kernel/include/net, branch linux-3.17.y

net-timestamp: make tcp_recvmsg call ipv6_recv_error for AF_INET6 socks

2014-12-16T17:37:10Z

[ Upstream commit f4713a3dfad045d46afcb9c2a7d0bba288920ed4 ] TCP timestamping introduced MSG_ERRQUEUE handling for TCP sockets. If the socket is of family AF_INET6, call ipv6_recv_error instead of ip_recv_error. This change is more complex than a single branch due to the loadable ipv6 module. It reuses a pre-existing indirect function call from ping. The ping code is safe to call, because it is part of the core ipv6 module and always present when AF_INET6 sockets are active. Fixes: 4ed2d765 (net-timestamp: TCP timestamping) Signed-off-by: Willem de Bruijn ---- It may also be worthwhile to add WARN_ON_ONCE(sk->family == AF_INET6) to ip_recv_error. Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

net: sctp: fix skb_over_panic when receiving malformed ASCONF chunks

2014-11-21T17:23:16Z

commit 9de7922bc709eee2f609cd01d98aaedc4cf5ea74 upstream. Commit 6f4c618ddb0 ("SCTP : Add paramters validity check for ASCONF chunk") added basic verification of ASCONF chunks, however, it is still possible to remotely crash a server by sending a special crafted ASCONF chunk, even up to pre 2.6.12 kernels: skb_over_panic: text:ffffffffa01ea1c3 len:31056 put:30768 head:ffff88011bd81800 data:ffff88011bd81800 tail:0x7950 end:0x440 dev: ------------[ cut here ]------------ kernel BUG at net/core/skbuff.c:129! [...] Call Trace: [] skb_put+0x5c/0x70 [] sctp_addto_chunk+0x63/0xd0 [sctp] [] sctp_process_asconf+0x1af/0x540 [sctp] [] ? _read_unlock_bh+0x15/0x20 [] sctp_sf_do_asconf+0x168/0x240 [sctp] [] sctp_do_sm+0x71/0x1210 [sctp] [] ? fib_rules_lookup+0xad/0xf0 [] ? sctp_cmp_addr_exact+0x32/0x40 [sctp] [] sctp_assoc_bh_rcv+0xd3/0x180 [sctp] [] sctp_inq_push+0x56/0x80 [sctp] [] sctp_rcv+0x982/0xa10 [sctp] [] ? ipt_local_in_hook+0x23/0x28 [iptable_filter] [] ? nf_iterate+0x69/0xb0 [] ? ip_local_deliver_finish+0x0/0x2d0 [] ? nf_hook_slow+0x76/0x120 [] ? ip_local_deliver_finish+0x0/0x2d0 [] ip_local_deliver_finish+0xdd/0x2d0 [] ip_local_deliver+0x98/0xa0 [] ip_rcv_finish+0x12d/0x440 [] ip_rcv+0x275/0x350 [] __netif_receive_skb+0x4ab/0x750 [] netif_receive_skb+0x58/0x60 This can be triggered e.g., through a simple scripted nmap connection scan injecting the chunk after the handshake, for example, ... -------------- INIT[ASCONF; ASCONF_ACK] -------------> <----------- INIT-ACK[ASCONF; ASCONF_ACK] ------------ -------------------- COOKIE-ECHO --------------------> <-------------------- COOKIE-ACK --------------------- ------------------ ASCONF; UNKNOWN ------------------> ... where ASCONF chunk of length 280 contains 2 parameters ... 1) Add IP address parameter (param length: 16) 2) Add/del IP address parameter (param length: 255) ... followed by an UNKNOWN chunk of e.g. 4 bytes. Here, the Address Parameter in the ASCONF chunk is even missing, too. This is just an example and similarly-crafted ASCONF chunks could be used just as well. The ASCONF chunk passes through sctp_verify_asconf() as all parameters passed sanity checks, and after walking, we ended up successfully at the chunk end boundary, and thus may invoke sctp_process_asconf(). Parameter walking is done with WORD_ROUND() to take padding into account. In sctp_process_asconf()'s TLV processing, we may fail in sctp_process_asconf_param() e.g., due to removal of the IP address that is also the source address of the packet containing the ASCONF chunk, and thus we need to add all TLVs after the failure to our ASCONF response to remote via helper function sctp_add_asconf_response(), which basically invokes a sctp_addto_chunk() adding the error parameters to the given skb. When walking to the next parameter this time, we proceed with ... length = ntohs(asconf_param->param_hdr.length); asconf_param = (void *)asconf_param + length; ... instead of the WORD_ROUND()'ed length, thus resulting here in an off-by-one that leads to reading the follow-up garbage parameter length of 12336, and thus throwing an skb_over_panic for the reply when trying to sctp_addto_chunk() next time, which implicitly calls the skb_put() with that length. Fix it by using sctp_walk_params() [ which is also used in INIT parameter processing ] macro in the verification *and* in ASCONF processing: it will make sure we don't spill over, that we walk parameters WORD_ROUND()'ed. Moreover, we're being more defensive and guard against unknown parameter types and missized addresses. Joint work with Vlad Yasevich. Fixes: b896b82be4ae ("[SCTP] ADDIP: Support for processing incoming ASCONF_ACK chunks.") Signed-off-by: Daniel Borkmann Signed-off-by: Vlad Yasevich Acked-by: Neil Horman Signed-off-by: David S. Miller Cc: Josh Boyer Signed-off-by: Greg Kroah-Hartman

