2019-02-03 19:28:30

by Xin Long

[permalink] [raw]
Subject: [PATCHv3 net] sctp: check and update stream->out_curr when allocating stream_out

Now when using stream reconfig to add out streams, stream->out
will get re-allocated, and all old streams' information will
be copied to the new ones and the old ones will be freed.

So without stream->out_curr updated, next time when trying to
send from stream->out_curr stream, a panic would be caused.

This patch is to check and update stream->out_curr when
allocating stream_out.

v1->v2:
- define fa_index() to get elem index from stream->out_curr.
v2->v3:
- repost with no change.

Fixes: 5bbbbe32a431 ("sctp: introduce stream scheduler foundations")
Reported-by: Ying Xu <[email protected]>
Reported-by: [email protected]
Signed-off-by: Xin Long <[email protected]>
---
net/sctp/stream.c | 20 ++++++++++++++++++++
1 file changed, 20 insertions(+)

diff --git a/net/sctp/stream.c b/net/sctp/stream.c
index 80e0ae5..f246331 100644
--- a/net/sctp/stream.c
+++ b/net/sctp/stream.c
@@ -84,6 +84,19 @@ static void fa_zero(struct flex_array *fa, size_t index, size_t count)
}
}

+static size_t fa_index(struct flex_array *fa, void *elem, size_t count)
+{
+ size_t index = 0;
+
+ while (count--) {
+ if (elem == flex_array_get(fa, index))
+ break;
+ index++;
+ }
+
+ return index;
+}
+
/* Migrates chunks from stream queues to new stream queues if needed,
* but not across associations. Also, removes those chunks to streams
* higher than the new max.
@@ -147,6 +160,13 @@ static int sctp_stream_alloc_out(struct sctp_stream *stream, __u16 outcnt,

if (stream->out) {
fa_copy(out, stream->out, 0, min(outcnt, stream->outcnt));
+ if (stream->out_curr) {
+ size_t index = fa_index(stream->out, stream->out_curr,
+ stream->outcnt);
+
+ BUG_ON(index == stream->outcnt);
+ stream->out_curr = flex_array_get(out, index);
+ }
fa_free(stream->out);
}

--
2.1.0



2019-02-03 22:28:12

by Neil Horman

[permalink] [raw]
Subject: Re: [PATCHv3 net] sctp: check and update stream->out_curr when allocating stream_out

On Mon, Feb 04, 2019 at 03:27:58AM +0800, Xin Long wrote:
> Now when using stream reconfig to add out streams, stream->out
> will get re-allocated, and all old streams' information will
> be copied to the new ones and the old ones will be freed.
>
> So without stream->out_curr updated, next time when trying to
> send from stream->out_curr stream, a panic would be caused.
>
> This patch is to check and update stream->out_curr when
> allocating stream_out.
>
> v1->v2:
> - define fa_index() to get elem index from stream->out_curr.
> v2->v3:
> - repost with no change.
>
> Fixes: 5bbbbe32a431 ("sctp: introduce stream scheduler foundations")
> Reported-by: Ying Xu <[email protected]>
> Reported-by: [email protected]
> Signed-off-by: Xin Long <[email protected]>
> ---
> net/sctp/stream.c | 20 ++++++++++++++++++++
> 1 file changed, 20 insertions(+)
>
> diff --git a/net/sctp/stream.c b/net/sctp/stream.c
> index 80e0ae5..f246331 100644
> --- a/net/sctp/stream.c
> +++ b/net/sctp/stream.c
> @@ -84,6 +84,19 @@ static void fa_zero(struct flex_array *fa, size_t index, size_t count)
> }
> }
>
> +static size_t fa_index(struct flex_array *fa, void *elem, size_t count)
> +{
> + size_t index = 0;
> +
> + while (count--) {
> + if (elem == flex_array_get(fa, index))
> + break;
> + index++;
> + }
> +
> + return index;
> +}
> +
> /* Migrates chunks from stream queues to new stream queues if needed,
> * but not across associations. Also, removes those chunks to streams
> * higher than the new max.
> @@ -147,6 +160,13 @@ static int sctp_stream_alloc_out(struct sctp_stream *stream, __u16 outcnt,
>
> if (stream->out) {
> fa_copy(out, stream->out, 0, min(outcnt, stream->outcnt));
> + if (stream->out_curr) {
> + size_t index = fa_index(stream->out, stream->out_curr,
> + stream->outcnt);
> +
> + BUG_ON(index == stream->outcnt);
> + stream->out_curr = flex_array_get(out, index);
> + }
> fa_free(stream->out);
> }
>
> --
> 2.1.0
>
>
Acked-by: Neil Horman <[email protected]>


2019-02-03 22:32:02

by David Miller

[permalink] [raw]
Subject: Re: [PATCHv3 net] sctp: check and update stream->out_curr when allocating stream_out

From: Xin Long <[email protected]>
Date: Mon, 4 Feb 2019 03:27:58 +0800

> Now when using stream reconfig to add out streams, stream->out
> will get re-allocated, and all old streams' information will
> be copied to the new ones and the old ones will be freed.
>
> So without stream->out_curr updated, next time when trying to
> send from stream->out_curr stream, a panic would be caused.
>
> This patch is to check and update stream->out_curr when
> allocating stream_out.
>
> v1->v2:
> - define fa_index() to get elem index from stream->out_curr.
> v2->v3:
> - repost with no change.
>
> Fixes: 5bbbbe32a431 ("sctp: introduce stream scheduler foundations")
> Reported-by: Ying Xu <[email protected]>
> Reported-by: [email protected]
> Signed-off-by: Xin Long <[email protected]>

Applied and queued up for -stable.

Thanks!