[PATCH net] net: sctp: fix passing wrong parameter header to param_type2af in sctp_process_param

[Daniel Borkmann <dborkman@redhat.com>]

From: Saran Maruti Ramanara <saran.neti@telus.com>

When making use of RFC5061, section 4.2.4. for setting the primary IP
address, we're passing a wrong parameter header to param_type2af(),
resulting always in NULL being returned.

At this point, param.p points to a sctp_addip_param struct, containing
a sctp_paramhdr (type = 0xc004, length = var), and crr_id as a correlation
id. Followed by that, as also presented in RFC5061 section 4.2.4., comes
the actual sctp_addr_param, which also contains a sctp_paramhdr, but
this time with the correct type SCTP_PARAM_IPV{4,6}_ADDRESS that
param_type2af() can make use of. Since we already hold a pointer to
addr_param from previous line, just reuse it for param_type2af().

Fixes: d6de3097592b ("[SCTP]: Add the handling of "Set Primary IP Address" parameter to INIT")
Signed-off-by: Saran Maruti Ramanara <saran.neti@telus.com>
Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
---
 net/sctp/sm_make_chunk.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/sctp/sm_make_chunk.c b/net/sctp/sm_make_chunk.c
index e49e231..06320c8 100644
--- a/net/sctp/sm_make_chunk.c
+++ b/net/sctp/sm_make_chunk.c
@@ -2608,7 +2608,7 @@ do_addr_param:
 
 		addr_param = param.v + sizeof(sctp_addip_param_t);
 
-		af = sctp_get_af_specific(param_type2af(param.p->type));
+		af = sctp_get_af_specific(param_type2af(addr_param->p.type));
 		if (af == NULL)
 			break;
 
-- 
1.7.11.7