net: sctp: fix panic on duplicate ASCONF chunks

2014-11-21T17:23:16Z

commit b69040d8e39f20d5215a03502a8e8b4c6ab78395 upstream. When receiving a e.g. semi-good formed connection scan in the form of ... -------------- INIT[ASCONF; ASCONF_ACK] -------------> <----------- INIT-ACK[ASCONF; ASCONF_ACK] ------------ -------------------- COOKIE-ECHO --------------------> <-------------------- COOKIE-ACK --------------------- ---------------- ASCONF_a; ASCONF_b -----------------> ... where ASCONF_a equals ASCONF_b chunk (at least both serials need to be equal), we panic an SCTP server! The problem is that good-formed ASCONF chunks that we reply with ASCONF_ACK chunks are cached per serial. Thus, when we receive a same ASCONF chunk twice (e.g. through a lost ASCONF_ACK), we do not need to process them again on the server side (that was the idea, also proposed in the RFC). Instead, we know it was cached and we just resend the cached chunk instead. So far, so good. Where things get nasty is in SCTP's side effect interpreter, that is, sctp_cmd_interpreter(): While incoming ASCONF_a (chunk = event_arg) is being marked !end_of_packet and !singleton, and we have an association context, we do not flush the outqueue the first time after processing the ASCONF_ACK singleton chunk via SCTP_CMD_REPLY. Instead, we keep it queued up, although we set local_cork to 1. Commit 2e3216cd54b1 changed the precedence, so that as long as we get bundled, incoming chunks we try possible bundling on outgoing queue as well. Before this commit, we would just flush the output queue. Now, while ASCONF_a's ASCONF_ACK sits in the corked outq, we continue to process the same ASCONF_b chunk from the packet. As we have cached the previous ASCONF_ACK, we find it, grab it and do another SCTP_CMD_REPLY command on it. So, effectively, we rip the chunk->list pointers and requeue the same ASCONF_ACK chunk another time. Since we process ASCONF_b, it's correctly marked with end_of_packet and we enforce an uncork, and thus flush, thus crashing the kernel. Fix it by testing if the ASCONF_ACK is currently pending and if that is the case, do not requeue it. When flushing the output queue we may relink the chunk for preparing an outgoing packet, but eventually unlink it when it's copied into the skb right before transmission. Joint work with Vlad Yasevich. Fixes: 2e3216cd54b1 ("sctp: Follow security requirement of responding with 1 packet") Signed-off-by: Daniel Borkmann Signed-off-by: Vlad Yasevich Signed-off-by: David S. Miller Cc: Josh Boyer Signed-off-by: Greg Kroah-Hartman

udptunnel: Add SKB_GSO_UDP_TUNNEL during gro_complete.

