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2022-02-24mptcp: Correctly set DATA_FIN timeout when number of retransmits is largeMat Martineau
Syzkaller with UBSAN uncovered a scenario where a large number of DATA_FIN retransmits caused a shift-out-of-bounds in the DATA_FIN timeout calculation: ================================================================================ UBSAN: shift-out-of-bounds in net/mptcp/protocol.c:470:29 shift exponent 32 is too large for 32-bit type 'unsigned int' CPU: 1 PID: 13059 Comm: kworker/1:0 Not tainted 5.17.0-rc2-00630-g5fbf21c90c60 #1 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.13.0-1ubuntu1.1 04/01/2014 Workqueue: events mptcp_worker Call Trace: <TASK> __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 ubsan_epilogue+0xb/0x5a lib/ubsan.c:151 __ubsan_handle_shift_out_of_bounds.cold+0xb2/0x20e lib/ubsan.c:330 mptcp_set_datafin_timeout net/mptcp/protocol.c:470 [inline] __mptcp_retrans.cold+0x72/0x77 net/mptcp/protocol.c:2445 mptcp_worker+0x58a/0xa70 net/mptcp/protocol.c:2528 process_one_work+0x9df/0x16d0 kernel/workqueue.c:2307 worker_thread+0x95/0xe10 kernel/workqueue.c:2454 kthread+0x2f4/0x3b0 kernel/kthread.c:377 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 </TASK> ================================================================================ This change limits the maximum timeout by limiting the size of the shift, which keeps all intermediate values in-bounds. Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/259 Fixes: 6477dd39e62c ("mptcp: Retransmit DATA_FIN") Acked-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>
2022-02-24mptcp: accurate SIOCOUTQ for fallback socketPaolo Abeni
The MPTCP SIOCOUTQ implementation is not very accurate in case of fallback: it only measures the data in the MPTCP-level write queue, but it does not take in account the subflow write queue utilization. In case of fallback the first can be empty, while the latter is not. The above produces sporadic self-tests issues and can foul legit user-space application. Fix the issue additionally querying the subflow in case of fallback. Fixes: 644807e3e462 ("mptcp: add SIOCINQ, OUTQ and OUTQNSD ioctls") Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/260 Reported-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>
2022-02-19mptcp: add mibs counter for ignored incoming optionsPaolo Abeni
The MPTCP in kernel path manager has some constraints on incoming addresses announce processing, so that in edge scenarios it can end-up dropping (ignoring) some of such announces. The above is not very limiting in practice since such scenarios are very uncommon and MPTCP will recover due to ADD_ADDR retransmissions. This patch adds a few MIB counters to account for such drop events to allow easier introspection of the critical scenarios. Fixes: f7efc7771eac ("mptcp: drop argument port from mptcp_pm_announce_addr") 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>
2022-02-19mptcp: fix race in incoming ADD_ADDR option processingPaolo Abeni
If an MPTCP endpoint received multiple consecutive incoming ADD_ADDR options, mptcp_pm_add_addr_received() can overwrite the current remote address value after the PM lock is released in mptcp_pm_nl_add_addr_received() and before such address is echoed. Fix the issue caching the remote address value a little earlier and always using the cached value after releasing the PM lock. Fixes: f7efc7771eac ("mptcp: drop argument port from mptcp_pm_announce_addr") 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>
2022-02-19mptcp: fix race in overlapping signal eventsPaolo Abeni
After commit a88c9e496937 ("mptcp: do not block subflows creation on errors"), if a signal address races with a failing subflow creation, the subflow creation failure control path can trigger the selection of the next address to be announced while the current announced is still pending. The above will cause the unintended suppression of the ADD_ADDR announce. Fix the issue skipping the to-be-suppressed announce before it will mark an endpoint as already used. The relevant announce will be triggered again when the current one will complete. Fixes: a88c9e496937 ("mptcp: do not block subflows creation on errors") 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>
