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2022-01-07mptcp: do not block subflows creation on errorsPaolo Abeni
If the MPTCP configuration allows for multiple subflows creation, and the first additional subflows never reach the fully established status - e.g. due to packets drop or reset - the in kernel path manager do not move to the next subflow. This patch introduces a new PM helper to cope with MPJ subflow creation failure and delay and hook it where appropriate. Such helper triggers additional subflow creation, as needed and updates the PM subflow counter, if the current one is closing. Additionally start all the needed additional subflows as soon as the MPTCP socket is fully established, so we don't have to cope with slow MPJ handshake blocking the next subflow creation. Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-01-07mptcp: keep track of local endpoint still available for each mskPaolo Abeni
Include into the path manager status a bitmap tracking the list of local endpoints still available - not yet used - for the relevant mptcp socket. Keep such map updated at endpoint creation/deletion time, so that we can easily skip already used endpoint at local address selection time. The endpoint used by the initial subflow is lazyly accounted at subflow creation time: the usage bitmap is be up2date before endpoint selection and we avoid such unneeded task in some relevant scenarios - e.g. busy servers accepting incoming subflows but not creating any additional ones nor annuncing additional addresses. Overall this allows for fair local endpoints usage in case of subflow failure. As a side effect, this patch also enforces that each endpoint is used at most once for each mptcp connection. Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-01-07mptcp: clean-up MPJ option writingPaolo Abeni
Check for all MPJ variant at once, this reduces the number of conditionals traversed on average and will simplify the next patch. No functional change intended. Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-01-07mptcp: fix per socket endpoint accountingPaolo Abeni
Since full-mesh endpoint support, the reception of a single ADD_ADDR option can cause multiple subflows creation. When such option is accepted we increment 'add_addr_accepted' by one. When we received a paired RM_ADDR option, we deleted all the relevant subflows, decrementing 'add_addr_accepted' by one for each of them. We have a similar issue for 'local_addr_used' Fix them moving the pm endpoint accounting outside the subflow traversal. Fixes: 1a0d6136c5f0 ("mptcp: local addresses fullmesh") Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-01-07mptcp: implement support for user-space disconnectPaolo Abeni
Handle explicitly AF_UNSPEC in mptcp_stream_connnect() to allow user-space to disconnect established MPTCP connections Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-01-07mptcp: cleanup accept and pollPaolo Abeni
After the previous patch, msk->subflow will never be deleted during the whole msk lifetime. We don't need anymore to acquire references to it in mptcp_stream_accept() and we can use the listener subflow accept queue to simplify mptcp_poll() for listener socket. Overall this removes a lock pair and 4 more atomic operations per accept(). Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-01-07mptcp: full disconnect implementationPaolo Abeni
The current mptcp_disconnect() implementation lacks several steps, we additionally need to reset the msk socket state and flush the subflow list. Factor out the needed helper to avoid code duplication. Additionally ensure that the initial subflow is disposed only after mptcp_close(), just reset it at disconnect time. Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-01-07mptcp: implement fastclose xmit pathPaolo Abeni
Allow the MPTCP xmit path to add MP_FASTCLOSE suboption on RST egress packets. Additionally reorder related options writing to reduce the number of conditionals required in the fast path. Co-developed-by: Geliang Tang <geliang.tang@suse.com> Signed-off-by: Geliang Tang <geliang.tang@suse.com> Co-developed-by: Matthieu Baerts <matthieu.baerts@tessares.net> Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net> Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-01-07mptcp: keep snd_una updated for fallback socketPaolo Abeni
After shutdown, for fallback MPTCP sockets, we always have write_seq == snd_una+1 The above will foul OUTQ ioctl(). Keep snd_una in sync with write_seq even after shutdown. Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-12-17mptcp: clean up harmless false expressionsJean Sacren
entry->addr.id is u8 with a range from 0 to 255 and MAX_ADDR_ID is 255. We should drop both false expressions of (entry->addr.id > MAX_ADDR_ID). We should also remove the obsolete parentheses in the first if branch. Use U8_MAX for MAX_ADDR_ID and add a comment to show the link to mptcp_addr_info.id as suggested by Mr. Matthieu Baerts. Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net> Signed-off-by: Jean Sacren <sakiwit@gmail.com> Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-12-17mptcp: enforce HoL-blocking estimationPaolo Abeni
