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2025-01-09mptcp: sysctl: blackhole timeout: avoid using current->nsproxyMatthieu Baerts (NGI0)
As mentioned in the previous commit, using the 'net' structure via 'current' is not recommended for different reasons: - Inconsistency: getting info from the reader's/writer's netns vs only from the opener's netns. - current->nsproxy can be NULL in some cases, resulting in an 'Oops' (null-ptr-deref), e.g. when the current task is exiting, as spotted by syzbot [1] using acct(2). The 'pernet' structure can be obtained from the table->data using container_of(). Fixes: 27069e7cb3d1 ("mptcp: disable active MPTCP in case of blackhole") Cc: stable@vger.kernel.org Link: https://lore.kernel.org/67769ecb.050a0220.3a8527.003f.GAE@google.com [1] Suggested-by: Al Viro <viro@zeniv.linux.org.uk> Reviewed-by: Mat Martineau <martineau@kernel.org> Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org> Link: https://patch.msgid.link/20250108-net-sysctl-current-nsproxy-v1-3-5df34b2083e8@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-01-09mptcp: sysctl: sched: avoid using current->nsproxyMatthieu Baerts (NGI0)
Using the 'net' structure via 'current' is not recommended for different reasons. First, if the goal is to use it to read or write per-netns data, this is inconsistent with how the "generic" sysctl entries are doing: directly by only using pointers set to the table entry, e.g. table->data. Linked to that, the per-netns data should always be obtained from the table linked to the netns it had been created for, which may not coincide with the reader's or writer's netns. Another reason is that access to current->nsproxy->netns can oops if attempted when current->nsproxy had been dropped when the current task is exiting. This is what syzbot found, when using acct(2): Oops: general protection fault, probably for non-canonical address 0xdffffc0000000005: 0000 [#1] PREEMPT SMP KASAN PTI KASAN: null-ptr-deref in range [0x0000000000000028-0x000000000000002f] CPU: 1 UID: 0 PID: 5924 Comm: syz-executor Not tainted 6.13.0-rc5-syzkaller-00004-gccb98ccef0e5 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 RIP: 0010:proc_scheduler+0xc6/0x3c0 net/mptcp/ctrl.c:125 Code: 03 42 80 3c 38 00 0f 85 fe 02 00 00 4d 8b a4 24 08 09 00 00 48 b8 00 00 00 00 00 fc ff df 49 8d 7c 24 28 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 cc 02 00 00 4d 8b 7c 24 28 48 8d 84 24 c8 00 00 RSP: 0018:ffffc900034774e8 EFLAGS: 00010206 RAX: dffffc0000000000 RBX: 1ffff9200068ee9e RCX: ffffc90003477620 RDX: 0000000000000005 RSI: ffffffff8b08f91e RDI: 0000000000000028 RBP: 0000000000000001 R08: ffffc90003477710 R09: 0000000000000040 R10: 0000000000000040 R11: 00000000726f7475 R12: 0000000000000000 R13: ffffc90003477620 R14: ffffc90003477710 R15: dffffc0000000000 FS: 0000000000000000(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fee3cd452d8 CR3: 000000007d116000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> proc_sys_call_handler+0x403/0x5d0 fs/proc/proc_sysctl.c:601 __kernel_write_iter+0x318/0xa80 fs/read_write.c:612 __kernel_write+0xf6/0x140 fs/read_write.c:632 do_acct_process+0xcb0/0x14a0 kernel/acct.c:539 acct_pin_kill+0x2d/0x100 kernel/acct.c:192 pin_kill+0x194/0x7c0 fs/fs_pin.c:44 mnt_pin_kill+0x61/0x1e0 fs/fs_pin.c:81 cleanup_mnt+0x3ac/0x450 fs/namespace.c:1366 task_work_run+0x14e/0x250 kernel/task_work.c:239 exit_task_work include/linux/task_work.h:43 [inline] do_exit+0xad8/0x2d70 kernel/exit.c:938 do_group_exit+0xd3/0x2a0 kernel/exit.c:1087 get_signal+0x2576/0x2610 kernel/signal.c:3017 arch_do_signal_or_restart+0x90/0x7e0 arch/x86/kernel/signal.c:337 exit_to_user_mode_loop kernel/entry/common.c:111 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0x150/0x2a0 kernel/entry/common.c:218 do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fee3cb87a6a Code: Unable to access opcode bytes at 0x7fee3cb87a40. RSP: 002b:00007fffcccac688 EFLAGS: 00000202 ORIG_RAX: 0000000000000037 RAX: 0000000000000000 RBX: 00007fffcccac710 RCX: 00007fee3cb87a6a RDX: 0000000000000041 RSI: 0000000000000000 RDI: 0000000000000003 RBP: 0000000000000003 R08: 00007fffcccac6ac R09: 00007fffcccacac7 R10: 00007fffcccac710 R11: 0000000000000202 R12: 00007fee3cd49500 R13: 00007fffcccac6ac R14: 0000000000000000 R15: 00007fee3cd4b000 </TASK> Modules linked in: ---[ end trace 0000000000000000 ]--- RIP: 0010:proc_scheduler+0xc6/0x3c0 net/mptcp/ctrl.c:125 Code: 03 42 80 3c 38 00 0f 85 fe 02 00 00 4d 8b a4 24 08 09 00 00 48 b8 