linux/net/sctp
Marcelo Ricardo Leitner 458e279f86 sctp: fail if no bound addresses can be used for a given scope
Currently, if you bind the socket to something like:
        servaddr.sin6_family = AF_INET6;
        servaddr.sin6_port = htons(0);
        servaddr.sin6_scope_id = 0;
        inet_pton(AF_INET6, "::1", &servaddr.sin6_addr);

And then request a connect to:
        connaddr.sin6_family = AF_INET6;
        connaddr.sin6_port = htons(20000);
        connaddr.sin6_scope_id = if_nametoindex("lo");
        inet_pton(AF_INET6, "fe88::1", &connaddr.sin6_addr);

What the stack does is:
 - bind the socket
 - create a new asoc
 - to handle the connect
   - copy the addresses that can be used for the given scope
   - try to connect

But the copy returns 0 addresses, and the effect is that it ends up
trying to connect as if the socket wasn't bound, which is not the
desired behavior. This unexpected behavior also allows KASLR leaks
through SCTP diag interface.

The fix here then is, if when trying to copy the addresses that can
be used for the scope used in connect() it returns 0 addresses, bail
out. This is what TCP does with a similar reproducer.

Reported-by: Pietro Borrello <borrello@diag.uniroma1.it>
Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Signed-off-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Reviewed-by: Xin Long <lucien.xin@gmail.com>
Link: https://lore.kernel.org/r/9fcd182f1099f86c6661f3717f63712ddd1c676c.1674496737.git.marcelo.leitner@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-01-24 18:32:33 -08:00
..
associola.c sctp: remove unnecessary NULL check in sctp_association_init() 2022-10-20 21:43:10 -07:00
auth.c sctp: handle the error returned from sctp_auth_asoc_init_active_key 2022-09-30 12:36:40 +01:00
bind_addr.c sctp: fail if no bound addresses can be used for a given scope 2023-01-24 18:32:33 -08:00
chunk.c net: sctp: chunk.c: delete duplicated word 2020-08-24 16:21:43 -07:00
debug.c sctp: add the probe timer in transport for PLPMTUD 2021-06-22 11:28:52 -07:00
diag.c sctp: add dif and sdif check in asoc and ep lookup 2022-11-18 11:42:54 +00:00
endpointola.c sctp: add dif and sdif check in asoc and ep lookup 2022-11-18 11:42:54 +00:00
input.c sctp: add dif and sdif check in asoc and ep lookup 2022-11-18 11:42:54 +00:00
inqueue.c
ipv6.c sctp: add skb_sdif in struct sctp_af 2022-11-18 11:42:54 +00:00
Kconfig sctp: create udp4 sock and add its encap_rcv 2020-10-30 15:23:52 -07:00
Makefile
objcnt.c
offload.c sctp: remove the NETIF_F_SG flag before calling skb_segment 2021-01-16 19:05:59 -08:00
output.c net: allow gso_max_size to exceed 65536 2022-05-16 10:18:55 +01:00
outqueue.c sctp: clear out_curr if all frag chunks of current msg are pruned 2022-11-07 19:59:01 -08:00
primitive.c
proc.c sctp: move hlist_node and hashent out of sctp_ep_common 2021-12-23 11:15:30 +00:00
protocol.c sctp: add dif and sdif check in asoc and ep lookup 2022-11-18 11:42:54 +00:00
sm_make_chunk.c sctp: account stream padding length for reconf chunk 2021-10-14 07:15:22 -07:00
sm_sideeffect.c sctp: check asoc strreset_chunk in sctp_generate_reconf_event 2022-04-23 22:34:17 +01:00
sm_statefuns.c sctp: sm_statefuns: Remove pointer casts of the same type 2022-11-17 13:04:37 +01:00
sm_statetable.c sctp: add the probe timer in transport for PLPMTUD 2021-06-22 11:28:52 -07:00
socket.c Networking changes for 6.2. 2022-12-13 15:47:48 -08:00
stream_interleave.c sctp: remove unnecessary NULL checks in sctp_enqueue_event() 2022-10-20 21:43:10 -07:00
stream_sched_prio.c sctp: delete free member from struct sctp_sched_ops 2022-12-01 20:14:23 -08:00
stream_sched_rr.c sctp: delete free member from struct sctp_sched_ops 2022-12-01 20:14:23 -08:00
stream_sched.c sctp: delete free member from struct sctp_sched_ops 2022-12-01 20:14:23 -08:00
stream.c sctp: fix memory leak in sctp_stream_outq_migrate() 2022-11-29 08:30:50 -08:00
sysctl.c sctp: sysctl: make extra pointers netns aware 2022-12-12 12:57:29 -08:00
transport.c treewide: use get_random_u32_below() instead of deprecated function 2022-11-18 02:15:15 +01:00
tsnmap.c net: sctp: trivial: fix typo in comment 2021-03-04 13:48:32 -08:00
ulpevent.c net: remove noblock parameter from recvmsg() entities 2022-04-12 15:00:25 +02:00
ulpqueue.c sctp: remove unnecessary NULL check in sctp_ulpq_tail_event() 2022-10-20 21:43:10 -07:00