kernel.git/net/sctp/ipv6.c, branch linux-5.4.y

sctp: initialize more fields in sctp_v6_from_sk()

2025-09-04T12:05:55Z

[ Upstream commit 2e8750469242cad8f01f320131fd5a6f540dbb99 ] syzbot found that sin6_scope_id was not properly initialized, leading to undefined behavior. Clear sin6_scope_id and sin6_flowinfo. BUG: KMSAN: uninit-value in __sctp_v6_cmp_addr+0x887/0x8c0 net/sctp/ipv6.c:649 __sctp_v6_cmp_addr+0x887/0x8c0 net/sctp/ipv6.c:649 sctp_inet6_cmp_addr+0x4f2/0x510 net/sctp/ipv6.c:983 sctp_bind_addr_conflict+0x22a/0x3b0 net/sctp/bind_addr.c:390 sctp_get_port_local+0x21eb/0x2440 net/sctp/socket.c:8452 sctp_get_port net/sctp/socket.c:8523 [inline] sctp_listen_start net/sctp/socket.c:8567 [inline] sctp_inet_listen+0x710/0xfd0 net/sctp/socket.c:8636 __sys_listen_socket net/socket.c:1912 [inline] __sys_listen net/socket.c:1927 [inline] __do_sys_listen net/socket.c:1932 [inline] __se_sys_listen net/socket.c:1930 [inline] __x64_sys_listen+0x343/0x4c0 net/socket.c:1930 x64_sys_call+0x271d/0x3e20 arch/x86/include/generated/asm/syscalls_64.h:51 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xd9/0x210 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Local variable addr.i.i created at: sctp_get_port net/sctp/socket.c:8515 [inline] sctp_listen_start net/sctp/socket.c:8567 [inline] sctp_inet_listen+0x650/0xfd0 net/sctp/socket.c:8636 __sys_listen_socket net/socket.c:1912 [inline] __sys_listen net/socket.c:1927 [inline] __do_sys_listen net/socket.c:1932 [inline] __se_sys_listen net/socket.c:1930 [inline] __x64_sys_listen+0x343/0x4c0 net/socket.c:1930 Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Reported-by: syzbot+e69f06a0f30116c68056@syzkaller.appspotmail.com Closes: https://lore.kernel.org/netdev/68adc0a2.050a0220.37038e.00c4.GAE@google.com/T/#u Signed-off-by: Eric Dumazet Cc: Marcelo Ricardo Leitner Acked-by: Xin Long Link: https://patch.msgid.link/20250826141314.1802610-1-edumazet@google.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin

sctp: validate from_addr_param return

2021-07-19T06:53:13Z

[ Upstream commit 0c5dc070ff3d6246d22ddd931f23a6266249e3db ] Ilja reported that, simply putting it, nothing was validating that from_addr_param functions were operating on initialized memory. That is, the parameter itself was being validated by sctp_walk_params, but it doesn't check for types and their specific sizes and it could be a 0-length one, causing from_addr_param to potentially work over the next parameter or even uninitialized memory. The fix here is to, in all calls to from_addr_param, check if enough space is there for the wanted IP address type. Reported-by: Ilja Van Sprundel Signed-off-by: Marcelo Ricardo Leitner Signed-off-by: David S. Miller Signed-off-by: Sasha Levin

net-ipv6: bugfix - raw & sctp - switch to ipv6_can_nonlocal_bind()

