From: Lv Zheng Date: Wed, 30 Apr 2014 10:05:40 +0800 Subject: ACPICA: Tables: Fix invalid pointer accesses in acpi_tb_parse_root_table(). Origin: https://git.kernel.org/cgit/linux/kernel/git/rafael/linux-pm.git/commit?id=d48dc067450d84324067f4472dc0b169e9af4454 Bug-Debian: https://bugs.debian.org/748574 Linux XSDT validation mechanism backport has introduced a regreession: Commit: 671cc68dc61f029d44b43a681356078e02d8dab8 Subject: ACPICA: Back port and refine validation of the XSDT root table. There is a pointer still accessed after unmapping. This patch fixes this issue. Lv Zheng. Fixes: 671cc68dc61f (ACPICA: Back port and refine validation of the XSDT root table.) References: https://bugzilla.kernel.org/show_bug.cgi?id=73911 References: https://bugs.archlinux.org/task/39811 Signed-off-by: Lv Zheng Reported-and-tested-by: Bruce Chiarelli Reported-and-tested-by: Spyros Stathopoulos Signed-off-by: Bob Moore Cc: 3.14+ # 3.14+ Signed-off-by: Rafael J. Wysocki --- drivers/acpi/acpica/tbutils.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) diff --git a/drivers/acpi/acpica/tbutils.c b/drivers/acpi/acpica/tbutils.c index a4702ee..9fb85f3 100644 --- a/drivers/acpi/acpica/tbutils.c +++ b/drivers/acpi/acpica/tbutils.c @@ -461,6 +461,7 @@ acpi_status __init acpi_tb_parse_root_table(acpi_physical_address rsdp_address) u32 table_count; struct acpi_table_header *table; acpi_physical_address address; + acpi_physical_address rsdt_address; u32 length; u8 *table_entry; acpi_status status; @@ -488,11 +489,14 @@ acpi_status __init acpi_tb_parse_root_table(acpi_physical_address rsdp_address) * as per the ACPI specification. */ address = (acpi_physical_address) rsdp->xsdt_physical_address; + rsdt_address = + (acpi_physical_address) rsdp->rsdt_physical_address; table_entry_size = ACPI_XSDT_ENTRY_SIZE; } else { /* Root table is an RSDT (32-bit physical addresses) */ address = (acpi_physical_address) rsdp->rsdt_physical_address; + rsdt_address = address; table_entry_size = ACPI_RSDT_ENTRY_SIZE; } @@ -515,8 +519,7 @@ acpi_status __init acpi_tb_parse_root_table(acpi_physical_address rsdp_address) /* Fall back to the RSDT */ - address = - (acpi_physical_address) rsdp->rsdt_physical_address; + address = rsdt_address; table_entry_size = ACPI_RSDT_ENTRY_SIZE; } }