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2023-08-22mptcp: use get_send wrapperGeliang Tang
This patch adds the multiple subflows support for __mptcp_push_pending and __mptcp_subflow_push_pending. Use get_send() wrapper instead of mptcp_subflow_get_send() in them. Check the subflow scheduled flags to test which subflow or subflows are picked by the scheduler, use them to send data. Move msk_owned_by_me() and fallback checks into get_send() wrapper from mptcp_subflow_get_send(). This commit allows the scheduler to set the subflow->scheduled bit in multiple subflows, but it does not allow for sending redundant data. Multiple scheduled subflows will send sequential data on each subflow. Reviewed-by: Mat Martineau <martineau@kernel.org> Signed-off-by: Geliang Tang <geliang.tang@suse.com> Signed-off-by: Mat Martineau <martineau@kernel.org> Link: https://lore.kernel.org/r/20230821-upstream-net-next-20230818-v1-8-0c860fb256a8@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-08-22mptcp: add scheduler wrappersGeliang Tang
This patch defines two packet scheduler wrappers mptcp_sched_get_send() and mptcp_sched_get_retrans(), invoke get_subflow() of msk->sched in them. Set data->reinject to true in mptcp_sched_get_retrans(), set it false in mptcp_sched_get_send(). If msk->sched is NULL, use default functions mptcp_subflow_get_send() and mptcp_subflow_get_retrans() to send data. Reviewed-by: Mat Martineau <martineau@kernel.org> Signed-off-by: Geliang Tang <geliang.tang@suse.com> Signed-off-by: Mat Martineau <martineau@kernel.org> Link: https://lore.kernel.org/r/20230821-upstream-net-next-20230818-v1-7-0c860fb256a8@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-08-22mptcp: add sched in mptcp_sockGeliang Tang
This patch adds a new struct member sched in struct mptcp_sock. And two helpers mptcp_init_sched() and mptcp_release_sched() to init and release it. Init it with the sysctl scheduler in mptcp_init_sock(), copy the scheduler from the parent in mptcp_sk_clone(), and release it in __mptcp_destroy_sock(). Acked-by: Paolo Abeni <pabeni@redhat.com> Reviewed-by: Mat Martineau <martineau@kernel.org> Signed-off-by: Geliang Tang <geliang.tang@suse.com> Signed-off-by: Mat Martineau <martineau@kernel.org> Link: https://lore.kernel.org/r/20230821-upstream-net-next-20230818-v1-5-0c860fb256a8@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-08-22mptcp: drop last_snd and MPTCP_RESET_SCHEDULERGeliang Tang
Since the burst check conditions have moved out of the function mptcp_subflow_get_send(), it makes all msk->last_snd useless. This patch drops them as well as the macro MPTCP_RESET_SCHEDULER. Reviewed-by: Mat Martineau <martineau@kernel.org> Signed-off-by: Geliang Tang <geliang.tang@suse.com> Signed-off-by: Mat Martineau <martineau@kernel.org> Link: https://lore.kernel.org/r/20230821-upstream-net-next-20230818-v1-2-0c860fb256a8@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-08-22mptcp: refactor push_pending logicGeliang Tang
To support redundant package schedulers more easily, this patch refactors __mptcp_push_pending() logic from: For each dfrag: While sends succeed: Call the scheduler (selects subflow and msk->snd_burst) Update subflow locks (push/release/acquire as needed) Send the dfrag data with mptcp_sendmsg_frag() Update already_sent, snd_nxt, snd_burst Update msk->first_pending Push/release on final subflow -> While first_pending isn't empty: Call the scheduler (selects subflow and msk->snd_burst) Update subflow locks (push/release/acquire as needed) For each pending dfrag: While sends succeed: Send the dfrag data with mptcp_sendmsg_frag() Update already_sent, snd_nxt, snd_burst Update msk->first_pending Break if required by msk->snd_burst / etc Push/release on final subflow Refactors __mptcp_subflow_push_pending logic from: For each dfrag: While sends succeed: Call the scheduler (selects subflow and msk->snd_burst) Send the dfrag data with mptcp_subflow_delegate(), break Send the dfrag data with mptcp_sendmsg_frag() Update dfrag->already_sent, msk->snd_nxt, msk->snd_burst Update msk->first_pending -> While first_pending isn't empty: Call the scheduler (selects subflow and msk->snd_burst) Send the dfrag data with mptcp_subflow_delegate(), break Send the dfrag data with mptcp_sendmsg_frag() For each pending dfrag: While sends succeed: Send the dfrag data with mptcp_sendmsg_frag() Update already_sent, snd_nxt, snd_burst Update msk->first_pending Break if required by msk->snd_burst / etc Move the duplicate code from __mptcp_push_pending() and __mptcp_subflow_push_pending() into a new helper function, named __subflow_push_pending(). Simplify __mptcp_push_pending() and __mptcp_subflow_push_pending() by invoking this helper. Also move the burst check conditions out of the function mptcp_subflow_get_send(), check them in __subflow_push_pending() in the inner "for each pending dfrag" loop. Reviewed-by: Mat Martineau <martineau@kernel.org> Signed-off-by: Geliang Tang <geliang.tang@suse.com> Signed-off-by: Mat Martineau <martineau@kernel.org> Link: https://lore.kernel.org/r/20230821-upstream-net-next-20230818-v1-1-0c860fb256a8@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-08-16inet: move inet->defer_connect to inet->inet_flagsEric Dumazet
Make room in struct inet_sock by removing this bit field, using one available bit in inet_flags instead. Also move local_port_range to fill the resulting hole, saving 8 bytes on 64bit arches. Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Soheil Hassas Yeganeh <soheil@google.com> Reviewed-by: Simon Horman <horms@kernel.org> Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2023-08-14mptcp: Remove unnecessary test for __mptcp_init_sock()Kuniyuki Iwashima