The MPTCP packet scheduler has sub-optimal behavior with asymmetric subflows: if the faster subflow-level cwin is closed, the packet scheduler can enqueue "too much" data on a slower subflow. When all the data on the faster subflow is acked, if the mptcp-level cwin is closed, and link utilization becomes suboptimal. The solution is implementing blest-like[1] HoL-blocking estimation, transmitting only on the subflow with the shorter estimated time to flush the queued memory. If such subflows cwin is closed, we wait even if other subflows are available. This is quite simpler than the original blest implementation, as we leverage the pacing rate provided by the TCP socket. To get a more accurate estimation for the subflow linger-time, we maintain a per-subflow weighted average of such info. Additionally drop magic numbers usage in favor of newly defined macros and use more meaningful names for status variable. [1] http://dl.ifip.org/db/conf/networking/networking2016/1570234725.pdf Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/137 Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net> Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-12-16Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski
No conflicts. Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-12-14mptcp: fix deadlock in __mptcp_push_pending()Maxim Galaganov
__mptcp_push_pending() may call mptcp_flush_join_list() with subflow socket lock held. If such call hits mptcp_sockopt_sync_all() then subsequently __mptcp_sockopt_sync() could try to lock the subflow socket for itself, causing a deadlock. sysrq: Show Blocked State task:ss-server state:D stack: 0 pid: 938 ppid: 1 flags:0x00000000 Call Trace: <TASK> __schedule+0x2d6/0x10c0 ? __mod_memcg_state+0x4d/0x70 ? csum_partial+0xd/0x20 ? _raw_spin_lock_irqsave+0x26/0x50 schedule+0x4e/0xc0 __lock_sock+0x69/0x90 ? do_wait_intr_irq+0xa0/0xa0 __lock_sock_fast+0x35/0x50 mptcp_sockopt_sync_all+0x38/0xc0 __mptcp_push_pending+0x105/0x200 mptcp_sendmsg+0x466/0x490 sock_sendmsg+0x57/0x60 __sys_sendto+0xf0/0x160 ? do_wait_intr_irq+0xa0/0xa0 ? fpregs_restore_userregs+0x12/0xd0 __x64_sys_sendto+0x20/0x30 do_syscall_64+0x38/0x90 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f9ba546c2d0 RSP: 002b:00007ffdc3b762d8 EFLAGS: 00000246 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 00007f9ba56c8060 RCX: 00007f9ba546c2d0 RDX: 000000000000077a RSI: 0000000000e5e180 RDI: 0000000000000234 RBP: 0000000000cc57f0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f9ba56c8060 R13: 0000000000b6ba60 R14: 0000000000cc7840 R15: 41d8685b1d7901b8 </TASK> Fix the issue by using __mptcp_flush_join_list() instead of plain mptcp_flush_join_list() inside __mptcp_push_pending(), as suggested by Florian. The sockopt sync will be deferred to the workqueue. Fixes: 1b3e7ede1365 ("mptcp: setsockopt: handle SO_KEEPALIVE and SO_PRIORITY") Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/244 Suggested-by: Florian Westphal <fw@strlen.de> Reviewed-by: Florian Westphal <fw@strlen.de> Signed-off-by: Maxim Galaganov <max@internet.ru> Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-12-14mptcp: clear 'kern' flag from fallback socketsFlorian Westphal
The mptcp ULP extension relies on sk->sk_sock_kern being set correctly: It prevents setsockopt(fd, IPPROTO_TCP, TCP_ULP, "mptcp", 6); from working for plain tcp sockets (any userspace-exposed socket). But in case of fallback, accept() can return a plain tcp sk. In such case, sk is still tagged as 'kernel' and setsockopt will work. This will crash the kernel, The subflow extension has a NULL ctx->conn mptcp socket: BUG: KASAN: null-ptr-deref in subflow_data_ready+0x181/0x2b0 Call Trace: tcp_data_ready+0xf8/0x370 [..] Fixes: cf7da0d66cc1 ("mptcp: Create SUBFLOW socket for incoming connections") Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-12-14mptcp: remove tcp ulp setsockopt supportFlorian Westphal
TCP_ULP setsockopt cannot be used for mptcp because its already used internally to plumb subflow (tcp) sockets to the mptcp layer. syzbot managed to trigger a crash for mptcp connections that are in fallback mode: KASAN: null-ptr-deref in range [0x0000000000000020-0x0000000000000027] CPU: 1 PID: 1083 Comm: syz-executor.3 Not tainted 5.16.0-rc2-syzkaller #0 RIP: 0010:tls_build_proto net/tls/tls_main.c:776 [inline] [..] __tcp_set_ulp net/ipv4/tcp_ulp.c:139 [inline] tcp_set_ulp+0x428/0x4c0 net/ipv4/tcp_ulp.c:160 do_tcp_setsockopt+0x455/0x37c0 net/ipv4/tcp.c:3391 mptcp_setsockopt+0x1b47/0x2400 net/mptcp/sockopt.c:638 Remove support for TCP_ULP setsockopt. Fixes: d9e4c1291810 ("mptcp: only admit explicitly supported sockopt") Reported-by: syzbot+1fd9b69cde42967d1add@syzkaller.appspotmail.com Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-12-14mptcp: adjust to use netns refcount trackerEric Dumazet