2021-04-14T06:24:12Z

commit 630e4576f83accf90366686f39808d665d8dbecc upstream. Found by virtue of ipv6 raw sockets not honouring the per-socket IP{,V6}_FREEBIND setting. Based on hits found via: git grep '[.]ip_nonlocal_bind' We fix both raw ipv6 sockets to honour IP{,V6}_FREEBIND and IP{,V6}_TRANSPARENT, and we fix sctp sockets to honour IP{,V6}_TRANSPARENT (they already honoured FREEBIND), and not just the ipv6 'ip_nonlocal_bind' sysctl. The helper is defined as: static inline bool ipv6_can_nonlocal_bind(struct net *net, struct inet_sock *inet) { return net->ipv6.sysctl.ip_nonlocal_bind || inet->freebind || inet->transparent; } so this change only widens the accepted opt-outs and is thus a clean bugfix. I'm not entirely sure what 'fixes' tag to add, since this is AFAICT an ancient bug, but IMHO this should be applied to stable kernels as far back as possible. As such I'm adding a 'fixes' tag with the commit that originally added the helper, which happened in 4.19. Backporting to older LTS kernels (at least 4.9 and 4.14) would presumably require open-coding it or backporting the helper as well. Other possibly relevant commits: v4.18-rc6-1502-g83ba4645152d net: add helpers checking if socket can be bound to nonlocal address v4.18-rc6-1431-gd0c1f01138c4 net/ipv6: allow any source address for sendmsg pktinfo with ip_nonlocal_bind v4.14-rc5-271-gb71d21c274ef sctp: full support for ipv6 ip_nonlocal_bind & IP_FREEBIND v4.7-rc7-1883-g9b9742022888 sctp: support ipv6 nonlocal bind v4.1-12247-g35a256fee52c ipv6: Nonlocal bind Cc: Lorenzo Colitti Fixes: 83ba4645152d ("net: add helpers checking if socket can be bound to nonlocal address") Signed-off-by: Maciej Żenczykowski Reviewed-By: Lorenzo Colitti Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

sctp: fix possibly using a bad saddr with a given dst

2020-06-17T14:40:24Z

[ Upstream commit 582eea230536a6f104097dd46205822005d5fe3a ] Under certain circumstances, depending on the order of addresses on the interfaces, it could be that sctp_v[46]_get_dst() would return a dst with a mismatched struct flowi. For example, if when walking through the bind addresses and the first one is not a match, it saves the dst as a fallback (added in 410f03831c07), but not the flowi. Then if the next one is also not a match, the previous dst will be returned but with the flowi information for the 2nd address, which is wrong. The fix is to use a locally stored flowi that can be used for such attempts, and copy it to the parameter only in case it is a possible match, together with the corresponding dst entry. The patch updates IPv6 code mostly just to be in sync. Even though the issue is also present there, it fallback is not expected to work with IPv6. Fixes: 410f03831c07 ("sctp: add routing output fallback") Reported-by: Jin Meng Signed-off-by: Marcelo Ricardo Leitner Tested-by: Xin Long Signed-off-by: David S. Miller Signed-off-by: Sasha Levin

net: ipv6: add net argument to ip6_dst_lookup_flow

2019-12-18T15:08:40Z

[ Upstream commit c4e85f73afb6384123e5ef1bba3315b2e3ad031e ] This will be used in the conversion of ipv6_stub to ip6_dst_lookup_flow, as some modules currently pass a net argument without a socket to ip6_dst_lookup. This is equivalent to commit 343d60aada5a ("ipv6: change ipv6_stub_impl.ipv6_dst_lookup to take net argument"). Signed-off-by: Sabrina Dubroca Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

ipv6: add priority parameter to ip6_xmit()

2019-09-27T10:05:02Z

Currently, ip6_xmit() sets skb->priority based on sk->sk_priority This is not desirable for TCP since TCP shares the same ctl socket for a given netns. We want to be able to send RST or ACK packets with a non zero skb->priority. This patch has no functional change. Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller

