[PATCH RFC 1/4] HID: treat fixed up report as const

From: Thomas Weißschuh
Date: Tue Jul 30 2024 - 17:37:03 EST


Prepare the HID core for the ->report_fixup() callback to return const
data. This will then allow the HID drivers to store their static reports
in read-only memory.

Signed-off-by: Thomas Weißschuh <linux@xxxxxxxxxxxxxx>
---
drivers/hid/hid-core.c | 7 ++++---
1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/drivers/hid/hid-core.c b/drivers/hid/hid-core.c
index 988d0acbdf04..dc233599ae56 100644
--- a/drivers/hid/hid-core.c
+++ b/drivers/hid/hid-core.c
@@ -1203,6 +1203,7 @@ int hid_open_report(struct hid_device *device)
{
struct hid_parser *parser;
struct hid_item item;
+ const __u8 *fixed_up;
unsigned int size;
__u8 *start;
__u8 *buf;
@@ -1232,11 +1233,11 @@ int hid_open_report(struct hid_device *device)
return -ENOMEM;

if (device->driver->report_fixup)
- start = device->driver->report_fixup(device, buf, &size);
+ fixed_up = device->driver->report_fixup(device, buf, &size);
else
- start = buf;
+ fixed_up = buf;

- start = kmemdup(start, size, GFP_KERNEL);
+ start = kmemdup(fixed_up, size, GFP_KERNEL);
kfree(buf);
if (start == NULL)
return -ENOMEM;

--
2.45.2