__mptcp_init_sock() always returns 0 because mptcp_init_sock() used to return the value directly. But after commit 18b683bff89d ("mptcp: queue data for mptcp level retransmission"), __mptcp_init_sock() need not return value anymore. Let's remove the unnecessary test for __mptcp_init_sock() and make it return void. Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net> Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2023-08-14mptcp: get rid of msk->subflowPaolo Abeni
Such field is now unused just as a flag to control the first subflow deletion at close() time. Introduce a new bit flag for that and finally drop the mentioned field. As an intended side effect, now the first subflow sock is not freed before close() even for passive sockets. The msk has no open/active subflows if the first one is closed and the subflow list is singular, update accordingly the state check in mptcp_stream_accept(). Among other benefits, the subflow removal, reduces the amount of memory used on the client side for each mptcp connection, allows passive sockets to go through successful accept()/disconnect()/connect() and makes return error code consistent for failing both passive and active sockets. Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/290 Signed-off-by: Paolo Abeni <pabeni@redhat.com> Reviewed-by: Mat Martineau <martineau@kernel.org> Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2023-08-14mptcp: change the mpc check helper to return a skPaolo Abeni
After the previous patch the __mptcp_nmpc_socket helper is used only to ensure that the MPTCP socket is a suitable status - that is, the mptcp capable handshake is not started yet. Change the return value to the relevant subflow sock, to finally remove the last references to first subflow socket in the MPTCP stack. As a bonus, we can get rid of a few local variables in different functions. No functional change intended. Signed-off-by: Paolo Abeni <pabeni@redhat.com> Reviewed-by: Mat Martineau <martineau@kernel.org> Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2023-08-14mptcp: avoid unneeded indirection in mptcp_stream_accept()Paolo Abeni
We are going to remove the first subflow socket soon, so avoid the additional indirection at accept() time. Instead access directly the first subflow sock, and update mptcp_accept() to operate on it. This allows dropping a duplicated check in mptcp_accept(). No functional changes intended. Signed-off-by: Paolo Abeni <pabeni@redhat.com> Reviewed-by: Mat Martineau <martineau@kernel.org> Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2023-08-14mptcp: avoid additional indirection in mptcp_poll()Paolo Abeni
We are going to remove the first subflow socket soon, so avoid the additional indirection at poll() time. Instead access directly the first subflow sock. No functional changes intended. Signed-off-by: Paolo Abeni <pabeni@redhat.com> Reviewed-by: Mat Martineau <martineau@kernel.org> Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2023-08-14mptcp: avoid additional indirection in mptcp_listen()Paolo Abeni
We are going to remove the first subflow socket soon, so avoid the additional indirection via at listen() time. Instead call directly the recently introduced helper on the first subflow sock. No functional changes intended. Signed-off-by: Paolo Abeni <pabeni@redhat.com> Reviewed-by: Mat Martineau <martineau@kernel.org> Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2023-08-14mptcp: mptcp: avoid additional indirection in mptcp_bind()Paolo Abeni
We are going to remove the first subflow socket soon, so avoid the additional indirection via at bind() time. Instead call directly the recently introduced helpers on the first subflow sock. Signed-off-by: Paolo Abeni <pabeni@redhat.com> Reviewed-by: Mat Martineau <martineau@kernel.org> Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2023-08-14mptcp: avoid subflow socket usage in mptcp_get_port()Paolo Abeni
We are going to remove the first subflow socket soon, so avoid accessing it in mptcp_get_port(). Instead, access directly the first subflow sock. Signed-off-by: Paolo Abeni <pabeni@redhat.com> Reviewed-by: Mat Martineau <martineau@kernel.org> Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2023-08-14mptcp: avoid additional __inet_stream_connect() callPaolo Abeni
The mptcp protocol maintains an additional socket just to easily invoke a few stream operations on the first subflow. One of them is __inet_stream_connect(). We are going to remove the first subflow socket soon, so avoid the additional indirection via at connect time, calling directly into the sock-level connect() ops. The sk-level connect never return -EINPROGRESS, cleanup the error path accordingly. Additionally, the ssk status on error is always TCP_CLOSE. Avoid unneeded access to the subflow sk state. No functional change intended. Signed-off-by: Paolo Abeni <pabeni@redhat.com> Reviewed-by: Mat Martineau <martineau@kernel.org> Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2023-08-14mptcp: avoid unneeded mptcp_token_destroy() callsPaolo Abeni
The MPTCP protocol currently clears the msk token both at connect() and listen() time. That is needed to deal with failing connect() calls that can create a new token while leaving the sk in TCP_CLOSE,SS_UNCONNECTED status and thus allowing later connect() and/or listen() calls. Let's deal with such failures explicitly, cleaning the token in a timely manner and avoid the confusing early mptcp_token_destroy(). Signed-off-by: Paolo Abeni <pabeni@redhat.com> Reviewed-by: Mat Martineau <martineau@kernel.org> Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2023-08-10Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski
Cross-merge networking fixes after downstream PR. No conflicts. Adjacent changes: drivers/net/ethernet/intel/igc/igc_main.c 06b412589eef ("igc: Add lock to safeguard global Qbv variables") d3750076d464 ("igc: Add TransmissionOverrun counter") drivers/net/ethernet/microsoft/mana/mana_en.c a7dfeda6fdec ("net: mana: Fix MANA VF unload when hardware is unresponsive") a9ca9f9ceff3 ("page_pool: split types and declarations from page_pool.h") 92272ec4107e ("eth: add missing xdp.h includes in drivers") net/mptcp/protocol.h 511b90e39250 ("mptcp: fix disconnect vs accept race") b8dc6d6ce931 ("mptcp: fix rcv buffer auto-tuning") tools/testing/selftests/net/mptcp/mptcp_join.sh c8c101ae390a ("selftests: mptcp: join: fix 'implicit EP' test") 03668c65d153 ("selftests: mptcp: join: rework detailed report") Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-08-09net: annotate data-races around sock->opsEric Dumazet
