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2020-01-04sctp: fully initialize v4 addr in some functionsXin Long1-0/+4
[ Upstream commit b6f3320b1d5267e7b583a6d0c88dda518101740c ] Syzbot found a crash: BUG: KMSAN: uninit-value in crc32_body lib/crc32.c:112 [inline] BUG: KMSAN: uninit-value in crc32_le_generic lib/crc32.c:179 [inline] BUG: KMSAN: uninit-value in __crc32c_le_base+0x4fa/0xd30 lib/crc32.c:202 Call Trace: crc32_body lib/crc32.c:112 [inline] crc32_le_generic lib/crc32.c:179 [inline] __crc32c_le_base+0x4fa/0xd30 lib/crc32.c:202 chksum_update+0xb2/0x110 crypto/crc32c_generic.c:90 crypto_shash_update+0x4c5/0x530 crypto/shash.c:107 crc32c+0x150/0x220 lib/libcrc32c.c:47 sctp_csum_update+0x89/0xa0 include/net/sctp/checksum.h:36 __skb_checksum+0x1297/0x12a0 net/core/skbuff.c:2640 sctp_compute_cksum include/net/sctp/checksum.h:59 [inline] sctp_packet_pack net/sctp/output.c:528 [inline] sctp_packet_transmit+0x40fb/0x4250 net/sctp/output.c:597 sctp_outq_flush_transports net/sctp/outqueue.c:1146 [inline] sctp_outq_flush+0x1823/0x5d80 net/sctp/outqueue.c:1194 sctp_outq_uncork+0xd0/0xf0 net/sctp/outqueue.c:757 sctp_cmd_interpreter net/sctp/sm_sideeffect.c:1781 [inline] sctp_side_effects net/sctp/sm_sideeffect.c:1184 [inline] sctp_do_sm+0x8fe1/0x9720 net/sctp/sm_sideeffect.c:1155 sctp_primitive_REQUESTHEARTBEAT+0x175/0x1a0 net/sctp/primitive.c:185 sctp_apply_peer_addr_params+0x212/0x1d40 net/sctp/socket.c:2433 sctp_setsockopt_peer_addr_params net/sctp/socket.c:2686 [inline] sctp_setsockopt+0x189bb/0x19090 net/sctp/socket.c:4672 The issue was caused by transport->ipaddr set with uninit addr param, which was passed by: sctp_transport_init net/sctp/transport.c:47 [inline] sctp_transport_new+0x248/0xa00 net/sctp/transport.c:100 sctp_assoc_add_peer+0x5ba/0x2030 net/sctp/associola.c:611 sctp_process_param net/sctp/sm_make_chunk.c:2524 [inline] where 'addr' is set by sctp_v4_from_addr_param(), and it doesn't initialize the padding of addr->v4. Later when calling sctp_make_heartbeat(), hbinfo.daddr(=transport->ipaddr) will become the part of skb, and the issue occurs. This patch is to fix it by initializing the padding of addr->v4 in sctp_v4_from_addr_param(), as well as other functions that do the similar thing, and these functions shouldn't trust that the caller initializes the memory, as Marcelo suggested. Reported-by: syzbot+6dcbfea81cd3d4dd0b02@syzkaller.appspotmail.com Signed-off-by: Xin Long <lucien.xin@gmail.com> Acked-by: Neil Horman <nhorman@tuxdriver.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-11-10inet: stop leaking jiffies on the wireEric Dumazet1-1/+1
[ Upstream commit a904a0693c189691eeee64f6c6b188bd7dc244e9 ] Historically linux tried to stick to RFC 791, 1122, 2003 for IPv4 ID field generation. RFC 6864 made clear that no matter how hard we try, we can not ensure unicity of IP ID within maximum lifetime for all datagrams with a given source address/destination address/protocol tuple. Linux uses a per socket inet generator (inet_id), initialized at connection startup with a XOR of 'jiffies' and other fields that appear clear on the wire. Thiemo Nagel pointed that this strategy is a privacy concern as this provides 16 bits of entropy to fingerprint devices. Let's switch to a random starting point, this is just as good as far as RFC 6864 is concerned and does not leak anything critical. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Thiemo Nagel <tnagel@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-11-06sctp: not bind the socket in sctp_connectXin Long1-19/+2
commit 9b6c08878e23adb7cc84bdca94d8a944b03f099e upstream. Now when sctp_connect() is called with a wrong sa_family, it binds to a port but doesn't set bp->port, then sctp_get_af_specific will return NULL and sctp_connect() returns -EINVAL. Then if sctp_bind() is called to bind to another port, the last port it has bound will leak due to bp->port is NULL by then. sctp_connect() doesn't need to bind ports, as later __sctp_connect will do it if bp->port is NULL. So remove it from sctp_connect(). While at it, remove the unnecessary sockaddr.sa_family len check as it's already done in sctp_inet_connect. Fixes: 644fbdeacf1d ("sctp: fix the issue that flags are ignored when using kernel_connect") Reported-by: syzbot+079bf326b38072f849d9@syzkaller.appspotmail.com Signed-off-by: Xin Long <lucien.xin@gmail.com> Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-11-06sctp: fix the issue that flags are ignored when using kernel_connectXin Long3-20/+40
commit 644fbdeacf1d3edd366e44b8ba214de9d1dd66a9 upstream. Now sctp uses inet_dgram_connect as its proto_ops .connect, and the flags param can't be passed into its proto .connect where this flags is really needed. sctp works around it by getting flags from socket file in __sctp_connect. It works for connecting from userspace, as inherently the user sock has socket file and it passes f_flags as the flags param into the proto_ops .connect. However, the sock created by sock_create_kern doesn't have a socket file, and it passes the flags (like O_NONBLOCK) by using the flags param in kernel_connect, which calls proto_ops .connect later. So to fix it, this patch defines a new proto_ops .connect for sctp, sctp_inet_connect, which calls __sctp_connect() directly with this flags param. After this, the sctp's proto .connect can be removed. Note that sctp_inet_connect doesn't need to do some checks that are not needed for sctp, which makes thing better than with inet_dgram_connect. Suggested-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Signed-off-by: Xin Long <lucien.xin@gmail.com> Acked-by: Neil Horman <nhorman@tuxdriver.com> Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Reviewed-by: Michal Kubecek <mkubecek@suse.cz> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-10-29sctp: change sctp_prot .no_autobind with trueXin Long1-2/+2
[ Upstream commit 63dfb7938b13fa2c2fbcb45f34d065769eb09414 ] syzbot reported a memory leak: BUG: memory leak, unreferenced object 0xffff888120b3d380 (size 64): backtrace: [...] slab_alloc mm/slab.c:3319 [inline] [...] kmem_cache_alloc+0x13f/0x2c0 mm/slab.c:3483 [...] sctp_bucket_create net/sctp/socket.c:8523 [inline] [...] sctp_get_port_local+0x189/0x5a0 net/sctp/socket.c:8270 [...] sctp_do_bind+0xcc/0x200 net/sctp/socket.c:402 [...] sctp_bindx_add+0x4b/0xd0 net/sctp/socket.c:497 [...] sctp_setsockopt_bindx+0x156/0x1b0 net/sctp/socket.c:1022 [...] sctp_setsockopt net/sctp/socket.c:4641 [inline] [...] sctp_setsockopt+0xaea/0x2dc0 net/sctp/socket.c:4611 [...] sock_common_setsockopt+0x38/0x50 net/core/sock.c:3147 [...] __sys_setsockopt+0x10f/0x220 net/socket.c:2084 [...] __do_sys_setsockopt net/socket.c:2100 [inline] It was caused by when sending msgs without binding a port, in the path: inet_sendmsg() -> inet_send_prepare() -> inet_autobind() -> .get_port/sctp_get_port(), sp->bind_hash will be set while bp->port is not. Later when binding another port by sctp_setsockopt_bindx(), a new bucket will be created as bp->port is not set. sctp's autobind is supposed to call sctp_autobind() where it does all things including setting bp->port. Since sctp_autobind() is called in sctp_sendmsg() if the sk is not yet bound, it should have skipped the auto bind. THis patch is to avoid calling inet_autobind() in inet_send_prepare() by changing sctp_prot .no_autobind with true, also remove the unused .get_port. Reported-by: syzbot+d44f7bbebdea49dbc84a@syzkaller.appspotmail.com Signed-off-by: Xin Long <lucien.xin@gmail.com> Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-09-21sctp: use transport pf_retrans in sctp_do_8_2_transport_strikeXin Long1-1/+1
