kernel/include/net/sctp/structs.h, branch linux-5.11.y

sctp: bring inet(6)_skb_parm back to sctp_input_cb

2020-11-05T22:27:30Z

inet(6)_skb_parm was removed from sctp_input_cb by Commit a1dd2cf2f1ae ("sctp: allow changing transport encap_port by peer packets"), as it thought sctp_input_cb->header is not used any more in SCTP. syzbot reported a crash: [ ] BUG: KASAN: use-after-free in decode_session6+0xe7c/0x1580 [ ] [ ] Call Trace: [ ] [ ] dump_stack+0x107/0x163 [ ] kasan_report.cold+0x1f/0x37 [ ] decode_session6+0xe7c/0x1580 [ ] __xfrm_policy_check+0x2fa/0x2850 [ ] sctp_rcv+0x12b0/0x2e30 [ ] sctp6_rcv+0x22/0x40 [ ] ip6_protocol_deliver_rcu+0x2e8/0x1680 [ ] ip6_input_finish+0x7f/0x160 [ ] ip6_input+0x9c/0xd0 [ ] ipv6_rcv+0x28e/0x3c0 It was caused by sctp_input_cb->header/IP6CB(skb) still used in sctp rx path decode_session6() but some members overwritten by sctp6_rcv(). This patch is to fix it by bring inet(6)_skb_parm back to sctp_input_cb and not overwriting it in sctp4/6_rcv() and sctp_udp_rcv(). Reported-by: syzbot+5be8aebb1b7dfa90ef31@syzkaller.appspotmail.com Fixes: a1dd2cf2f1ae ("sctp: allow changing transport encap_port by peer packets") Signed-off-by: Xin Long Acked-by: Marcelo Ricardo Leitner Link: https://lore.kernel.org/r/136c1a7a419341487c504be6d1996928d9d16e02.1604472932.git.lucien.xin@gmail.com Signed-off-by: Jakub Kicinski

sctp: add udphdr to overhead when udp_port is set

2020-10-30T22:24:21Z

sctp_mtu_payload() is for calculating the frag size before making chunks from a msg. So we should only add udphdr size to overhead when udp socks are listening, as only then sctp can handle the incoming sctp over udp packets and outgoing sctp over udp packets will be possible. Note that we can't do this according to transport->encap_port, as different transports may be set to different values, while the chunks were made before choosing the transport, we could not be able to meet all rfc6951#section-5.6 recommends. v1->v2: - Add udp_port for sctp_sock to avoid a potential race issue, it will be used in xmit path in the next patch. Signed-off-by: Xin Long Acked-by: Marcelo Ricardo Leitner Signed-off-by: Jakub Kicinski

sctp: allow changing transport encap_port by peer packets

2020-10-30T22:24:16Z

As rfc6951#section-5.4 says: "After finding the SCTP association (which includes checking the verification tag), the UDP source port MUST be stored as the encapsulation port for the destination address the SCTP packet is received from (see Section 5.1). When a non-encapsulated SCTP packet is received by the SCTP stack, the encapsulation of outgoing packets belonging to the same association and the corresponding destination address MUST be disabled." transport encap_port should be updated by a validated incoming packet's udp src port. We save the udp src port in sctp_input_cb->encap_port, and then update the transport in two places: 1. right after vtag is verified, which is required by RFC, and this allows the existent transports to be updated by the chunks that can only be processed on an asoc. 2. right before processing the 'init' where the transports are added, and this allows building a sctp over udp connection by client with the server not knowing the remote encap port. 3. when processing ootb_pkt and creating the temporary transport for the reply pkt. Note that sctp_input_cb->header is removed, as it's not used any more in sctp. v1->v2: - Change encap_port as __be16 for sctp_input_cb. Signed-off-by: Xin Long Acked-by: Marcelo Ricardo Leitner Signed-off-by: Jakub Kicinski

sctp: add encap_port for netns sock asoc and transport

2020-10-30T22:24:06Z

encap_port is added as per netns/sock/assoc/transport, and the latter one's encap_port inherits the former one's by default. The transport's encap_port value would mostly decide if one packet should go out with udp encapsulated or not. This patch also allows users to set netns' encap_port by sysctl. v1->v2: - Change to define encap_port as __be16 for sctp_sock, asoc and transport. v2->v3: - No change. v3->v4: - Add 'encap_port' entry in ip-sysctl.rst. v4->v5: - Improve the description of encap_port in ip-sysctl.rst. Signed-off-by: Xin Long Acked-by: Marcelo Ricardo Leitner Signed-off-by: Jakub Kicinski

net: sctp: Fix IPv6 ancestor_size calc in sctp_copy_descendant

2020-09-20T21:15:12Z

When calculating ancestor_size with IPv6 enabled, simply using sizeof(struct ipv6_pinfo) doesn't account for extra bytes needed for alignment in the struct sctp6_sock. On x86, there aren't any extra bytes, but on ARM the ipv6_pinfo structure is aligned on an 8-byte boundary so there were 4 pad bytes that were omitted from the ancestor_size calculation. This would lead to corruption of the pd_lobby pointers, causing an oops when trying to free the sctp structure on socket close. Fixes: 636d25d557d1 ("sctp: not copy sctp_sock pd_lobby in sctp_copy_descendant") Signed-off-by: Henry Ptasinski Acked-by: Marcelo Ricardo Leitner Signed-off-by: David S. Miller

net: pass a sockptr_t into ->setsockopt

2020-07-24T22:41:54Z

Rework the remaining setsockopt code to pass a sockptr_t instead of a plain user pointer. This removes the last remaining set_fs(KERNEL_DS) outside of architecture specific code. Signed-off-by: Christoph Hellwig Acked-by: Stefan Schmidt [ieee802154] Acked-by: Matthieu Baerts Signed-off-by: David S. Miller

net/ipv6: remove compat_ipv6_{get,set}sockopt

2020-07-20T01:16:41Z

Handle the few cases that need special treatment in-line using in_compat_syscall(). This also removes all the now unused compat_{get,set}sockopt methods. Signed-off-by: Christoph Hellwig Signed-off-by: David S. Miller

net: sctp: drop duplicate words in comments

2020-07-16T03:34:11Z

Drop doubled words in several comments. Signed-off-by: Randy Dunlap Cc: "David S. Miller" Cc: netdev@vger.kernel.org Signed-off-by: Jakub Kicinski

net: sctp: Replace zero-length array with flexible-array member

2020-03-01T05:52:19Z

The current codebase makes use of the zero-length array language extension to the C90 standard, but the preferred mechanism to declare variable-length types such as these ones is a flexible array member[1][2], introduced in C99: struct foo { int stuff; struct boo array[]; }; By making use of the mechanism above, we will get a compiler warning in case the flexible array does not occur last in the structure, which will help us prevent some kind of undefined behavior bugs from being inadvertently introduced[3] to the codebase from now on. Also, notice that, dynamic memory allocations won't be affected by this change: "Flexible array members have incomplete type, and so the sizeof operator may not be applied. As a quirk of the original implementation of zero-length arrays, sizeof evaluates to zero."[1] This issue was found with the help of Coccinelle. [1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html [2] https://github.com/KSPP/linux/issues/21 [3] commit 76497732932f ("cxgb3/l2t: Fix undefined behaviour") Signed-off-by: Gustavo A. R. Silva Signed-off-by: David S. Miller

Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net

2019-11-25T22:57:26Z

Merge in networking bug fixes for merge window. Signed-off-by: David S. Miller