Update Linux to v5.10.109

Sourced from [1]

[1] https://cdn.kernel.org/pub/linux/kernel/v5.x/linux-5.10.109.tar.xz

Change-Id: I19bca9fc6762d4e63bcf3e4cba88bbe560d9c76c
Signed-off-by: Olivier Deprez <olivier.deprez@arm.com>
diff --git a/drivers/misc/mei/interrupt.c b/drivers/misc/mei/interrupt.c
index a70d989..fee6030 100644
--- a/drivers/misc/mei/interrupt.c
+++ b/drivers/misc/mei/interrupt.c
@@ -61,16 +61,21 @@
  *
  * @dev: mei device
  * @hdr: message header
+ * @discard_len: the length of the message to discard (excluding header)
  */
-static void mei_irq_discard_msg(struct mei_device *dev, struct mei_msg_hdr *hdr)
+static void mei_irq_discard_msg(struct mei_device *dev, struct mei_msg_hdr *hdr,
+				size_t discard_len)
 {
-	if (hdr->dma_ring)
-		mei_dma_ring_read(dev, NULL, hdr->extension[0]);
+	if (hdr->dma_ring) {
+		mei_dma_ring_read(dev, NULL,
+				  hdr->extension[dev->rd_msg_hdr_count - 2]);
+		discard_len = 0;
+	}
 	/*
 	 * no need to check for size as it is guarantied
 	 * that length fits into rd_msg_buf
 	 */
-	mei_read_slots(dev, dev->rd_msg_buf, hdr->length);
+	mei_read_slots(dev, dev->rd_msg_buf, discard_len);
 	dev_dbg(dev->dev, "discarding message " MEI_HDR_FMT "\n",
 		MEI_HDR_PRM(hdr));
 }
@@ -80,18 +85,29 @@
  *
  * @cl: reading client
  * @mei_hdr: header of mei client message
+ * @meta: extend meta header
  * @cmpl_list: completion list
  *
  * Return: always 0
  */
 static int mei_cl_irq_read_msg(struct mei_cl *cl,
 			       struct mei_msg_hdr *mei_hdr,
+			       struct mei_ext_meta_hdr *meta,
 			       struct list_head *cmpl_list)
 {
 	struct mei_device *dev = cl->dev;
 	struct mei_cl_cb *cb;
+
 	size_t buf_sz;
 	u32 length;
+	int ext_len;
+
+	length = mei_hdr->length;
+	ext_len = 0;
+	if (mei_hdr->extended) {
+		ext_len = sizeof(*meta) + mei_slots2data(meta->size);
+		length -= ext_len;
+	}
 
 	cb = list_first_entry_or_null(&cl->rd_pending, struct mei_cl_cb, list);
 	if (!cb) {
@@ -105,13 +121,50 @@
 		list_add_tail(&cb->list, &cl->rd_pending);
 	}
 
+	if (mei_hdr->extended) {
+		struct mei_ext_hdr *ext;
+		struct mei_ext_hdr *vtag = NULL;
+
+		ext = mei_ext_begin(meta);
+		do {
+			switch (ext->type) {
+			case MEI_EXT_HDR_VTAG:
+				vtag = ext;
+				break;
+			case MEI_EXT_HDR_NONE:
+				fallthrough;
+			default:
+				cb->status = -EPROTO;
+				break;
+			}
+
+			ext = mei_ext_next(ext);
+		} while (!mei_ext_last(meta, ext));
+
+		if (!vtag) {
+			cl_dbg(dev, cl, "vtag not found in extended header.\n");
+			cb->status = -EPROTO;
+			goto discard;
+		}
+
+		cl_dbg(dev, cl, "vtag: %d\n", vtag->ext_payload[0]);
+		if (cb->vtag && cb->vtag != vtag->ext_payload[0]) {
+			cl_err(dev, cl, "mismatched tag: %d != %d\n",
+			       cb->vtag, vtag->ext_payload[0]);
+			cb->status = -EPROTO;
+			goto discard;
+		}
+		cb->vtag = vtag->ext_payload[0];
+	}
+
 	if (!mei_cl_is_connected(cl)) {
 		cl_dbg(dev, cl, "not connected\n");
 		cb->status = -ENODEV;
 		goto discard;
 	}
 
-	length = mei_hdr->dma_ring ? mei_hdr->extension[0] : mei_hdr->length;
+	if (mei_hdr->dma_ring)
+		length = mei_hdr->extension[mei_data2slots(ext_len)];
 
 	buf_sz = length + cb->buf_idx;
 	/* catch for integer overflow */
@@ -129,11 +182,13 @@
 		goto discard;
 	}
 
-	if (mei_hdr->dma_ring)
+	if (mei_hdr->dma_ring) {
 		mei_dma_ring_read(dev, cb->buf.data + cb->buf_idx, length);
-
-	/*  for DMA read 0 length to generate an interrupt to the device */
-	mei_read_slots(dev, cb->buf.data + cb->buf_idx, mei_hdr->length);
+		/*  for DMA read 0 length to generate interrupt to the device */
+		mei_read_slots(dev, cb->buf.data + cb->buf_idx, 0);
+	} else {
+		mei_read_slots(dev, cb->buf.data + cb->buf_idx, length);
+	}
 
 	cb->buf_idx += length;
 
