HID: bpf: make part of struct hid_device writable

It is useful to change the name, the phys and/or the uniq of a
struct hid_device during .rdesc_fixup().

For example, hid-uclogic.ko changes the uniq to store the firmware version
to differentiate between 2 devices sharing the same PID. In the same
way, changing the device name is useful when the device export 3 nodes,
all with the same name.

Link: https://lore.kernel.org/r/20240608-hid_bpf_struct_ops-v3-16-6ac6ade58329@kernel.org
Signed-off-by: Benjamin Tissoires <bentiss@kernel.org>
This commit is contained in:
Benjamin Tissoires 2024-06-08 11:01:28 +02:00
parent f1a5fb6c7c
commit 33c0fb85b5
2 changed files with 4 additions and 1 deletions

View File

@ -74,6 +74,9 @@ static int hid_bpf_ops_btf_struct_access(struct bpf_verifier_log *log,
const struct hid_bpf_offset_write_range write_ranges[] = {
WRITE_RANGE(hid_bpf_ctx, retval, false),
WRITE_RANGE(hid_device, name, true),
WRITE_RANGE(hid_device, uniq, true),
WRITE_RANGE(hid_device, phys, true),
};
#undef WRITE_RANGE
const struct btf_type *state = NULL;

View File

@ -43,7 +43,7 @@ struct hid_device;
* ``hid`` and ``allocated_size`` are read-only, ``size`` and ``retval`` are read-write.
*/
struct hid_bpf_ctx {
const struct hid_device *hid;
struct hid_device *hid;
__u32 allocated_size;
union {
__s32 retval;