[ Upstream commit 10eb56c582c557c629271f1ee31e15e7a9b2558b ] Transport should use its own pf_retrans to do the error_count check, instead of asoc's. Otherwise, it's meaningless to make pf_retrans per transport. Fixes: 5aa93bcf66f4 ("sctp: Implement quick failover draft from tsvwg") Signed-off-by: Xin Long <lucien.xin@gmail.com> Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Acked-by: Neil Horman <nhorman@tuxdriver.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-09-21sctp: Fix the link time qualifier of 'sctp_ctrlsock_exit()'Christophe JAILLET1-1/+1
[ Upstream commit b456d72412ca8797234449c25815e82f4e1426c0 ] The '.exit' functions from 'pernet_operations' structure should be marked as __net_exit, not __net_init. Fixes: 8e2d61e0aed2 ("sctp: fix race on protocol/netns initialization") Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr> Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-08-25sctp: fix the transport error_count checkXin Long1-1/+1
[ Upstream commit a1794de8b92ea6bc2037f445b296814ac826693e ] As the annotation says in sctp_do_8_2_transport_strike(): "If the transport error count is greater than the pf_retrans threshold, and less than pathmaxrtx ..." It should be transport->error_count checked with pathmaxrxt, instead of asoc->pf_retrans. Fixes: 5aa93bcf66f4 ("sctp: Implement quick failover draft from tsvwg") Signed-off-by: Xin Long <lucien.xin@gmail.com> Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-07-10sctp: change to hold sk after auth shkey is created successfullyXin Long1-4/+4
[ Upstream commit 25bff6d5478b2a02368097015b7d8eb727c87e16 ] Now in sctp_endpoint_init(), it holds the sk then creates auth shkey. But when the creation fails, it doesn't release the sk, which causes a sk defcnf leak, Here to fix it by only holding the sk when auth shkey is created successfully. Fixes: a29a5bd4f5c3 ("[SCTP]: Implement SCTP-AUTH initializations.") Reported-by: syzbot+afabda3890cc2f765041@syzkaller.appspotmail.com Reported-by: syzbot+276ca1c77a19977c0130@syzkaller.appspotmail.com Signed-off-by: Xin Long <lucien.xin@gmail.com> Acked-by: Neil Horman <nhorman@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-04-27sctp: initialize _pad of sockaddr_in before copying to user memoryXin Long1-0/+1
[ Upstream commit 09279e615c81ce55e04835970601ae286e3facbe ] Syzbot report a kernel-infoleak: BUG: KMSAN: kernel-infoleak in _copy_to_user+0x16b/0x1f0 lib/usercopy.c:32 Call Trace: _copy_to_user+0x16b/0x1f0 lib/usercopy.c:32 copy_to_user include/linux/uaccess.h:174 [inline] sctp_getsockopt_peer_addrs net/sctp/socket.c:5911 [inline] sctp_getsockopt+0x1668e/0x17f70 net/sctp/socket.c:7562 ... Uninit was stored to memory at: sctp_transport_init net/sctp/transport.c:61 [inline] sctp_transport_new+0x16d/0x9a0 net/sctp/transport.c:115 sctp_assoc_add_peer+0x532/0x1f70 net/sctp/associola.c:637 sctp_process_param net/sctp/sm_make_chunk.c:2548 [inline] sctp_process_init+0x1a1b/0x3ed0 net/sctp/sm_make_chunk.c:2361 ... Bytes 8-15 of 16 are uninitialized It was caused by that th _pad field (the 8-15 bytes) of a v4 addr (saved in struct sockaddr_in) wasn't initialized, but directly copied to user memory in sctp_getsockopt_peer_addrs(). So fix it by calling memset(addr->v4.sin_zero, 0, 8) to initialize _pad of sockaddr_in before copying it to user memory in sctp_v4_addr_to_user(), as sctp_v6_addr_to_user() does. Reported-by: syzbot+86b5c7c236a22616a72f@syzkaller.appspotmail.com Signed-off-by: Xin Long <lucien.xin@gmail.com> Tested-by: Alexander Potapenko <glider@google.com> Acked-by: Neil Horman <nhorman@tuxdriver.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-01-26sctp: allocate sctp_sockaddr_entry with kzallocXin Long2-7/+2
commit 400b8b9a2a17918f8ce00786f596f530e7f30d50 upstream. The similar issue as fixed in Commit 4a2eb0c37b47 ("sctp: initialize sin6_flowinfo for ipv6 addrs in sctp_inet6addr_event") also exists in sctp_inetaddr_event, as Alexander noticed. To fix it, allocate sctp_sockaddr_entry with kzalloc for both sctp ipv4 and ipv6 addresses, as does in sctp_v4/6_copy_addrlist(). Reported-by: Alexander Potapenko <glider@google.com> Signed-off-by: Xin Long <lucien.xin@gmail.com> Reported-by: syzbot+ae0c70c0c2d40c51bb92@syzkaller.appspotmail.com Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Acked-by: Neil Horman <nhorman@tuxdriver.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-01-13sctp: initialize sin6_flowinfo for ipv6 addrs in sctp_inet6addr_eventXin Long1-0/+1
[ Upstream commit 4a2eb0c37b4759416996fbb4c45b932500cf06d3 ] syzbot reported a kernel-infoleak, which is caused by an uninitialized field(sin6_flowinfo) of addr->a.v6 in sctp_inet6addr_event(). The call trace is as below: BUG: KMSAN: kernel-infoleak in _copy_to_user+0x19a/0x230 lib/usercopy.c:33 CPU: 1 PID: 8164 Comm: syz-executor2 Not tainted 4.20.0-rc3+ #95 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x32d/0x480 lib/dump_stack.c:113 kmsan_report+0x12c/0x290 mm/kmsan/kmsan.c:683 kmsan_internal_check_memory+0x32a/0xa50 mm/kmsan/kmsan.c:743 kmsan_copy_to_user+0x78/0xd0 mm/kmsan/kmsan_hooks.c:634 _copy_to_user+0x19a/0x230 lib/usercopy.c:33 copy_to_user include/linux/uaccess.h:183 [inline] sctp_getsockopt_local_addrs net/sctp/socket.c:5998 [inline] sctp_getsockopt+0x15248/0x186f0 net/sctp/socket.c:7477 sock_common_getsockopt+0x13f/0x180 net/core/sock.c:2937 __sys_getsockopt+0x489/0x550 net/socket.c:1939 __do_sys_getsockopt net/socket.c:1950 [inline] __se_sys_getsockopt+0xe1/0x100 net/socket.c:1947 __x64_sys_getsockopt+0x62/0x80 net/socket.c:1947 do_syscall_64+0xcf/0x110 arch/x86/entry/common.c:291 entry_SYSCALL_64_after_hwframe+0x63/0xe7 sin6_flowinfo is not really used by SCTP, so it will be fixed by simply setting it to 0. The issue exists since very beginning. Thanks Alexander for the reproducer provided. Reported-by: syzbot+ad5d327e6936a2e284be@syzkaller.appspotmail.com Signed-off-by: Xin Long <lucien.xin@gmail.com> Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Acked-by: Neil Horman <nhorman@tuxdriver.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-12-01sctp: clear the transport of some out_chunk_list chunks in sctp_assoc_rm_peerXin Long1-3/+7
commit df132eff463873e14e019a07f387b4d577d6d1f9 upstream. If a transport is removed by asconf but there still are some chunks with this transport queuing on out_chunk_list, later an use-after-free issue will be caused when accessing this transport from these chunks in sctp_outq_flush(). This is an old bug, we fix it by clearing the transport of these chunks in out_chunk_list when removing a transport in sctp_assoc_rm_peer(). Reported-by: syzbot+56a40ceee5fb35932f4d@syzkaller.appspotmail.com Signed-off-by: Xin Long <lucien.xin@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-11-10sctp: fix race on sctp_id2asocMarcelo Ricardo Leitner1-3/+2
[ Upstream commit b336decab22158937975293aea79396525f92bb3 ] syzbot reported an use-after-free involving sctp_id2asoc. Dmitry Vyukov helped to root cause it and it is because of reading the asoc after it was freed: CPU 1 CPU 2 (working on socket 1) (working on socket 2) sctp_association_destroy sctp_id2asoc spin lock grab the asoc from idr spin unlock spin lock remove asoc from idr spin unlock free(asoc) if asoc->base.sk != sk ... [*] This can only be hit if trying to fetch asocs from different sockets. As we have a single IDR for all asocs, in all SCTP sockets, their id is unique on the system. An application can try to send stuff on an id that matches on another socket, and the if in [*] will protect from such usage. But it didn't consider that as that asoc may belong to another socket, it may be freed in parallel (read: under another socket lock). We fix it by moving the checks in [*] into the protected region. This fixes it because the asoc cannot be freed while the lock is held. Reported-by: syzbot+c7dd55d7aec49d48e49a@syzkaller.appspotmail.com Acked-by: Dmitry Vyukov <dvyukov@google.com> Signed-off-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Acked-by: Neil Horman <nhorman@tuxdriver.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-26sctp: delay the authentication for the duplicated cookie-echo chunkXin Long2-40/+77
