Hi, Lv Zheng. I added my handcrafted ACPI table under your request, because "acpidump -c on" and "acpidump -c off" doesn't work. 2017-02-21 19:36 GMT+09:00 Seunghun Han <kkamagui@xxxxxxxxx>: > Hello, > > I attached the test results below, > > 2017-02-21 9:53 GMT+09:00 Rowafael J. Wysocki <rjw@xxxxxxxxxxxxx>: >> On Tuesday, February 21, 2017 12:33:08 AM Zheng, Lv wrote: >>> Hi, >>> >>> > From: linux-acpi-owner@xxxxxxxxxxxxxxx [mailto:linux-acpi-owner@xxxxxxxxxxxxxxx] On Behalf Of Seunghun >>> > Han >>> > Subject: [PATCH v2] acpi: acpica: fix acpi operand cache leak >>> > >>> > I'm Seunghun Han, and I work for National Security Research Institute of >>> > South Korea. >>> > >>> > I have been doing a research on ACPI and making a handcrafted ACPI table >>> > for my research. >>> > Errors of handcrafted ACPI tables are handled well in Linux kernel while boot >>> > process, and Linux kernel goes well without critical problems. >>> > But I found some ACPI operand cache leaks in ACPI early abort cases. >>> > >>> > Boot log of ACPI operand cache leak is as follows: >>> > >[ 0.174332] ACPI: Added _OSI(Module Device) >>> > >[ 0.175504] ACPI: Added _OSI(Processor Device) >>> > >[ 0.176010] ACPI: Added _OSI(3.0 _SCP Extensions) >>> > >[ 0.177032] ACPI: Added _OSI(Processor Aggregator Device) >>> > >[ 0.178284] ACPI: SCI (IRQ16705) allocation failed >>> > >[ 0.179352] ACPI Exception: AE_NOT_ACQUIRED, Unable to install System Control Interrupt handler >>> > (20160930/evevent-131) >>> > >[ 0.180008] ACPI: Unable to start the ACPI Interpreter >>> > >[ 0.181125] ACPI Error: Could not remove SCI handler (20160930/evmisc-281) >>> > >[ 0.184068] kmem_cache_destroy Acpi-Operand: Slab cache still has objects >>> > >[ 0.185358] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.10.0-rc3 #2 >>> > >[ 0.186820] Hardware name: innotek GmbH VirtualBox/VirtualBox, BIOS VirtualBox 12/01/2006 >>> > >[ 0.188000] Call Trace: >>> > >[ 0.188000] ? dump_stack+0x5c/0x7d >>> > >[ 0.188000] ? kmem_cache_destroy+0x224/0x230 >>> > >[ 0.188000] ? acpi_sleep_proc_init+0x22/0x22 >>> > >[ 0.188000] ? acpi_os_delete_cache+0xa/0xd >>> > >[ 0.188000] ? acpi_ut_delete_caches+0x3f/0x7b >>> > >[ 0.188000] ? acpi_terminate+0x5/0xf >>> > >[ 0.188000] ? acpi_init+0x288/0x32e >>> > >[ 0.188000] ? __class_create+0x4c/0x80 >>> > >[ 0.188000] ? video_setup+0x7a/0x7a >>> > >[ 0.188000] ? do_one_initcall+0x4e/0x1b0 >>> > >[ 0.188000] ? kernel_init_freeable+0x194/0x21a >>> > >[ 0.188000] ? rest_init+0x80/0x80 >>> > >[ 0.188000] ? kernel_init+0xa/0x100 >>> > >[ 0.188000] ? ret_from_fork+0x25/0x30 >>> >>> I'm more interested in the way of triggering AE_NOT_ACQUIRED error. >>> So could you send us the handcrafted ACPI table or both the "acpidump -c on" and "acpidump -c off" output? I modified FACP, FACS, APIC table in VirtualBox for Linux. Here are raw dumps of table. [ 0.000000] ACPI: FACP 0x00000000DFFF00F0 0000F4 (v04 VBOX VBOXFACP 00000001 ASL 00000061) [ 0.000000] FACP DUMP [ 0.000000] 0x0000: 46 41 43 50 F4 00 00 00 04 60 56 42 4F 58 20 