There is an use-after-free reported by KASAN: BUG: KASAN: use-after-free in acpi_ut_remove_reference+0x3b/0x82 Read of size 1 at addr ffff888112afc460 by task modprobe/2111 CPU: 0 PID: 2111 Comm: modprobe Not tainted 6.1.0-rc7-dirty Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), Call Trace: <TASK> kasan_report+0xae/0xe0 acpi_ut_remove_reference+0x3b/0x82 acpi_ut_copy_iobject_to_iobject+0x3be/0x3d5 acpi_ds_store_object_to_local+0x15d/0x3a0 acpi_ex_store+0x78d/0x7fd acpi_ex_opcode_1A_1T_1R+0xbe4/0xf9b acpi_ps_parse_aml+0x217/0x8d5 ... </TASK> The root cause of the problem is that the acpi_operand_object is freed when acpi_ut_walk_package_tree() fails in acpi_ut_copy_ipackage_to_ipackage(), lead to repeated release in acpi_ut_copy_iobject_to_iobject(). The problem was introduced by "8aa5e56eeb61" commit, this commit is to fix memory leak in acpi_ut_copy_iobject_to_iobject(), repeatedly adding remove operation, lead to "acpi_operand_object" used after free. Fix it by removing acpi_ut_remove_reference() in acpi_ut_copy_ipackage_to_ipackage(). acpi_ut_copy_ipackage_to_ipackage() is called to copy an internal package object into another internal package object, when it fails, the memory of acpi_operand_object should be freed by the caller. Fixes: 8aa5e56eeb61 ("ACPICA: Utilities: Fix memory leak in acpi_ut_copy_iobject_to_iobject") Signed-off-by: Li Zetao <lizetao1@xxxxxxxxxx> --- drivers/acpi/acpica/utcopy.c | 7 ------- 1 file changed, 7 deletions(-) diff --git a/drivers/acpi/acpica/utcopy.c b/drivers/acpi/acpica/utcopy.c index 400b9e15a709..63c17f420fb8 100644 --- a/drivers/acpi/acpica/utcopy.c +++ b/drivers/acpi/acpica/utcopy.c @@ -916,13 +916,6 @@ acpi_ut_copy_ipackage_to_ipackage(union acpi_operand_object *source_obj, status = acpi_ut_walk_package_tree(source_obj, dest_obj, acpi_ut_copy_ielement_to_ielement, walk_state); - if (ACPI_FAILURE(status)) { - - /* On failure, delete the destination package object */ - - acpi_ut_remove_reference(dest_obj); - } - return_ACPI_STATUS(status); } -- 2.31.1