[ Upstream commit 59d8d4434f429b4fa8a346fd889058bda427a837 ] Now sctp only delays the authentication for the normal cookie-echo chunk by setting chunk->auth_chunk in sctp_endpoint_bh_rcv(). But for the duplicated one with auth, in sctp_assoc_bh_rcv(), it does authentication first based on the old asoc, which will definitely fail due to the different auth info in the old asoc. The duplicated cookie-echo chunk will create a new asoc with the auth info from this chunk, and the authentication should also be done with the new asoc's auth info for all of the collision 'A', 'B' and 'D'. Otherwise, the duplicated cookie-echo chunk with auth will never pass the authentication and create the new connection. This issue exists since very beginning, and this fix is to make sctp_assoc_bh_rcv() follow the way sctp_endpoint_bh_rcv() does for the normal cookie-echo chunk to delay the authentication. While at it, remove the unused params from sctp_sf_authenticate() and define sctp_auth_chunk_verify() used for all the places that do the delayed authentication. v1->v2: fix the typo in changelog as Marcelo noticed. Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Signed-off-by: Xin Long <lucien.xin@gmail.com> Acked-by: Neil Horman <nhorman@tuxdriver.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-26sctp: fix the issue that the cookie-ack with auth can't get processedXin Long1-1/+1
[ Upstream commit ce402f044e4e432c296f90eaabb8dbe8f3624391 ] When auth is enabled for cookie-ack chunk, in sctp_inq_pop, sctp processes auth chunk first, then continues to the next chunk in this packet if chunk_end + chunk_hdr size < skb_tail_pointer(). Otherwise, it will go to the next packet or discard this chunk. However, it missed the fact that cookie-ack chunk's size is equal to chunk_hdr size, which couldn't match that check, and thus this chunk would not get processed. This patch fixes it by changing the check to chunk_end + chunk_hdr size <= skb_tail_pointer(). Fixes: 26b87c788100 ("net: sctp: fix remote memory pressure from excessive queueing") Signed-off-by: Xin Long <lucien.xin@gmail.com> Acked-by: Neil Horman <nhorman@tuxdriver.com> Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-26sctp: use the old asoc when making the cookie-ack chunk in dupcook_dXin Long1-1/+1
[ Upstream commit 46e16d4b956867013e0bbd7f2bad206f4aa55752 ] When processing a duplicate cookie-echo chunk, for case 'D', sctp will not process the param from this chunk. It means old asoc has nothing to be updated, and the new temp asoc doesn't have the complete info. So there's no reason to use the new asoc when creating the cookie-ack chunk. Otherwise, like when auth is enabled for cookie-ack, the chunk can not be set with auth, and it will definitely be dropped by peer. This issue is there since very beginning, and we fix it by using the old asoc instead. Signed-off-by: Xin Long <lucien.xin@gmail.com> Acked-by: Neil Horman <nhorman@tuxdriver.com> Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-26sctp: handle two v4 addrs comparison in sctp_inet6_cmp_addrXin Long1-0/+3
[ Upstream commit d625329b06e46bd20baf9ee40847d11982569204 ] Since sctp ipv6 socket also supports v4 addrs, it's possible to compare two v4 addrs in pf v6 .cmp_addr, sctp_inet6_cmp_addr. However after Commit 1071ec9d453a ("sctp: do not check port in sctp_inet6_cmp_addr"), it no longer calls af1->cmp_addr, which in this case is sctp_v4_cmp_addr, but calls __sctp_v6_cmp_addr where it handles them as two v6 addrs. It would cause a out of bounds crash. syzbot found this crash when trying to bind two v4 addrs to a v6 socket. This patch fixes it by adding the process for two v4 addrs in sctp_inet6_cmp_addr. Fixes: 1071ec9d453a ("sctp: do not check port in sctp_inet6_cmp_addr") Reported-by: syzbot+cd494c1dd681d4d93ebb@syzkaller.appspotmail.com Signed-off-by: Xin Long <lucien.xin@gmail.com> Acked-by: Neil Horman <nhorman@tuxdriver.com> Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-04-29sctp: do not check port in sctp_inet6_cmp_addrXin Long1-30/+30
[ Upstream commit 1071ec9d453a38023579714b64a951a2fb982071 ] pf->cmp_addr() is called before binding a v6 address to the sock. It should not check ports, like in sctp_inet_cmp_addr. But sctp_inet6_cmp_addr checks the addr by invoking af(6)->cmp_addr, sctp_v6_cmp_addr where it also compares the ports. This would cause that setsockopt(SCTP_SOCKOPT_BINDX_ADD) could bind multiple duplicated IPv6 addresses after Commit 40b4f0fd74e4 ("sctp: lack the check for ports in sctp_v6_cmp_addr"). This patch is to remove af->cmp_addr called in sctp_inet6_cmp_addr, but do the proper check for both v6 addrs and v4mapped addrs. v1->v2: - define __sctp_v6_cmp_addr to do the common address comparison used for both pf and af v6 cmp_addr. Fixes: 40b4f0fd74e4 ("sctp: lack the check for ports in sctp_v6_cmp_addr") Reported-by: Jianwen Ji <jiji@redhat.com> Signed-off-by: Xin Long <lucien.xin@gmail.com> Acked-by: Neil Horman <nhorman@tuxdriver.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-04-13sctp: sctp_sockaddr_af must check minimal addr length for AF_INET6Eric Dumazet1-5/+8
[ Upstream commit 81e98370293afcb58340ce8bd71af7b97f925c26 ] Check must happen before call to ipv6_addr_v4mapped() syzbot report was : BUG: KMSAN: uninit-value in sctp_sockaddr_af net/sctp/socket.c:359 [inline] BUG: KMSAN: uninit-value in sctp_do_bind+0x60f/0xdc0 net/sctp/socket.c:384 CPU: 0 PID: 3576 Comm: syzkaller968804 Not tainted 4.16.0+ #82 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x185/0x1d0 lib/dump_stack.c:53 kmsan_report+0x142/0x240 mm/kmsan/kmsan.c:1067 __msan_warning_32+0x6c/0xb0 mm/kmsan/kmsan_instr.c:676 sctp_sockaddr_af net/sctp/socket.c:359 [inline] sctp_do_bind+0x60f/0xdc0 net/sctp/socket.c:384 sctp_bind+0x149/0x190 net/sctp/socket.c:332 inet6_bind+0x1fd/0x1820 net/ipv6/af_inet6.c:293 SYSC_bind+0x3f2/0x4b0 net/socket.c:1474 SyS_bind+0x54/0x80 net/socket.c:1460 do_syscall_64+0x309/0x430 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x3d/0xa2 RIP: 0033:0x43fd49 RSP: 002b:00007ffe99df3d28 EFLAGS: 00000213 ORIG_RAX: 0000000000000031 RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 000000000043fd49 RDX: 0000000000000010 RSI: 0000000020000000 RDI: 0000000000000003 RBP: 00000000006ca018 R08: 00000000004002c8 R09: 00000000004002c8 R10: 00000000004002c8 R11: 0000000000000213 R12: 0000000000401670 R13: 0000000000401700 R14: 0000000000000000 R15: 0000000000000000 Local variable description: ----address@SYSC_bind Variable was created at: SYSC_bind+0x6f/0x4b0 net/socket.c:1461 SyS_bind+0x54/0x80 net/socket.c:1460 Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Vlad Yasevich <vyasevich@gmail.com> Cc: Neil Horman <nhorman@tuxdriver.com> Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-04-13sctp: do not leak kernel memory to user spaceEric Dumazet1-1/+3