20 [ 0.000000] 0x0010: 56 42 4F 58 46 41 43 50 01 00 00 00 41 53 4C 20 [ 0.000000] 0x0020: 61 00 00 00 00 02 FF DF 80 04 FF DF 41 41 41 41 [ 0.000000] 0x0030: 2E 44 00 00 A1 A0 00 00 00 40 00 00 00 00 00 00 [ 0.000000] 0x0040: 04 40 00 00 00 00 00 00 00 00 00 00 08 40 00 00 [ 0.000000] 0x0050: 20 40 00 00 00 00 00 00 04 02 00 04 02 00 00 00 [ 0.000000] 0x0060: 65 00 E9 03 00 00 00 00 00 00 00 00 00 03 00 00 [ 0.000000] 0x0070: 41 05 00 00 01 08 00 01 50 40 00 00 00 00 00 00 [ 0.000000] 0x0080: 10 00 00 00 00 02 FF DF 00 00 00 00 80 04 FF DF [ 0.000000] 0x0090: 00 00 00 00 01 20 00 02 00 40 00 00 00 00 00 00 [ 0.000000] 0x00A0: 00 00 00 00 00 00 00 00 00 00 00 00 01 10 00 02 [ 0.000000] 0x00B0: 04 40 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 0.000000] 0x00C0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 0.000000] 0x00D0: 01 20 00 03 08 40 00 00 00 00 00 00 01 10 00 01 [ 0.000000] 0x00E0: 20 40 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 0.000000] 0x00F0: 00 00 00 00 [ 0.000000] ACPI: FACS 0x00000000DFFF0200 000040 [ 0.000000] FACS DUMP [ 0.000000] 0x0000: 46 41 43 53 40 00 00 00 00 00 00 00 00 00 00 00 [ 0.000000] 0x0010: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 0.000000] 0x0020: 01 00 00 00 00 00 00 00 00 41 00 00 00 00 00 00 [ 0.000000] 0x0030: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 0.000000] ACPI: FACS 0x00000000DFFF0200 000040 [ 0.000000] FACS DUMP [ 0.000000] 0x0000: 46 41 43 53 40 00 00 00 00 00 00 00 00 00 00 00 [ 0.000000] 0x0010: 00 00 00 00 00 00 00 00 00 41 41 41 41 41 41 41 [ 0.000000] 0x0020: 01 00 00 00 00 00 00 00 00 41 00 00 00 00 00 00 [ 0.000000] 0x0030: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 0.000000] ACPI: APIC 0x00000000DFFF0240 00006C (v02 VBOX VBOXAPIC 00000001 ASL 00000061) [ 0.000000] APIC DUMP [ 0.000000] 0x0000: 41 50 49 43 6C 00 00 00 02 21 56 42 4F 58 20 20 [ 0.000000] 0x0010: 56 42 4F 58 41 50 49 43 01 00 00 00 41 53 4C 20 [ 0.000000] 0x0020: 61 00 00 00 00 00 E0 FE 01 00 00 00 02 0A 00 00 [ 0.000000] 0x0030: 02 00 00 00 00 00 02 0A 00 09 09 00 00 00 0D 00 [ 0.000000] 0x0040: 00 08 00 00 01 00 41 41 41 41 41 41 41 41 41 00 [ 0.000000] 0x0050: 00 08 02 02 01 00 00 00 00 08 03 03 01 00 00 00 [ 0.000000] 0x0060: 01 0C 04 00 00 00 C0 FE 00 00 00 00 If you need additional data, please let me know. Thank you. Best regards. > > Because of the ACPI interpreter error, ACPI function were terminated, > so there is no directory "/proc/acpi". > And when I typed the acpidump command, errors were shown. > > The error are as follows. > root@debian:/proc# acpidump -c on > Cannot open directory - /sys/firmware/acpi/tables > Could not get ACPI tables, AE_NOT_FOUND > > root@debian:/proc# acpidump -c off > Cannot open directory - /sys/firmware/acpi/tables > Could not get ACPI tables, AE_NOT_FOUND > > Could you tell me another way to get information for you? > Thank you. > > Best regards. > >>> > >>> > When early abort is occurred due to invalid ACPI information, Linux kernel >>> > terminates ACPI by calling