00 00 00 00 00 fc ff df 49 8d 7c 24 28 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 cc 02 00 00 4d 8b 7c 24 28 48 8d 84 24 c8 00 00 RSP: 0018:ffffc900034774e8 EFLAGS: 00010206 RAX: dffffc0000000000 RBX: 1ffff9200068ee9e RCX: ffffc90003477620 RDX: 0000000000000005 RSI: ffffffff8b08f91e RDI: 0000000000000028 RBP: 0000000000000001 R08: ffffc90003477710 R09: 0000000000000040 R10: 0000000000000040 R11: 00000000726f7475 R12: 0000000000000000 R13: ffffc90003477620 R14: ffffc90003477710 R15: dffffc0000000000 FS: 0000000000000000(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fee3cd452d8 CR3: 000000007d116000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 ---------------- Code disassembly (best guess), 1 bytes skipped: 0: 42 80 3c 38 00 cmpb $0x0,(%rax,%r15,1) 5: 0f 85 fe 02 00 00 jne 0x309 b: 4d 8b a4 24 08 09 00 mov 0x908(%r12),%r12 12: 00 13: 48 b8 00 00 00 00 00 movabs $0xdffffc0000000000,%rax 1a: fc ff df 1d: 49 8d 7c 24 28 lea 0x28(%r12),%rdi 22: 48 89 fa mov %rdi,%rdx 25: 48 c1 ea 03 shr $0x3,%rdx * 29: 80 3c 02 00 cmpb $0x0,(%rdx,%rax,1) <-- trapping instruction 2d: 0f 85 cc 02 00 00 jne 0x2ff 33: 4d 8b 7c 24 28 mov 0x28(%r12),%r15 38: 48 rex.W 39: 8d .byte 0x8d 3a: 84 24 c8 test %ah,(%rax,%rcx,8) Here with 'net.mptcp.scheduler', the 'net' structure is not really needed, because the table->data already has a pointer to the current scheduler, the only thing needed from the per-netns data. Simply use 'data', instead of getting (most of the time) the same thing, but from a longer and indirect way. Fixes: 6963c508fd7a ("mptcp: only allow set existing scheduler for net.mptcp.scheduler") Cc: stable@vger.kernel.org Reported-by: syzbot+e364f774c6f57f2c86d1@syzkaller.appspotmail.com Closes: https://lore.kernel.org/67769ecb.050a0220.3a8527.003f.GAE@google.com Suggested-by: Al Viro <viro@zeniv.linux.org.uk> Reviewed-by: Mat Martineau <martineau@kernel.org> Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org> Link: https://patch.msgid.link/20250108-net-sysctl-current-nsproxy-v1-2-5df34b2083e8@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-01-09mptcp: sysctl: avail sched: remove write accessMatthieu Baerts (NGI0)
'net.mptcp.available_schedulers' sysctl knob is there to list available schedulers, not to modify this list. There are then no reasons to give write access to it. Nothing would have been written anyway, but no errors would have been returned, which is unexpected. Fixes: 73c900aa3660 ("mptcp: add net.mptcp.available_schedulers") Cc: stable@vger.kernel.org Reviewed-by: Mat Martineau <martineau@kernel.org> Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org> Reviewed-by: Eric Dumazet <edumazet@google.com> Link: https://patch.msgid.link/20250108-net-sysctl-current-nsproxy-v1-1-5df34b2083e8@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-09-11mptcp: disable active MPTCP in case of blackholeMatthieu Baerts (NGI0)
An MPTCP firewall blackhole can be detected if the following SYN retransmission after a fallback to "plain" TCP is accepted. In case of blackhole, a similar technique to the one in place with TFO is now used: MPTCP can be disabled for a certain period of time, 1h by default. This time period will grow exponentially when more blackhole issues get detected right after MPTCP is re-enabled and will reset to the initial value when the blackhole issue goes away. The blackhole period can be modified thanks to a new sysctl knob: blackhole_timeout. Two new MIB counters help understanding what's happening: - 'Blackhole', incremented when a blackhole is detected. - 'MPCapableSYNTXDisabled', incremented when an MPTCP connection directly falls back to TCP during the blackhole period. Because the technique is inspired by the one used by TFO, an important part of the new code is similar to what can find in tcp_fastopen.c, with some adaptations to the MPTCP case. Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/57 Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org> Link: https://patch.msgid.link/20240909-net-next-mptcp-fallback-x-mpc-v1-3-da7ebb4cd2a3@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-09-11mptcp: fallback to TCP after SYN+MPC dropsMatthieu Baerts (NGI0)
