[PATCH 4.19 081/105] ipmi:ssif: compare block number correctly for multi-part return messages
From: Greg Kroah-Hartman
Date: Mon May 20 2019 - 08:49:35 EST
From: Kamlakant Patel <kamlakantp@xxxxxxxxxxx>
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@xxxxxxx>
Signed-off-by: Kamlakant Patel <kamlakantp@xxxxxxxxxxx>
Message-Id: <1556106615-18722-1-git-send-email-kamlakantp@xxxxxxxxxxx>
[Also added a debug log if the block numbers don't match.]
Signed-off-by: Corey Minyard <cminyard@xxxxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx # 4.4
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/char/ipmi/ipmi_ssif.c | 6 +++++-
1 file changed, 5 insertions(+), 1 deletion(-)
--- a/drivers/char/ipmi/ipmi_ssif.c
+++ b/drivers/char/ipmi/ipmi_ssif.c
@@ -688,12 +688,16 @@ static void msg_done_handler(struct ssif
/* End of read */
len = ssif_info->multi_len;
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
* numbers start at zero for the second block,
* 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;
} else {
ssif_inc_stat(ssif_info, received_message_parts);