HID: fix a couple of off-by-ones

commit 4ab25786 upstream.

There are a few very theoretical off-by-one bugs in report descriptor size
checking when performing a pre-parsing fixup. Fix those.
Reported-by: Ben Hawkes <hawkes@google.com>
Reviewed-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
[bwh: Backported to 3.2: adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

drivers/hid/hid-cherry.c

@@ -29,7 +29,7 @@
 static __u8 *ch_report_fixup(struct hid_device *hdev, __u8 *rdesc,
 		unsigned int *rsize)
 {
-	if (*rsize >= 17 && rdesc[11] == 0x3c && rdesc[12] == 0x02) {
+	if (*rsize >= 18 && rdesc[11] == 0x3c && rdesc[12] == 0x02) {
 		hid_info(hdev, "fixing up Cherry Cymotion report descriptor\n");
 		rdesc[11] = rdesc[16] = 0xff;
 		rdesc[12] = rdesc[17] = 0x03;

drivers/hid/hid-kye.c

@@ -26,7 +26,7 @@
 static __u8 *kye_report_fixup(struct hid_device *hdev, __u8 *rdesc,
 		unsigned int *rsize)
 {
-	if (*rsize >= 74 &&
+	if (*rsize >= 75 &&
 		rdesc[61] == 0x05 && rdesc[62] == 0x08 &&
 		rdesc[63] == 0x19 && rdesc[64] == 0x08 &&
 		rdesc[65] == 0x29 && rdesc[66] == 0x0f &&

drivers/hid/hid-lg.c

@@ -111,14 +111,14 @@ static __u8 *lg_report_fixup(struct hid_device *hdev, __u8 *rdesc,
 {
 	unsigned long quirks = (unsigned long)hid_get_drvdata(hdev);
 
-	if ((quirks & LG_RDESC) && *rsize >= 90 && rdesc[83] == 0x26 &&
+	if ((quirks & LG_RDESC) && *rsize >= 91 && rdesc[83] == 0x26 &&
 			rdesc[84] == 0x8c && rdesc[85] == 0x02) {
 		hid_info(hdev,
 			 "fixing up Logitech keyboard report descriptor\n");
 		rdesc[84] = rdesc[89] = 0x4d;
 		rdesc[85] = rdesc[90] = 0x10;
 	}
-	if ((quirks & LG_RDESC_REL_ABS) && *rsize >= 50 &&
+	if ((quirks & LG_RDESC_REL_ABS) && *rsize >= 51 &&
 			rdesc[32] == 0x81 && rdesc[33] == 0x06 &&
 			rdesc[49] == 0x81 && rdesc[50] == 0x06) {
 		hid_info(hdev,

drivers/hid/hid-monterey.c

@@ -25,7 +25,7 @@
 static __u8 *mr_report_fixup(struct hid_device *hdev, __u8 *rdesc,
 		unsigned int *rsize)
 {
-	if (*rsize >= 30 && rdesc[29] == 0x05 && rdesc[30] == 0x09) {
+	if (*rsize >= 31 && rdesc[29] == 0x05 && rdesc[30] == 0x09) {
 		hid_info(hdev, "fixing up button/consumer in HID report descriptor\n");
 		rdesc[30] = 0x0c;
 	}

drivers/hid/hid-petalynx.c

@@ -26,7 +26,7 @@
 static __u8 *pl_report_fixup(struct hid_device *hdev, __u8 *rdesc,
 		unsigned int *rsize)
 {
-	if (*rsize >= 60 && rdesc[39] == 0x2a && rdesc[40] == 0xf5 &&
+	if (*rsize >= 62 && rdesc[39] == 0x2a && rdesc[40] == 0xf5 &&
 			rdesc[41] == 0x00 && rdesc[59] == 0x26 &&
 			rdesc[60] == 0xf9 && rdesc[61] == 0x00) {
 		hid_info(hdev, "fixing up Petalynx Maxter Remote report descriptor\n");

drivers/hid/hid-sunplus.c

@@ -25,7 +25,7 @@
 static __u8 *sp_report_fixup(struct hid_device *hdev, __u8 *rdesc,
 		unsigned int *rsize)
 {
-	if (*rsize >= 107 && rdesc[104] == 0x26 && rdesc[105] == 0x80 &&
+	if (*rsize >= 112 && rdesc[104] == 0x26 && rdesc[105] == 0x80 &&
 			rdesc[106] == 0x03) {
 		hid_info(hdev, "fixing up Sunplus Wireless Desktop report descriptor\n");
 		rdesc[105] = rdesc[110] = 0x03;