From 4b017e59f01097f19b938f6dc4dc2c4720701610 Mon Sep 17 00:00:00 2001 From: Ard Biesheuvel Date: Fri, 14 Oct 2022 12:25:52 +0200 Subject: efi: ssdt: Don't free memory if ACPI table was loaded successfully MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 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: # v6.0 Link: https://lore.kernel.org/all/a101a10a-4fbb-5fae-2e3c-76cf96ed8fbd@linux.intel.com/ Fixes: 3881ee0b1edc ("efi: avoid efivars layer when loading SSDTs from variables") Reported-by: Amadeusz Sławiński Signed-off-by: Ard Biesheuvel --- drivers/firmware/efi/efi.c | 2 ++ 1 file changed, 2 insertions(+) (limited to 'drivers/firmware') diff --git a/drivers/firmware/efi/efi.c b/drivers/firmware/efi/efi.c index 9624735f1575..3ecdc43a3f2b 100644 --- a/drivers/firmware/efi/efi.c +++ b/drivers/firmware/efi/efi.c @@ -271,6 +271,8 @@ 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); } -- cgit v1.2.3-59-g8ed1b