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2024-07-11udp: Set SOCK_RCU_FREE earlier in udp_lib_get_port().Kuniyuki Iwashima
syzkaller triggered the warning [0] in udp_v4_early_demux(). In udp_v[46]_early_demux() and sk_lookup(), we do not touch the refcount of the looked-up sk and use sock_pfree() as skb->destructor, so we check SOCK_RCU_FREE to ensure that the sk is safe to access during the RCU grace period. Currently, SOCK_RCU_FREE is flagged for a bound socket after being put into the hash table. Moreover, the SOCK_RCU_FREE check is done too early in udp_v[46]_early_demux() and sk_lookup(), so there could be a small race window: CPU1 CPU2 ---- ---- udp_v4_early_demux() udp_lib_get_port() | |- hlist_add_head_rcu() |- sk = __udp4_lib_demux_lookup() | |- DEBUG_NET_WARN_ON_ONCE(sk_is_refcounted(sk)); `- sock_set_flag(sk, SOCK_RCU_FREE) We had the same bug in TCP and fixed it in commit 871019b22d1b ("net: set SOCK_RCU_FREE before inserting socket into hashtable"). Let's apply the same fix for UDP. [0]: WARNING: CPU: 0 PID: 11198 at net/ipv4/udp.c:2599 udp_v4_early_demux+0x481/0xb70 net/ipv4/udp.c:2599 Modules linked in: CPU: 0 PID: 11198 Comm: syz-executor.1 Not tainted 6.9.0-g93bda33046e7 #13 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.0-0-gd239552ce722-prebuilt.qemu.org 04/01/2014 RIP: 0010:udp_v4_early_demux+0x481/0xb70 net/ipv4/udp.c:2599 Code: c5 7a 15 fe bb 01 00 00 00 44 89 e9 31 ff d3 e3 81 e3 bf ef ff ff 89 de e8 2c 74 15 fe 85 db 0f 85 02 06 00 00 e8 9f 7a 15 fe <0f> 0b e8 98 7a 15 fe 49 8d 7e 60 e8 4f 39 2f fe 49 c7 46 60 20 52 RSP: 0018:ffffc9000ce3fa58 EFLAGS: 00010293 RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffffff8318c92c RDX: ffff888036ccde00 RSI: ffffffff8318c2f1 RDI: 0000000000000001 RBP: ffff88805a2dd6e0 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000000 R11: 0001ffffffffffff R12: ffff88805a2dd680 R13: 0000000000000007 R14: ffff88800923f900 R15: ffff88805456004e FS: 00007fc449127640(0000) GS:ffff88807dc00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fc449126e38 CR3: 000000003de4b002 CR4: 0000000000770ef0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600 PKRU: 55555554 Call Trace: <TASK> ip_rcv_finish_core.constprop.0+0xbdd/0xd20 net/ipv4/ip_input.c:349 ip_rcv_finish+0xda/0x150 net/ipv4/ip_input.c:447 NF_HOOK include/linux/netfilter.h:314 [inline] NF_HOOK include/linux/netfilter.h:308 [inline] ip_rcv+0x16c/0x180 net/ipv4/ip_input.c:569 __netif_receive_skb_one_core+0xb3/0xe0 net/core/dev.c:5624 __netif_receive_skb+0x21/0xd0 net/core/dev.c:5738 netif_receive_skb_internal net/core/dev.c:5824 [inline] netif_receive_skb+0x271/0x300 net/core/dev.c:5884 tun_rx_batched drivers/net/tun.c:1549 [inline] tun_get_user+0x24db/0x2c50 drivers/net/tun.c:2002 tun_chr_write_iter+0x107/0x1a0 drivers/net/tun.c:2048 new_sync_write fs/read_write.c:497 [inline] vfs_write+0x76f/0x8d0 fs/read_write.c:590 ksys_write+0xbf/0x190 fs/read_write.c:643 __do_sys_write fs/read_write.c:655 [inline] __se_sys_write fs/read_write.c:652 [inline] __x64_sys_write+0x41/0x50 fs/read_write.c:652 x64_sys_call+0xe66/0x1990 arch/x86/include/generated/asm/syscalls_64.h:2 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0x4b/0x110 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x4b/0x53 RIP: 0033:0x7fc44a68bc1f Code: 89 54 24 18 48 89 74 24 10 89 7c 24 08 e8 e9 cf f5 ff 48 8b 54 24 18 48 8b 74 24 10 41 89 c0 8b 7c 24 08 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 31 44 89 c7 48 89 44 24 08 e8 3c d0 f5 ff 48 RSP: 