IPV6_ADDRFORM socket option is evil, because it can change sock->ops while other threads might read it. Same issue for sk->sk_family being set to AF_INET. Adding READ_ONCE() over sock->ops reads is needed for sockets that might be impacted by IPV6_ADDRFORM. Note that mptcp_is_tcpsk() can also overwrite sock->ops. Adding annotations for all sk->sk_family reads will require more patches :/ BUG: KCSAN: data-race in ____sys_sendmsg / do_ipv6_setsockopt write to 0xffff888109f24ca0 of 8 bytes by task 4470 on cpu 0: do_ipv6_setsockopt+0x2c5e/0x2ce0 net/ipv6/ipv6_sockglue.c:491 ipv6_setsockopt+0x57/0x130 net/ipv6/ipv6_sockglue.c:1012 udpv6_setsockopt+0x95/0xa0 net/ipv6/udp.c:1690 sock_common_setsockopt+0x61/0x70 net/core/sock.c:3663 __sys_setsockopt+0x1c3/0x230 net/socket.c:2273 __do_sys_setsockopt net/socket.c:2284 [inline] __se_sys_setsockopt net/socket.c:2281 [inline] __x64_sys_setsockopt+0x66/0x80 net/socket.c:2281 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd read to 0xffff888109f24ca0 of 8 bytes by task 4469 on cpu 1: sock_sendmsg_nosec net/socket.c:724 [inline] sock_sendmsg net/socket.c:747 [inline] ____sys_sendmsg+0x349/0x4c0 net/socket.c:2503 ___sys_sendmsg net/socket.c:2557 [inline] __sys_sendmmsg+0x263/0x500 net/socket.c:2643 __do_sys_sendmmsg net/socket.c:2672 [inline] __se_sys_sendmmsg net/socket.c:2669 [inline] __x64_sys_sendmmsg+0x57/0x60 net/socket.c:2669 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd value changed: 0xffffffff850e32b8 -> 0xffffffff850da890 Reported by Kernel Concurrency Sanitizer on: CPU: 1 PID: 4469 Comm: syz-executor.1 Not tainted 6.4.0-rc5-syzkaller-00313-g4c605260bc60 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/25/2023 Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com> Link: https://lore.kernel.org/r/20230808135809.2300241-1-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-08-04mptcp: avoid bogus reset on fallback closePaolo Abeni
Since the blamed commit, the MPTCP protocol unconditionally sends TCP resets on all the subflows on disconnect(). That fits full-blown MPTCP sockets - to implement the fastclose mechanism - but causes unexpected corruption of the data stream, caught as sporadic self-tests failures. Fixes: d21f83485518 ("mptcp: use fastclose on more edge scenarios") Cc: stable@vger.kernel.org Tested-by: Matthieu Baerts <matthieu.baerts@tessares.net> Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/419 Signed-off-by: Paolo Abeni <pabeni@redhat.com> Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net> Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net> Link: https://lore.kernel.org/r/20230803-upstream-net-20230803-misc-fixes-6-5-v1-3-6671b1ab11cc@tessares.net Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-08-04mptcp: fix the incorrect judgment for msk->cb_flagsXiang Yang
Coccicheck reports the error below: net/mptcp/protocol.c:3330:15-28: ERROR: test of a variable/field address Since the address of msk->cb_flags is used in __test_and_clear_bit, the address should not be NULL. The judgment for if (unlikely(msk->cb_flags)) will always be true, we should check the real value of msk->cb_flags here. Fixes: 65a569b03ca8 ("mptcp: optimize release_cb for the common case") Signed-off-by: Xiang Yang <xiangyang3@huawei.com> Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net> Link: https://lore.kernel.org/r/20230803072438.1847500-1-xiangyang3@huawei.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-07-27Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski
Cross-merge networking fixes after downstream PR. No conflicts or adjacent changes. Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-07-26mptcp: more accurate NL event generationPaolo Abeni
Currently the mptcp code generate a "new listener" event even if the actual listen() syscall fails. Address the issue moving the event generation call under the successful branch. Cc: stable@vger.kernel.org Fixes: f8c9dfbd875b ("mptcp: add pm listener events") Reviewed-by: Mat Martineau <martineau@kernel.org> Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: Mat Martineau <martineau@kernel.org> Link: https://lore.kernel.org/r/20230725-send-net-20230725-v1-2-6f60fe7137a9@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-07-24mptcp: fix rcv buffer auto-tuningPaolo Abeni
The MPTCP code uses the assumption that the tcp_win_from_space() helper does not use any TCP-specific field, and thus works correctly operating on an MPTCP socket. The commit dfa2f0483360 ("tcp: get rid of sysctl_tcp_adv_win_scale") broke such assumption, and as a consequence most MPTCP connections stall on zero-window event due to auto-tuning changing the rcv buffer size quite randomly. Address the issue syncing again the MPTCP auto-tuning code with the TCP one. To achieve that, factor out the windows size logic in socket independent helpers, and reuse them in mptcp_rcv_space_adjust(). The MPTCP level scaling_ratio is selected as the minimum one from the all the subflows, as a worst-case estimate. Fixes: dfa2f0483360 ("tcp: get rid of sysctl_tcp_adv_win_scale") Signed-off-by: Paolo Abeni <pabeni@redhat.com> Co-developed-by: Matthieu Baerts <matthieu.baerts@tessares.net> Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net> Reviewed-by: Eric Dumazet <edumazet@google.com> Acked-by: Soheil Hassas Yeganeh <soheil@google.com> Link: https://lore.kernel.org/r/20230720-upstream-net-next-20230720-mptcp-fix-rcv-buffer-auto-tuning-v1-1-175ef12b8380@tessares.net Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-07-24ipv6: remove hard coded limitation on ipv6_pinfoEric Dumazet
