diff options
| author | Bob Moore <robert.moore@intel.com> | 2013-05-08 08:01:15 +0400 |
|---|---|---|
| committer | Rafael J. Wysocki <rafael.j.wysocki@intel.com> | 2013-05-08 17:31:37 +0400 |
| commit | 61388f9e5d93053cf399a356414f31f9b4814c6d (patch) | |
| tree | f50814ce10be2256c65aeb83dbd4482733486fff | |
| parent | 371deb9500831ad1afbf9ea00e373f650deaed2f (diff) | |
| download | linux-61388f9e5d93053cf399a356414f31f9b4814c6d.tar.xz | |
ACPICA: Fix possible buffer overflow during a field unit read operation
Can only happen under these conditions: 1) The DSDT version is 1,
meaning integers are 32-bits. 2) The field is between 33 and 64
bits long.
It applies cleanly back to ACPICA 20100806+ (Linux v2.6.37+).
Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Cc: 2.6.37+ <stable@vger.kernel.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
| -rw-r--r-- | drivers/acpi/acpica/exfldio.c | 14 |
1 files changed, 13 insertions, 1 deletions
diff --git a/drivers/acpi/acpica/exfldio.c b/drivers/acpi/acpica/exfldio.c index ec7f5690031b..c84ee956fa4c 100644 --- a/drivers/acpi/acpica/exfldio.c +++ b/drivers/acpi/acpica/exfldio.c @@ -720,7 +720,19 @@ acpi_ex_extract_from_field(union acpi_operand_object *obj_desc, if ((obj_desc->common_field.start_field_bit_offset == 0) && (obj_desc->common_field.bit_length == access_bit_width)) { - status = acpi_ex_field_datum_io(obj_desc, 0, buffer, ACPI_READ); + if (buffer_length >= sizeof(u64)) { + status = + acpi_ex_field_datum_io(obj_desc, 0, buffer, + ACPI_READ); + } else { + /* Use raw_datum (u64) to handle buffers < 64 bits */ + + status = + acpi_ex_field_datum_io(obj_desc, 0, &raw_datum, + ACPI_READ); + ACPI_MEMCPY(buffer, &raw_datum, buffer_length); + } + return_ACPI_STATUS(status); } |