TechPanelGM/kernel_xiaomi_sm8250
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

ACPI: battery: Fix possible crash when unregistering a battery hook

Browse Source 
[ Upstream commit 76959aff14a0012ad6b984ec7686d163deccdc16 ]

When a battery hook returns an error when adding a new battery, then
the battery hook is automatically unregistered.
However the battery hook provider cannot know that, so it will later
call battery_hook_unregister() on the already unregistered battery
hook, resulting in a crash.

Fix this by using the list head to mark already unregistered battery
hooks as already being unregistered so that they can be ignored by
battery_hook_unregister().

Fixes: fa93854f7a ("battery: Add the battery hooking API")
Signed-off-by: Armin Wolf <W_Armin@gmx.de>
Link: https://patch.msgid.link/20241001212835.341788-3-W_Armin@gmx.de
Cc: All applicable <stable@vger.kernel.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Armin Wolf
2024-10-01 23:28:34 +02:00
committed by Greg Kroah-Hartman
parent 079b8c72b4
commit 76fb2cbf01
1 changed files with 9 additions and 3 deletions
Download Patch File Download Diff File Expand all files Collapse all files

12
drivers/acpi/battery.c
View File

@@ -724,7 +724,7 @@ static void battery_hook_unregister_unlocked(struct acpi_battery_hook *hook)
list_for_each_entry(battery, &acpi_battery_list, list) { list_for_each_entry(battery, &acpi_battery_list, list) {
hook->remove_battery(battery->bat); hook->remove_battery(battery->bat);
} }
list_del(&hook->list); list_del_init(&hook->list);
pr_info("extension unregistered: %s\n", hook->name); pr_info("extension unregistered: %s\n", hook->name);
} }
@@ -732,7 +732,14 @@ static void battery_hook_unregister_unlocked(struct acpi_battery_hook *hook)
void battery_hook_unregister(struct acpi_battery_hook *hook) void battery_hook_unregister(struct acpi_battery_hook *hook)
{ {
mutex_lock(&hook_mutex); mutex_lock(&hook_mutex);
battery_hook_unregister_unlocked(hook); /*
* Ignore already unregistered battery hooks. This might happen
* if a battery hook was previously unloaded due to an error when
* adding a new battery.
*/
if (!list_empty(&hook->list))
battery_hook_unregister_unlocked(hook);
mutex_unlock(&hook_mutex); mutex_unlock(&hook_mutex);
} }
EXPORT_SYMBOL_GPL(battery_hook_unregister); EXPORT_SYMBOL_GPL(battery_hook_unregister);
@@ -742,7 +749,6 @@ void battery_hook_register(struct acpi_battery_hook *hook)
struct acpi_battery *battery; struct acpi_battery *battery;
mutex_lock(&hook_mutex); mutex_lock(&hook_mutex);
INIT_LIST_HEAD(&hook->list);
list_add(&hook->list, &battery_hook_list); list_add(&hook->list, &battery_hook_list);
/* /*
* Now that the driver is registered, we need * Now that the driver is registered, we need