IPv6 inet sockets are supposed to have a "struct ipv6_pinfo" field at the end of their definition, so that inet6_sk_generic() can derive from socket size the offset of the "struct ipv6_pinfo". This is very fragile, and prevents adding bigger alignment in sockets, because inet6_sk_generic() does not work if the compiler adds padding after the ipv6_pinfo component. We are currently working on a patch series to reorganize TCP structures for better data locality and found issues similar to the one fixed in commit f5d547676ca0 ("tcp: fix tcp_inet6_sk() for 32bit kernels") Alternative would be to force an alignment on "struct ipv6_pinfo", greater or equal to __alignof__(any ipv6 sock) to ensure there is no padding. This does not look great. v2: fix typo in mptcp_proto_v6_init() (Paolo) Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Chao Wu <wwchao@google.com> Cc: Wei Wang <weiwan@google.com> Cc: Coco Li <lixiaoyan@google.com> Cc: YiFei Zhu <zhuyifei@google.com> Reviewed-by: Simon Horman <simon.horman@corigine.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2023-07-05mptcp: do not rely on implicit state check in mptcp_listen()Paolo Abeni
Since the blamed commit, closing the first subflow resets the first subflow socket state to SS_UNCONNECTED. The current mptcp listen implementation relies only on such state to prevent touching not-fully-disconnected sockets. Incoming mptcp fastclose (or paired endpoint removal) unconditionally closes the first subflow. All the above allows an incoming fastclose followed by a listen() call to successfully race with a blocking recvmsg(), potentially causing the latter to hit a divide by zero bug in cleanup_rbuf/__tcp_select_window(). Address the issue explicitly checking the msk socket state in mptcp_listen(). An alternative solution would be moving the first subflow socket state update into mptcp_disconnect(), but in the long term the first subflow socket should be removed: better avoid relaying on it for internal consistency check. Fixes: b29fcfb54cd7 ("mptcp: full disconnect implementation") Cc: stable@vger.kernel.org Reported-by: Christoph Paasch <cpaasch@apple.com> Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/414 Signed-off-by: Paolo Abeni <pabeni@redhat.com> Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net> Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2023-07-05mptcp: ensure subflow is unhashed before cleaning the backlogPaolo Abeni
While tacking care of the mptcp-level listener I unintentionally moved the subflow level unhash after the subflow listener backlog cleanup. That could cause some nasty race and makes the code harder to read. Address the issue restoring the proper order of operations. Fixes: 57fc0f1ceaa4 ("mptcp: ensure listener is unhashed before updating the sk status") Cc: stable@vger.kernel.org Signed-off-by: Paolo Abeni <pabeni@redhat.com> Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net> Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2023-06-24sock: Remove ->sendpage*() in favour of sendmsg(MSG_SPLICE_PAGES)David Howells
Remove ->sendpage() and ->sendpage_locked(). sendmsg() with MSG_SPLICE_PAGES should be used instead. This allows multiple pages and multipage folios to be passed through. Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: Marc Kleine-Budde <mkl@pengutronix.de> # for net/can cc: Jens Axboe <axboe@kernel.dk> cc: Matthew Wilcox <willy@infradead.org> cc: linux-afs@lists.infradead.org cc: mptcp@lists.linux.dev cc: rds-devel@oss.oracle.com cc: tipc-discussion@lists.sourceforge.net cc: virtualization@lists.linux-foundation.org Link: https://lore.kernel.org/r/20230623225513.2732256-16-dhowells@redhat.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-06-22Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski
Cross-merge networking fixes after downstream PR. Conflicts: tools/testing/selftests/net/fcnal-test.sh d7a2fc1437f7 ("selftests: net: fcnal-test: check if FIPS mode is enabled") dd017c72dde6 ("selftests: fcnal: Test SO_DONTROUTE on TCP sockets.") https://lore.kernel.org/all/5007b52c-dd16-dbf6-8d64-b9701bfa498b@tessares.net/ https://lore.kernel.org/all/20230619105427.4a0df9b3@canb.auug.org.au/ No adjacent changes. Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-06-21mptcp: consolidate transition to TCP_CLOSE in mptcp_do_fastclose()Paolo Abeni
The MPTCP code always set the msk state to TCP_CLOSE before calling performing the fast-close. Move such state transition in mptcp_do_fastclose() to avoid some code duplication. Signed-off-by: Paolo Abeni <pabeni@redhat.com> Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net> Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-06-21mptcp: add subflow unique idPaolo Abeni
The user-space need to properly account the data received/sent by individual subflows. When additional subflows are created and/or closed during the MPTCP socket lifetime, the information currently exposed via MPTCP_TCPINFO are not enough: subflows are identified only by the sequential position inside the info dumps, and that will change with the above mentioned events. To solve the above problem, this patch introduces a new subflow identifier that is unique inside the given MPTCP socket scope. The initial subflow get the id 1 and the other subflows get incremental values at join time. Link: https://github.com/multipath-tcp/mptcp_net-next/issues/388 Signed-off-by: Paolo Abeni <pabeni@redhat.com> Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net> Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-06-21mptcp: track some aggregate data countersPaolo Abeni
Currently there are no data transfer counters accounting for all the subflows used by a given MPTCP socket. The user-space can compute such figures aggregating the subflow info, but that is inaccurate if any subflow is closed before the MPTCP socket itself. Add the new counters in the MPTCP socket itself and expose them via the existing diag and sockopt. While touching mptcp_diag_fill_info(), acquire the relevant locks before fetching the msk data, to ensure better data consistency Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/385 Signed-off-by: Paolo Abeni <pabeni@redhat.com> Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net> Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-06-21mptcp: move snd_una update earlier for fallback socketPaolo Abeni