[ Upstream commit 6780db244d6b1537d139dea0ec8aad10cf9e4adb ] syzbot produced a nice report [1] Issue here is that a recvmmsg() managed to leak 8 bytes of kernel memory to user space, because sin_zero (padding field) was not properly cleared. [1] BUG: KMSAN: uninit-value in copy_to_user include/linux/uaccess.h:184 [inline] BUG: KMSAN: uninit-value in move_addr_to_user+0x32e/0x530 net/socket.c:227 CPU: 1 PID: 3586 Comm: syzkaller481044 Not tainted 4.16.0+ #82 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x185/0x1d0 lib/dump_stack.c:53 kmsan_report+0x142/0x240 mm/kmsan/kmsan.c:1067 kmsan_internal_check_memory+0x164/0x1d0 mm/kmsan/kmsan.c:1176 kmsan_copy_to_user+0x69/0x160 mm/kmsan/kmsan.c:1199 copy_to_user include/linux/uaccess.h:184 [inline] move_addr_to_user+0x32e/0x530 net/socket.c:227 ___sys_recvmsg+0x4e2/0x810 net/socket.c:2211 __sys_recvmmsg+0x54e/0xdb0 net/socket.c:2313 SYSC_recvmmsg+0x29b/0x3e0 net/socket.c:2394 SyS_recvmmsg+0x76/0xa0 net/socket.c:2378 do_syscall_64+0x309/0x430 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x3d/0xa2 RIP: 0033:0x4401c9 RSP: 002b:00007ffc56f73098 EFLAGS: 00000217 ORIG_RAX: 000000000000012b RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 00000000004401c9 RDX: 0000000000000001 RSI: 0000000020003ac0 RDI: 0000000000000003 RBP: 00000000006ca018 R08: 0000000020003bc0 R09: 0000000000000010 R10: 0000000000000000 R11: 0000000000000217 R12: 0000000000401af0 R13: 0000000000401b80 R14: 0000000000000000 R15: 0000000000000000 Local variable description: ----addr@___sys_recvmsg Variable was created at: ___sys_recvmsg+0xd5/0x810 net/socket.c:2172 __sys_recvmmsg+0x54e/0xdb0 net/socket.c:2313 Bytes 8-15 of 16 are uninitialized ================================================================== Kernel panic - not syncing: panic_on_warn set ... CPU: 1 PID: 3586 Comm: syzkaller481044 Tainted: G B 4.16.0+ #82 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x185/0x1d0 lib/dump_stack.c:53 panic+0x39d/0x940 kernel/panic.c:183 kmsan_report+0x238/0x240 mm/kmsan/kmsan.c:1083 kmsan_internal_check_memory+0x164/0x1d0 mm/kmsan/kmsan.c:1176 kmsan_copy_to_user+0x69/0x160 mm/kmsan/kmsan.c:1199 copy_to_user include/linux/uaccess.h:184 [inline] move_addr_to_user+0x32e/0x530 net/socket.c:227 ___sys_recvmsg+0x4e2/0x810 net/socket.c:2211 __sys_recvmmsg+0x54e/0xdb0 net/socket.c:2313 SYSC_recvmmsg+0x29b/0x3e0 net/socket.c:2394 SyS_recvmmsg+0x76/0xa0 net/socket.c:2378 do_syscall_64+0x309/0x430 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x3d/0xa2 Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Vlad Yasevich <vyasevich@gmail.com> Cc: Neil Horman <nhorman@tuxdriver.com> Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-04-13sctp: fix recursive locking warning in sctp_do_peeloffXin Long1-2/+2
[ Upstream commit 6dfe4b97e08ec3d1a593fdaca099f0ef0a3a19e6 ] Dmitry got the following recursive locking report while running syzkaller fuzzer, the Call Trace: __dump_stack lib/dump_stack.c:16 [inline] dump_stack+0x2ee/0x3ef lib/dump_stack.c:52 print_deadlock_bug kernel/locking/lockdep.c:1729 [inline] check_deadlock kernel/locking/lockdep.c:1773 [inline] validate_chain kernel/locking/lockdep.c:2251 [inline] __lock_acquire+0xef2/0x3430 kernel/locking/lockdep.c:3340 lock_acquire+0x2a1/0x630 kernel/locking/lockdep.c:3755 lock_sock_nested+0xcb/0x120 net/core/sock.c:2536 lock_sock include/net/sock.h:1460 [inline] sctp_close+0xcd/0x9d0 net/sctp/socket.c:1497 inet_release+0xed/0x1c0 net/ipv4/af_inet.c:425 inet6_release+0x50/0x70 net/ipv6/af_inet6.c:432 sock_release+0x8d/0x1e0 net/socket.c:597 __sock_create+0x38b/0x870 net/socket.c:1226 sock_create+0x7f/0xa0 net/socket.c:1237 sctp_do_peeloff+0x1a2/0x440 net/sctp/socket.c:4879 sctp_getsockopt_peeloff net/sctp/socket.c:4914 [inline] sctp_getsockopt+0x111a/0x67e0 net/sctp/socket.c:6628 sock_common_getsockopt+0x95/0xd0 net/core/sock.c:2690 SYSC_getsockopt net/socket.c:1817 [inline] SyS_getsockopt+0x240/0x380 net/socket.c:1799 entry_SYSCALL_64_fastpath+0x1f/0xc2 This warning is caused by the lock held by sctp_getsockopt() is on one socket, while the other lock that sctp_close() is getting later is on the newly created (which failed) socket during peeloff operation. This patch is to avoid this warning by use lock_sock with subclass SINGLE_DEPTH_NESTING as Wang Cong and Marcelo's suggestion. Reported-by: Dmitry Vyukov <dvyukov@google.com> Suggested-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Suggested-by: Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by: Xin Long <lucien.xin@gmail.com> Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <alexander.levin@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-18fixup: sctp: verify size of a new chunk in _sctp_make_chunk()Greg Kroah-Hartman1-1/+1
Ben writes: > > + int chunklen; > > + > > + chunklen = sizeof(*chunk_hdr) + paylen; > > I think this length still needs to be rounded up (with WORD_ROUND here, > instead of SCTP_PAD4 upstream). So here's a fix for this problem. Reported-by: Ben Hutchings <ben.hutchings@codethink.co.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-11sctp: verify size of a new chunk in _sctp_make_chunk()Alexey Kodanev1-2/+6
[ Upstream commit 07f2c7ab6f8d0a7e7c5764c4e6cc9c52951b9d9c ] When SCTP makes INIT or INIT_ACK packet the total chunk length can exceed SCTP_MAX_CHUNK_LEN which leads to kernel panic when transmitting these packets, e.g. the crash on sending INIT_ACK: [ 597.804948] skbuff: skb_over_panic: text:00000000ffae06e4 len:120168 put:120156 head:000000007aa47635 data:00000000d991c2de tail:0x1d640 end:0xfec0 dev:<NULL> ... [ 597.976970] ------------[ cut here ]------------ [ 598.033408] kernel BUG at net/core/skbuff.c:104! [ 600.314841] Call Trace: [ 600.345829] <IRQ> [ 600.371639] ? sctp_packet_transmit+0x2095/0x26d0 [sctp] [ 600.436934] skb_put+0x16c/0x200 [ 600.477295] sctp_packet_transmit+0x2095/0x26d0 [sctp] [ 600.540630] ? sctp_packet_config+0x890/0x890 [sctp] [ 600.601781] ? __sctp_packet_append_chunk+0x3b4/0xd00 [sctp] [ 600.671356] ? sctp_cmp_addr_exact+0x3f/0x90 [sctp] [ 600.731482] sctp_outq_flush+0x663/0x30d0 [sctp] [ 600.788565] ? sctp_make_init+0xbf0/0xbf0 [sctp] [ 600.845555] ? sctp_check_transmitted+0x18f0/0x18f0 [sctp] [ 600.912945] ? sctp_outq_tail+0x631/0x9d0 [sctp] [ 600.969936] sctp_cmd_interpreter.isra.22+0x3be1/0x5cb0 [sctp] [ 601.041593] ? sctp_sf_do_5_1B_init+0x85f/0xc30 [sctp] [ 601.104837] ? sctp_generate_t1_cookie_event+0x20/0x20 [sctp] [ 601.175436] ? sctp_eat_data+0x1710/0x1710 [sctp] [ 601.233575] sctp_do_sm+0x182/0x560 [sctp] [ 601.284328] ? sctp_has_association+0x70/0x70 [sctp] [ 601.345586] ? sctp_rcv+0xef4/0x32f0 [sctp] [ 601.397478] ? sctp6_rcv+0xa/0x20 [sctp] ... Here the chunk size for INIT_ACK packet becomes too big, mostly because of the state cookie (INIT packet has large size with many address parameters), plus additional server parameters. Later this chunk causes the panic in skb_put_data(): skb_packet_transmit() sctp_packet_pack() skb_put_data(nskb, chunk->skb->data, chunk->skb->len); 'nskb' (head skb) was previously allocated with packet->size from u16 'chunk->chunk_hdr->length'. As suggested by Marcelo we should check the chunk's length in _sctp_make_chunk() before trying to allocate skb for it and discard a chunk if its size bigger than SCTP_MAX_CHUNK_LEN. Signed-off-by: Alexey Kodanev <alexey.kodanev@oracle.com> Acked-by: Marcelo Ricardo Leitner <marcelo.leinter@gmail.com> Acked-by: Neil Horman <nhorman@tuxdriver.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-11sctp: fix dst refcnt leak in sctp_v6_get_dst()Alexey Kodanev1-3/+7