MPTCP can change sk_net_refcnt after sock_create_kern() call. We need to change its corresponding get_net() to avoid a splat at release time, as in : refcount_t: decrement hit 0; leaking memory. WARNING: CPU: 0 PID: 3599 at lib/refcount.c:31 refcount_warn_saturate+0xbf/0x1e0 lib/refcount.c:31 Modules linked in: CPU: 1 PID: 3599 Comm: syz-fuzzer Not tainted 5.16.0-rc4-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:refcount_warn_saturate+0xbf/0x1e0 lib/refcount.c:31 Code: 1d b1 99 a1 09 31 ff 89 de e8 5d 3a 9c fd 84 db 75 e0 e8 74 36 9c fd 48 c7 c7 60 00 05 8a c6 05 91 99 a1 09 01 e8 cc 4b 27 05 <0f> 0b eb c4 e8 58 36 9c fd 0f b6 1d 80 99 a1 09 31 ff 89 de e8 28 RSP: 0018:ffffc90001f5fab0 EFLAGS: 00010286 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000 RDX: ffff888021873a00 RSI: ffffffff815f1e28 RDI: fffff520003ebf48 RBP: 0000000000000004 R08: 0000000000000000 R09: 0000000000000000 R10: ffffffff815ebbce R11: 0000000000000000 R12: 1ffff920003ebf5b R13: 00000000ffffffef R14: ffffffff8d2fcd94 R15: ffffc90001f5fd10 FS: 000000c00008a090(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f0a5b59e300 CR3: 000000001cbe6000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> __refcount_dec include/linux/refcount.h:344 [inline] refcount_dec include/linux/refcount.h:359 [inline] ref_tracker_free+0x4fe/0x610 lib/ref_tracker.c:101 netns_tracker_free include/net/net_namespace.h:327 [inline] put_net_track include/net/net_namespace.h:341 [inline] __sk_destruct+0x4a6/0x920 net/core/sock.c:2042 sk_destruct+0xbd/0xe0 net/core/sock.c:2058 __sk_free+0xef/0x3d0 net/core/sock.c:2069 sk_free+0x78/0xa0 net/core/sock.c:2080 sock_put include/net/sock.h:1911 [inline] __mptcp_close_ssk+0x435/0x590 net/mptcp/protocol.c:2276 __mptcp_destroy_sock+0x35f/0x830 net/mptcp/protocol.c:2702 mptcp_close+0x5f8/0x7f0 net/mptcp/protocol.c:2750 inet_release+0x12e/0x280 net/ipv4/af_inet.c:428 inet6_release+0x4c/0x70 net/ipv6/af_inet6.c:476 __sock_release+0xcd/0x280 net/socket.c:649 sock_close+0x18/0x20 net/socket.c:1314 __fput+0x286/0x9f0 fs/file_table.c:280 task_work_run+0xdd/0x1a0 kernel/task_work.c:164 tracehook_notify_resume include/linux/tracehook.h:189 [inline] exit_to_user_mode_loop kernel/entry/common.c:175 [inline] exit_to_user_mode_prepare+0x27e/0x290 kernel/entry/common.c:207 __syscall_exit_to_user_mode_work kernel/entry/common.c:289 [inline] syscall_exit_to_user_mode+0x19/0x60 kernel/entry/common.c:300 do_syscall_64+0x42/0xb0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x44/0xae Fixes: ffa84b5ffb37 ("net: add netns refcount tracker to struct sock") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: syzbot <syzkaller@googlegroups.com> Cc: Mat Martineau <mathew.j.martineau@linux.intel.com> Cc: Florian Westphal <fw@strlen.de> Acked-by: Paolo Abeni <pabeni@redhat.com> Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net> Link: https://lore.kernel.org/r/20211214043208.3543046-1-eric.dumazet@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-12-13mptcp: never allow the PM to close a listener subflowPaolo Abeni
Currently, when deleting an endpoint the netlink PM treverses all the local MPTCP sockets, regardless of their status. If an MPTCP listener socket is bound to the IP matching the delete endpoint, the listener TCP socket will be closed. That is unexpected, the PM should only affect data subflows. Additionally, syzbot was able to trigger a NULL ptr dereference due to the above: general protection fault, probably for non-canonical address 0xdffffc0000000003: 0000 [#1] PREEMPT SMP KASAN KASAN: null-ptr-deref in range [0x0000000000000018-0x000000000000001f] CPU: 1 PID: 6550 Comm: syz-executor122 Not tainted 5.16.0-rc4-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:__lock_acquire+0xd7d/0x54a0 kernel/locking/lockdep.c:4897 Code: 0f 0e 41 be 01 00 00 00 0f 86 c8 00 00 00 89 05 69 cc 0f 0e e9 bd 00 00 00 48 b8 00 00 00 00 00 fc ff df 48 89 da 48 c1 ea 03 <80> 3c 02 00 0f 85 f3 2f 00 00 48 81 3b 20 75 17 8f 0f 84 52 f3 ff RSP: 0018:ffffc90001f2f818 EFLAGS: 00010016 RAX: dffffc0000000000 RBX: 0000000000000018 RCX: 0000000000000000 RDX: 0000000000000003 RSI: 0000000000000000 RDI: 0000000000000001 RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000001 R10: 0000000000000000 R11: 000000000000000a R12: 0000000000000000 R13: ffff88801b98d700 R14: 0000000000000000 R15: 0000000000000001 FS: 00007f177cd3d700(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f177cd1b268 CR3: 000000001dd55000 CR4: 0000000000350ee0 Call Trace: <TASK> lock_acquire kernel/locking/lockdep.c:5637 [inline] lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5602 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x39/0x50 kernel/locking/spinlock.c:162 finish_wait+0xc0/0x270 kernel/sched/wait.c:400 inet_csk_wait_for_connect net/ipv4/inet_connection_sock.c:464 [inline] inet_csk_accept+0x7de/0x9d0 net/ipv4/inet_connection_sock.c:497 mptcp_accept+0xe5/0x500 net/mptcp/protocol.c:2865 inet_accept+0xe4/0x7b0 net/ipv4/af_inet.c:739 mptcp_stream_accept+0x2e7/0x10e0 net/mptcp/protocol.c:3345 do_accept+0x382/0x510 net/socket.c:1773 __sys_accept4_file+0x7e/0xe0 net/socket.c:1816 __sys_accept4+0xb0/0x100 net/socket.c:1846 __do_sys_accept net/socket.c:1864 [inline] __se_sys_accept net/socket.c:1861 [inline] __x64_sys_accept+0x71/0xb0 net/socket.c:1861 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f177cd8b8e9 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 b1 14 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f177cd3d308 EFLAGS: 00000246 ORIG_RAX: 000000000000002b RAX: ffffffffffffffda RBX: 00007f177ce13408 RCX: 00007f177cd8b8e9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000003 RBP: 00007f177ce13400 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f177ce1340c R13: 00007f177cde1004 R14: 6d705f706374706d R15: 0000000000022000 </TASK> Fix the issue explicitly skipping MPTCP socket in TCP_LISTEN status. Reported-and-tested-by: syzbot+e4d843bb96a9431e6331@syzkaller.appspotmail.com Reviewed-by: Mat Martineau <mathew.j.martineau@linux.intel.com> Fixes: 740d798e8767 ("mptcp: remove id 0 address") Signed-off-by: Paolo Abeni <pabeni@redhat.com> Link: https://lore.kernel.org/r/ebc7594cdd420d241fb2172ddb8542ba64717657.1639238695.git.pabeni@redhat.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-12-07mptcp: support TCP_CORK and TCP_NODELAYMaxim Galaganov