That will avoid an unneeded conditional in both the fast-path and in the fallback case and will simplify a bit the next patch. Signed-off-by: Paolo Abeni <pabeni@redhat.com> Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net> Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-06-21mptcp: ensure listener is unhashed before updating the sk statusPaolo Abeni
The MPTCP protocol access the listener subflow in a lockless manner in a couple of places (poll, diag). That works only if the msk itself leaves the listener status only after that the subflow itself has been closed/disconnected. Otherwise we risk deadlock in diag, as reported by Christoph. Address the issue ensuring that the first subflow (the listener one) is always disconnected before updating the msk socket status. Reported-by: Christoph Paasch <cpaasch@apple.com> Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/407 Fixes: b29fcfb54cd7 ("mptcp: full disconnect implementation") Cc: stable@vger.kernel.org Signed-off-by: Paolo Abeni <pabeni@redhat.com> Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net> Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-06-21mptcp: drop legacy code around RX EOFPaolo Abeni
Thanks to the previous patch -- "mptcp: consolidate fallback and non fallback state machine" -- we can finally drop the "temporary hack" used to detect rx eof. Signed-off-by: Paolo Abeni <pabeni@redhat.com> Reviewed-by: Mat Martineau <martineau@kernel.org> Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-06-21mptcp: consolidate fallback and non fallback state machinePaolo Abeni
An orphaned msk releases the used resources via the worker, when the latter first see the msk in CLOSED status. If the msk status transitions to TCP_CLOSE in the release callback invoked by the worker's final release_sock(), such instance of the workqueue will not take any action. Additionally the MPTCP code prevents scheduling the worker once the socket reaches the CLOSE status: such msk resources will be leaked. The only code path that can trigger the above scenario is the __mptcp_check_send_data_fin() in fallback mode. Address the issue removing the special handling of fallback socket in __mptcp_check_send_data_fin(), consolidating the state machine for fallback and non fallback socket. Since non-fallback sockets do not send and do not receive data_fin, the mptcp code can update the msk internal status to match the next step in the SM every time data fin (ack) should be generated or received. As a consequence we can remove a bunch of checks for fallback from the fastpath. Fixes: 6e628cd3a8f7 ("mptcp: use mptcp release_cb for delayed tasks") Cc: stable@vger.kernel.org Signed-off-by: Paolo Abeni <pabeni@redhat.com> Reviewed-by: Mat Martineau <martineau@kernel.org> Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-06-21mptcp: fix possible list corruption on passive MPJPaolo Abeni
At passive MPJ time, if the msk socket lock is held by the user, the new subflow is appended to the msk->join_list under the msk data lock. In mptcp_release_cb()/__mptcp_flush_join_list(), the subflows in that list are moved from the join_list into the conn_list under the msk socket lock. Append and removal could race, possibly corrupting such list. Address the issue splicing the join list into a temporary one while still under the msk data lock. Found by code inspection, the race itself should be almost impossible to trigger in practice. Fixes: 3e5014909b56 ("mptcp: cleanup MPJ subflow list handling") Cc: stable@vger.kernel.org Signed-off-by: Paolo Abeni <pabeni@redhat.com> Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net> Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-06-21mptcp: fix possible divide by zero in recvmsg()Paolo Abeni
Christoph reported a divide by zero bug in mptcp_recvmsg(): divide error: 0000 [#1] PREEMPT SMP CPU: 1 PID: 19978 Comm: syz-executor.6 Not tainted 6.4.0-rc2-gffcc7899081b #20 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.11.0-2.el7 04/01/2014 RIP: 0010:__tcp_select_window+0x30e/0x420 net/ipv4/tcp_output.c:3018 Code: 11 ff 0f b7 cd c1 e9 0c b8 ff ff ff ff d3 e0 89 c1 f7 d1 01 cb 21 c3 eb 17 e8 2e 83 11 ff 31 db eb 0e e8 25 83 11 ff 89 d8 99 <f7> 7c 24 04 29 d3 65 48 8b 04 25 28 00 00 00 48 3b 44 24 10 75 60 RSP: 0018:ffffc90000a07a18 EFLAGS: 00010246 RAX: 000000000000ffd7 RBX: 000000000000ffd7 RCX: 0000000000040000 RDX: 0000000000000000 RSI: 000000000003ffff RDI: 0000000000040000 RBP: 000000000000ffd7 R08: ffffffff820cf297 R09: 0000000000000001 R10: 0000000000000000 R11: ffffffff8103d1a0 R12: 0000000000003f00 R13: 0000000000300000 R14: ffff888101cf3540 R15: 0000000000180000 FS: 00007f9af4c09640(0000) GS:ffff88813bd00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b33824000 CR3: 000000012f241001 CR4: 0000000000170ee0 Call Trace: <TASK> __tcp_cleanup_rbuf+0x138/0x1d0 net/ipv4/tcp.c:1611 mptcp_recvmsg+0xcb8/0xdd0 net/mptcp/protocol.c:2034 inet_recvmsg+0x127/0x1f0 net/ipv4/af_inet.c:861 ____sys_recvmsg+0x269/0x2b0 net/socket.c:1019 ___sys_recvmsg+0xe6/0x260 net/socket.c:2764 do_recvmmsg+0x1a5/0x470 net/socket.c:2858 __do_sys_recvmmsg net/socket.c:2937 [inline] __se_sys_recvmmsg net/socket.c:2953 [inline] __x64_sys_recvmmsg+0xa6/0x130 net/socket.c:2953 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x47/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x72/0xdc RIP: 0033:0x7f9af58fc6a9 Code: 5c c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 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 8b 0d 4f 37 0d 00 f7 d8 64 89 01 48 RSP: 002b:00007f9af4c08cd8 EFLAGS: 00000246 ORIG_RAX: 000000000000012b RAX: ffffffffffffffda RBX: 00000000006bc050 RCX: 00007f9af58fc6a9 RDX: 0000000000000001 RSI: 0000000020000140 RDI: 0000000000000004 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000f00 R11: 0000000000000246 R12: 00000000006bc05c R13: fffffffffffffea8 R14: 00000000006bc050 R15: 000000000001fe40 </TASK> mptcp_recvmsg is allowed to release the msk socket lock when blocking, and before re-acquiring it another thread could have switched the sock to TCP_LISTEN status - with a prior connect(AF_UNSPEC) - also clearing icsk_ack.rcv_mss. Address the issue preventing the disconnect if some other process is concurrently performing a blocking syscall on the same socket, alike commit 4faeee0cf8a5 ("tcp: deny tcp_disconnect() when threads are waiting"). Fixes: a6b118febbab ("mptcp: add receive buffer auto-tuning") Cc: stable@vger.kernel.org Reported-by: Christoph Paasch <cpaasch@apple.com> Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/404 Signed-off-by: Paolo Abeni <pabeni@redhat.com> Tested-by: Christoph Paasch <cpaasch@apple.com> Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net> Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-06-21mptcp: handle correctly disconnect() failuresPaolo Abeni