acpi_terminate() function. >>> > The function calls acpi_ns_terminate() function to delete namespace data >>> > and ACPI operand cache (acpi_gbl_module_code_list). >>> > >>> > But the deletion code in acpi_ns_terminate() function is wrapped in >>> > ACPI_EXEC_APP definition, therefore the code is only executed when the >>> > definition exists. >>> > If the define doesn't exist, ACPI operand cache (acpi_gbl_module_code_list) is >>> > leaked, and stack dump is shown in kernel log. >>> > >>> >>> acpi_ns_terminate() actually shouldn't be invoked by Linux. >>> It's not fully functioning in Linux kernel environment. >>> >>> > This causes a security threat because the old kernel (<= 4.9) shows memory >>> > locations of kernel functions in stack dump, therefore kernel ASLR can be >>> > neutralized. >>> > >>> > To fix ACPI operand leak for enhancing security, I made a patch which removes >>> > the ACPI_EXEC_APP define in acpi_ns_terminate() function for executing the >>> > deletion code unconditionally. >>> >>> However acpi_gbl_module_code_list deletion shouldn't be dependent on ACPI_EXEC_APP. >>> So your change is acceptable. >>> >>> > >>> > I hope that this patch improves the security of Linux kernel. >>> > >>> > Thank you. >>> > >>> > Signed-off-by: Seunghun Han <kkamagui@xxxxxxxxx> >>> > --- >>> > Changes since v1: move position of variables to remove compile warning. >>> > >>> > drivers/acpi/acpica/nsutils.c | 23 +++++++++-------------- >>> > 1 file changed, 9 insertions(+), 14 deletions(-) >>> > >>> > diff --git a/drivers/acpi/acpica/nsutils.c b/drivers/acpi/acpica/nsutils.c >>> > index 691814d..943702d 100644 >>> > --- a/drivers/acpi/acpica/nsutils.c >>> > +++ b/drivers/acpi/acpica/nsutils.c >>> > @@ -594,25 +594,20 @@ struct acpi_namespace_node *acpi_ns_validate_handle(acpi_handle handle) >>> > void acpi_ns_terminate(void) >>> > { >>> > acpi_status status; >>> > + union acpi_operand_object *prev; >>> > + union acpi_operand_object *next; >>> > >>> > ACPI_FUNCTION_TRACE(ns_terminate); >>> > >>> > -#ifdef ACPI_EXEC_APP >>> > - { >>> > - union acpi_operand_object *prev; >>> > - union acpi_operand_object *next; >>> > + /* Delete any module-level code blocks */ >>> > >>> > - /* Delete any module-level code blocks */ >>> > - >>> > - next = acpi_gbl_module_code_list; >>> > - while (next) { >>> > - prev = next; >>> > - next = next->method.mutex; >>> > - prev->method.mutex = NULL; /* Clear the Mutex (cheated) field */ >>> > - acpi_ut_remove_reference(prev); >>> > - } >>> > + next = acpi_gbl_module_code_list; >>> > + while (next) { >>> > + prev = next; >>> > + next = next->method.mutex; >>> > + prev->method.mutex = NULL; /* Clear the Mutex (cheated) field */ >>> > + acpi_ut_remove_reference(prev); >>> > } >>> > -#endif >>> >>> Thus this looks OK to me. >>> >>> > >>> > /* >>> > * Free the entire namespace -- all nodes and all objects >>> > -- >>> > 2.1.4 >> >> I still would prefer it to go in via the upstream. >> >> Thanks, >> Rafael >> -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
