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| author | Armin Wolf <W_Armin@gmx.de> | 2024-10-01 23:28:34 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2024-10-10 11:58:06 +0200 |
| commit | ce31847f109c3a5b2abdd19d7bcaafaacfde53de (patch) | |
| tree | 0054d41fc4ab30da15cf73415f7de5bfe61ad2ca /drivers/acpi | |
| parent | 2deeb3c748dac6efea25395ed107a791c72e7c04 (diff) | |
| download | linux-ce31847f109c3a5b2abdd19d7bcaafaacfde53de.tar.gz linux-ce31847f109c3a5b2abdd19d7bcaafaacfde53de.tar.bz2 linux-ce31847f109c3a5b2abdd19d7bcaafaacfde53de.zip | |
ACPI: battery: Fix possible crash when unregistering a battery hook
[ 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: fa93854f7a7e ("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>
Diffstat (limited to 'drivers/acpi')
| -rw-r--r-- | drivers/acpi/battery.c | 12 |
1 files changed, 9 insertions, 3 deletions
diff --git a/drivers/acpi/battery.c b/drivers/acpi/battery.c index a14852b612bb..e3cbaf3c3bbc 100644 --- a/drivers/acpi/battery.c +++ b/drivers/acpi/battery.c @@ -715,7 +715,7 @@ static void battery_hook_unregister_unlocked(struct acpi_battery_hook *hook) if (!hook->remove_battery(battery->bat, hook)) power_supply_changed(battery->bat); } - list_del(&hook->list); + list_del_init(&hook->list); pr_info("extension unregistered: %s\n", hook->name); } @@ -723,7 +723,14 @@ static void battery_hook_unregister_unlocked(struct acpi_battery_hook *hook) void battery_hook_unregister(struct acpi_battery_hook *hook) { 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); } EXPORT_SYMBOL_GPL(battery_hook_unregister); @@ -733,7 +740,6 @@ void battery_hook_register(struct acpi_battery_hook *hook) struct acpi_battery *battery; mutex_lock(&hook_mutex); - INIT_LIST_HEAD(&hook->list); list_add(&hook->list, &battery_hook_list); /* * Now that the driver is registered, we need |