002b:00007fc449126c90 EFLAGS: 00000293 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00000000004bc050 RCX: 00007fc44a68bc1f RDX: 0000000000000032 RSI: 00000000200000c0 RDI: 00000000000000c8 RBP: 00000000004bc050 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000032 R11: 0000000000000293 R12: 0000000000000000 R13: 000000000000000b R14: 00007fc44a5ec530 R15: 0000000000000000 </TASK> Fixes: 6acc9b432e67 ("bpf: Add helper to retrieve socket in BPF") Reported-by: syzkaller <syzkaller@googlegroups.com> Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Link: https://patch.msgid.link/20240709191356.24010-1-kuniyu@amazon.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2024-07-10tcp: avoid too many retransmit packetsEric Dumazet
If a TCP socket is using TCP_USER_TIMEOUT, and the other peer retracted its window to zero, tcp_retransmit_timer() can retransmit a packet every two jiffies (2 ms for HZ=1000), for about 4 minutes after TCP_USER_TIMEOUT has 'expired'. The fix is to make sure tcp_rtx_probe0_timed_out() takes icsk->icsk_user_timeout into account. Before blamed commit, the socket would not timeout after icsk->icsk_user_timeout, but would use standard exponential backoff for the retransmits. Also worth noting that before commit e89688e3e978 ("net: tcp: fix unexcepted socket die when snd_wnd is 0"), the issue would last 2 minutes instead of 4. Fixes: b701a99e431d ("tcp: Add tcp_clamp_rto_to_user_timeout() helper to improve accuracy") Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Neal Cardwell <ncardwell@google.com> Reviewed-by: Jason Xing <kerneljasonxing@gmail.com> Reviewed-by: Jon Maxwell <jmaxwell37@gmail.com> Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com> Link: https://patch.msgid.link/20240710001402.2758273-1-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-07-05tcp: fix incorrect undo caused by DSACK of TLP retransmitNeal Cardwell
Loss recovery undo_retrans bookkeeping had a long-standing bug where a DSACK from a spurious TLP retransmit packet could cause an erroneous undo of a fast recovery or RTO recovery that repaired a single really-lost packet (in a sequence range outside that of the TLP retransmit). Basically, because the loss recovery state machine didn't account for the fact that it sent a TLP retransmit, the DSACK for the TLP retransmit could erroneously be implicitly be interpreted as corresponding to the normal fast recovery or RTO recovery retransmit that plugged a real hole, thus resulting in an improper undo. For example, consider the following buggy scenario where there is a real packet loss but the congestion control response is improperly undone because of this bug: + send packets P1, P2, P3, P4 + P1 is really lost + send TLP retransmit of P4 + receive SACK for original P2, P3, P4 + enter fast recovery, fast-retransmit P1, increment undo_retrans to 1 + receive DSACK for TLP P4, decrement undo_retrans to 0, undo (bug!) + receive cumulative ACK for P1-P4 (fast retransmit plugged real hole) The fix: when we initialize undo machinery in tcp_init_undo(), if there is a TLP retransmit in flight, then increment tp->undo_retrans so that we make sure that we receive a DSACK corresponding to the TLP retransmit, as well as DSACKs for all later normal retransmits, before triggering a loss recovery undo. Note that we also have to move the line that clears tp->tlp_high_seq for RTO recovery, so that upon RTO we remember the tp->tlp_high_seq value until tcp_init_undo() and clear it only afterward. Also note that the bug dates back to the original 2013 TLP implementation, commit 6ba8a3b19e76 ("tcp: Tail loss probe (TLP)"). However, this patch will only compile and work correctly with kernels that have tp->tlp_retrans, which was added only in v5.8 in 2020 in commit 76be93fc0702 ("tcp: allow at most one TLP probe per flight"). So we associate this fix with that later commit. Fixes: 76be93fc0702 ("tcp: allow at most one TLP probe per flight") Signed-off-by: Neal Cardwell <ncardwell@google.