First, add cork and nodelay fields to the mptcp_sock structure so they can be used in sync_socket_options(), and fill them on setsockopt while holding the msk socket lock. Then, on setsockopt set proper tcp_sk(ssk)->nonagle values for subflows by calling __tcp_sock_set_cork() or __tcp_sock_set_nodelay() on the ssk while holding the ssk socket lock. tcp_push_pending_frames() will be invoked on the ssk if a cork was cleared or nodelay was set. Also set MPTCP_PUSH_PENDING bit by calling mptcp_check_and_set_pending(). This will lead to __mptcp_push_pending() being called inside mptcp_release_cb() with new tcp_sk(ssk)->nonagle. Also add getsockopt support for TCP_CORK and TCP_NODELAY. Acked-by: Paolo Abeni <pabeni@redhat.com> Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net> Signed-off-by: Maxim Galaganov <max@internet.ru> Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-12-07mptcp: expose mptcp_check_and_set_pendingMaxim Galaganov
Expose the mptcp_check_and_set_pending() function for use inside MPTCP sockopt code. The next patch will call it when TCP_CORK is cleared or TCP_NODELAY is set on the MPTCP socket in order to push pending data from mptcp_release_cb(). Acked-by: Paolo Abeni <pabeni@redhat.com> Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net> Signed-off-by: Maxim Galaganov <max@internet.ru> Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-12-07mptcp: getsockopt: add support for IP_TOSFlorian Westphal
earlier patch added IP_TOS setsockopt support, this allows to get the value set by earlier setsockopt. Extends mptcp_put_int_option to handle u8 input/output by adding required cast. Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net> Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-12-07mptcp: allow changing the "backup" bit by endpoint idDavide Caratti
a non-zero 'id' is sufficient to identify MPTCP endpoints: allow changing the value of 'backup' bit by simply specifying the endpoint id. Link: https://github.com/multipath-tcp/mptcp_net-next/issues/158 Signed-off-by: Davide Caratti <dcaratti@redhat.com> Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-12-07mptcp: add SIOCINQ, OUTQ and OUTQNSD ioctlsFlorian Westphal
Allows to query in-sequence data ready for read(), total bytes in write queue and total bytes in write queue that have not yet been sent. v2: remove unneeded READ_ONCE() (Paolo Abeni) v3: check for new data unconditionally in SIOCINQ ioctl (Mat Martineau) Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-12-07mptcp: add TCP_INQ cmsg supportFlorian Westphal
Support the TCP_INQ setsockopt. This is a boolean that tells recvmsg path to include the remaining in-sequence bytes in the cmsg data. v2: do not use CB(skb)->offset, increment map_seq instead (Paolo Abeni) v3: adjust CB(skb)->map_seq when taking skb from ofo queue (Paolo Abeni) Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/224 Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-11-26Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski
drivers/net/ipa/ipa_main.c 8afc7e471ad3 ("net: ipa: separate disabling setup from modem stop") 76b5fbcd6b47 ("net: ipa: kill ipa_modem_init()") Duplicated include, drop one. Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-11-20mptcp: use delegate action to schedule 3rd ack retransPaolo Abeni
Scheduling a delack in mptcp_established_options_mp() is not a good idea: such function is called by tcp_send_ack() and the pending delayed ack will be cleared shortly after by the tcp_event_ack_sent() call in __tcp_transmit_skb(). Instead use the mptcp delegated action infrastructure to schedule the delayed ack after the current bh processing completes. Additionally moves the schedule_3rdack_retransmission() helper into protocol.c to avoid making it visible in a different compilation unit. Fixes: ec3edaa7ca6ce02f ("mptcp: Add handling of outgoing MP_JOIN requests") Reviewed-by: Mat Martineau <mathew.j.martineau>@linux.intel.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-11-20mptcp: fix delack timerEric Dumazet
To compute the rtx timeout schedule_3rdack_retransmission() does multiple things in the wrong way: srtt_us is measured in usec/8 and the timeout itself is an absolute value. Fixes: ec3edaa7ca6ce02f ("mptcp: Add handling of outgoing MP_JOIN requests") Acked-by: Paolo Abeni <pabeni@redhat.com> Reviewed-by: Mat Martineau <mathew.j.martineau>@linux.intel.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-11-20mptcp: sockopt: add SOL_IP freebind & transparent optionsFlorian Westphal
