On 2022/11/8 1:42, Rafael J. Wysocki wrote:
From: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
A use-after-free in acpi_ps_parse_aml() after a failing invocaion of
acpi_ds_call_control_method() is reported by KASAN [1] and code
inspection reveals that next_walk_state pushed to the thread by
acpi_ds_create_walk_state() is freed on errors, but it is not popped
from the thread beforehand. Thus acpi_ds_get_current_walk_state()
called by acpi_ps_parse_aml() subsequently returns it as the new
walk state which is incorrect.
To address this, make acpi_ds_call_control_method() call
acpi_ds_pop_walk_state() to pop next_walk_state from the thread before
returning an error.
Link: https://lore.kernel.org/linux-acpi/20221019073443.248215-1-chenzhongjin@xxxxxxxxxx/
Reported-by: Chen Zhongjin <chenzhongjin@xxxxxxxxxx>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
---
drivers/acpi/acpica/dsmethod.c | 10 ++++++++--
1 file changed, 8 insertions(+), 2 deletions(-)
Index: linux-pm/drivers/acpi/acpica/dsmethod.c
===================================================================
--- linux-pm.orig/drivers/acpi/acpica/dsmethod.c
+++ linux-pm/drivers/acpi/acpica/dsmethod.c
@@ -517,7 +517,7 @@ acpi_ds_call_control_method(struct acpi_
info = ACPI_ALLOCATE_ZEROED(sizeof(struct acpi_evaluate_info));
if (!info) {
status = AE_NO_MEMORY;
- goto cleanup;
+ goto pop_walk_state;
}
info->parameters = &this_walk_state->operands[0];
@@ -529,7 +529,7 @@ acpi_ds_call_control_method(struct acpi_
ACPI_FREE(info);
if (ACPI_FAILURE(status)) {
- goto cleanup;
+ goto pop_walk_state;
}
next_walk_state->method_nesting_depth =
@@ -575,6 +575,12 @@ acpi_ds_call_control_method(struct acpi_
return_ACPI_STATUS(status);
+pop_walk_state:
+
+ /* On error, pop the walk state to be deleted from thread */
+
+ acpi_ds_pop_walk_state(thread);
+
cleanup:
/* On error, we must terminate the method properly */
LGTM
Reviewed-by: Chen Zhongjin <chenzhongjin@xxxxxxxxxx>
