Fix sctp privilege elevation (CVE-2006-3745)
sctp_make_abort_user() now takes the msg_len along with the msg
so that we don't have to recalculate the bytes in iovec.
It also uses memcpy_fromiovec() so that we don't go beyond the
length allocated.
It is good to have this fix even if verify_iovec() is fixed to
return error on overflow.
Signed-off-by: Sridhar Samudrala <sri@us.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
diff --git a/net/sctp/sm_statefuns.c b/net/sctp/sm_statefuns.c
index ead3f1b..5b5ae79 100644
--- a/net/sctp/sm_statefuns.c
+++ b/net/sctp/sm_statefuns.c
@@ -4031,18 +4031,12 @@
* from its upper layer, but retransmits data to the far end
* if necessary to fill gaps.
*/
- struct msghdr *msg = arg;
- struct sctp_chunk *abort;
+ struct sctp_chunk *abort = arg;
sctp_disposition_t retval;
retval = SCTP_DISPOSITION_CONSUME;
- /* Generate ABORT chunk to send the peer. */
- abort = sctp_make_abort_user(asoc, NULL, msg);
- if (!abort)
- retval = SCTP_DISPOSITION_NOMEM;
- else
- sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(abort));
+ sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(abort));
/* Even if we can't send the ABORT due to low memory delete the
* TCB. This is a departure from our typical NOMEM handling.
@@ -4166,8 +4160,7 @@
void *arg,
sctp_cmd_seq_t *commands)
{
- struct msghdr *msg = arg;
- struct sctp_chunk *abort;
+ struct sctp_chunk *abort = arg;
sctp_disposition_t retval;
/* Stop T1-init timer */
@@ -4175,12 +4168,7 @@
SCTP_TO(SCTP_EVENT_TIMEOUT_T1_INIT));
retval = SCTP_DISPOSITION_CONSUME;
- /* Generate ABORT chunk to send the peer */
- abort = sctp_make_abort_user(asoc, NULL, msg);
- if (!abort)
- retval = SCTP_DISPOSITION_NOMEM;
- else
- sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(abort));
+ sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(abort));
sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE,
SCTP_STATE(SCTP_STATE_CLOSED));