix-add-lenovo-yoga-book-x90f-to-nine_bytes_report-dmi-table.patch
queue-6.2/platform-x86-intel-pmc-alder-lake-pch-slp_s0_residen.patch
queue-6.2/platform-surface-aggregator-add-missing-fwnode_handl.patch
queue-6.2/platform-x86-think-lmi-only-display-possible_values-.patch