[ Upstream commit 957d761cf91cdbb175ad7d8f5472336a4d54dbf2 ] When going through the bind address list in sctp_v6_get_dst() and the previously found address is better ('matchlen > bmatchlen'), the code continues to the next iteration without releasing currently held destination. Fix it by releasing 'bdst' before continue to the next iteration, and instead of introducing one more '!IS_ERR(bdst)' check for dst_release(), move the already existed one right after ip6_dst_lookup_flow(), i.e. we shouldn't proceed further if we get an error for the route lookup. Fixes: dbc2b5e9a09e ("sctp: fix src address selection if using secondary addresses for ipv6") Signed-off-by: Alexey Kodanev <alexey.kodanev@oracle.com> Acked-by: Neil Horman <nhorman@tuxdriver.com> Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-11sctp: fix dst refcnt leak in sctp_v4_get_dstTommi Rantala1-6/+4
[ Upstream commit 4a31a6b19f9ddf498c81f5c9b089742b7472a6f8 ] Fix dst reference count leak in sctp_v4_get_dst() introduced in commit 410f03831 ("sctp: add routing output fallback"): When walking the address_list, successive ip_route_output_key() calls may return the same rt->dst with the reference incremented on each call. The code would not decrement the dst refcount when the dst pointer was identical from the previous iteration, causing the dst refcnt leak. Testcase: ip netns add TEST ip netns exec TEST ip link set lo up ip link add dummy0 type dummy ip link add dummy1 type dummy ip link add dummy2 type dummy ip link set dev dummy0 netns TEST ip link set dev dummy1 netns TEST ip link set dev dummy2 netns TEST ip netns exec TEST ip addr add 192.168.1.1/24 dev dummy0 ip netns exec TEST ip link set dummy0 up ip netns exec TEST ip addr add 192.168.1.2/24 dev dummy1 ip netns exec TEST ip link set dummy1 up ip netns exec TEST ip addr add 192.168.1.3/24 dev dummy2 ip netns exec TEST ip link set dummy2 up ip netns exec TEST sctp_test -H 192.168.1.2 -P 20002 -h 192.168.1.1 -p 20000 -s -B 192.168.1.3 ip netns del TEST In 4.4 and 4.9 kernels this results to: [ 354.179591] unregister_netdevice: waiting for lo to become free. Usage count = 1 [ 364.419674] unregister_netdevice: waiting for lo to become free. Usage count = 1 [ 374.663664] unregister_netdevice: waiting for lo to become free. Usage count = 1 [ 384.903717] unregister_netdevice: waiting for lo to become free. Usage count = 1 [ 395.143724] unregister_netdevice: waiting for lo to become free. Usage count = 1 [ 405.383645] unregister_netdevice: waiting for lo to become free. Usage count = 1 ... Fixes: 410f03831 ("sctp: add routing output fallback") Fixes: 0ca50d12f ("sctp: fix src address selection if using secondary addresses") Signed-off-by: Tommi Rantala <tommi.t.rantala@nokia.com> Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Acked-by: Neil Horman <nhorman@tuxdriver.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-03sctp: make use of pre-calculated lenMarcelo Ricardo Leitner1-6/+10
[ Upstream commit c76f97c99ae6d26d14c7f0e50e074382bfbc9f98 ] Some sockopt handling functions were calculating the length of the buffer to be written to userspace and then calculating it again when actually writing the buffer, which could lead to some write not using an up-to-date length. This patch updates such places to just make use of the len variable. Also, replace some sizeof(type) to sizeof(var). Signed-off-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <alexander.levin@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-01-31sctp: return error if the asoc has been peeled off in sctp_wait_for_sndbufXin Long1-10/+6
[ Upstream commit a0ff660058b88d12625a783ce9e5c1371c87951f ] After commit cea0cc80a677 ("sctp: use the right sk after waking up from wait_buf sleep"), it may change to lock another sk if the asoc has been peeled off in sctp_wait_for_sndbuf. However, the asoc's new sk could be already closed elsewhere, as it's in the sendmsg context of the old sk that can't avoid the new sk's closing. If the sk's last one refcnt is held by this asoc, later on after putting this asoc, the new sk will be freed, while under it's own lock. This patch is to revert that commit, but fix the old issue by returning error under the old sk's lock. Fixes: cea0cc80a677 ("sctp: use the right sk after waking up from wait_buf sleep") Reported-by: syzbot+ac6ea7baa4432811eb50@syzkaller.appspotmail.com Signed-off-by: Xin Long <lucien.xin@gmail.com> Acked-by: Neil Horman <nhorman@tuxdriver.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-01-31sctp: do not allow the v4 socket to bind a v4mapped v6 addressXin Long1-8/+6
[ Upstream commit c5006b8aa74599ce19104b31d322d2ea9ff887cc ] The check in sctp_sockaddr_af is not robust enough to forbid binding a v4mapped v6 addr on a v4 socket. The worse thing is that v4 socket's bind_verify would not convert this v4mapped v6 addr to a v4 addr. syzbot even reported a crash as the v4 socket bound a v6 addr. This patch is to fix it by doing the common sa.sa_family check first, then AF_INET check for v4mapped v6 addrs. Fixes: 7dab83de50c7 ("sctp: Support ipv6only AF_INET6 sockets.") Reported-by: syzbot+7b7b518b1228d2743963@syzkaller.appspotmail.com Acked-by: Neil Horman <nhorman@tuxdriver.com> Signed-off-by: Xin Long <lucien.xin@gmail.com> Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-01-02sctp: Replace use of sockets_allocated with specified macro.Tonghao Zhang1-2/+2
[ Upstream commit 8cb38a602478e9f806571f6920b0a3298aabf042 ] The patch(180d8cd942ce) replaces all uses of struct sock fields' memory_pressure, memory_allocated, sockets_allocated, and sysctl_mem to accessor macros. But the sockets_allocated field of sctp sock is not replaced at all. Then replace it now for unifying the code. Fixes: 180d8cd942ce ("foundations of per-cgroup memory pressure controlling.") Cc: Glauber Costa <glommer@parallels.com> Signed-off-by: Tonghao Zhang <zhangtonghao@didichuxing.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-12-16sctp: use the right sk after waking up from wait_buf sleepXin Long1-10/+11
[ Upstream commit cea0cc80a6777beb6eb643d4ad53690e1ad1d4ff ] Commit dfcb9f4f99f1 ("sctp: deny peeloff operation on asocs with threads sleeping on it") fixed the race between peeloff and wait sndbuf by checking waitqueue_active(&asoc->wait) in sctp_do_peeloff(). But it actually doesn't work, as even if waitqueue_active returns false the waiting sndbuf thread may still not yet hold sk lock. After asoc is peeled off, sk is not asoc->base.sk any more, then to hold the old sk lock couldn't make assoc safe to access. This patch is to fix this by changing to hold the new sk lock if sk is not asoc->base.sk, meanwhile, also set the sk in sctp_sendmsg with the new sk. With this fix, there is no more race between peeloff and waitbuf, the check 'waitqueue_active' in sctp_do_peeloff can be removed. Thanks Marcelo and Neil for making this clear. v1->v2: fix it by changing to lock the new sock instead of adding a flag in asoc. Suggested-by: Neil Horman <nhorman@tuxdriver.com> Signed-off-by: Xin Long <lucien.xin@gmail.com> Acked-by: Neil Horman <nhorman@tuxdriver.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <alexander.levin@verizon.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-12-16sctp: do not free asoc when it is already dead in sctp_sendmsgXin Long1-3/+14