These options also need to be set before bind, so do the sync of msk to new ssk socket a bit earlier. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-11-20mptcp: Support for IP_TOS for MPTCP setsockopt()Poorva Sonparote
SOL_IP provides a way to configure network layer attributes in a socket. This patch adds support for IP_TOS for setsockopt(.. ,SOL_IP, ..) Support for SOL_IP is added in mptcp_setsockopt() and IP_TOS is handled in a private function. The idea here is to take in the value passed for IP_TOS and set it to the current subflow, open subflows as well new subflows that might be created after the initial call to setsockopt(). This sync is done using sync_socket_options(.., ssk) and setting the value of tos using __ip_sock_set_tos(ssk,..). The patch has been tested using the packetdrill script here - https://github.com/multipath-tcp/mptcp_net-next/issues/220#issuecomment-947863717 Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/220 Signed-off-by: Poorva Sonparote <psonparo@redhat.com> Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-11-16net: make sock_inuse_add() availableEric Dumazet
MPTCP hard codes it, let us instead provide this helper. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-11-16net: cache align tcp_memory_allocated, tcp_sockets_allocatedEric Dumazet
tcp_memory_allocated and tcp_sockets_allocated often share a common cache line, source of false sharing. Also take care of udp_memory_allocated and mptcp_sockets_allocated. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-28Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski
include/net/sock.h 7b50ecfcc6cd ("net: Rename ->stream_memory_read to ->sock_is_readable") 4c1e34c0dbff ("vsock: Enable y2038 safe timeval for timeout") drivers/net/ethernet/marvell/octeontx2/af/rvu_debugfs.c 0daa55d033b0 ("octeontx2-af: cn10k: debugfs for dumping LMTST map table") e77bcdd1f639 ("octeontx2-af: Display all enabled PF VF rsrc_alloc entries.") Adjacent code addition in both cases, keep both. Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-10-28mptcp: fix corrupt receiver key in MPC + data + checksumDavide Caratti
using packetdrill it's possible to observe that the receiver key contains random values when clients transmit MP_CAPABLE with data and checksum (as specified in RFC8684 ยง3.1). Fix the layout of mptcp_out_options, to avoid using the skb extension copy when writing the MP_CAPABLE sub-option. Fixes: d7b269083786 ("mptcp: shrink mptcp_out_options struct") Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/233 Reported-by: Poorva Sonparote <psonparo@redhat.com> Signed-off-by: Davide Caratti <dcaratti@redhat.com> Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com> Link: https://lore.kernel.org/r/20211027203855.264600-1-mathew.j.martineau@linux.intel.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-10-28tcp: factorize ip_summed settingEric Dumazet
Setting skb->ip_summed to CHECKSUM_PARTIAL can be centralized in tcp_stream_alloc_skb() and __mptcp_do_alloc_tx_skb() instead of being done multiple times. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-28tcp: no longer set skb->reserved_tailroomEric Dumazet
TCP/MPTCP sendmsg() no longer puts payload in skb->head, we can remove not needed code. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-28tcp: cleanup tcp_remove_empty_skb() useEric Dumazet
All tcp_remove_empty_skb() callers now use tcp_write_queue_tail() for the skb argument, we can therefore factorize code. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-27mptcp: drop unused sk in mptcp_push_releaseGeliang Tang
Since mptcp_set_timeout() had removed from mptcp_push_release() in commit 33d41c9cd74c5 ("mptcp: more accurate timeout"), the argument sk in mptcp_push_release() became useless. Let's drop it. Fixes: 33d41c9cd74c5 ("mptcp: more accurate timeout") Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net> Signed-off-by: Geliang Tang <geliang.tang@suse.com> Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-10-27mptcp: allocate fwd memory separately on the rx and tx pathPaolo Abeni
All the mptcp receive path is protected by the msk socket spinlock. As consequences, the tx path has to play a few tricks to allocate the forward memory without acquiring the spinlock multiple times, making the overall TX path quite complex. This patch tries to clean-up a bit the tx path, using completely separated fwd memory allocation, for the rx and the tx path. The forward memory allocated in the rx path is now accounted in msk->rmem_fwd_alloc and is (still) protected by the msk socket spinlock. To cope with the above we provide a few MPTCP-specific variants for the helpers to charge, uncharge, reclaim and free the forward memory in the receive path. msk->sk_forward_alloc now accounts only the forward memory for the tx path, we can use the plain core sock helper to manipulate it and drop quite a bit of complexity. On memory pressure, both rx and tx fwd memories are reclaimed. Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-10-16mptcp: Make mptcp_pm_nl_mp_prio_send_ack() staticMat Martineau
