mfd: core: Add locking around 'mfd_of_node_list'

[ Upstream commit 20117c92bc ]

Manipulating a list in the kernel isn't safe without some sort of
mutual exclusion. Add a mutex any time we access / modify
'mfd_of_node_list' to prevent possible crashes.

Cc: stable@vger.kernel.org
Fixes: 466a62d764 ("mfd: core: Make a best effort attempt to match devices with the correct of_nodes")
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Link: https://patch.msgid.link/20251210113002.1.I6ceaca2cfb7eb25737012b166671f516696be4fd@changeid
Signed-off-by: Lee Jones <lee@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Douglas Anderson
2026-03-04 07:20:48 -05:00
committed by Sasha Levin
parent ead67d0378
commit dcfa679bba
+22 -14
View File
@@ -22,6 +22,7 @@
#include <linux/regulator/consumer.h>
static LIST_HEAD(mfd_of_node_list);
static DEFINE_MUTEX(mfd_of_node_mutex);
struct mfd_of_node_entry {
struct list_head list;
@@ -132,9 +133,11 @@ static int mfd_match_of_node_to_dev(struct platform_device *pdev,
u64 of_node_addr;
/* Skip if OF node has previously been allocated to a device */
list_for_each_entry(of_entry, &mfd_of_node_list, list)
if (of_entry->np == np)
return -EAGAIN;
scoped_guard(mutex, &mfd_of_node_mutex) {
list_for_each_entry(of_entry, &mfd_of_node_list, list)
if (of_entry->np == np)
return -EAGAIN;
}
if (!cell->use_of_reg)
/* No of_reg defined - allocate first free compatible match */
@@ -159,7 +162,8 @@ allocate_of_node:
of_entry->dev = &pdev->dev;
of_entry->np = np;
list_add_tail(&of_entry->list, &mfd_of_node_list);
scoped_guard(mutex, &mfd_of_node_mutex)
list_add_tail(&of_entry->list, &mfd_of_node_list);
pdev->dev.of_node = np;
pdev->dev.fwnode = &np->fwnode;
@@ -316,11 +320,13 @@ fail_res_conflict:
if (cell->swnode)
device_remove_software_node(&pdev->dev);
fail_of_entry:
list_for_each_entry_safe(of_entry, tmp, &mfd_of_node_list, list)
if (of_entry->dev == &pdev->dev) {
list_del(&of_entry->list);
kfree(of_entry);
}
scoped_guard(mutex, &mfd_of_node_mutex) {
list_for_each_entry_safe(of_entry, tmp, &mfd_of_node_list, list)
if (of_entry->dev == &pdev->dev) {
list_del(&of_entry->list);
kfree(of_entry);
}
}
fail_alias:
regulator_bulk_unregister_supply_alias(&pdev->dev,
cell->parent_supplies,
@@ -390,11 +396,13 @@ static int mfd_remove_devices_fn(struct device *dev, void *data)
if (cell->swnode)
device_remove_software_node(&pdev->dev);
list_for_each_entry_safe(of_entry, tmp, &mfd_of_node_list, list)
if (of_entry->dev == &pdev->dev) {
list_del(&of_entry->list);
kfree(of_entry);
}
scoped_guard(mutex, &mfd_of_node_mutex) {
list_for_each_entry_safe(of_entry, tmp, &mfd_of_node_list, list)
if (of_entry->dev == &pdev->dev) {
list_del(&of_entry->list);
kfree(of_entry);
}
}
regulator_bulk_unregister_supply_alias(dev, cell->parent_supplies,
cell->num_parent_supplies);