talos-obmc-linux/net/tipc, branch dev-5.0

tipc: fix cancellation of topology subscriptions

2019-04-03T04:27:25+00:00

[ Upstream commit 33872d79f5d1cbedaaab79669cc38f16097a9450 ] When cancelling a subscription, we have to clear the cancel bit in the request before iterating over any established subscriptions with memcmp. Otherwise no subscription will ever be found, and it will not be possible to explicitly unsubscribe individual subscriptions. Fixes: 8985ecc7c1e0 ("tipc: simplify endianness handling in topology subscriber") Signed-off-by: Erik Hugne Signed-off-by: Jon Maloy Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

tipc: change to check tipc_own_id to return in tipc_net_stop

2019-04-03T04:27:25+00:00

[ Upstream commit 9926cb5f8b0f0aea535735185600d74db7608550 ] When running a syz script, a panic occurred: [ 156.088228] BUG: KASAN: use-after-free in tipc_disc_timeout+0x9c9/0xb20 [tipc] [ 156.094315] Call Trace: [ 156.094844] [ 156.095306] dump_stack+0x7c/0xc0 [ 156.097346] print_address_description+0x65/0x22e [ 156.100445] kasan_report.cold.3+0x37/0x7a [ 156.102402] tipc_disc_timeout+0x9c9/0xb20 [tipc] [ 156.106517] call_timer_fn+0x19a/0x610 [ 156.112749] run_timer_softirq+0xb51/0x1090 It was caused by the netns freed without deleting the discoverer timer, while later on the netns would be accessed in the timer handler. The timer should have been deleted by tipc_net_stop() when cleaning up a netns. However, tipc has been able to enable a bearer and start d->timer without the local node_addr set since Commit 52dfae5c85a4 ("tipc: obtain node identity from interface by default"), which caused the timer not to be deleted in tipc_net_stop() then. So fix it in tipc_net_stop() by changing to check local node_id instead of local node_addr, as Jon suggested. While at it, remove the calling of tipc_nametbl_withdraw() there, since tipc_nametbl_stop() will take of the nametbl's freeing after. Fixes: 52dfae5c85a4 ("tipc: obtain node identity from interface by default") Reported-by: syzbot+a25307ad099309f1c2b9@syzkaller.appspotmail.com Signed-off-by: Xin Long Acked-by: Ying Xue Acked-by: Jon Maloy Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

tipc: allow service ranges to be connect()'ed on RDM/DGRAM

2019-04-03T04:27:25+00:00

[ Upstream commit ea239314fe42ace880bdd834256834679346c80e ] We move the check that prevents connecting service ranges to after the RDM/DGRAM check, and move address sanity control to a separate function that also validates the service range. Fixes: 23998835be98 ("tipc: improve address sanity check in tipc_connect()") Signed-off-by: Erik Hugne Signed-off-by: Jon Maloy Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

tipc: fix RDM/DGRAM connect() regression

2019-03-10T06:09:00+00:00

[ Upstream commit 0e63208915a8d7590d0a6218dadb2a6a00ac705a ] Fix regression bug introduced in commit 365ad353c256 ("tipc: reduce risk of user starvation during link congestion") Only signal -EDESTADDRREQ for RDM/DGRAM if we don't have a cached sockaddr. Fixes: 365ad353c256 ("tipc: reduce risk of user starvation during link congestion") Signed-off-by: Erik Hugne Signed-off-by: Jon Maloy Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

tipc: fix race condition causing hung sendto

2019-02-26T22:50:50+00:00

When sending multicast messages via blocking socket, if sending link is congested (tsk->cong_link_cnt is set to 1), the sending thread will be put into sleeping state. However, tipc_sk_filter_rcv() is called under socket spin lock but tipc_wait_for_cond() is not. So, there is no guarantee that the setting of tsk->cong_link_cnt to 0 in tipc_sk_proto_rcv() in CPU-1 will be perceived by CPU-0. If that is the case, the sending thread in CPU-0 after being waken up, will continue to see tsk->cong_link_cnt as 1 and put the sending thread into sleeping state again. The sending thread will sleep forever. CPU-0 | CPU-1 tipc_wait_for_cond() | { | // condition_ = !tsk->cong_link_cnt | while ((rc_ = !(condition_))) { | ... | release_sock(sk_); | wait_woken(); | | if (!sock_owned_by_user(sk)) | tipc_sk_filter_rcv() | { | ... | tipc_sk_proto_rcv() | { | ... | tsk->cong_link_cnt--; | ... | sk->sk_write_space(sk); | ... | } | ... | } sched_annotate_sleep(); | lock_sock(sk_); | remove_wait_queue(); | } | } | This commit fixes it by adding memory barrier to tipc_sk_proto_rcv() and tipc_wait_for_cond(). Acked-by: Jon Maloy Signed-off-by: Tung Nguyen Signed-off-by: David S. Miller

tipc: improve function tipc_wait_for_rcvmsg()