2014-11-21T17:23:07Z

[ Upstream commit cfdf1e1ba5bf55e095cf4bcaa9585c4759f239e8 ] When doing GRO processing for UDP tunnels, we never add SKB_GSO_UDP_TUNNEL to gso_type - only the type of the inner protocol is added (such as SKB_GSO_TCPV4). The result is that if the packet is later resegmented we will do GSO but not treat it as a tunnel. This results in UDP fragmentation of the outer header instead of (i.e.) TCP segmentation of the inner header as was originally on the wire. Signed-off-by: Jesse Gross Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

drivers/net, ipv6: Select IPv6 fragment idents for virtio UFO packets

2014-11-14T18:10:21Z

[ Upstream commit 5188cd44c55db3e92cd9e77a40b5baa7ed4340f7 ] UFO is now disabled on all drivers that work with virtio net headers, but userland may try to send UFO/IPv6 packets anyway. Instead of sending with ID=0, we should select identifiers on their behalf (as we used to). Signed-off-by: Ben Hutchings Fixes: 916e4cf46d02 ("ipv6: reuse ip6_frag_id from ip6_ufo_append_data") Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

sctp: handle association restarts when the socket is closed.

2014-10-15T10:29:23Z

[ Upstream commit bdf6fa52f01b941d4a80372d56de465bdbbd1d23 ] Currently association restarts do not take into consideration the state of the socket. When a restart happens, the current assocation simply transitions into established state. This creates a condition where a remote system, through a the restart procedure, may create a local association that is no way reachable by user. The conditions to trigger this are as follows: 1) Remote does not acknoledge some data causing data to remain outstanding. 2) Local application calls close() on the socket. Since data is still outstanding, the association is placed in SHUTDOWN_PENDING state. However, the socket is closed. 3) The remote tries to create a new association, triggering a restart on the local system. The association moves from SHUTDOWN_PENDING to ESTABLISHED. At this point, it is no longer reachable by any socket on the local system. This patch addresses the above situation by moving the newly ESTABLISHED association into SHUTDOWN-SENT state and bundling a SHUTDOWN after the COOKIE-ACK chunk. This way, the restarted associate immidiately enters the shutdown procedure and forces the termination of the unreachable association. Reported-by: David Laight Signed-off-by: Vlad Yasevich Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

ipv6: remove rt6i_genid

2014-09-30T18:00:48Z

Eric Dumazet noticed that all no-nonexthop or no-gateway routes which are already marked DST_HOST (e.g. input routes routes) will always be invalidated during sk_dst_check. Thus per-socket dst caching absolutely had no effect and early demuxing had no effect. Thus this patch removes rt6i_genid: fn_sernum already gets modified during add operations, so we only must ensure we mutate fn_sernum during ipv6 address remove operations. This is a fairly cost extensive operations, but address removal should not happen that often. Also our mtu update functions do the same and we heard no complains so far. xfrm policy changes also cause a call into fib6_flush_trees. Also plug a hole in rt6_info (no cacheline changes). I verified via tracing that this change has effect. Cc: Eric Dumazet Cc: YOSHIFUJI Hideaki Cc: Vlad Yasevich Cc: Nicolas Dichtel Cc: Martin Lau Signed-off-by: Hannes Frederic Sowa Signed-off-by: David S. Miller

Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec

2014-09-22T20:41:41Z

Steffen Klassert says: ==================== pull request (net): ipsec 2014-09-22 We generate a blackhole or queueing route if a packet matches an IPsec policy but a state can't be resolved. Here we assume that dst_output() is called to kill these packets. Unfortunately this assumption is not true in all cases, so it is possible that these packets leave the system without the necessary transformations. This pull request contains two patches to fix this issue: 1) Fix for blackhole routed packets. 2) Fix for queue routed packets. Both patches are serious stable candidates. Please pull or let me know if there are problems. ==================== Signed-off-by: David S. Miller

net: sched: shrink struct qdisc_skb_cb to 28 bytes

2014-09-22T18:21:47Z

We cannot make struct qdisc_skb_cb bigger without impacting IPoIB, or increasing skb->cb[] size. Commit e0f31d849867 ("flow_keys: Record IP layer protocol in skb_flow_dissect()") broke IPoIB. Only current offender is sch_choke, and this one do not need an absolutely precise flow key. If we store 17 bytes of flow key, its more than enough. (Its the actual size of flow_keys if it was a packed structure, but we might add new fields at the end of it later) Signed-off-by: Eric Dumazet Fixes: e0f31d849867 ("flow_keys: Record IP layer protocol in skb_flow_dissect()") Signed-off-by: David S. Miller

genetlink: add function genl_has_listeners()

2014-09-19T21:28:26Z

This function is the counterpart of the function netlink_has_listeners(). Signed-off-by: Nicolas Dichtel Acked-by: Pravin B Shelar Signed-off-by: David S. Miller