[ Upstream commit ca3af4dd28cff4e7216e213ba3b671fbf9f84758 ] Now in sctp_sendmsg sctp_wait_for_sndbuf could schedule out without holding sock sk. It means the current asoc can be freed elsewhere, like when receiving an abort packet. If the asoc is just created in sctp_sendmsg and sctp_wait_for_sndbuf returns err, the asoc will be freed again due to new_asoc is not nil. An use-after-free issue would be triggered by this. This patch is to fix it by setting new_asoc with nil if the asoc is already dead when cpu schedules back, so that it will not be freed again in sctp_sendmsg. v1->v2: set new_asoc as nil in sctp_sendmsg instead of sctp_wait_for_sndbuf. Suggested-by: Neil Horman <nhorman@tuxdriver.com> Reported-by: Dmitry Vyukov <dvyukov@google.com> Signed-off-by: Xin Long <lucien.xin@gmail.com> Acked-by: Neil Horman <nhorman@tuxdriver.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <alexander.levin@verizon.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-12-09net: sctp: fix array overrun read on sctp_timer_tblColin Ian King1-1/+1
[ Upstream commit 0e73fc9a56f22f2eec4d2b2910c649f7af67b74d ] The comparison on the timeout can lead to an array overrun read on sctp_timer_tbl because of an off-by-one error. Fix this by using < instead of <= and also compare to the array size rather than SCTP_EVENT_TIMEOUT_MAX. Fixes CoverityScan CID#1397639 ("Out-of-bounds read") Signed-off-by: Colin Ian King <colin.king@canonical.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <alexander.levin@verizon.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-30Revert "sctp: do not peel off an assoc from one netns to another one"Greg Kroah-Hartman1-4/+0
This reverts commit 2a0e60907e54dad75e9b3568d02bec11d6e74f6b which is commit df80cd9b28b9ebaa284a41df611dbf3a2d05ca74 upstream as I messed up by applying it to the tree twice. Reported-by: Michal Kubecek <mkubecek@suse.cz> Cc: ChunYu Wang <chunwang@redhat.com> Cc: Xin Long <lucien.xin@gmail.com> Cc: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Cc: Neil Horman <nhorman@tuxdriver.com> Cc: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-24net/sctp: Always set scope_id in sctp_inet6_skb_msgnameEric W. Biederman1-0/+2
[ Upstream commit 7c8a61d9ee1df0fb4747879fa67a99614eb62fec ] Alexandar Potapenko while testing the kernel with KMSAN and syzkaller discovered that in some configurations sctp would leak 4 bytes of kernel stack. Working with his reproducer I discovered that those 4 bytes that are leaked is the scope id of an ipv6 address returned by recvmsg. With a little code inspection and a shrewd guess I discovered that sctp_inet6_skb_msgname only initializes the scope_id field for link local ipv6 addresses to the interface index the link local address pertains to instead of initializing the scope_id field for all ipv6 addresses. That is almost reasonable as scope_id's are meaniningful only for link local addresses. Set the scope_id in all other cases to 0 which is not a valid interface index to make it clear there is nothing useful in the scope_id field. There should be no danger of breaking userspace as the stack leak guaranteed that previously meaningless random data was being returned. Fixes: 372f525b495c ("SCTP: Resync with LKSCTP tree.") History-tree: https://git.kernel.org/pub/scm/linux/kernel/git/tglx/history.git Reported-by: Alexander Potapenko <glider@google.com> Tested-by: Alexander Potapenko <glider@google.com> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-24sctp: do not peel off an assoc from one netns to another oneXin Long1-0/+4
[ Upstream commit df80cd9b28b9ebaa284a41df611dbf3a2d05ca74 ] Now when peeling off an association to the sock in another netns, all transports in this assoc are not to be rehashed and keep use the old key in hashtable. As a transport uses sk->net as the hash key to insert into hashtable, it would miss removing these transports from hashtable due to the new netns when closing the sock and all transports are being freeed, then later an use-after-free issue could be caused when looking up an asoc and dereferencing those transports. This is a very old issue since very beginning, ChunYu found it with syzkaller fuzz testing with this series: socket$inet6_sctp() bind$inet6() sendto$inet6() unshare(0x40000000) getsockopt$inet_sctp6_SCTP_GET_ASSOC_ID_LIST() getsockopt$inet_sctp6_SCTP_SOCKOPT_PEELOFF() This patch is to block this call when peeling one assoc off from one netns to another one, so that the netns of all transport would not go out-sync with the key in hashtable. Note that this patch didn't fix it by rehashing transports, as it's difficult to handle the situation when the tuple is already in use in the new netns. Besides, no one would like to peel off one assoc to another netns, considering ipaddrs, ifaces, etc. are usually different. Reported-by: ChunYu Wang <chunwang@redhat.com> Signed-off-by: Xin Long <lucien.xin@gmail.com> Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Acked-by: Neil Horman <nhorman@tuxdriver.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-21sctp: do not peel off an assoc from one netns to another oneXin Long1-0/+4
commit df80cd9b28b9ebaa284a41df611dbf3a2d05ca74 upstream. Now when peeling off an association to the sock in another netns, all transports in this assoc are not to be rehashed and keep use the old key in hashtable. As a transport uses sk->net as the hash key to insert into hashtable, it would miss removing these transports from hashtable due to the new netns when closing the sock and all transports are being freeed, then later an use-after-free issue could be caused when looking up an asoc and dereferencing those transports. This is a very old issue since very beginning, ChunYu found it with syzkaller fuzz testing with this series: socket$inet6_sctp() bind$inet6() sendto$inet6() unshare(0x40000000) getsockopt$inet_sctp6_SCTP_GET_ASSOC_ID_LIST() getsockopt$inet_sctp6_SCTP_SOCKOPT_PEELOFF() This patch is to block this call when peeling one assoc off from one netns to another one, so that the netns of all transport would not go out-sync with the key in hashtable. Note that this patch didn't fix it by rehashing transports, as it's difficult to handle the situation when the tuple is already in use in the new netns. Besides, no one would like to peel off one assoc to another netns, considering ipaddrs, ifaces, etc. are usually different. Reported-by: ChunYu Wang <chunwang@redhat.com> Signed-off-by: Xin Long <lucien.xin@gmail.com> Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Acked-by: Neil Horman <nhorman@tuxdriver.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben.hutchings@codethink.co.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-18sctp: reset owner sk for data chunks on out queues when migrating a sockXin Long1-0/+32
[ Upstream commit d04adf1b355181e737b6b1e23d801b07f0b7c4c0 ] Now when migrating sock to another one in sctp_sock_migrate(), it only resets owner sk for the data in receive queues, not the chunks on out queues. It would cause that data chunks length on the sock is not consistent with sk sk_wmem_alloc. When closing the sock or freeing these chunks, the old sk would never be freed, and the new sock may crash due to the overflow sk_wmem_alloc. syzbot found this issue with this series: r0 = socket$inet_sctp() sendto$inet(r0) listen(r0) accept4(r0) close(r0) Although listen() should have returned error when one TCP-style socket is in connecting (I may fix this one in another patch), it could also be reproduced by peeling off an assoc. This issue is there since very beginning. This patch is to reset owner sk for the chunks on out queues so that sk sk_wmem_alloc has correct value after accept one sock or peeloff an assoc to one sock. Note that when resetting owner sk for chunks on outqueue, it has to sctp_clear_owner_w/skb_orphan chunks before changing assoc->base.sk first and then sctp_set_owner_w them after changing assoc->base.sk, due to that sctp_wfree and it's callees are using assoc->base.sk. Reported-by: Dmitry Vyukov <dvyukov@google.com> Signed-off-by: Xin Long <lucien.xin@gmail.com> Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-18sctp: add the missing sock_owned_by_user check in sctp_icmp_redirectXin Long1-1/+1
