Commit f6de0a3b authored Apr 24, 2019 by Kamlakant Patel Committed by Greg Kroah-Hartman May 22, 2019

ipmi:ssif: compare block number correctly for multi-part return messages



commit 55be8658c7e2feb11a5b5b33ee031791dbd23a69 upstream.

According to ipmi spec, block number is a number that is incremented,
starting with 0, for each new block of message data returned using the
middle transaction.

Here, the 'blocknum' is data[0] which always starts from zero(0) and
'ssif_info->multi_pos' starts from 1.
So, we need to add +1 to blocknum while comparing with multi_pos.

Fixes: 7d6380cd40f79 ("ipmi:ssif: Fix handling of multi-part return messages").
Reported-by: Kiran Kolukuluru <kirank@ami.com>
Signed-off-by: Kamlakant Patel <kamlakantp@marvell.com>
Message-Id: <1556106615-18722-1-git-send-email-kamlakantp@marvell.com>
[Also added a debug log if the block numbers don't match.]
Signed-off-by: Corey Minyard <cminyard@mvista.com>
Cc: stable@vger.kernel.org # 4.4
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

parent 88681649

drivers/char/ipmi/ipmi_ssif.c

+5 −1

Original line number	Original line	Diff line number	Diff line
	@@ -688,12 +688,16 @@ static void msg_done_handler(struct ssif_info *ssif_info, int result,
	/* End of read */		/* End of read */
	len = ssif_info->multi_len;		len = ssif_info->multi_len;
	data = ssif_info->data;		data = ssif_info->data;
	} else if (blocknum != ssif_info->multi_pos) {		} else if (blocknum + 1 != ssif_info->multi_pos) {
	/*		/*
	* Out of sequence block, just abort. Block		* Out of sequence block, just abort. Block
	* numbers start at zero for the second block,		* numbers start at zero for the second block,
	* but multi_pos starts at one, so the +1.		* but multi_pos starts at one, so the +1.
	*/		*/
			if (ssif_info->ssif_debug & SSIF_DEBUG_MSG)
			dev_dbg(&ssif_info->client->dev,
			"Received message out of sequence, expected %u, got %u\n",
			ssif_info->multi_pos - 1, blocknum);
	result = -EIO;		result = -EIO;
	} else {		} else {
	ssif_inc_stat(ssif_info, received_message_parts);		ssif_inc_stat(ssif_info, received_message_parts);