2022-02-09mptcp: netlink: process IPv6 addrs in creating listening socketsKishen Maloor
This change updates mptcp_pm_nl_create_listen_socket() to create listening sockets bound to IPv6 addresses (where IPv6 is supported). Fixes: 1729cf186d8a ("mptcp: create the listening socket for new port") Acked-by: Geliang Tang <geliang.tang@suse.com> Signed-off-by: Kishen Maloor <kishen.maloor@intel.com> Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-01-21mptcp: Use struct_group() to avoid cross-field memset()Kees Cook
In preparation for FORTIFY_SOURCE performing compile-time and run-time field bounds checking for memcpy(), memmove(), and memset(), avoid intentionally writing across neighboring fields. Use struct_group() to capture the fields to be reset, so that memset() can be appropriately bounds-checked by the compiler. Cc: Matthieu Baerts <matthieu.baerts@tessares.net> Cc: mptcp@lists.linux.dev Signed-off-by: Kees Cook <keescook@chromium.org> Reviewed-by: Mat Martineau <mathew.j.martineau@linux.intel.com> Link: https://lore.kernel.org/r/20220121073935.1154263-1-keescook@chromium.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-01-20mptcp: fix removing ids bitmap settingGeliang Tang
In mptcp_pm_nl_rm_addr_or_subflow(), the bit of rm_list->ids[i] in the id_avail_bitmap should be set, not rm_list->ids[1]. This patch fixed it. Fixes: 86e39e04482b ("mptcp: keep track of local endpoint still available for each msk") Acked-by: Paolo Abeni <pabeni@redhat.com> 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>
2022-01-20mptcp: fix msk traversal in mptcp_nl_cmd_set_flags()Paolo Abeni
The MPTCP endpoint list is under RCU protection, guarded by the pernet spinlock. mptcp_nl_cmd_set_flags() traverses the list without acquiring the spin-lock nor under the RCU critical section. This change addresses the issue performing the lookup and the endpoint update under the pernet spinlock. Fixes: 0f9f696a502e ("mptcp: add set_flags command in PM netlink") 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>
2022-01-09Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski
Merge in fixes directly in prep for the 5.17 merge window. No conflicts. Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-01-07mptcp: reuse __mptcp_make_csum in validate_data_csumGeliang Tang
This patch reused __mptcp_make_csum() in validate_data_csum() instead of open-coding. 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>
2022-01-07mptcp: change the parameter of __mptcp_make_csumGeliang Tang
This patch changed the type of the last parameter of __mptcp_make_csum() from __sum16 to __wsum. And export this function in protocol.h. 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>
2022-01-07mptcp: Check reclaim amount before reducing allocationMat Martineau
syzbot found a page counter underflow that was triggered by MPTCP's reclaim code: page_counter underflow: -4294964789 nr_pages=4294967295 WARNING: CPU: 2 PID: 3785 at mm/page_counter.c:56 page_counter_cancel+0xcf/0xe0 mm/page_counter.c:56 Modules linked in: CPU: 2 PID: 3785 Comm: kworker/2:6 Not tainted 5.16.0-rc1-syzkaller #0 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.14.0-2 04/01/2014 Workqueue: events mptcp_worker RIP: 0010:page_counter_cancel+0xcf/0xe0 mm/page_counter.c:56 Code: c7 04 24 00 00 00 00 45 31 f6 eb 97 e8 2a 2b b5 ff 4c 89 ea 48 89 ee 48 c7 c7 00 9e b8 89 c6 05 a0 c1 ba 0b 01 e8 95 e4 4b 07 <0f> 0b eb a8 4c 89 e7 e8 25 5a fb ff eb c7 0f 1f 00 41 56 41 55 49 RSP: 0018:ffffc90002d4f918 EFLAGS: 00010082 RAX: 0000000000000000 RBX: ffff88806a494120 RCX: 0000000000000000 RDX: ffff8880688c41c0 RSI: ffffffff815e8f28 RDI: fffff520005a9f15 RBP: ffffffff000009cb R08: 0000000000000000 R09: 0000000000000000 R10: ffffffff815e2cfe R11: 0000000000000000 R12: ffff88806a494120 R13: 00000000ffffffff R14: 0000000000000000 R15: 0000000000000001 FS: 0000000000000000(0000) GS:ffff88802cc00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b2de21000 CR3: 000000005ad59000 CR4: 0000000000150ee0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> page_counter_uncharge+0x2e/0x60 mm/page_counter.c:160 drain_stock+0xc1/0x180 mm/memcontrol.c:2219 refill_stock+0x139/0x2f0 mm/memcontrol.c:2271 __sk_mem_reduce_allocated+0x24d/0x550 