Some middleboxes might be nasty with MPTCP, and decide to drop packets with MPTCP options, instead of just dropping the MPTCP options (or letting them pass...). In this case, it sounds better to fallback to "plain" TCP after 2 retransmissions, and try again. Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/477 Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org> Reviewed-by: Eric Dumazet <edumazet@google.com> Link: https://patch.msgid.link/20240909-net-next-mptcp-fallback-x-mpc-v1-2-da7ebb4cd2a3@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-07-24sysctl: treewide: constify the ctl_table argument of proc_handlersJoel Granados
const qualify the struct ctl_table argument in the proc_handler function signatures. This is a prerequisite to moving the static ctl_table structs into .rodata data which will ensure that proc_handler function pointers cannot be modified. This patch has been generated by the following coccinelle script: ``` virtual patch @r1@ identifier ctl, write, buffer, lenp, ppos; identifier func !~ "appldata_(timer|interval)_handler|sched_(rt|rr)_handler|rds_tcp_skbuf_handler|proc_sctp_do_(hmac_alg|rto_min|rto_max|udp_port|alpha_beta|auth|probe_interval)"; @@ int func( - struct ctl_table *ctl + const struct ctl_table *ctl ,int write, void *buffer, size_t *lenp, loff_t *ppos); @r2@ identifier func, ctl, write, buffer, lenp, ppos; @@ int func( - struct ctl_table *ctl + const struct ctl_table *ctl ,int write, void *buffer, size_t *lenp, loff_t *ppos) { ... } @r3@ identifier func; @@ int func( - struct ctl_table * + const struct ctl_table * ,int , void *, size_t *, loff_t *); @r4@ identifier func, ctl; @@ int func( - struct ctl_table *ctl + const struct ctl_table *ctl ,int , void *, size_t *, loff_t *); @r5@ identifier func, write, buffer, lenp, ppos; @@ int func( - struct ctl_table * + const struct ctl_table * ,int write, void *buffer, size_t *lenp, loff_t *ppos); ``` * Code formatting was adjusted in xfs_sysctl.c to comply with code conventions. The xfs_stats_clear_proc_handler, xfs_panic_mask_proc_handler and xfs_deprecated_dointvec_minmax where adjusted. * The ctl_table argument in proc_watchdog_common was const qualified. This is called from a proc_handler itself and is calling back into another proc_handler, making it necessary to change it as part of the proc_handler migration. Co-developed-by: Thomas Weißschuh <linux@weissschuh.net> Signed-off-by: Thomas Weißschuh <linux@weissschuh.net> Co-developed-by: Joel Granados <j.granados@samsung.com> Signed-off-by: Joel Granados <j.granados@samsung.com>
2024-05-13mptcp: prefer strscpy over strcpyMatthieu Baerts (NGI0)
strcpy() performs no bounds checking on the destination buffer. This could result in linear overflows beyond the end of the buffer, leading to all kinds of misbehaviors. The safe replacement is strscpy() [1]. This is in preparation of a possible future step where all strcpy() uses will be removed in favour of strscpy() [2]. This fixes CheckPatch warnings: WARNING: Prefer strscpy over strcpy Link: https://www.kernel.org/doc/html/latest/process/deprecated.html#strcpy [1] Link: https://github.com/KSPP/linux/issues/88 [2] Reviewed-by: Geliang Tang <geliang@kernel.org> Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org> Signed-off-by: Mat Martineau <martineau@kernel.org> Link: https://lore.kernel.org/r/20240514011335.176158-6-martineau@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-05-13mptcp: add net.mptcp.available_schedulersGregory Detal
The sysctl lists the available schedulers that can be set using net.mptcp.scheduler similarly to net.ipv4.tcp_available_congestion_control. Signed-off-by: Gregory Detal <gregory.detal@gmail.com> Reviewed-by: Mat Martineau <martineau@kernel.org> Tested-by: Geliang Tang <geliang@kernel.org> Reviewed-by: Matthieu Baerts (NGI0) <matttbe@kernel.org> Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org> Signed-off-by: Mat Martineau <martineau@kernel.org> Link: https://lore.kernel.org/r/20240514011335.176158-5-martineau@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-05-09Merge 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/hisilicon/hns3/hns3pf/hclge_main.c 35d92abfbad8 ("net: hns3: fix kernel crash when devlink reload during initialization") 2a1a1a7b5fd7 ("net: hns3: add command queue trace for hns3") Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-05-07mptcp: only allow set existing scheduler for net.mptcp.schedulerGregory Detal
