From bb197cebd5443bc71d82e218ced92f1db540c2d4 Mon Sep 17 00:00:00 2001 From: RD Babiera Date: Thu, 7 Mar 2024 22:09:02 +0000 Subject: [PATCH] UPSTREAM: usb: typec: altmodes/displayport: create sysfs nodes as driver's default device attribute group The DisplayPort driver's sysfs nodes may be present to the userspace before typec_altmode_set_drvdata() completes in dp_altmode_probe. This means that a sysfs read can trigger a NULL pointer error by deferencing dp->hpd in hpd_show or dp->lock in pin_assignment_show, as dev_get_drvdata() returns NULL in those cases. Remove manual sysfs node creation in favor of adding attribute group as default for devices bound to the driver. The ATTRIBUTE_GROUPS() macro is not used here otherwise the path to the sysfs nodes is no longer compliant with the ABI. Fixes: 0e3bb7d6894d ("usb: typec: Add driver for DisplayPort alternate mode") Cc: stable@vger.kernel.org Signed-off-by: RD Babiera Link: https://lore.kernel.org/r/20240229001101.3889432-2-rdbabiera@google.com Signed-off-by: Greg Kroah-Hartman Bug: 313517804 (cherry picked from commit 165376f6b23e9a779850e750fb2eb06622e5a531) Signed-off-by: RD Babiera (cherry picked from https://android-review.googlesource.com/q/commit:884fea555f0af00dee9fefefa5bb38eb4ed251b5) Merged-In: I13aaa956ff2b37e29eb0d90bbac0b7e1ac969b80 Change-Id: I13aaa956ff2b37e29eb0d90bbac0b7e1ac969b80 --- drivers/usb/typec/altmodes/displayport.c | 18 +++++++++--------- 1 file changed, 9 insertions(+), 9 deletions(-) diff --git a/drivers/usb/typec/altmodes/displayport.c b/drivers/usb/typec/altmodes/displayport.c index 1d225b02e90a..6d94c291fb5e 100644 --- a/drivers/usb/typec/altmodes/displayport.c +++ b/drivers/usb/typec/altmodes/displayport.c @@ -552,16 +552,21 @@ static ssize_t hpd_show(struct device *dev, struct device_attribute *attr, char } static DEVICE_ATTR_RO(hpd); -static struct attribute *dp_altmode_attrs[] = { +static struct attribute *displayport_attrs[] = { &dev_attr_configuration.attr, &dev_attr_pin_assignment.attr, &dev_attr_hpd.attr, NULL }; -static const struct attribute_group dp_altmode_group = { +static const struct attribute_group displayport_group = { .name = "displayport", - .attrs = dp_altmode_attrs, + .attrs = displayport_attrs, +}; + +static const struct attribute_group *displayport_groups[] = { + &displayport_group, + NULL, }; int dp_altmode_probe(struct typec_altmode *alt) @@ -569,7 +574,6 @@ int dp_altmode_probe(struct typec_altmode *alt) const struct typec_altmode *port = typec_altmode_get_partner(alt); struct fwnode_handle *fwnode; struct dp_altmode *dp; - int ret; /* FIXME: Port can only be DFP_U. */ @@ -580,10 +584,6 @@ int dp_altmode_probe(struct typec_altmode *alt) DP_CAP_PIN_ASSIGN_DFP_D(alt->vdo))) return -ENODEV; - ret = sysfs_create_group(&alt->dev.kobj, &dp_altmode_group); - if (ret) - return ret; - dp = devm_kzalloc(&alt->dev, sizeof(*dp), GFP_KERNEL); if (!dp) return -ENOMEM; @@ -614,7 +614,6 @@ void dp_altmode_remove(struct typec_altmode *alt) { struct dp_altmode *dp = typec_altmode_get_drvdata(alt); - sysfs_remove_group(&alt->dev.kobj, &dp_altmode_group); cancel_work_sync(&dp->work); if (dp->connector_fwnode) { @@ -639,6 +638,7 @@ static struct typec_altmode_driver dp_altmode_driver = { .driver = { .name = "typec_displayport", .owner = THIS_MODULE, + .dev_groups = displayport_groups, }, }; module_typec_altmode_driver(dp_altmode_driver);