[SCTP]: Fix sctp_cookie alignment in the packet.
On 64 bit architectures, sctp_cookie sent as part of INIT-ACK is not
aligned on a 64 bit boundry and thus causes unaligned access exceptions.
The layout of the cookie prameter is this:
|<----- Parameter Header --------------------|<--- Cookie DATA --------
-----------------------------------------------------------------------
| param type (16 bits) | param len (16 bits) | sig [32 bytes] | cookie..
-----------------------------------------------------------------------
The cookie data portion contains 64 bit values on 64 bit architechtures
(timeval) that fall on a 32 bit alignment boundry when used as part of
the on-wire format, but align correctly when used in internal
structures. This patch explicitely pads the on-wire format so that
it is properly aligned.
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: Sridhar Samudrala <sri@us.ibm.com>
diff --git a/net/sctp/sm_make_chunk.c b/net/sctp/sm_make_chunk.c
index 556c495..4fe1d6c 100644
--- a/net/sctp/sm_make_chunk.c
+++ b/net/sctp/sm_make_chunk.c
@@ -1275,7 +1275,12 @@
unsigned int keylen;
char *key;
- headersize = sizeof(sctp_paramhdr_t) + SCTP_SECRET_SIZE;
+ /* Header size is static data prior to the actual cookie, including
+ * any padding.
+ */
+ headersize = sizeof(sctp_paramhdr_t) +
+ (sizeof(struct sctp_signed_cookie) -
+ sizeof(struct sctp_cookie));
bodysize = sizeof(struct sctp_cookie)
+ ntohs(init_chunk->chunk_hdr->length) + addrs_len;
@@ -1362,7 +1367,12 @@
struct sk_buff *skb = chunk->skb;
struct timeval tv;
- headersize = sizeof(sctp_chunkhdr_t) + SCTP_SECRET_SIZE;
+ /* Header size is static data prior to the actual cookie, including
+ * any padding.
+ */
+ headersize = sizeof(sctp_chunkhdr_t) +
+ (sizeof(struct sctp_signed_cookie) -
+ sizeof(struct sctp_cookie));
bodysize = ntohs(chunk->chunk_hdr->length) - headersize;
fixed_size = headersize + sizeof(struct sctp_cookie);