This function is only used within pm_netlink.c now. Fixes: 067065422fcd ("mptcp: add the outgoing MP_PRIO support") Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net> Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-16mptcp: increase default max additional subflows to 2Paolo Abeni
The current default does not allowing additional subflows, mostly as a safety restriction to avoid uncontrolled resource consumption on busy servers. Still the system admin and/or the application have to opt-in to MPTCP explicitly. After that, they need to change (increase) the default maximum number of additional subflows. Let set that to reasonable default, and make end-users life easier. Additionally we need to update some self-tests accordingly. Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-16mptcp: Avoid NULL dereference in mptcp_getsockopt_subflow_addrs()Tim Gardner
Coverity complains of a possible NULL dereference in mptcp_getsockopt_subflow_addrs(): 861 } else if (sk->sk_family == AF_INET6) { 3. returned_null: inet6_sk returns NULL. [show details] 4. var_assigned: Assigning: np = NULL return value from inet6_sk. 862 const struct ipv6_pinfo *np = inet6_sk(sk); Fix this by checking for NULL. Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/231 Fixes: c11c5906bc0a ("mptcp: add MPTCP_SUBFLOW_ADDRS getsockopt support") Cc: Florian Westphal <fw@strlen.de> Signed-off-by: Tim Gardner <tim.gardner@canonical.com> [mjm: Added WARN_ON_ONCE() to the unexpected case] Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-14Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski
tools/testing/selftests/net/ioam6.sh 7b1700e009cc ("selftests: net: modify IOAM tests for undef bits") bf77b1400a56 ("selftests: net: Test for the IOAM encapsulation with IPv6") Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-10-08mptcp: fix possible stall on recvmsg()Paolo Abeni
recvmsg() can enter an infinite loop if the caller provides the MSG_WAITALL, the data present in the receive queue is not sufficient to fulfill the request, and no more data is received by the peer. When the above happens, mptcp_wait_data() will always return with no wait, as the MPTCP_DATA_READY flag checked by such function is set and never cleared in such code path. Leveraging the above syzbot was able to trigger an RCU stall: rcu: INFO: rcu_preempt self-detected stall on CPU rcu: 0-...!: (10499 ticks this GP) idle=0af/1/0x4000000000000000 softirq=10678/10678 fqs=1 (t=10500 jiffies g=13089 q=109) rcu: rcu_preempt kthread starved for 10497 jiffies! g13089 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=1 rcu: Unless rcu_preempt kthread gets sufficient CPU time, OOM is now expected behavior. rcu: RCU grace-period kthread stack dump: task:rcu_preempt state:R running task stack:28696 pid: 14 ppid: 2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:4955 [inline] __schedule+0x940/0x26f0 kernel/sched/core.c:6236 schedule+0xd3/0x270 kernel/sched/core.c:6315 schedule_timeout+0x14a/0x2a0 kernel/time/timer.c:1881 rcu_gp_fqs_loop+0x186/0x810 kernel/rcu/tree.c:1955 rcu_gp_kthread+0x1de/0x320 kernel/rcu/tree.c:2128 kthread+0x405/0x4f0 kernel/kthread.c:327 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 rcu: Stack dump where RCU GP kthread last ran: Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 8510 Comm: syz-executor827 Not tainted 5.15.0-rc2-next-20210920-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:bytes_is_nonzero mm/kasan/generic.c:84 [inline] RIP: 0010:memory_is_nonzero mm/kasan/generic.c:102 [inline] RIP: 0010:memory_is_poisoned_n mm/kasan/generic.c:128 [inline] RIP: 0010:memory_is_poisoned mm/kasan/generic.c:159 [inline] RIP: 0010:check_region_inline mm/kasan/generic.c:180 [inline] RIP: 0010:kasan_check_range+0xc8/0x180 mm/kasan/generic.c:189 Code: 38 00 74 ed 48 8d 50 08 eb 09 48 83 c0 01 48 39 d0 74 7a 80 38 00 74 f2 48 89 c2 b8 01 00 00 00 48 85 d2 75 56 5b 5d 41 5c c3 <48> 85 d2 74 5e 48 01 ea eb 09 48 83 c0 01 48 39 d0 74 50 80 38 00 RSP: 0018:ffffc9000cd676c8 EFLAGS: 00000283 RAX: ffffed100e9a110e RBX: ffffed100e9a110f RCX: ffffffff88ea062a RDX: 0000000000000001 RSI: 0000000000000008 RDI: ffff888074d08870 RBP: ffffed100e9a110e R08: 0000000000000001 R09: ffff888074d08877 R10: ffffed100e9a110e R11: 0000000000000000 R12: ffff888074d08000 R13: ffff888074d08000 R14: ffff888074d08088 R15: ffff888074d08000 FS: 0000555556d8e300(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000 S: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000020000180 CR3: 0000000068909000 CR4: 00000000001506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: instrument_atomic_read_write include/linux/instrumented.h:101 [inline] test_and_clear_bit include/asm-generic/bitops/instrumented-atomic.h:83 [inline] mptcp_release_cb+0x14a/0x210 net/mptcp/protocol.c:3016 release_sock+0xb4/0x1b0 net/core/sock.c:3204 mptcp_wait_data net/mptcp/protocol.c:1770 [inline] mptcp_recvmsg+0xfd1/0x27b0 net/mptcp/protocol.c:2080 inet6_recvmsg+0x11b/0x5e0 net/ipv6/af_inet6.c:659 sock_recvmsg_nosec net/socket.c:944 [inline] ____sys_recvmsg+0x527/0x600 net/socket.c:2626 ___sys_recvmsg+0x127/0x200 net/socket.c:2670 do_recvmmsg+0x24d/0x6d0 net/socket.c:2764 __sys_recvmmsg net/socket.c:2843 [inline] __do_sys_recvmmsg net/socket.c:2866 [inline] __se_sys_recvmmsg net/socket.c:2859 [inline] __x64_sys_recvmmsg+0x20b/0x260 net/socket.c:2859 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7fc200d2dc39 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 41 15 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 c0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007ffc5758e5a8 EFLAGS: 00000246 ORIG_RAX: 000000000000012b RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00007fc200d2dc39 RDX: 0000000000000002 RSI: 00000000200017c0 RDI: 0000000000000003 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000f0b5ff R10: 0000000000000100 R11: 0000000000000246 R12: 0000000000000003 R13: 00007ffc5758e5d0 R14: 00007ffc5758e5c0 R15: 0000000000000003 Fix the issue by replacing the MPTCP_DATA_READY bit with direct inspection of the msk receive queue. Reported-and-tested-by: syzbot+3360da629681aa0d22fe@syzkaller.appspotmail.com Fixes: 7a6a6cbc3e59 ("mptcp: recvmsg() can drain data from multiple subflow") Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-09-30Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski
drivers/net/phy/bcm7xxx.c d88fd1b546ff ("net: phy: bcm7xxx: Fixed indirect MMD operations") f68d08c437f9 ("net: phy: bcm7xxx: Add EPHY entry for 72165") net/sched/sch_api.c b193e15ac69d ("net: prevent user from passing illegal stab size") 69508d43334e ("net_sched: Use struct_size() and flex_array_size() helpers") Both cases trivial - adjacent code additions. Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-09-30mptcp: use batch snmp operations in mptcp_seq_show()Eric Dumazet
Using snmp_get_cpu_field_batch() allows for better cpu cache utilization, especially on hosts with large number of cpus. Also remove special handling when mptcp mibs where not yet allocated. I chose to use temporary storage on the stack to keep this patch simple. We might in the future use the storage allocated in netstat_seq_show(). Combined with prior patch (inlining snmp_get_cpu_field) time to fetch and output mptcp counters on a 256 cpu host [1] goes from 75 usec to 16 usec. [1] L1 cache size is 32KB, it is not big enough to hold all dataset. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-09-30net: introduce and use lock_sock_fast_nested()Paolo Abeni
Syzkaller reported a false positive deadlock involving the nl socket lock and the subflow socket lock: MPTCP: kernel_bind error, err=-98 ============================================ WARNING: possible recursive locking detected 5.15.0-rc1-syzkaller #0 Not tainted -------------------------------------------- syz-executor998/6520 is trying to acquire lock: ffff8880795718a0 (k-sk_lock-AF_INET){+.+.}-{0:0}, at: mptcp_close+0x267/0x7b0 net/mptcp/protocol.c:2738 but task is already holding lock: ffff8880787c8c60 (k-sk_lock-AF_INET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1612 [inline] ffff8880787c8c60 (k-sk_lock-AF_INET){+.+.}-{0:0}, at: mptcp_close+0x23/0x7b0 net/mptcp/protocol.c:2720 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(k-sk_lock-AF_INET); lock(k-sk_lock-AF_INET); *** DEADLOCK *** May be due to missing lock nesting notation 3 locks held by syz-executor998/6520: #0: ffffffff8d176c50 (cb_lock){++++}-{3:3}, at: genl_rcv+0x15/0x40 net/netlink/genetlink.c:802 #1: ffffffff8d176d08 (genl_mutex){+.+.}-{3:3}, at: genl_lock net/netlink/genetlink.c:33 [inline] #1: ffffffff8d176d08 (genl_mutex){+.+.}-{3:3}, at: genl_rcv_msg+0x3e0/0x580 net/netlink/genetlink.c:790 #2: ffff8880787c8c60 (k-sk_lock-AF_INET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1612 [inline] #2: ffff8880787c8c60 (k-sk_lock-AF_INET){+.+.}-{0:0}, at: mptcp_close+0x23/0x7b0 net/mptcp/protocol.c:2720 stack backtrace: CPU: 1 PID: 6520 Comm: syz-executor998 Not tainted 5.15.0-rc1-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 print_deadlock_bug kernel/locking/lockdep.c:2944 [inline] check_deadlock kernel/locking/lockdep.c:2987 [inline] validate_chain kernel/locking/lockdep.c:3776 [inline] __lock_acquire.cold+0x149/0x3ab kernel/locking/lockdep.c:5015 lock_acquire kernel/locking/lockdep.c:5625 [inline] lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5590 lock_sock_fast+0x36/0x100 net/core/sock.c:3229 mptcp_close+0x267/0x7b0 net/mptcp/protocol.c:2738 inet_release+0x12e/0x280 net/ipv4/af_inet.c:431 __sock_release net/socket.c:649 [inline] sock_release+0x87/0x1b0 net/socket.c:677 mptcp_pm_nl_create_listen_socket+0x238/0x2c0 net/mptcp/pm_netlink.c:900 mptcp_nl_cmd_add_addr+0x359/0x930 net/mptcp/pm_netlink.c:1170 genl_family_rcv_msg_doit+0x228/0x320 net/netlink/genetlink.c:731 genl_family_rcv_msg net/netlink/genetlink.c:775 [inline] genl_rcv_msg+0x328/0x580 net/netlink/genetlink.c:792 netlink_rcv_skb+0x153/0x420 net/netlink/af_netlink.c:2504 genl_rcv+0x24/0x40 net/netlink/genetlink.c:803 netlink_unicast_kernel net/netlink/af_netlink.c:1314 [inline] netlink_unicast+0x533/0x7d0 net/netlink/af_netlink.c:1340 netlink_sendmsg+0x86d/0xdb0 net/netlink/af_netlink.c:1929 sock_sendmsg_nosec net/socket.c:704 [inline] sock_sendmsg+0xcf/0x120 net/socket.c:724 sock_no_sendpage+0x101/0x150 net/core/sock.c:2980 kernel_sendpage.part.0+0x1a0/0x340 net/socket.c:3504 kernel_sendpage net/socket.c:3501 [inline] sock_sendpage+0xe5/0x140 net/socket.c:1003 pipe_to_sendpage+0x2ad/0x380 