diff options
| author | Andy Shevchenko <andriy.shevchenko@linux.intel.com> | 2023-10-02 16:46:29 +0300 |
|---|---|---|
| committer | Rafael J. Wysocki <rafael.j.wysocki@intel.com> | 2023-10-03 15:57:05 +0200 |
| commit | 046ece773cc77ef5d2a1431b188ac3d0840ed150 (patch) | |
| tree | 16b81a14b8ab374a354ac97f30200cf0d719c5cd /drivers/acpi/property.c | |
| parent | 8a749fd1a8720d4619c91c8b6e7528c0a355c0aa (diff) | |
ACPI: property: Allow _DSD buffer data only for byte accessors
In accordance with ACPI specificication and _DSD data buffer
representation the data there is an array of bytes. Hence,
accessing it with something longer will create a sparse data
which is against of how device property APIs work in general
and also not defined in the ACPI specification (see [1]).
Fix the code to emit an error if non-byte accessor is used to
retrieve _DSD buffer data.
Fixes: 369af6bf2c28 ("ACPI: property: Read buffer properties as integers")
Link: https://uefi.org/specs/ACPI/6.5/19_ASL_Reference.html#buffer-declare-buffer-object # [1]
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
[ rjw: Add missing braces ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Diffstat (limited to 'drivers/acpi/property.c')
| -rw-r--r-- | drivers/acpi/property.c | 19 |
1 files changed, 10 insertions, 9 deletions
diff --git a/drivers/acpi/property.c b/drivers/acpi/property.c index 413e4fcadcaf..99b4e3355435 100644 --- a/drivers/acpi/property.c +++ b/drivers/acpi/property.c @@ -1102,25 +1102,26 @@ static int acpi_data_prop_read(const struct acpi_device_data *data, switch (proptype) { case DEV_PROP_STRING: break; - case DEV_PROP_U8 ... DEV_PROP_U64: + default: if (obj->type == ACPI_TYPE_BUFFER) { if (nval > obj->buffer.length) return -EOVERFLOW; - break; + } else { + if (nval > obj->package.count) + return -EOVERFLOW; } - fallthrough; - default: - if (nval > obj->package.count) - return -EOVERFLOW; break; } if (nval == 0) return -EINVAL; - if (obj->type != ACPI_TYPE_BUFFER) - items = obj->package.elements; - else + if (obj->type == ACPI_TYPE_BUFFER) { + if (proptype != DEV_PROP_U8) + return -EPROTO; items = obj; + } else { + items = obj->package.elements; + } switch (proptype) { case DEV_PROP_U8: |