The current behavior is to accept any strings as inputs, this results in an inconsistent result where an unexisting scheduler can be set: # sysctl -w net.mptcp.scheduler=notdefault net.mptcp.scheduler = notdefault This patch changes this behavior by checking for existing scheduler before accepting the input. Fixes: e3b2870b6d22 ("mptcp: add a new sysctl scheduler") Cc: stable@vger.kernel.org Signed-off-by: Gregory Detal <gregory.detal@gmail.com> Reviewed-by: Matthieu Baerts (NGI0) <matttbe@kernel.org> Tested-by: Geliang Tang <geliang@kernel.org> Reviewed-by: Mat Martineau <martineau@kernel.org> Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org> Link: https://lore.kernel.org/r/20240506-upstream-net-20240506-mptcp-sched-exist-v1-1-2ed1529e521e@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-05-03net: Remove ctl_table sentinel elements from several networking subsystemsJoel Granados
This commit comes at the tail end of a greater effort to remove the empty elements at the end of the ctl_table arrays (sentinels) which will reduce the overall build time size of the kernel and run time memory bloat by ~64 bytes per sentinel (further information Link : https://lore.kernel.org/all/ZO5Yx5JFogGi%2FcBo@bombadil.infradead.org/) To avoid lots of small commits, this commit brings together network changes from (as they appear in MAINTAINERS) LLC, MPTCP, NETROM NETWORK LAYER, PHONET PROTOCOL, ROSE NETWORK LAYER, RXRPC SOCKETS, SCTP PROTOCOL, SHARED MEMORY COMMUNICATIONS (SMC), TIPC NETWORK LAYER and NETWORKING [IPSEC] * Remove sentinel element from ctl_table structs. * Replace empty array registration with the register_net_sysctl_sz call in llc_sysctl_init * Replace the for loop stop condition that tests for procname == NULL with one that depends on array size in sctp_sysctl_net_register * Remove instances where an array element is zeroed out to make it look like a sentinel in xfrm_sysctl_init. This is not longer needed and is safe after commit c899710fe7f9 ("networking: Update to register_net_sysctl_sz") added the array size to the ctl_table registration * Use a table_size variable to keep the value of ARRAY_SIZE Signed-off-by: Joel Granados <j.granados@samsung.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2024-04-22sysctl: treewide: constify ctl_table_header::ctl_table_argThomas Weißschuh
To be able to constify instances of struct ctl_tables it is necessary to remove ways through which non-const versions are exposed from the sysctl core. One of these is the ctl_table_arg member of struct ctl_table_header. Constify this reference as a prerequisite for the full constification of struct ctl_table instances. No functional change. Signed-off-by: Thomas Weißschuh <linux@weissschuh.net> Reviewed-by: Kees Cook <keescook@chromium.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2023-10-25mptcp: add a new sysctl for make after break timeoutPaolo Abeni
The MPTCP protocol allows sockets with no alive subflows to stay in ESTABLISHED status for and user-defined timeout, to allow for later subflows creation. Currently such timeout is constant - TCP_TIMEWAIT_LEN. Let the user-space configure them via a newly added sysctl, to better cope with busy servers and simplify (make them faster) the relevant pktdrill tests. Note that the new know does not apply to orphaned MPTCP socket waiting for the data_fin handshake completion: they always wait TCP_TIMEWAIT_LEN. 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/20231023-send-net-next-20231023-2-v1-1-9dc60939d371@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-08-29Merge tag 'sysctl-6.6-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux Pull sysctl updates from Luis Chamberlain: "Long ago we set out to remove the kitchen sink on kernel/sysctl.c arrays and placings sysctls to their own sybsystem or file to help avoid merge conflicts. Matthew Wilcox pointed out though that if we're going to do that we might as well also *save* space while at it and try to remove the extra last sysctl entry added at the end of each array, a sentintel, instead of bloating the kernel by adding a new sentinel with each array moved. Doing that was not so trivial, and has required slowing down the moves of kernel/sysctl.c arrays and measuring the impact on size by each new move. The complex part of the effort to help reduce the size of each sysctl is being done by the patient work of el señor Don Joel Granados. A lot of this is truly painful code refactoring and testing and then trying to measure the savings of each move and removing the sentinels. Although Joel already has code which does most of this work, experience with sysctl moves in the past shows is we need to be careful due to the slew of odd build failures that are possible due to the amount of random Kconfig options sysctls use. To that end Joel's work is split by first addressing the major housekeeping needed to remove the sentinels, which is part of this merge request. The rest of the work to actually remove the sentinels will be done later in future kernel releases. The preliminary math is showing this will all help reduce the overall build time size of the kernel and run time memory consumed by the kernel by about ~64 bytes per array where we are able to remove each sentinel in the future. That also means there is no more bloating the kernel with the extra ~64 bytes per array moved as no new sentinels are created" * tag 'sysctl-6.