6.12-stable review patch. If anyone has any objections, please let me know.
------------------
From: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
[ Upstream commit ab930483eca9f3e816c35824b5868599af0c61d7 ]
While analysing code for software and OF node for the corner case when
caller asks to read zero items in the supposed to be an array of values
I found that ACPI behaves differently to what OF does, i.e.
1. It returns -EINVAL when caller asks to read zero items from integer
array, while OF returns 0, if no other errors happened.
2. It returns -EINVAL when caller asks to read zero items from string
array, while OF returns -ENODATA, if no other errors happened.
Amend ACPI implementation to follow what OF does.
Fixes: b31384fa5de3 ("Driver core: Unified device properties interface for platform firmware")
Signed-off-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
Link: https://patch.msgid.link/20250203194629.3731895-1-andriy.shevchenko@xxxxxxxxxxxxxxx
[ rjw: Added empty line after a conditional ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/acpi/property.c | 10 +++++-----
1 file changed, 5 insertions(+), 5 deletions(-)
diff --git a/drivers/acpi/property.c b/drivers/acpi/property.c
index 80a52a4e66dd1..e9186339f6e6b 100644
--- a/drivers/acpi/property.c
+++ b/drivers/acpi/property.c
@@ -1187,8 +1187,6 @@ static int acpi_data_prop_read(const struct acpi_device_data *data,
}
break;
}
- if (nval == 0)
- return -EINVAL;
if (obj->type == ACPI_TYPE_BUFFER) {
if (proptype != DEV_PROP_U8)
@@ -1212,9 +1210,11 @@ static int acpi_data_prop_read(const struct acpi_device_data *data,
ret = acpi_copy_property_array_uint(items, (u64 *)val, nval);
break;
case DEV_PROP_STRING:
- ret = acpi_copy_property_array_string(
- items, (char **)val,
- min_t(u32, nval, obj->package.count));
+ nval = min_t(u32, nval, obj->package.count);
+ if (nval == 0)
+ return -ENODATA;
+
+ ret = acpi_copy_property_array_string(items, (char **)val, nval);
break;
default:
ret = -EINVAL;
--
2.39.5