2019-02-21T21:58:05+00:00

This commit replaces schedule_timeout() with wait_woken() in function tipc_wait_for_rcvmsg(). wait_woken() uses memory barriers in its implementation to avoid potential race condition when putting a process into sleeping state and then waking it up. Acked-by: Ying Xue Acked-by: Jon Maloy Signed-off-by: Tung Nguyen Signed-off-by: David S. Miller

tipc: improve function tipc_wait_for_cond()

2019-02-21T21:58:05+00:00

Commit 844cf763fba6 ("tipc: make macro tipc_wait_for_cond() smp safe") replaced finish_wait() with remove_wait_queue() but still used prepare_to_wait(). This causes unnecessary conditional checking before adding to wait queue in prepare_to_wait(). This commit replaces prepare_to_wait() with add_wait_queue() as the pair function with remove_wait_queue(). Acked-by: Ying Xue Acked-by: Jon Maloy Signed-off-by: Tung Nguyen Signed-off-by: David S. Miller

tipc: fix link session and re-establish issues

2019-02-12T05:26:20+00:00

When a link endpoint is re-created (e.g. after a node reboot or interface reset), the link session number is varied by random, the peer endpoint will be synced with this new session number before the link is re-established. However, there is a shortcoming in this mechanism that can lead to the link never re-established or faced with a failure then. It happens when the peer endpoint is ready in ESTABLISHING state, the 'peer_session' as well as the 'in_session' flag have been set, but suddenly this link endpoint leaves. When it comes back with a random session number, there are two situations possible: 1/ If the random session number is larger than (or equal to) the previous one, the peer endpoint will be updated with this new session upon receipt of a RESET_MSG from this endpoint, and the link can be re- established as normal. Otherwise, all the RESET_MSGs from this endpoint will be rejected by the peer. In turn, when this link endpoint receives one ACTIVATE_MSG from the peer, it will move to ESTABLISHED and start to send STATE_MSGs, but again these messages will be dropped by the peer due to wrong session. The peer link endpoint can still become ESTABLISHED after receiving a traffic message from this endpoint (e.g. a BCAST_PROTOCOL or NAME_DISTRIBUTOR), but since all the STATE_MSGs are invalid, the link will be forced down sooner or later! Even in case the random session number is larger than the previous one, it can be that the ACTIVATE_MSG from the peer arrives first, and this link endpoint moves quickly to ESTABLISHED without sending out any RESET_MSG yet. Consequently, the peer link will not be updated with the new session number, and the same link failure scenario as above will happen. 2/ Another situation can be that, the peer link endpoint was reset due to any reasons in the meantime, its link state was set to RESET from ESTABLISHING but still in session, i.e. the 'in_session' flag is not reset... Now, if the random session number from this endpoint is less than the previous one, all the RESET_MSGs from this endpoint will be rejected by the peer. In the other direction, when this link endpoint receives a RESET_MSG from the peer, it moves to ESTABLISHING and starts to send ACTIVATE_MSGs, but all these messages will be rejected by the peer too. As a result, the link cannot be re-established but gets stuck with this link endpoint in state ESTABLISHING and the peer in RESET! Solution: =========== This link endpoint should not go directly to ESTABLISHED when getting ACTIVATE_MSG from the peer which may belong to the old session if the link was re-created. To ensure the session to be correct before the link is re-established, the peer endpoint in ESTABLISHING state will send back the last session number in ACTIVATE_MSG for a verification at this endpoint. Then, if needed, a new and more appropriate session number will be regenerated to force a re-synch first. In addition, when a link in ESTABLISHING state is reset, its state will move to RESET according to the link FSM, along with resetting the 'in_session' flag (and the other data) as a normal link reset, it will also be deleted if requested. The solution is backward compatible. Acked-by: Jon Maloy Acked-by: Ying Xue Signed-off-by: Tuong Lien Signed-off-by: David S. Miller

tipc: fix skb may be leaky in tipc_link_input

2019-02-12T02:35:52+00:00

When we free skb at tipc_data_input, we return a 'false' boolean. Then, skb passed to subcalling tipc_link_input in tipc_link_rcv, 1303 int tipc_link_rcv: ... 1354 if (!tipc_data_input(l, skb, l->inputq)) 1355 rc |= tipc_link_input(l, skb, l->inputq); Fix it by simple changing to a 'true' boolean when skb is being free-ed. Then, tipc_link_rcv will bypassed to subcalling tipc_link_input as above condition. Acked-by: Ying Xue Acked-by: Jon Maloy Signed-off-by: Hoang Le Signed-off-by: David S. Miller