ipv6: elide flowlabel check if no exclusive leases exist

2019-07-09T02:38:03Z

Processes can request ipv6 flowlabels with cmsg IPV6_FLOWINFO. If not set, by default an autogenerated flowlabel is selected. Explicit flowlabels require a control operation per label plus a datapath check on every connection (every datagram if unconnected). This is particularly expensive on unconnected sockets multiplexing many flows, such as QUIC. In the common case, where no lease is exclusive, the check can be safely elided, as both lease request and check trivially succeed. Indeed, autoflowlabel does the same even with exclusive leases. Elide the check if no process has requested an exclusive lease. fl6_sock_lookup previously returns either a reference to a lease or NULL to denote failure. Modify to return a real error and update all callers. On return NULL, they can use the label and will elide the atomic_dec in fl6_sock_release. This is an optimization. Robust applications still have to revert to requesting leases if the fast path fails due to an exclusive lease. Changes RFC->v1: - use static_key_false_deferred to rate limit jump label operations - call static_key_deferred_flush to stop timers on exit - move decrement out of RCU context - defer optimization also if opt data is associated with a lease - updated all fp6_sock_lookup callers, not just udp Signed-off-by: Willem de Bruijn Signed-off-by: David S. Miller

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 104

2019-05-24T15:39:00Z

Based on 1 normalized pattern(s): this sctp implementation is free software you can redistribute it and or modify it under the terms of the gnu general public license as published by the free software foundation either version 2 or at your option any later version this sctp implementation is distributed in the hope that it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details you should have received a copy of the gnu general public license along with gnu cc see the file copying if not see http www gnu org licenses extracted by the scancode license scanner the SPDX license identifier GPL-2.0-or-later has been chosen to replace the boilerplate/reference in 42 file(s). Signed-off-by: Thomas Gleixner Reviewed-by: Kate Stewart Reviewed-by: Richard Fontana Reviewed-by: Allison Randal Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190523091649.683323110@linutronix.de Signed-off-by: Greg Kroah-Hartman

net: rework SIOCGSTAMP ioctl handling

2019-04-19T21:07:40Z

The SIOCGSTAMP/SIOCGSTAMPNS ioctl commands are implemented by many socket protocol handlers, and all of those end up calling the same sock_get_timestamp()/sock_get_timestampns() helper functions, which results in a lot of duplicate code. With the introduction of 64-bit time_t on 32-bit architectures, this gets worse, as we then need four different ioctl commands in each socket protocol implementation. To simplify that, let's add a new .gettstamp() operation in struct proto_ops, and move ioctl implementation into the common sock_ioctl()/compat_sock_ioctl_trans() functions that these all go through. We can reuse the sock_get_timestamp() implementation, but generalize it so it can deal with both native and compat mode, as well as timeval and timespec structures. Acked-by: Stefan Schmidt Acked-by: Neil Horman Acked-by: Marc Kleine-Budde Link: https://lore.kernel.org/lkml/CAK8P3a038aDQQotzua_QtKGhq8O9n+rdiz2=WDCp82ys8eUT+A@mail.gmail.com/ Signed-off-by: Arnd Bergmann Acked-by: Willem de Bruijn Signed-off-by: David S. Miller

sctp: set flow sport from saddr only when it's 0

2019-01-25T02:13:57Z

Now sctp_transport_pmtu() passes transport->saddr into .get_dst() to set flow sport from 'saddr'. However, transport->saddr is set only when transport->dst exists in sctp_transport_route(). If sctp_transport_pmtu() is called without transport->saddr set, like when transport->dst doesn't exists, the flow sport will be set to 0 from transport->saddr, which will cause a wrong route to be got. Commit 6e91b578bf3f ("sctp: re-use sctp_transport_pmtu in sctp_transport_route") made the issue be triggered more easily since sctp_transport_pmtu() would be called in sctp_transport_route() after that. In gerneral, fl4->fl4_sport should always be set to htons(asoc->base.bind_addr.port), unless transport->asoc doesn't exist in sctp_v4/6_get_dst(), which is the case: sctp_ootb_pkt_new() -> sctp_transport_route() For that, we can simply handle it by setting flow sport from saddr only when it's 0 in sctp_v4/6_get_dst(). Fixes: 6e91b578bf3f ("sctp: re-use sctp_transport_pmtu in sctp_transport_route") Reported-by: Ying Xu Signed-off-by: Xin Long Signed-off-by: David S. Miller