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This allows to pull duplicated code out of the switch statement, making it cleaner. Signed-off-by: Dmitry Torokhov Tested-by: Paul E. McKenney --- drivers/hid/hid-core.c | 31 ++++++++++++++----------------- 1 file changed, 14 insertions(+), 17 deletions(-) diff --git a/drivers/hid/hid-core.c b/drivers/hid/hid-core.c index 988d0acbdf04..00942d40fe08 100644 --- a/drivers/hid/hid-core.c +++ b/drivers/hid/hid-core.c @@ -754,35 +754,32 @@ static u8 *fetch_item(__u8 *start, __u8 *end, struct = hid_item *item) } =20 item->format =3D HID_ITEM_FORMAT_SHORT; - item->size =3D b & 3; + item->size =3D BIT(b & 3) >> 1; /* 0, 1, 2, 3 -> 0, 1, 2, 4 */ + + if (end - start < item->size) + return NULL; =20 switch (item->size) { case 0: - return start; + break; =20 case 1: - if ((end - start) < 1) - return NULL; - item->data.u8 =3D *start++; - return start; + item->data.u8 =3D *start; + break; =20 case 2: - if ((end - start) < 2) - return NULL; item->data.u16 =3D get_unaligned_le16(start); - start =3D (__u8 *)((__le16 *)start + 1); - return start; + break; =20 - case 3: - item->size++; - if ((end - start) < 4) - return NULL; + case 4: item->data.u32 =3D get_unaligned_le32(start); - start =3D (__u8 *)((__le32 *)start + 1); - return start; + break; + + default: + unreachable(); } =20 - return NULL; + return start + item->size; } =20 static void hid_scan_input_usage(struct hid_parser *parser, u32 usage) --=20 2.46.1.824.gd892dcdcdd-goog --=20 Dmitry