tipc: fix uninit-value in tipc_nl_compat_doit

2019-01-16T04:29:21+00:00

BUG: KMSAN: uninit-value in tipc_nl_compat_doit+0x404/0xa10 net/tipc/netlink_compat.c:335 CPU: 0 PID: 4514 Comm: syz-executor485 Not tainted 4.16.0+ #87 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:683 tipc_nl_compat_doit+0x404/0xa10 net/tipc/netlink_compat.c:335 tipc_nl_compat_recv+0x164b/0x2700 net/tipc/netlink_compat.c:1153 genl_family_rcv_msg net/netlink/genetlink.c:599 [inline] genl_rcv_msg+0x1686/0x1810 net/netlink/genetlink.c:624 netlink_rcv_skb+0x378/0x600 net/netlink/af_netlink.c:2447 genl_rcv+0x63/0x80 net/netlink/genetlink.c:635 netlink_unicast_kernel net/netlink/af_netlink.c:1311 [inline] netlink_unicast+0x166b/0x1740 net/netlink/af_netlink.c:1337 netlink_sendmsg+0x1048/0x1310 net/netlink/af_netlink.c:1900 sock_sendmsg_nosec net/socket.c:630 [inline] sock_sendmsg net/socket.c:640 [inline] ___sys_sendmsg+0xec0/0x1310 net/socket.c:2046 __sys_sendmsg net/socket.c:2080 [inline] SYSC_sendmsg+0x2a3/0x3d0 net/socket.c:2091 SyS_sendmsg+0x54/0x80 net/socket.c:2087 do_syscall_64+0x309/0x430 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x3d/0xa2 RIP: 0033:0x43fda9 RSP: 002b:00007ffd0c184ba8 EFLAGS: 00000213 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 000000000043fda9 RDX: 0000000000000000 RSI: 0000000020023000 RDI: 0000000000000003 RBP: 00000000006ca018 R08: 00000000004002c8 R09: 00000000004002c8 R10: 00000000004002c8 R11: 0000000000000213 R12: 00000000004016d0 R13: 0000000000401760 R14: 0000000000000000 R15: 0000000000000000 Uninit was created at: kmsan_save_stack_with_flags mm/kmsan/kmsan.c:278 [inline] kmsan_internal_poison_shadow+0xb8/0x1b0 mm/kmsan/kmsan.c:188 kmsan_kmalloc+0x94/0x100 mm/kmsan/kmsan.c:314 kmsan_slab_alloc+0x11/0x20 mm/kmsan/kmsan.c:321 slab_post_alloc_hook mm/slab.h:445 [inline] slab_alloc_node mm/slub.c:2737 [inline] __kmalloc_node_track_caller+0xaed/0x11c0 mm/slub.c:4369 __kmalloc_reserve net/core/skbuff.c:138 [inline] __alloc_skb+0x2cf/0x9f0 net/core/skbuff.c:206 alloc_skb include/linux/skbuff.h:984 [inline] netlink_alloc_large_skb net/netlink/af_netlink.c:1183 [inline] netlink_sendmsg+0x9a6/0x1310 net/netlink/af_netlink.c:1875 sock_sendmsg_nosec net/socket.c:630 [inline] sock_sendmsg net/socket.c:640 [inline] ___sys_sendmsg+0xec0/0x1310 net/socket.c:2046 __sys_sendmsg net/socket.c:2080 [inline] SYSC_sendmsg+0x2a3/0x3d0 net/socket.c:2091 SyS_sendmsg+0x54/0x80 net/socket.c:2087 do_syscall_64+0x309/0x430 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x3d/0xa2 In tipc_nl_compat_recv(), when the len variable returned by nlmsg_attrlen() is 0, the message is still treated as a valid one, which is obviously unresonable. When len is zero, it means the message not only doesn't contain any valid TLV payload, but also TLV header is not included. Under this stituation, tlv_type field in TLV header is still accessed in tipc_nl_compat_dumpit() or tipc_nl_compat_doit(), but the field space is obviously illegal. Of course, it is not initialized. Reported-by: syzbot+bca0dc46634781f08b38@syzkaller.appspotmail.com Reported-by: syzbot+6bdb590321a7ae40c1a6@syzkaller.appspotmail.com Signed-off-by: Ying Xue Signed-off-by: David S. Miller