[PATCH 3.18 25/25] fixup: sctp: verify size of a new chunk in _sctp_make_chunk()

[Greg Kroah-Hartman]

3.18-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

Ben writes:
> > +	int chunklen;
> > +
> > +	chunklen = sizeof(*chunk_hdr) + paylen;
> 
> I think this length still needs to be rounded up (with WORD_ROUND here,
> instead of SCTP_PAD4 upstream).

So here's a fix for this problem.


Reported-by: Ben Hutchings <ben.hutchings@xxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 net/sctp/sm_make_chunk.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/net/sctp/sm_make_chunk.c
+++ b/net/sctp/sm_make_chunk.c
@@ -1369,7 +1369,7 @@ static struct sctp_chunk *_sctp_make_chu
 	struct sock *sk;
 	int chunklen;
 
-	chunklen = sizeof(*chunk_hdr) + paylen;
+	chunklen = WORD_ROUND(sizeof(*chunk_hdr) + paylen);
 	if (chunklen > SCTP_MAX_CHUNK_LEN)
 		goto nodata;