@@ -150,7 +205,7 @@
 discard:
 	if (cb)
 		list_move_tail(&cb->list, cmpl_list);
-	mei_irq_discard_msg(dev, mei_hdr);
+	mei_irq_discard_msg(dev, mei_hdr, length);
 	return 0;
 }
 
@@ -243,12 +298,17 @@
 static inline int hdr_is_valid(u32 msg_hdr)
 {
 	struct mei_msg_hdr *mei_hdr;
+	u32 expected_len = 0;
 
 	mei_hdr = (struct mei_msg_hdr *)&msg_hdr;
 	if (!msg_hdr || mei_hdr->reserved)
 		return -EBADMSG;
 
-	if (mei_hdr->dma_ring && mei_hdr->length != MEI_SLOT_SIZE)
+	if (mei_hdr->dma_ring)
+		expected_len += MEI_SLOT_SIZE;
+	if (mei_hdr->extended)
+		expected_len += MEI_SLOT_SIZE;
+	if (mei_hdr->length < expected_len)
 		return -EBADMSG;
 
 	return 0;
@@ -268,11 +328,18 @@
 			 struct list_head *cmpl_list, s32 *slots)
 {
 	struct mei_msg_hdr *mei_hdr;
+	struct mei_ext_meta_hdr *meta_hdr = NULL;
 	struct mei_cl *cl;
 	int ret;
+	u32 ext_meta_hdr_u32;
+	u32 hdr_size_left;
+	u32 hdr_size_ext;
+	int i;
+	int ext_hdr_end;
 
 	if (!dev->rd_msg_hdr[0]) {
 		dev->rd_msg_hdr[0] = mei_read_hdr(dev);
+		dev->rd_msg_hdr_count = 1;
 		(*slots)--;
 		dev_dbg(dev->dev, "slots =%08x.\n", *slots);
 
@@ -295,10 +362,54 @@
 		goto end;
 	}
 
+	ext_hdr_end = 1;
+	hdr_size_left = mei_hdr->length;
+
+	if (mei_hdr->extended) {
+		if (!dev->rd_msg_hdr[1]) {
+			ext_meta_hdr_u32 = mei_read_hdr(dev);
+			dev->rd_msg_hdr[1] = ext_meta_hdr_u32;
+			dev->rd_msg_hdr_count++;
+			(*slots)--;
+			dev_dbg(dev->dev, "extended header is %08x\n",
+				ext_meta_hdr_u32);
+		}
+		meta_hdr = ((struct mei_ext_meta_hdr *)dev->rd_msg_hdr + 1);
+		if (check_add_overflow((u32)sizeof(*meta_hdr),
+				       mei_slots2data(meta_hdr->size),
+				       &hdr_size_ext)) {
+			dev_err(dev->dev, "extended message size too big %d\n",
+				meta_hdr->size);
+			return -EBADMSG;
+		}
+		if (hdr_size_left < hdr_size_ext) {
+			dev_err(dev->dev, "corrupted message header len %d\n",
+				mei_hdr->length);
+			return -EBADMSG;
+		}
+		hdr_size_left -= hdr_size_ext;
+
+		ext_hdr_end = meta_hdr->size + 2;
+		for (i = dev->rd_msg_hdr_count; i < ext_hdr_end; i++) {
+			dev->rd_msg_hdr[i] = mei_read_hdr(dev);
+			dev_dbg(dev->dev, "extended header %d is %08x\n", i,
+				dev->rd_msg_hdr[i]);
+			dev->rd_msg_hdr_count++;
+			(*slots)--;
+		}
+	}
+
 	if (mei_hdr->dma_ring) {
-		dev->rd_msg_hdr[1] = mei_read_hdr(dev);
+		if (hdr_size_left != sizeof(dev->rd_msg_hdr[ext_hdr_end])) {
+			dev_err(dev->dev, "corrupted message header len %d\n",
+				mei_hdr->length);
+			return -EBADMSG;
+		}
+
+		dev->rd_msg_hdr[ext_hdr_end] = mei_read_hdr(dev);
+		dev->rd_msg_hdr_count++;
 		(*slots)--;
-		mei_hdr->length = 0;
+		mei_hdr->length -= sizeof(dev->rd_msg_hdr[ext_hdr_end]);
 	}
 
 	/*  HBM message */
@@ -329,7 +440,7 @@
 		 */
 		if (hdr_is_fixed(mei_hdr) ||
 		    dev->dev_state == MEI_DEV_POWER_DOWN) {
-			mei_irq_discard_msg(dev, mei_hdr);
+			mei_irq_discard_msg(dev, mei_hdr, mei_hdr->length);
 			ret = 0;
 			goto reset_slots;
 		}
@@ -339,12 +450,13 @@
 		goto end;
 	}
 
-	ret = mei_cl_irq_read_msg(cl, mei_hdr, cmpl_list);
+	ret = mei_cl_irq_read_msg(cl, mei_hdr, meta_hdr, cmpl_list);
 
 
 reset_slots:
 	/* reset the number of slots and header */
 	memset(dev->rd_msg_hdr, 0, sizeof(dev->rd_msg_hdr));
+	dev->rd_msg_hdr_count = 0;
 	*slots = mei_count_full_read_slots(dev);
 	if (*slots == -EOVERFLOW) {
 		/* overflow - reset */