diff options
| author | Len Brown <len.brown@intel.com> | 2009-02-04 06:52:12 +0300 |
|---|---|---|
| committer | Len Brown <len.brown@intel.com> | 2009-02-04 06:52:12 +0300 |
| commit | 5ec5d38a1c8af255ffc481c81eef13e9155524b3 (patch) | |
| tree | c87bd7615c56c587c58da20b8bd2775d6010aec1 /drivers/acpi | |
| parent | 3e0676a9b699d12b2bd0a8807459ac4277b181fc (diff) | |
| download | linux-5ec5d38a1c8af255ffc481c81eef13e9155524b3.tar.xz | |
ACPI: make some IO ports off-limits to AML
ACPICA exports acpi_os_validate_address() so the OS
can prevent BIOS AML from accessing specified addresses.
Start using this interface to prevent AML from accessing
some well known IO addresses that the OS "owns".
Signed-off-by: Len Brown <len.brown@intel.com>
Diffstat (limited to 'drivers/acpi')
| -rw-r--r-- | drivers/acpi/osl.c | 50 |
1 files changed, 50 insertions, 0 deletions
diff --git a/drivers/acpi/osl.c b/drivers/acpi/osl.c index 6729a4992f2b..4fb01b0133c7 100644 --- a/drivers/acpi/osl.c +++ b/drivers/acpi/osl.c @@ -1317,6 +1317,54 @@ acpi_os_validate_interface (char *interface) return AE_SUPPORT; } +#ifdef CONFIG_X86 + +struct aml_port_desc { + uint start; + uint end; + char* name; + char warned; +}; + +static struct aml_port_desc aml_invalid_port_list[] = { + {0x20, 0x21, "PIC0", 0}, + {0xA0, 0xA1, "PIC1", 0}, + {0x4D0, 0x4D1, "ELCR", 0} +}; + +/* + * valid_aml_io_address() + * + * if valid, return true + * else invalid, warn once, return false + */ +static bool valid_aml_io_address(uint address, uint length) +{ + int i; + int entries = sizeof(aml_invalid_port_list) / sizeof(struct aml_port_desc); + + for (i = 0; i < entries; ++i) { + if ((address >= aml_invalid_port_list[i].start && + address <= aml_invalid_port_list[i].end) || + (address + length >= aml_invalid_port_list[i].start && + address + length <= aml_invalid_port_list[i].end)) + { + if (!aml_invalid_port_list[i].warned) + { + printk(KERN_ERR "ACPI: Denied BIOS AML access" + " to invalid port 0x%x+0x%x (%s)\n", + address, length, + aml_invalid_port_list[i].name); + aml_invalid_port_list[i].warned = 1; + } + return false; /* invalid */ + } + } + return true; /* valid */ +} +#else +static inline bool valid_aml_io_address(uint address, uint length) { return true; } +#endif /****************************************************************************** * * FUNCTION: acpi_os_validate_address @@ -1346,6 +1394,8 @@ acpi_os_validate_address ( switch (space_id) { case ACPI_ADR_SPACE_SYSTEM_IO: + if (!valid_aml_io_address(address, length)) + return AE_AML_ILLEGAL_ADDRESS; case ACPI_ADR_SPACE_SYSTEM_MEMORY: /* Only interference checks against SystemIO and SytemMemory are needed */ |