Currently the mptcp code has assumes that disconnect() can fail only at mptcp_sendmsg_fastopen() time - to avoid a deadlock scenario - and don't even bother returning an error code. Soon mptcp_disconnect() will handle more error conditions: let's track them explicitly. As a bonus, explicitly annotate TCP-level disconnect as not failing: the mptcp code never blocks for event on the subflows. Fixes: 7d803344fdc3 ("mptcp: fix deadlock in fastopen error path") Cc: stable@vger.kernel.org Signed-off-by: Paolo Abeni <pabeni@redhat.com> Tested-by: Christoph Paasch <cpaasch@apple.com> Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net> Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-06-15net: ioctl: Use kernel memory on protocol ioctl callbacksBreno Leitao
Most of the ioctls to net protocols operates directly on userspace argument (arg). Usually doing get_user()/put_user() directly in the ioctl callback. This is not flexible, because it is hard to reuse these functions without passing userspace buffers. Change the "struct proto" ioctls to avoid touching userspace memory and operate on kernel buffers, i.e., all protocol's ioctl callbacks is adapted to operate on a kernel memory other than on userspace (so, no more {put,get}_user() and friends being called in the ioctl callback). This changes the "struct proto" ioctl format in the following way: int (*ioctl)(struct sock *sk, int cmd, - unsigned long arg); + int *karg); (Important to say that this patch does not touch the "struct proto_ops" protocols) So, the "karg" argument, which is passed to the ioctl callback, is a pointer allocated to kernel space memory (inside a function wrapper). This buffer (karg) may contain input argument (copied from userspace in a prep function) and it might return a value/buffer, which is copied back to userspace if necessary. There is not one-size-fits-all format (that is I am using 'may' above), but basically, there are three type of ioctls: 1) Do not read from userspace, returns a result to userspace 2) Read an input parameter from userspace, and does not return anything to userspace 3) Read an input from userspace, and return a buffer to userspace. The default case (1) (where no input parameter is given, and an "int" is returned to userspace) encompasses more than 90% of the cases, but there are two other exceptions. Here is a list of exceptions: * Protocol RAW: * cmd = SIOCGETVIFCNT: * input and output = struct sioc_vif_req * cmd = SIOCGETSGCNT * input and output = struct sioc_sg_req * Explanation: for the SIOCGETVIFCNT case, userspace passes the input argument, which is struct sioc_vif_req. Then the callback populates the struct, which is copied back to userspace. * Protocol RAW6: * cmd = SIOCGETMIFCNT_IN6 * input and output = struct sioc_mif_req6 * cmd = SIOCGETSGCNT_IN6 * input and output = struct sioc_sg_req6 * Protocol PHONET: * cmd == SIOCPNADDRESOURCE | SIOCPNDELRESOURCE * input int (4 bytes) * Nothing is copied back to userspace. For the exception cases, functions sock_sk_ioctl_inout() will copy the userspace input, and copy it back to kernel space. The wrapper that prepare the buffer and put the buffer back to user is sk_ioctl(), so, instead of calling sk->sk_prot->ioctl(), the callee now calls sk_ioctl(), which will handle all cases. Signed-off-by: Breno Leitao <leitao@debian.org> Reviewed-by: Willem de Bruijn <willemb@google.com> Reviewed-by: David Ahern <dsahern@kernel.org> Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com> Link: https://lore.kernel.org/r/20230609152800.830401-1-leitao@debian.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-06-01Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski
Cross-merge networking fixes after downstream PR. No conflicts. Adjacent changes: drivers/net/ethernet/sfc/tc.c 622ab656344a ("sfc: fix error unwinds in TC offload") b6583d5e9e94 ("sfc: support TC decap rules matching on enc_src_port") net/mptcp/protocol.c 5b825727d087 ("mptcp: add annotations around msk->subflow accesses") e76c8ef5cc5b ("mptcp: refactor mptcp_stream_accept()") Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-06-01mptcp: fix active subflow finalizationPaolo Abeni
Active subflow are inserted into the connection list at creation time. When the MPJ handshake completes successfully, a new subflow creation netlink event is generated correctly, but the current code wrongly avoid initializing a couple of subflow data. The above will cause misbehavior on a few exceptional events: unneeded mptcp-level retransmission on msk-level sequence wrap-around and infinite mapping fallback even when a MPJ socket is present. Address the issue factoring out the needed initialization in a new helper and invoking the latter from __mptcp_finish_join() time for passive subflow and from mptcp_finish_join() for active ones. Fixes: 0530020a7c8f ("mptcp: track and update contiguous data status") Cc: stable@vger.kernel.org Reviewed-by: Mat Martineau <martineau@kernel.org> Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: Mat Martineau <martineau@kernel.org> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-06-01mptcp: add annotations around sk->sk_shutdown accessesPaolo Abeni