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Cc: Yuchung Cheng <ycheng@google.com> Cc: Kevin Yang <yyd@google.com> Link: https://patch.msgid.link/20240703171246.1739561-1-ncardwell.sw@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-07-04inet_diag: Initialize pad field in struct inet_diag_req_v2Shigeru Yoshida
KMSAN reported uninit-value access in raw_lookup() [1]. Diag for raw sockets uses the pad field in struct inet_diag_req_v2 for the underlying protocol. This field corresponds to the sdiag_raw_protocol field in struct inet_diag_req_raw. inet_diag_get_exact_compat() converts inet_diag_req to inet_diag_req_v2, but leaves the pad field uninitialized. So the issue occurs when raw_lookup() accesses the sdiag_raw_protocol field. Fix this by initializing the pad field in inet_diag_get_exact_compat(). Also, do the same fix in inet_diag_dump_compat() to avoid the similar issue in the future. [1] BUG: KMSAN: uninit-value in raw_lookup net/ipv4/raw_diag.c:49 [inline] BUG: KMSAN: uninit-value in raw_sock_get+0x657/0x800 net/ipv4/raw_diag.c:71 raw_lookup net/ipv4/raw_diag.c:49 [inline] raw_sock_get+0x657/0x800 net/ipv4/raw_diag.c:71 raw_diag_dump_one+0xa1/0x660 net/ipv4/raw_diag.c:99 inet_diag_cmd_exact+0x7d9/0x980 inet_diag_get_exact_compat net/ipv4/inet_diag.c:1404 [inline] inet_diag_rcv_msg_compat+0x469/0x530 net/ipv4/inet_diag.c:1426 sock_diag_rcv_msg+0x23d/0x740 net/core/sock_diag.c:282 netlink_rcv_skb+0x537/0x670 net/netlink/af_netlink.c:2564 sock_diag_rcv+0x35/0x40 net/core/sock_diag.c:297 netlink_unicast_kernel net/netlink/af_netlink.c:1335 [inline] netlink_unicast+0xe74/0x1240 net/netlink/af_netlink.c:1361 netlink_sendmsg+0x10c6/0x1260 net/netlink/af_netlink.c:1905 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg+0x332/0x3d0 net/socket.c:745 ____sys_sendmsg+0x7f0/0xb70 net/socket.c:2585 ___sys_sendmsg+0x271/0x3b0 net/socket.c:2639 __sys_sendmsg net/socket.c:2668 [inline] __do_sys_sendmsg net/socket.c:2677 [inline] __se_sys_sendmsg net/socket.c:2675 [inline] __x64_sys_sendmsg+0x27e/0x4a0 net/socket.c:2675 x64_sys_call+0x135e/0x3ce0 arch/x86/include/generated/asm/syscalls_64.h:47 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xd9/0x1e0 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f Uninit was stored to memory at: raw_sock_get+0x650/0x800 net/ipv4/raw_diag.c:71 raw_diag_dump_one+0xa1/0x660 net/ipv4/raw_diag.c:99 inet_diag_cmd_exact+0x7d9/0x980 inet_diag_get_exact_compat net/ipv4/inet_diag.c:1404 [inline] inet_diag_rcv_msg_compat+0x469/0x530 net/ipv4/inet_diag.c:1426 sock_diag_rcv_msg+0x23d/0x740 net/core/sock_diag.c:282 netlink_rcv_skb+0x537/0x670 net/netlink/af_netlink.c:2564 sock_diag_rcv+0x35/0x40 net/core/sock_diag.c:297 netlink_unicast_kernel net/netlink/af_netlink.c:1335 [inline] netlink_unicast+0xe74/0x1240 net/netlink/af_netlink.c:1361 netlink_sendmsg+0x10c6/0x1260 net/netlink/af_netlink.c:1905 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg+0x332/0x3d0 net/socket.c:745 ____sys_sendmsg+0x7f0/0xb70 net/socket.c:2585 ___sys_sendmsg+0x271/0x3b0 