4.12-stable review patch. If anyone has any objections, please let me know.
------------------
From: Xin Long <lucien.xin@xxxxxxxxx>
[ Upstream commit 10b3bf54406bb7f4e78da9bb2a485c5c986678ad ]
Marcelo noticed an array overflow caused by commit c28445c3cb07
("sctp: add reconf_enable in asoc ep and netns"), in which sctp
would add SCTP_CID_RECONF into extensions when reconf_enable is
set in sctp_make_init and sctp_make_init_ack.
Then now when all ext chunks are set, 4 ext chunk ids can be put
into extensions array while extensions array size is 3. It would
cause a kernel panic because of this overflow.
This patch is to fix it by defining extensions array size is 4 in
both sctp_make_init and sctp_make_init_ack.
Fixes: c28445c3cb07 ("sctp: add reconf_enable in asoc ep and netns")
Signed-off-by: Xin Long <lucien.xin@xxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
net/sctp/sm_make_chunk.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
--- a/net/sctp/sm_make_chunk.c
+++ b/net/sctp/sm_make_chunk.c
@@ -228,7 +228,7 @@ struct sctp_chunk *sctp_make_init(const
sctp_adaptation_ind_param_t aiparam;
sctp_supported_ext_param_t ext_param;
int num_ext = 0;
- __u8 extensions[3];
+ __u8 extensions[4];
sctp_paramhdr_t *auth_chunks = NULL,
*auth_hmacs = NULL;
@@ -396,7 +396,7 @@ struct sctp_chunk *sctp_make_init_ack(co
sctp_adaptation_ind_param_t aiparam;
sctp_supported_ext_param_t ext_param;
int num_ext = 0;
- __u8 extensions[3];
+ __u8 extensions[4];
sctp_paramhdr_t *auth_chunks = NULL,
*auth_hmacs = NULL,
*auth_random = NULL;