[Patch v4 03/23] ACPI: Implement proper length checks for mem resources

Jiang Liu
2015-02-05T05:44:29Z

From: Thomas Gleixner <tglx@linutronix.de>

Check whether the resulting length is the same as the given
length. Check for start <= end as well.

We need to hand in the resource for this, so we can apply the flags
directly.

[Jiang] Remove enforcement that resource starting address must be
non-zero.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com>
---
drivers/acpi/resource.c | 62 ++++++++++++++++++++++++++---------------------
1 file changed, 35 insertions(+), 27 deletions(-)

diff --git a/drivers/acpi/resource.c b/drivers/acpi/resource.c
index 1c616a56e007..3e7d9f6eb875 100644
--- a/drivers/acpi/resource.c
+++ b/drivers/acpi/resource.c
@@ -34,21 +34,37 @@
#define valid_IRQ(i) (true)
#endif

-static unsigned long acpi_dev_memresource_flags(u64 len, u8 write_protect,
- bool window)
+static bool acpi_dev_resource_len_valid(u64 start, u64 end, u64 len, bool io)
{
- unsigned long flags = IORESOURCE_MEM;
+ u64 reslen = end - start + 1;

- if (len == 0)
- flags |= IORESOURCE_DISABLED;
+ /*
+ * CHECKME: len might be required to check versus a minimum
+ * length as well. 1 for io is fine, but for memory it does
+ * not make any sense at all.
+ */
+ if (len && reslen && reslen == len && start <= end)
+ return true;
+
+ pr_info("ACPI: invalid or unassigned resource %s [%016llx - %016llx] length [%016llx]\n",
+ io ? "io" : "mem", start, end, len);
+
+ return false;
+}
+
+static void acpi_dev_memresource_flags(struct resource *res, u64 len,
+ u8 write_protect, bool window)
+{
+ res->flags = IORESOURCE_MEM;
+
+ if (!acpi_dev_resource_len_valid(res->start, res->end, len, false))
+ res->flags |= IORESOURCE_DISABLED;

if (write_protect == ACPI_READ_WRITE_MEMORY)
- flags |= IORESOURCE_MEM_WRITEABLE;
+ res->flags |= IORESOURCE_MEM_WRITEABLE;

if (window)
- flags |= IORESOURCE_WINDOW;
-
- return flags;
+ res->flags |= IORESOURCE_WINDOW;
}

static void acpi_dev_get_memresource(struct resource *res, u64 start, u64 len,
@@ -56,7 +72,7 @@ static void acpi_dev_get_memresource(struct resource *res, u64 start, u64 len,
{
res->start = start;
res->end = start + len - 1;
- res->flags = acpi_dev_memresource_flags(len, write_protect, false);
+ acpi_dev_memresource_flags(res, len, write_protect, false);
}

/**
@@ -77,24 +93,18 @@ bool acpi_dev_resource_memory(struct acpi_resource *ares, struct resource *res)
switch (ares->type) {
case ACPI_RESOURCE_TYPE_MEMORY24:
memory24 = &ares->data.memory24;
- if (!memory24->minimum && !memory24->address_length)
- return false;
acpi_dev_get_memresource(res, memory24->minimum,
memory24->address_length,
memory24->write_protect);
break;
case ACPI_RESOURCE_TYPE_MEMORY32:
memory32 = &ares->data.memory32;
- if (!memory32->minimum && !memory32->address_length)
- return false;
acpi_dev_get_memresource(res, memory32->minimum,
memory32->address_length,
memory32->write_protect);
break;
case ACPI_RESOURCE_TYPE_FIXED_MEMORY32:
fixed_memory32 = &ares->data.fixed_memory32;
- if (!fixed_memory32->address && !fixed_memory32->address_length)
- return false;
acpi_dev_get_memresource(res, fixed_memory32->address,
fixed_memory32->address_length,
fixed_memory32->write_protect);
@@ -102,7 +112,8 @@ bool acpi_dev_resource_memory(struct acpi_resource *ares, struct resource *res)
default:
return false;
}
- return true;
+
+ return !(res->flags & IORESOURCE_DISABLED);
}
EXPORT_SYMBOL_GPL(acpi_dev_resource_memory);

@@ -186,7 +197,6 @@ bool acpi_dev_resource_address_space(struct acpi_resource *ares,
acpi_status status;
struct acpi_resource_address64 addr;
bool window;
- u64 len;
u8 io_decode;

status = acpi_resource_to_address64(ares, &addr);
@@ -199,10 +209,9 @@ bool acpi_dev_resource_address_space(struct acpi_resource *ares,

switch(addr.resource_type) {
case ACPI_MEMORY_RANGE:
- len = addr.address.maximum - addr.address.minimum + 1;
- res->flags = acpi_dev_memresource_flags(len,
- addr.info.mem.write_protect,
- window);
+ acpi_dev_memresource_flags(res, addr.address.address_length,
+ addr.info.mem.write_protect,
+ window);
break;
case ACPI_IO_RANGE:
io_decode = addr.address.granularity == 0xfff ?
@@ -236,7 +245,6 @@ bool acpi_dev_resource_ext_address_space(struct acpi_resource *ares,
{
struct acpi_resource_extended_address64 *ext_addr;
bool window;
- u64 len;
u8 io_decode;

if (ares->type != ACPI_RESOURCE_TYPE_EXTENDED_ADDRESS64)
@@ -250,10 +258,10 @@ bool acpi_dev_resource_ext_address_space(struct acpi_resource *ares,

switch(ext_addr->resource_type) {
case ACPI_MEMORY_RANGE:
- len = ext_addr->address.maximum - ext_addr->address.minimum + 1;
- res->flags = acpi_dev_memresource_flags(len,
- ext_addr->info.mem.write_protect,
- window);
+ acpi_dev_memresource_flags(res,
+ ext_addr->address.address_length,
+ ext_addr->info.mem.write_protect,
+ window);
break;
case ACPI_IO_RANGE:
io_decode = ext_addr->address.granularity == 0xfff ?
--
1.7.10.4