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux: sysctl: Use ctl_table_size as stopping criteria for list macro sysctl: SIZE_MAX->ARRAY_SIZE in register_net_sysctl vrf: Update to register_net_sysctl_sz networking: Update to register_net_sysctl_sz netfilter: Update to register_net_sysctl_sz ax.25: Update to register_net_sysctl_sz sysctl: Add size to register_net_sysctl function sysctl: Add size arg to __register_sysctl_init sysctl: Add size to register_sysctl sysctl: Add a size arg to __register_sysctl_table sysctl: Add size argument to init_header sysctl: Add ctl_table_size to ctl_table_header sysctl: Use ctl_table_header in list_for_each_table_entry sysctl: Prefer ctl_table_header in proc_sysctl
2023-08-22mptcp: add a new sysctl schedulerGeliang Tang
This patch adds a new sysctl, named scheduler, to support for selection of different schedulers. Export mptcp_get_scheduler helper to get this sysctl. 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-v1-4-0c860fb256a8@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-08-15networking: Update to register_net_sysctl_szJoel Granados
Move from register_net_sysctl to register_net_sysctl_sz for all the networking related files. Do this while making sure to mirror the NULL assignments with a table_size of zero for the unprivileged users. We need to move to the new function in preparation for when we change SIZE_MAX to ARRAY_SIZE() in the register_net_sysctl macro. Failing to do so would erroneously allow ARRAY_SIZE() to be called on a pointer. We hold off the SIZE_MAX to ARRAY_SIZE change until we have migrated all the relevant net sysctl registering functions to register_net_sysctl_sz in subsequent commits. An additional size function was added to the following files in order to calculate the size of an array that is defined in another file: include/net/ipv6.h net/ipv6/icmp.c net/ipv6/route.c net/ipv6/sysctl_net_ipv6.c Signed-off-by: Joel Granados <j.granados@samsung.com> Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
2022-04-29mptcp: Add a per-namespace sysctl to set the default path manager typeMat Martineau
The new net.mptcp.pm_type sysctl determines which path manager will be used by each newly-created MPTCP socket. v2: Handle builds without CONFIG_SYSCTL v3: Clarify logic for type-specific PM init (Geliang Tang and Paolo Abeni) 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>
2021-08-14mptcp: faster active backup recoveryPaolo Abeni
The msk can use backup subflows to transmit in-sequence data only if there are no other active subflow. On active backup scenario, the MPTCP connection can do forward progress only due to MPTCP retransmissions - rtx can pick backup subflows. This patch introduces a new flag flow MPTCP subflows: if the underlying TCP connection made no progresses for long time, and there are other less problematic subflows available, the given subflow become stale. Stale subflows are not considered active: if all non backup subflows become stale, the MPTCP scheduler can pick backup subflows for plain transmissions. Stale subflows can return in active state, as soon as any reply from the peer is observed. Active backup scenarios can now leverage the available b/w with no restrinction. Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/207 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>
2021-08-14mptcp: cleanup sysctl data and helpersPaolo Abeni
Reorder the data in mptcp_pernet to avoid wasting space with no reasons and constify the access helpers. No functional changes 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>
2021-06-22mptcp: add sysctl allow_join_initial_addr_portGeliang Tang
This patch added a new sysctl, named allow_join_initial_addr_port, to control whether allow peers to send join requests to the IP address and port number used by the initial subflow. Suggested-by: Florian Westphal <fw@strlen.de> Acked-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: Geliang Tang <geliangtang@gmail.com> Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-18mptcp: add a new sysctl checksum_enabledGeliang Tang