fs/splice.c:364 splice_from_pipe_feed fs/splice.c:418 [inline] __splice_from_pipe+0x43e/0x8a0 fs/splice.c:562 splice_from_pipe fs/splice.c:597 [inline] generic_splice_sendpage+0xd4/0x140 fs/splice.c:746 do_splice_from fs/splice.c:767 [inline] direct_splice_actor+0x110/0x180 fs/splice.c:936 splice_direct_to_actor+0x34b/0x8c0 fs/splice.c:891 do_splice_direct+0x1b3/0x280 fs/splice.c:979 do_sendfile+0xae9/0x1240 fs/read_write.c:1249 __do_sys_sendfile64 fs/read_write.c:1314 [inline] __se_sys_sendfile64 fs/read_write.c:1300 [inline] __x64_sys_sendfile64+0x1cc/0x210 fs/read_write.c:1300 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f215cb69969 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 14 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 c0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007ffc96bb3868 EFLAGS: 00000246 ORIG_RAX: 0000000000000028 RAX: ffffffffffffffda RBX: 00007f215cbad072 RCX: 00007f215cb69969 RDX: 0000000000000000 RSI: 0000000000000004 RDI: 0000000000000005 RBP: 0000000000000000 R08: 00007ffc96bb3a08 R09: 00007ffc96bb3a08 R10: 0000000100000002 R11: 0000000000000246 R12: 00007ffc96bb387c R13: 431bde82d7b634db R14: 0000000000000000 R15: 0000000000000000 the problem originates from uncorrect lock annotation in the mptcp code and is only visible since commit 2dcb96bacce3 ("net: core: Correct the sock::sk_lock.owned lockdep annotations"), but is present since the port-based endpoint support initial implementation. This patch addresses the issue introducing a nested variant of lock_sock_fast() and using it in the relevant code path. Fixes: 1729cf186d8a ("mptcp: create the listening socket for new port") Fixes: 2dcb96bacce3 ("net: core: Correct the sock::sk_lock.owned lockdep annotations") Suggested-by: Thomas Gleixner <tglx@linutronix.de> Reported-and-tested-by: syzbot+1dd53f7a89b299d59eaf@syzkaller.appspotmail.com Signed-off-by: Paolo Abeni <pabeni@redhat.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-09-25mptcp: re-arm retransmit timer if data is pendingFlorian Westphal
The retransmit head will be NULL in case there is no in-flight data (meaning all data injected into network has been acked). In that case the retransmit timer is stopped. This is only correct if there is no more pending, not-yet-sent data. If there is, the retransmit timer needs to set the PENDING bit again so that mptcp tries to send the remaining (new) data once a subflow can accept more data. Also, mptcp_subflow_get_retrans() has to be called unconditionally. This function checks for subflows that have become unresponsive and marks them as stale, so in the case where the rtx queue is empty, subflows will never be marked stale which prevents available backup subflows from becoming eligible for transmit. Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/226 Acked-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-09-25mptcp: remove tx_pending_dataFlorian Westphal
The update on recovery is not correct. msk->tx_pending_data += msk->snd_nxt - rtx_head->data_seq; will update tx_pending_data multiple times when a subflow is declared stale while earlier recovery is still in progress. This means that tx_pending_data will still be positive even after all data as has been transmitted. Rather than fix it, remove this field: there are no consumers. The outstanding data byte count can be computed either via "msk->write_seq - rtx_head->data_seq" or "msk->write_seq - msk->snd_una". The latter is more recent/accurate estimate as rtx_head adjustment is deferred until mptcp lock can be acquired. Acked-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-09-25mptcp: use lockdep_assert_held_once() instead of open-coding itPaolo Abeni
We have a few more places where the mptcp code duplicates lockdep_assert_held_once(). Let's use the existing macro and avoid a bunch of compiler's conditional. Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net> Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-09-25mptcp: use OPTIONS_MPTCP_MPCGeliang Tang
Since OPTIONS_MPTCP_MPC has been defined, use it instead of open-coding. Acked-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: Geliang Tang <geliangtang@xiaomi.com> Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-09-25mptcp: do not shrink snd_nxt when recoveringFlorian Westphal
When recovering after a link failure, snd_nxt should not be set to a lower value. Else, update of snd_nxt is broken because: msk->snd_nxt += ret; (where ret is number of bytes sent) assumes that snd_nxt always moves forward. After reduction, its possible that snd_nxt update gets out of sync: dfrag we just sent might have had a data sequence number even past recovery_snd_nxt. This change factors the common msk state update to a helper and updates snd_nxt based on the current dfrag data sequence number. The conditional is required for the recovery phase where we may re-transmit old dfrags that are before current snd_nxt. After this change, snd_nxt only moves forward and covers all in-sequence data that was transmitted. recovery_snd_nxt is retained to detect when recovery has completed. Fixes: 1e1d9d6f119c5 ("mptcp: handle pending data on closed subflow") Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>