[ Upstream commit 1cc276cec9ec574d41cf47dfc0f51406b6f26ab4 ] Now sctp processes icmp redirect packet in sctp_icmp_redirect where it calls sctp_transport_dst_check in which tp->dst can be released. The problem is before calling sctp_transport_dst_check, it doesn't check sock_owned_by_user, which means tp->dst could be freed while a process is accessing it with owning the socket. An use-after-free issue could be triggered by this. This patch is to fix it by checking sock_owned_by_user before calling sctp_transport_dst_check in sctp_icmp_redirect, so that it would not release tp->dst if users still hold sock lock. Besides, the same issue fixed in commit 45caeaa5ac0b ("dccp/tcp: fix routing redirect race") on sctp also needs this check. Fixes: 55be7a9c6074 ("ipv4: Add redirect support to all protocol icmp error handlers") Reported-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Xin Long <lucien.xin@gmail.com> Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Acked-by: Neil Horman <nhorman@tuxdriver.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-08-30sctp: fully initialize the IPv6 address in sctp_v6_to_addr()Alexander Potapenko1-0/+2
[ Upstream commit 15339e441ec46fbc3bf3486bb1ae4845b0f1bb8d ] KMSAN reported use of uninitialized sctp_addr->v4.sin_addr.s_addr and sctp_addr->v6.sin6_scope_id in sctp_v6_cmp_addr() (see below). Make sure all fields of an IPv6 address are initialized, which guarantees that the IPv4 fields are also initialized. ================================================================== BUG: KMSAN: use of uninitialized memory in sctp_v6_cmp_addr+0x8d4/0x9f0 net/sctp/ipv6.c:517 CPU: 2 PID: 31056 Comm: syz-executor1 Not tainted 4.11.0-rc5+ #2944 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011 Call Trace: dump_stack+0x172/0x1c0 lib/dump_stack.c:42 is_logbuf_locked mm/kmsan/kmsan.c:59 [inline] kmsan_report+0x12a/0x180 mm/kmsan/kmsan.c:938 native_save_fl arch/x86/include/asm/irqflags.h:18 [inline] arch_local_save_flags arch/x86/include/asm/irqflags.h:72 [inline] arch_local_irq_save arch/x86/include/asm/irqflags.h:113 [inline] __msan_warning_32+0x61/0xb0 mm/kmsan/kmsan_instr.c:467 sctp_v6_cmp_addr+0x8d4/0x9f0 net/sctp/ipv6.c:517 sctp_v6_get_dst+0x8c7/0x1630 net/sctp/ipv6.c:290 sctp_transport_route+0x101/0x570 net/sctp/transport.c:292 sctp_assoc_add_peer+0x66d/0x16f0 net/sctp/associola.c:651 sctp_sendmsg+0x35a5/0x4f90 net/sctp/socket.c:1871 inet_sendmsg+0x498/0x670 net/ipv4/af_inet.c:762 sock_sendmsg_nosec net/socket.c:633 [inline] sock_sendmsg net/socket.c:643 [inline] SYSC_sendto+0x608/0x710 net/socket.c:1696 SyS_sendto+0x8a/0xb0 net/socket.c:1664 entry_SYSCALL_64_fastpath+0x13/0x94 RIP: 0033:0x44b479 RSP: 002b:00007f6213f21c08 EFLAGS: 00000286 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 0000000020000000 RCX: 000000000044b479 RDX: 0000000000000041 RSI: 0000000020edd000 RDI: 0000000000000006 RBP: 00000000007080a8 R08: 0000000020b85fe4 R09: 000000000000001c R10: 0000000000040005 R11: 0000000000000286 R12: 00000000ffffffff R13: 0000000000003760 R14: 00000000006e5820 R15: 0000000000ff8000 origin description: ----dst_saddr@sctp_v6_get_dst local variable created at: sk_fullsock include/net/sock.h:2321 [inline] inet6_sk include/linux/ipv6.h:309 [inline] sctp_v6_get_dst+0x91/0x1630 net/sctp/ipv6.c:241 sctp_transport_route+0x101/0x570 net/sctp/transport.c:292 ================================================================== BUG: KMSAN: use of uninitialized memory in sctp_v6_cmp_addr+0x8d4/0x9f0 net/sctp/ipv6.c:517 CPU: 2 PID: 31056 Comm: syz-executor1 Not tainted 4.11.0-rc5+ #2944 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011 Call Trace: dump_stack+0x172/0x1c0 lib/dump_stack.c:42 is_logbuf_locked mm/kmsan/kmsan.c:59 [inline] kmsan_report+0x12a/0x180 mm/kmsan/kmsan.c:938 native_save_fl arch/x86/include/asm/irqflags.h:18 [inline] arch_local_save_flags arch/x86/include/asm/irqflags.h:72 [inline] arch_local_irq_save arch/x86/include/asm/irqflags.h:113 [inline] __msan_warning_32+0x61/0xb0 mm/kmsan/kmsan_instr.c:467 sctp_v6_cmp_addr+0x8d4/0x9f0 net/sctp/ipv6.c:517 sctp_v6_get_dst+0x8c7/0x1630 net/sctp/ipv6.c:290 sctp_transport_route+0x101/0x570 net/sctp/transport.c:292 sctp_assoc_add_peer+0x66d/0x16f0 net/sctp/associola.c:651 sctp_sendmsg+0x35a5/0x4f90 net/sctp/socket.c:1871 inet_sendmsg+0x498/0x670 net/ipv4/af_inet.c:762 sock_sendmsg_nosec net/socket.c:633 [inline] sock_sendmsg net/socket.c:643 [inline] SYSC_sendto+0x608/0x710 net/socket.c:1696 SyS_sendto+0x8a/0xb0 net/socket.c:1664 entry_SYSCALL_64_fastpath+0x13/0x94 RIP: 0033:0x44b479 RSP: 002b:00007f6213f21c08 EFLAGS: 00000286 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 0000000020000000 RCX: 000000000044b479 RDX: 0000000000000041 RSI: 0000000020edd000 RDI: 0000000000000006 RBP: 00000000007080a8 R08: 0000000020b85fe4 R09: 000000000000001c R10: 0000000000040005 R11: 0000000000000286 R12: 00000000ffffffff R13: 0000000000003760 R14: 00000000006e5820 R15: 0000000000ff8000 origin description: ----dst_saddr@sctp_v6_get_dst local variable created at: sk_fullsock include/net/sock.h:2321 [inline] inet6_sk include/linux/ipv6.h:309 [inline] sctp_v6_get_dst+0x91/0x1630 net/sctp/ipv6.c:241 sctp_transport_route+0x101/0x570 net/sctp/transport.c:292 ================================================================== Signed-off-by: Alexander Potapenko <glider@google.com> Reviewed-by: Xin Long <lucien.xin@gmail.com> Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-05sctp: check af before verify address in sctp_addr_id2transportXin Long1-1/+1
[ Upstream commit 912964eacb111551db73429719eb5fadcab0ff8a ] Commit 6f29a1306131 ("sctp: sctp_addr_id2transport should verify the addr before looking up assoc") invoked sctp_verify_addr to verify the addr. But it didn't check af variable beforehand, once users pass an address with family = 0 through sockopt, sctp_get_af_specific will return NULL and NULL pointer dereference will be caused by af->sockaddr_len. This patch is to fix it by returning NULL if af variable is NULL. Fixes: 6f29a1306131 ("sctp: sctp_addr_id2transport should verify the addr before looking up assoc") Signed-off-by: Xin Long <lucien.xin@gmail.com> Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <alexander.levin@verizon.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-17sctp: sctp_addr_id2transport should verify the addr before looking up assocXin Long1-1/+5
[ Upstream commit 6f29a130613191d3c6335169febe002cba00edf5 ] sctp_addr_id2transport is a function for sockopt to look up assoc by address. As the address is from userspace, it can be a v4-mapped v6 address. But in sctp protocol stack, it always handles a v4-mapped v6 address as a v4 address. So it's necessary to convert it to a v4 address before looking up assoc by address. This patch is to fix it by calling sctp_verify_addr in which it can do this conversion before calling sctp_endpoint_lookup_assoc, just like what sctp_sendmsg and __sctp_connect do for the address from users. Signed-off-by: Xin Long <lucien.xin@gmail.com> Acked-by: Neil Horman <nhorman@tuxdriver.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <alexander.levin@verizon.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-07sctp: fix ICMP processing if skb is non-linearDavide Caratti1-7/+9