net/socket.c:2639 __sys_sendmsg net/socket.c:2668 [inline] __do_sys_sendmsg net/socket.c:2677 [inline] __se_sys_sendmsg net/socket.c:2675 [inline] __x64_sys_sendmsg+0x27e/0x4a0 net/socket.c:2675 x64_sys_call+0x135e/0x3ce0 arch/x86/include/generated/asm/syscalls_64.h:47 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xd9/0x1e0 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f Local variable req.i created at: inet_diag_get_exact_compat net/ipv4/inet_diag.c:1396 [inline] inet_diag_rcv_msg_compat+0x2a6/0x530 net/ipv4/inet_diag.c:1426 sock_diag_rcv_msg+0x23d/0x740 net/core/sock_diag.c:282 CPU: 1 PID: 8888 Comm: syz-executor.6 Not tainted 6.10.0-rc4-00217-g35bb670d65fc #32 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-2.fc40 04/01/2014 Fixes: 432490f9d455 ("net: ip, diag -- Add diag interface for raw sockets") Reported-by: syzkaller <syzkaller@googlegroups.com> Signed-off-by: Shigeru Yoshida <syoshida@redhat.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Link: https://patch.msgid.link/20240703091649.111773-1-syoshida@redhat.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2024-07-04tcp: Don't flag tcp_sk(sk)->rx_opt.saw_unknown for TCP AO.Kuniyuki Iwashima
When we process segments with TCP AO, we don't check it in tcp_parse_options(). Thus, opt_rx->saw_unknown is set to 1, which unconditionally triggers the BPF TCP option parser. Let's avoid the unnecessary BPF invocation. Fixes: 0a3a809089eb ("net/tcp: Verify inbound TCP-AO signed segments") Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Acked-by: Dmitry Safonov <0x7f454c46@gmail.com> Link: https://patch.msgid.link/20240703033508.6321-1-kuniyu@amazon.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2024-07-01tcp_metrics: validate source addr lengthJakub Kicinski
I don't see anything checking that TCP_METRICS_ATTR_SADDR_IPV4 is at least 4 bytes long, and the policy doesn't have an entry for this attribute at all (neither does it for IPv6 but v6 is manually validated). Reviewed-by: Eric Dumazet <edumazet@google.com> Fixes: 3e7013ddf55a ("tcp: metrics: Allow selective get/del of tcp-metrics based on src IP") Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2024-06-28UPSTREAM: tcp: fix DSACK undo in fast recovery to call tcp_try_to_open()Neal Cardwell
In some production workloads we noticed that connections could sometimes close extremely prematurely with ETIMEDOUT after transmitting only 1 TLP and RTO retransmission (when we would normally expect roughly tcp_retries2 = TCP_RETR2 = 15 RTOs before a connection closes with ETIMEDOUT). From tracing we determined that these workloads can suffer from a scenario where in fast recovery, after some retransmits, a DSACK undo can happen at a point where the scoreboard is totally clear (we have retrans_out == sacked_out == lost_out == 0). In such cases, calling tcp_try_keep_open() means that we do not execute any code path that clears tp->retrans_stamp to 0. That means that tp->retrans_stamp can remain erroneously set to the start time of the undone fast recovery, even after the fast recovery is undone. If minutes or hours elapse, and then a TLP/RTO/RTO sequence occurs, then the start_ts value in retransmits_timed_out() (which is from tp->retrans_stamp) will be erroneously ancient (left over from the fast recovery undone via DSACKs). Thus this ancient tp->retrans_stamp value can cause the connection to die very prematurely with ETIMEDOUT via tcp_write_err(). The fix: we change DSACK undo in fast recovery (TCP_CA_Recovery) to call