lkml.org 
[lkml]   [2018]   [Jan]   [29]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH 4.9 19/66] ACPICA: Namespace: fix operand cache leak
Date
4.9-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Seunghun Han <kkamagui@gmail.com>

commit 3b2d69114fefa474fca542e51119036dceb4aa6f upstream.

ACPICA commit a23325b2e583556eae88ed3f764e457786bf4df6

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 gmb_h virtual_box/virtual_box, BIOS
virtual_box 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

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.

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.

Link: https://github.com/acpica/acpica/commit/a23325b2
Signed-off-by: Seunghun Han <kkamagui@gmail.com>
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Lee, Chun-Yi <jlee@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
drivers/acpi/acpica/nsutils.c | 23 +++++++++--------------
1 file changed, 9 insertions(+), 14 deletions(-)

--- a/drivers/acpi/acpica/nsutils.c
+++ b/drivers/acpi/acpica/nsutils.c
@@ -594,25 +594,20 @@ struct acpi_namespace_node *acpi_ns_vali
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

/*
* Free the entire namespace -- all nodes and all objects

\
 
 \ /
  Last update: 2018-01-29 22:16    [W:0.270 / U:2.212 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site