[ Upstream commit 804ec7ebe8ea003999ca8d1bfc499edc6a9e07df ] sometimes ICMP replies to INIT chunks are ignored by the client, even if the encapsulated SCTP headers match an open socket. This happens when the ICMP packet is carried by a paged skb: use skb_header_pointer() to read packet contents beyond the SCTP header, so that chunk header and initiate tag are validated correctly. v2: - don't use skb_header_pointer() to read the transport header, since icmp_socket_deliver() already puts these 8 bytes in the linear area. - change commit message to make specific reference to INIT chunks. Signed-off-by: Davide Caratti <dcaratti@redhat.com> Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Acked-by: Vlad Yasevich <vyasevich@gmail.com> Reviewed-by: Xin Long <lucien.xin@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-07sctp: do not inherit ipv6_{mc|ac|fl}_list from parentEric Dumazet1-0/+3
[ Upstream commit fdcee2cbb8438702ea1b328fb6e0ac5e9a40c7f8 ] SCTP needs fixes similar to 83eaddab4378 ("ipv6/dccp: do not inherit ipv6_mc_list from parent"), otherwise bad things can happen. Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Andrey Konovalov <andreyknvl@google.com> Tested-by: Andrey Konovalov <andreyknvl@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-07sctp: fix src address selection if using secondary addresses for ipv6Xin Long1-17/+29
[ Upstream commit dbc2b5e9a09e9a6664679a667ff81cff6e5f2641 ] Commit 0ca50d12fe46 ("sctp: fix src address selection if using secondary addresses") has fixed a src address selection issue when using secondary addresses for ipv4. Now sctp ipv6 also has the similar issue. When using a secondary address, sctp_v6_get_dst tries to choose the saddr which has the most same bits with the daddr by sctp_v6_addr_match_len. It may make some cases not work as expected. hostA: [1] fd21:356b:459a:cf10::11 (eth1) [2] fd21:356b:459a:cf20::11 (eth2) hostB: [a] fd21:356b:459a:cf30::2 (eth1) [b] fd21:356b:459a:cf40::2 (eth2) route from hostA to hostB: fd21:356b:459a:cf30::/64 dev eth1 metric 1024 mtu 1500 The expected path should be: fd21:356b:459a:cf10::11 <-> fd21:356b:459a:cf30::2 But addr[2] matches addr[a] more bits than addr[1] does, according to sctp_v6_addr_match_len. It causes the path to be: fd21:356b:459a:cf20::11 <-> fd21:356b:459a:cf30::2 This patch is to fix it with the same way as Marcelo's fix for sctp ipv4. As no ip_dev_find for ipv6, this patch is to use ipv6_chk_addr to check if the saddr is in a dev instead. Note that for backwards compatibility, it will still do the addr_match_len check here when no optimal is found. Reported-by: Patrick Talbert <ptalbert@redhat.com> Signed-off-by: Xin Long <lucien.xin@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-03sctp: listen on the sock only when it's state is listening or closedXin Long1-0/+3
[ Upstream commit 34b2789f1d9bf8dcca9b5cb553d076ca2cd898ee ] Now sctp doesn't check sock's state before listening on it. It could even cause changing a sock with any state to become a listening sock when doing sctp_listen. This patch is to fix it by checking sock's state in sctp_listen, so that it will listen on the sock with right state. Reported-by: Andrey Konovalov <andreyknvl@google.com> Tested-by: Andrey Konovalov <andreyknvl@google.com> Signed-off-by: Xin Long <lucien.xin@gmail.com> Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-04-21sctp: deny peeloff operation on asocs with threads sleeping on itMarcelo Ricardo Leitner1-2/+6
commit dfcb9f4f99f1e9a49e43398a7bfbf56927544af1 upstream. commit 2dcab5984841 ("sctp: avoid BUG_ON on sctp_wait_for_sndbuf") attempted to avoid a BUG_ON call when the association being used for a sendmsg() is blocked waiting for more sndbuf and another thread did a peeloff operation on such asoc, moving it to another socket. As Ben Hutchings noticed, then in such case it would return without locking back the socket and would cause two unlocks in a row. Further analysis also revealed that it could allow a double free if the application managed to peeloff the asoc that is created during the sendmsg call, because then sctp_sendmsg() would try to free the asoc that was created only for that call. This patch takes another approach. It will deny the peeloff operation if there is a thread sleeping on the asoc, so this situation doesn't exist anymore. This avoids the issues described above and also honors the syscalls that are already being handled (it can be multiple sendmsg calls). Joint work with Xin Long. Fixes: 2dcab5984841 ("sctp: avoid BUG_ON on sctp_wait_for_sndbuf") Cc: Alexander Popov <alex.popov@linux.com> Cc: Ben Hutchings <ben@decadent.org.uk> Signed-off-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Signed-off-by: Xin Long <lucien.xin@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-02-18sctp: avoid BUG_ON on sctp_wait_for_sndbufMarcelo Ricardo Leitner1-1/+2
[ Upstream commit 2dcab598484185dea7ec22219c76dcdd59e3cb90 ] Alexander Popov reported that an application may trigger a BUG_ON in sctp_wait_for_sndbuf if the socket tx buffer is full, a thread is waiting on it to queue more data and meanwhile another thread peels off the association being used by the first thread. This patch replaces the BUG_ON call with a proper error handling. It will return -EPIPE to the original sendmsg call, similarly to what would have been done if the association wasn't found in the first place. Acked-by: Alexander Popov <alex.popov@linux.com> Signed-off-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Reviewed-by: Xin Long <lucien.xin@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-11-21sctp: assign assoc_id earlier in __sctp_connectMarcelo Ricardo Leitner1-2/+5
[ Upstream commit 7233bc84a3aeda835d334499dc00448373caf5c0 ] sctp_wait_for_connect() currently already holds the asoc to keep it alive during the sleep, in case another thread release it. But Andrey Konovalov and Dmitry Vyukov reported an use-after-free in such situation. Problem is that __sctp_connect() doesn't get a ref on the asoc and will do a read on the asoc after calling sctp_wait_for_connect(), but by then another thread may have closed it and the _put on sctp_wait_for_connect will actually release it, causing the use-after-free. Fix is, instead of doing the read after waiting for the connect, do it before so, and avoid this issue as the socket is still locked by then. There should be no issue on returning the asoc id in case of failure as the application shouldn't trust on that number in such situations anyway. This issue doesn't exist in sctp_sendmsg() path. Reported-by: Dmitry Vyukov <dvyukov@google.com> Reported-by: Andrey Konovalov <andreyknvl@google.com> Tested-by: Andrey Konovalov <andreyknvl@google.com> Signed-off-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Reviewed-by: Xin Long <lucien.xin@gmail.com> Acked-by: Neil Horman <nhorman@tuxdriver.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-11-15sctp: validate chunk len before actually using itMarcelo Ricardo Leitner1-6/+6
[ Upstream commit bf911e985d6bbaa328c20c3e05f4eb03de11fdd6 ] Andrey Konovalov reported that KASAN detected that SCTP was using a slab beyond the boundaries. It was caused because when handling out of the blue packets in function sctp_sf_ootb() it was checking the chunk len only after already processing the first chunk, validating only for the 2nd and subsequent ones. The fix is to just move the check upwards so it's also validated for the 1st chunk. Reported-by: Andrey Konovalov <andreyknvl@google.com> Tested-by: Andrey Konovalov <andreyknvl@google.com> Signed-off-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Reviewed-by: Xin Long <lucien.xin@gmail.com> Acked-by: Neil Horman <nhorman@tuxdriver.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>