Christoph reported the mptcp variant of a recently addressed plain TCP issue. Similar to commit e14cadfd80d7 ("tcp: add annotations around sk->sk_shutdown accesses") add READ/WRITE ONCE annotations to silence KCSAN reports around lockless sk_shutdown access. Fixes: 71ba088ce0aa ("mptcp: cleanup accept and poll") Reported-by: Christoph Paasch <cpaasch@apple.com> Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/401 Reviewed-by: Mat Martineau <martineau@kernel.org> Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: Mat Martineau <martineau@kernel.org> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-06-01mptcp: fix data race around msk->first accessPaolo Abeni
The first subflow socket is accessed outside the msk socket lock by mptcp_subflow_fail(), we need to annotate each write access with WRITE_ONCE, but a few spots still lacks it. Fixes: 76a13b315709 ("mptcp: invoke MP_FAIL response when needed") Reviewed-by: Mat Martineau <martineau@kernel.org> Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: Mat Martineau <martineau@kernel.org> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-06-01mptcp: consolidate passive msk socket initializationPaolo Abeni
When the msk socket is cloned at MPC handshake time, a few fields are initialized in a racy way outside mptcp_sk_clone() and the msk socket lock. The above is due historical reasons: before commit a88d0092b24b ("mptcp: simplify subflow_syn_recv_sock()") as the first subflow socket carrying all the needed date was not available yet at msk creation time We can now refactor the code moving the missing initialization bit under the socket lock, removing the init race and avoiding some code duplication. This will also simplify the next patch, as all msk->first write access are now under the msk socket lock. Fixes: 0397c6d85f9c ("mptcp: keep unaccepted MPC subflow into join list") Reviewed-by: Mat Martineau <martineau@kernel.org> Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: Mat Martineau <martineau@kernel.org> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-06-01mptcp: add annotations around msk->subflow accessesPaolo Abeni
The MPTCP can access the first subflow socket in a few spots outside the socket lock scope. That is actually safe, as MPTCP will delete the socket itself only after the msk sock close(). Still the such accesses causes a few KCSAN splats, as reported by Christoph. Silence the harmless warning adding a few annotation around the relevant accesses. Fixes: 71ba088ce0aa ("mptcp: cleanup accept and poll") Reported-by: Christoph Paasch <cpaasch@apple.com> Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/402 Reviewed-by: Mat Martineau <martineau@kernel.org> Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: Mat Martineau <martineau@kernel.org> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-06-01mptcp: fix connect timeout handlingPaolo Abeni
Ondrej reported a functional issue WRT timeout handling on connect with a nice reproducer. The problem is that the current mptcp connect waits for both the MPTCP socket level timeout, and the first subflow socket timeout. The latter is not influenced/touched by the exposed setsockopt(). Overall the above makes the SO_SNDTIMEO a no-op on connect. Since mptcp_connect is invoked via inet_stream_connect and the latter properly handle the MPTCP level timeout, we can address the issue making the nested subflow level connect always unblocking. This also allow simplifying a bit the code, dropping an ugly hack to handle the fastopen and custom proto_ops connect. The issues predates the blamed commit below, but the current resolution requires the infrastructure introduced there. Fixes: 54f1944ed6d2 ("mptcp: factor out mptcp_connect()") Reported-by: Ondrej Mosnacek <omosnace@redhat.com> Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/399 Cc: stable@vger.kernel.org Reviewed-by: Mat Martineau <martineau@kernel.org> Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: Mat Martineau <martineau@kernel.org> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-05-18mptcp: refactor mptcp_stream_accept()Paolo Abeni
Rewrite the mptcp socket accept op, leveraging the new __inet_accept() helper. This way we can avoid acquiring the new socket lock twice and we can avoid a couple of indirect calls. Signed-off-by: Paolo Abeni <pabeni@redhat.com> Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net> Signed-off-by: Mat Martineau <martineau@kernel.org> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-04-20Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski
Adjacent changes: net/mptcp/protocol.h 63740448a32e ("mptcp: fix accept vs worker race") 2a6a870e44dd ("mptcp: stops worker on unaccepted sockets at listener close") ddb1a072f858 ("mptcp: move first subflow allocation at mpc access time") Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-04-19mptcp: fix accept vs worker racePaolo Abeni
The mptcp worker and mptcp_accept() can race, as reported by Christoph: refcount_t: addition on 0; use-after-free. WARNING: CPU: 1 PID: 14351 at lib/refcount.c:25 refcount_warn_saturate+0x105/0x1b0 lib/refcount.c:25 Modules linked in: CPU: 1 PID: 14351 Comm: syz-executor.2 Not tainted 6.3.0-rc1-gde5e8fd0123c #11 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.11.0-2.el7 04/01/2014 RIP: 0010:refcount_warn_saturate+0x105/0x1b0 lib/refcount.c:25 Code: 02 31 ff 89 de e8 1b f0 a7 ff 84 db 0f 85 6e ff ff ff e8 3e f5 a7 ff 48 c7 c7 d8 c7 34 83 c6 05 6d 2d 0f 02 01 e8 cb 3d 90 ff <0f> 0b e9 4f ff ff ff e8 1f f5 a7 ff 0f b6 1d 54 2d 0f 02 31 ff 89 RSP: 0018:ffffc90000a47bf8 EFLAGS: 00010282 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000 RDX: ffff88802eae98c0 RSI: ffffffff81097d4f RDI: 0000000000000001 RBP: ffff88802e712180 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000001 R11: ffff88802eaea148 R12: ffff88802e712100 R13: ffff88802e712a88 R14: ffff888005cb93a8 R15: ffff88802e712a88 FS: 0000000000000000(0000) GS:ffff88803ed00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f277fd89120 CR3: 