net/core/sock.c:2945 __mptcp_rmem_reclaim net/mptcp/protocol.c:167 [inline] __mptcp_mem_reclaim_partial+0x124/0x410 net/mptcp/protocol.c:975 mptcp_mem_reclaim_partial net/mptcp/protocol.c:982 [inline] mptcp_alloc_tx_skb net/mptcp/protocol.c:1212 [inline] mptcp_sendmsg_frag+0x18c6/0x2190 net/mptcp/protocol.c:1279 __mptcp_push_pending+0x232/0x720 net/mptcp/protocol.c:1545 mptcp_release_cb+0xfe/0x200 net/mptcp/protocol.c:2975 release_sock+0xb4/0x1b0 net/core/sock.c:3306 mptcp_worker+0x51e/0xc10 net/mptcp/protocol.c:2443 process_one_work+0x9b2/0x1690 kernel/workqueue.c:2298 worker_thread+0x658/0x11f0 kernel/workqueue.c:2445 kthread+0x405/0x4f0 kernel/kthread.c:327 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 </TASK> __mptcp_mem_reclaim_partial() could call __mptcp_rmem_reclaim() with a negative value, which passed that negative value to __sk_mem_reduce_allocated() and triggered the splat above. Check for a reclaim amount that is positive and large enough for __mptcp_rmem_reclaim() to actually adjust rmem_fwd_alloc (much like the sk_mem_reclaim_partial() code the function is based on). v2: Use '>' instead of '>=', since SK_MEM_QUANTUM - 1 would get right-shifted into nothing by __mptcp_rmem_reclaim. Fixes: 6511882cdd82 ("mptcp: allocate fwd memory separately on the rx and tx path") Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/252 Reported-and-tested-by: syzbot+bc9e2d2dbcb347dd215a@syzkaller.appspotmail.com Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Michal Hocko <mhocko@suse.com> Acked-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 a DSS option writing errorGeliang Tang
'ptr += 1;' was omitted in the original code. If the DSS is the last option -- which is what we have most of the time -- that's not an issue. But it is if we need to send something else after like a RM_ADDR or an MP_PRIO. Fixes: 1bff1e43a30e ("mptcp: optimize out option generation") 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: David S. Miller <davem@davemloft.net>
2022-01-07mptcp: fix opt size when sending DSS + MP_FAILMatthieu Baerts
When these two options had to be sent -- which is not common -- the DSS size was not being taken into account in the remaining size. Additionally in this situation, the reported size was only the one of the MP_FAIL which can cause issue if at the end, we need to write more in the TCP options than previously said. Here we use a dedicated variable for MP_FAIL size to keep the WARN_ON_ONCE() just after. Fixes: c25aeb4e0953 ("mptcp: MP_FAIL suboption sending") Acked-and-tested-by: Geliang Tang <geliang.tang@suse.com> Signed-off-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>
2022-01-07mptcp: avoid atomic bit manipulation when possiblePaolo Abeni
Currently the msk->flags bitmask carries both state for the mptcp_release_cb() - mostly touched under the mptcp data lock - and others state info touched even outside such lock scope. As a consequence, msk->flags is always manipulated with atomic operations. This change splits such bitmask in two separate fields, so that we use plain bit operations when touching the cb-related info. The MPTCP_PUSH_PENDING bit needs additional care, as it is the only CB related field currently accessed either under the mptcp data lock or the mptcp socket lock. Let's add another mask just for such bit's sake. 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 MPJ subflow list handlingPaolo Abeni
We can simplify the join list handling leveraging the mptcp_release_cb(): if we can acquire the msk socket lock at mptcp_finish_join time, move the new subflow directly into the conn_list, otherwise place it on join_list and let the release_cb process such list. Since pending MPJ connection are now always processed in a timely way, we can avoid flushing the join list every time we have to process all the current subflows. Additionally we can now use the mptcp data lock to protect the join_list, removing the additional spin lock. Finally, the MPJ handshake is now always finalized under the msk socket lock, we can drop the additional synchronization between mptcp_finish_join() and mptcp_close(). 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: 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>