From: Ard Biesheuvel ardb@kernel.org
commit 4b017e59f01097f19b938f6dc4dc2c4720701610 upstream.
Amadeusz reports KASAN use-after-free errors introduced by commit 3881ee0b1edc ("efi: avoid efivars layer when loading SSDTs from variables"). The problem appears to be that the memory that holds the new ACPI table is now freed unconditionally, instead of only when the ACPI core reported a failure to load the table.
So let's fix this, by omitting the kfree() on success.
Cc: stable@vger.kernel.org # v6.0 Link: https://lore.kernel.org/all/a101a10a-4fbb-5fae-2e3c-76cf96ed8fbd@linux.intel... Fixes: 3881ee0b1edc ("efi: avoid efivars layer when loading SSDTs from variables") Reported-by: Amadeusz Sławiński amadeuszx.slawinski@linux.intel.com Signed-off-by: Ard Biesheuvel ardb@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/firmware/efi/efi.c | 2 ++ 1 file changed, 2 insertions(+)
--- a/drivers/firmware/efi/efi.c +++ b/drivers/firmware/efi/efi.c @@ -269,6 +269,8 @@ static __init int efivar_ssdt_load(void) acpi_status ret = acpi_load_table(data, NULL); if (ret) pr_err("failed to load table: %u\n", ret); + else + continue; } else { pr_err("failed to get var data: 0x%lx\n", status); }