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author | Seunghun Han <kkamagui@gmail.com> | 2017-04-26 11:18:08 +0300 |
---|---|---|
committer | Rafael J. Wysocki <rafael.j.wysocki@intel.com> | 2017-04-27 01:31:00 +0300 |
commit | 3b2d69114fefa474fca542e51119036dceb4aa6f (patch) | |
tree | eaa7332d633dc3ae738d48f0c8130b83a06eae3d /drivers | |
parent | 2e337c72a3c24f0cf9bf639dc93de0f887d56dba (diff) | |
download | linux-3b2d69114fefa474fca542e51119036dceb4aa6f.tar.xz |
ACPICA: Namespace: fix operand cache leak
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>
Diffstat (limited to 'drivers')
-rw-r--r-- | drivers/acpi/acpica/nsutils.c | 23 |
1 files changed, 9 insertions, 14 deletions
diff --git a/drivers/acpi/acpica/nsutils.c b/drivers/acpi/acpica/nsutils.c index 661676714f7b..b5a291488e3f 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 /* * Free the entire namespace -- all nodes and all objects |