2019-04-24 12:01:57

by Kamlakant Patel

[permalink] [raw]
Subject: [PATCH] ipmi:ssif: compare block number correctly for multi-part return messages

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.

This change fixes ("ipmi:ssif: Fix handling of multi-part return
messages").

Reported-by: Kiran Kolukuluru <[email protected]>
Signed-off-by: Kamlakant Patel <[email protected]>
---
drivers/char/ipmi/ipmi_ssif.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/char/ipmi/ipmi_ssif.c b/drivers/char/ipmi/ipmi_ssif.c
index 8b5aec5..2b03845 100644
--- a/drivers/char/ipmi/ipmi_ssif.c
+++ b/drivers/char/ipmi/ipmi_ssif.c
@@ -727,7 +727,7 @@ static void msg_done_handler(struct ssif_info *ssif_info, int result,
/* 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,
--
1.8.3.1


2019-04-24 14:06:43

by Corey Minyard

[permalink] [raw]
Subject: Re: [PATCH] ipmi:ssif: compare block number correctly for multi-part return messages

On Wed, Apr 24, 2019 at 11:50:43AM +0000, Kamlakant Patel wrote:
> 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.

Indeed, I think you are right. I hope there's no other hardware that
mis-interprets this like I did. I'll need to fix my qemu simulation,
too. The funny thing is, the comment is correct. Hmm.

I'll hand-apply this, as it has DOS newlines, too.

-corey

>
> This change fixes ("ipmi:ssif: Fix handling of multi-part return
> messages").
>
> Reported-by: Kiran Kolukuluru <[email protected]>
> Signed-off-by: Kamlakant Patel <[email protected]>
> ---
> drivers/char/ipmi/ipmi_ssif.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/char/ipmi/ipmi_ssif.c b/drivers/char/ipmi/ipmi_ssif.c
> index 8b5aec5..2b03845 100644
> --- a/drivers/char/ipmi/ipmi_ssif.c
> +++ b/drivers/char/ipmi/ipmi_ssif.c
> @@ -727,7 +727,7 @@ static void msg_done_handler(struct ssif_info *ssif_info, int result,
> /* 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,
> --
> 1.8.3.1
>