0000000035486002 CR4: 0000000000370ee0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> __refcount_add include/linux/refcount.h:199 [inline] __refcount_inc include/linux/refcount.h:250 [inline] refcount_inc include/linux/refcount.h:267 [inline] sock_hold include/net/sock.h:775 [inline] __mptcp_close+0x4c6/0x4d0 net/mptcp/protocol.c:3051 mptcp_close+0x24/0xe0 net/mptcp/protocol.c:3072 inet_release+0x56/0xa0 net/ipv4/af_inet.c:429 __sock_release+0x51/0xf0 net/socket.c:653 sock_close+0x18/0x20 net/socket.c:1395 __fput+0x113/0x430 fs/file_table.c:321 task_work_run+0x96/0x100 kernel/task_work.c:179 exit_task_work include/linux/task_work.h:38 [inline] do_exit+0x4fc/0x10c0 kernel/exit.c:869 do_group_exit+0x51/0xf0 kernel/exit.c:1019 get_signal+0x12b0/0x1390 kernel/signal.c:2859 arch_do_signal_or_restart+0x25/0x260 arch/x86/kernel/signal.c:306 exit_to_user_mode_loop kernel/entry/common.c:168 [inline] exit_to_user_mode_prepare+0x131/0x1a0 kernel/entry/common.c:203 __syscall_exit_to_user_mode_work kernel/entry/common.c:285 [inline] syscall_exit_to_user_mode+0x19/0x40 kernel/entry/common.c:296 do_syscall_64+0x46/0x90 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x72/0xdc RIP: 0033:0x7fec4b4926a9 Code: Unable to access opcode bytes at 0x7fec4b49267f. RSP: 002b:00007fec49f9dd78 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: fffffffffffffe00 RBX: 00000000006bc058 RCX: 00007fec4b4926a9 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00000000006bc058 RBP: 00000000006bc050 R08: 00000000007df998 R09: 00000000007df998 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000006bc05c R13: fffffffffffffea8 R14: 000000000000000b R15: 000000000001fe40 </TASK> The root cause is that the worker can force fallback to TCP the first mptcp subflow, actually deleting the unaccepted msk socket. We can explicitly prevent the race delaying the unaccepted msk deletion at listener shutdown time. In case the closed subflow is later accepted, just drop the mptcp context and let the user-space deal with the paired mptcp socket. Fixes: b6985b9b8295 ("mptcp: use the workqueue to destroy unaccepted sockets") Cc: stable@vger.kernel.org Reported-by: Christoph Paasch <cpaasch@apple.com> Link: https://github.com/multipath-tcp/mptcp_net-next/issues/375 Signed-off-by: Paolo Abeni <pabeni@redhat.com> Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net> Tested-by: Christoph Paasch <cpaasch@apple.com> Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2023-04-19mptcp: stops worker on unaccepted sockets at listener closePaolo Abeni
This is a partial revert of the blamed commit, with a relevant change: mptcp_subflow_queue_clean() now just change the msk socket status and stop the worker, so that the UaF issue addressed by the blamed commit is not re-introduced. The above prevents the mptcp worker from running concurrently with inet_csk_listen_stop(), as such race would trigger a warning, as reported by Christoph: RSP: 002b:00007f784fe09cd8 EFLAGS: 00000246 ORIG_RAX: 000000000000002e WARNING: CPU: 0 PID: 25807 at net/ipv4/inet_connection_sock.c:1387 inet_csk_listen_stop+0x664/0x870 net/ipv4/inet_connection_sock.c:1387 RAX: ffffffffffffffda RBX: 00000000006bc050 RCX: 00007f7850afd6a9 RDX: 0000000000000000 RSI: 0000000020000340 RDI: 0000000000000004 Modules linked in: RBP: 0000000000000002 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000006bc05c R13: fffffffffffffea8 R14: 00000000006bc050 R15: 000000000001fe40 </TASK> CPU: 0 PID: 25807 Comm: syz-executor.7 Not tainted 6.2.0-g778e54711659 #7 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.11.0-2.el7 04/01/2014 RIP: 0010:inet_csk_listen_stop+0x664/0x870 net/ipv4/inet_connection_sock.c:1387 RAX: 0000000000000000 RBX: ffff888100dfbd40 RCX: 0000000000000000 RDX: ffff8881363aab80 RSI: ffffffff81c494f4 RDI: 0000000000000005 RBP: ffff888126dad080 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000000 R12: ffff888100dfe040 R13: 0000000000000001 R14: 0000000000000000 R15: ffff888100dfbdd8 FS: 00007f7850a2c800(0000) GS:ffff88813bc00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b32d26000 CR3: 000000012fdd8006 CR4: 0000000000770ef0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 PKRU: 55555554 Call Trace: <TASK> __tcp_close+0x5b2/0x620 net/ipv4/tcp.c:2875 __mptcp_close_ssk+0x145/0x3d0 net/mptcp/protocol.c:2427 mptcp_destroy_common+0x8a/0x1c0 net/mptcp/protocol.c:3277 mptcp_destroy+0x41/0x60 net/mptcp/protocol.c:3304 __mptcp_destroy_sock+0x56/0x140 net/mptcp/protocol.c:2965 __mptcp_close+0x38f/0x4a0 net/mptcp/protocol.c:3057 mptcp_close+0x24/0xe0 net/mptcp/protocol.c:3072 inet_release+0x53/0xa0 net/ipv4/af_inet.c:429 __sock_release+0x4e/0xf0 net/socket.c:651 sock_close+0x15/0x20 net/socket.c:1393 __fput+0xff/0x420 fs/file_table.c:321 task_work_run+0x8b/0xe0 kernel/task_work.c:179 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline] exit_to_user_mode_loop kernel/entry/common.c:171 [inline] exit_to_user_mode_prepare+0x113/0x120 kernel/entry/common.c:203 __syscall_exit_to_user_mode_work kernel/entry/common.c:285 [inline] syscall_exit_to_user_mode+0x1d/0x40 kernel/entry/common.c:296 do_syscall_64+0x46/0x90 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x72/0xdc RIP: 0033:0x7f7850af70dc RAX: 0000000000000000 RBX: 0000000000000004 RCX: 00007f7850af70dc RDX: 00007f7850a2c800 RSI: 0000000000000002 RDI: 0000000000000003 RBP: 00000000006bd980 R08: 0000000000000000 R09: 00000000000018a0 R10: 00000000316338a4 R11: 0000000000000293 R12: 0000000000211e31 R13: 00000000006bc05c R14: 00007f785062c000 R15: 0000000000211af0 Fixes: 0a3f4f1f9c27 ("mptcp: fix UaF in listener shutdown") Cc: stable@vger.kernel.org Reported-by: Christoph Paasch <cpaasch@apple.com> Link: https://github.com/multipath-tcp/mptcp_net-next/issues/371 Signed-off-by: Paolo Abeni <pabeni@redhat.com> Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net> Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net> Signed-off-by: David S. Miller <davem@davemloft.net>
generated by cgit (git 2.34.1) at 2025-06-15 11:42:06 +0000