1 files changed, 17 insertions, 8 deletions

diff --git a/drivers/char/ipmi/ipmi_ssif.c b/drivers/char/ipmi/ipmi_ssif.c
index ca9528c4f183..b7a1ae2afaea 100644
--- a/drivers/char/ipmi/ipmi_ssif.c
+++ b/drivers/char/ipmi/ipmi_ssif.c
@@ -632,8 +632,9 @@ static void msg_done_handler(struct ssif_info *ssif_info, int result,
 
 		/* Remove the multi-part read marker. */
 		len -= 2;
+		data += 2;
 		for (i = 0; i < len; i++)
-			ssif_info->data[i] = data[i+2];
+			ssif_info->data[i] = data[i];
 		ssif_info->multi_len = len;
 		ssif_info->multi_pos = 1;
 
@@ -661,8 +662,19 @@ static void msg_done_handler(struct ssif_info *ssif_info, int result,
 		}
 
 		blocknum = data[0];
+		len--;
+		data++;
+
+		if (blocknum != 0xff && len != 31) {
+		    /* All blocks but the last must have 31 data bytes. */
+			result = -EIO;
+			if (ssif_info->ssif_debug & SSIF_DEBUG_MSG)
+				pr_info("Received middle message <31\n");
 
-		if (ssif_info->multi_len + len - 1 > IPMI_MAX_MSG_LENGTH) {
+			goto continue_op;
+		}
+
+		if (ssif_info->multi_len + len > IPMI_MAX_MSG_LENGTH) {
 			/* Received message too big, abort the operation. */
 			result = -E2BIG;
 			if (ssif_info->ssif_debug & SSIF_DEBUG_MSG)
@@ -671,16 +683,14 @@ static void msg_done_handler(struct ssif_info *ssif_info, int result,
 			goto continue_op;
 		}
 
-		/* Remove the blocknum from the data. */
-		len--;
 		for (i = 0; i < len; i++)
-			ssif_info->data[i + ssif_info->multi_len] = data[i + 1];
+			ssif_info->data[i + ssif_info->multi_len] = data[i];
 		ssif_info->multi_len += len;
 		if (blocknum == 0xff) {
 			/* End of read */
 			len = ssif_info->multi_len;
 			data = ssif_info->data;
-		} else if (blocknum + 1 != ssif_info->multi_pos) {
+		} else if (blocknum != ssif_info->multi_pos) {
 			/*
 			 * Out of sequence block, just abort.  Block
 			 * numbers start at zero for the second block,
@@ -707,6 +717,7 @@ static void msg_done_handler(struct ssif_info *ssif_info, int result,
 		}
 	}
 
+ continue_op:
 	if (result < 0) {
 		ssif_inc_stat(ssif_info, receive_errors);
 	} else {
@@ -714,8 +725,6 @@ static void msg_done_handler(struct ssif_info *ssif_info, int result,
 		ssif_inc_stat(ssif_info, received_message_parts);
 	}
 
-
- continue_op:
 	if (ssif_info->ssif_debug & SSIF_DEBUG_STATE)
 		pr_info("DONE 1: state = %d, result=%d\n",
 			ssif_info->ssif_state, result);