This patch added a new sysctl, named checksum_enabled, to control whether DSS checksum can be enabled. Acked-by: Paolo Abeni <pabeni@redhat.com> Co-developed-by: Matthieu Baerts <matthieu.baerts@tessares.net> Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net> Signed-off-by: Geliang Tang <geliangtang@gmail.com> Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-05-28mptcp: restrict values of 'enabled' sysctlMatthieu Baerts
To avoid confusions, it seems better to parse this sysctl parameter as a boolean. We use it as a boolean, no need to parse an integer and bring confusions if we see a value different from 0 and 1, especially with this parameter name: enabled. It seems fine to do this modification because the default value is 1 (enabled). Then the only other interesting value to set is 0 (disabled). All other values would not have changed the default behaviour. Suggested-by: Florian Westphal <fw@strlen.de> Acked-by: Florian Westphal <fw@strlen.de> Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net> Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-05-28mptcp: support SYSCTL only if enabledMatthieu Baerts
Since the introduction of the sysctl support in MPTCP with commit 784325e9f037 ("mptcp: new sysctl to control the activation per NS"), we don't check CONFIG_SYSCTL. Until now, that was not an issue: the register and unregister functions were replaced by NO-OP one if SYSCTL was not enabled in the config. The only thing we could have avoid is not to reserve memory for the table but that's for the moment only a small table per net-ns. But the following commit is going to use SYSCTL_ZERO and SYSCTL_ONE which are not be defined if SYSCTL is not enabled in the config. This causes 'undefined reference' errors from the linker. Reported-by: kernel test robot <lkp@intel.com> Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net> Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-11-04mptcp: add a new sysctl add_addr_timeoutGeliang Tang
This patch added a new sysctl, named add_addr_timeout, to control the timeout value (in seconds) of the ADD_ADDR retransmission. Suggested-by: Matthieu Baerts <matthieu.baerts@tessares.net> Suggested-by: Paolo Abeni <pabeni@redhat.com> Acked-by: Paolo Abeni <pabeni@redhat.com> Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net> Signed-off-by: Geliang Tang <geliangtang@gmail.com> Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-07-31mptcp: enable JOIN requests even if cookies are in useFlorian Westphal
JOIN requests do not work in syncookie mode -- for HMAC validation, the peers nonce and the mptcp token (to obtain the desired connection socket the join is for) are required, but this information is only present in the initial syn. So either we need to drop all JOIN requests once a listening socket enters syncookie mode, or we need to store enough state to reconstruct the request socket later. This adds a state table (1024 entries) to store the data present in the MP_JOIN syn request and the random nonce used for the cookie syn/ack. When a MP_JOIN ACK passed cookie validation, the table is consulted to rebuild the request socket from it. An alternate approach would be to "cancel" syn-cookie mode and force MP_JOIN to always use a syn queue entry. However, doing so brings the backlog over the configured queue limit. v2: use req->syncookie, not (removed) want_cookie arg Suggested-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: Florian Westphal <fw@strlen.de> Reviewed-by: Mat Martineau <mathew.j.martineau@linux.intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-01-24mptcp: new sysctl to control the activation per NSMatthieu Baerts
New MPTCP sockets will return -ENOPROTOOPT if MPTCP support is disabled for the current net namespace. We are providing here a way to control access to the feature for those that need to turn it on or off. The value of this new sysctl can be different per namespace. We can then restrict the usage of MPTCP to the selected NS. In case of serious issues with MPTCP, administrators can now easily turn MPTCP off. Co-developed-by: Peter Krystad <peter.krystad@linux.intel.com> Signed-off-by: Peter Krystad <peter.krystad@linux.intel.com> Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net> Signed-off-by: Christoph Paasch <cpaasch@apple.com> Signed-off-by: David S. Miller <davem@davemloft.net>