tcp_try_to_open() instead of tcp_try_keep_open(). This ensures that if no retransmits are in flight at the time of DSACK undo in fast recovery then we properly zero retrans_stamp. Note that calling tcp_try_to_open() is more consistent with other loss recovery behavior, since normal fast recovery (CA_Recovery) and RTO recovery (CA_Loss) both normally end when tp->snd_una meets or exceeds tp->high_seq and then in tcp_fastretrans_alert() the "default" switch case executes tcp_try_to_open(). Also note that by inspection this change to call tcp_try_to_open() implies at least one other nice bug fix, where now an ECE-marked DSACK that causes an undo will properly invoke tcp_enter_cwr() rather than ignoring the ECE mark. Fixes: c7d9d6a185a7 ("tcp: undo on DSACK during recovery") Signed-off-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: Yuchung Cheng <ycheng@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2024-06-25tcp: fix tcp_rcv_fastopen_synack() to enter TCP_CA_Loss for failed TFONeal Cardwell
Testing determined that the recent commit 9e046bb111f1 ("tcp: clear tp->retrans_stamp in tcp_rcv_fastopen_synack()") has a race, and does not always ensure retrans_stamp is 0 after a TFO payload retransmit. If transmit completion for the SYN+data skb happens after the client TCP stack receives the SYNACK (which sometimes happens), then retrans_stamp can erroneously remain non-zero for the lifetime of the connection, causing a premature ETIMEDOUT later. Testing and tracing showed that the buggy scenario is the following somewhat tricky sequence: + Client attempts a TFO handshake. tcp_send_syn_data() sends SYN + TFO cookie + data in a single packet in the syn_data skb. It hands the syn_data skb to tcp_transmit_skb(), which makes a clone. Crucially, it then reuses the same original (non-clone) syn_data skb, transforming it by advancing the seq by one byte and removing the FIN bit, and enques the resulting payload-only skb in the sk->tcp_rtx_queue. + Client sets retrans_stamp to the start time of the three-way handshake. + Cookie mismatches or server has TFO disabled, and server only ACKs SYN. + tcp_ack() sees SYN is acked, tcp_clean_rtx_queue() clears retrans_stamp. + Since the client SYN was acked but not the payload, the TFO failure code path in tcp_rcv_fastopen_synack() tries to retransmit the payload skb. However, in some cases the transmit completion for the clone of the syn_data (which had SYN + TFO cookie + data) hasn't happened. In those cases, skb_still_in_host_queue() returns true for the retransmitted TFO payload, because the clone of the syn_data skb has not had its tx completetion. + Because skb_still_in_host_queue() finds skb_fclone_busy() is true, it sets the TSQ_THROTTLED bit and the retransmit does not happen in the tcp_rcv_fastopen_synack() call chain. + The tcp_rcv_fastopen_synack() code next implicitly assumes the retransmit process is finished, and sets retrans_stamp to 0 to clear it, but this is later overwritten (see below). + Later, upon tx completion, tcp_tsq_write() calls tcp_xmit_retransmit_queue(), which puts the retransmit in flight and sets retrans_stamp to a non-zero value. + The client receives an ACK for the retransmitted TFO payload data. + Since we're in CA_Open and there are no dupacks/SACKs/DSACKs/ECN to make tcp_ack_is_dubious() true and make us call tcp_fastretrans_alert() and reach a code path that clears retrans_stamp, retrans_stamp stays nonzero. + Later, if there is a TLP, RTO, RTO sequence, then the connection will suffer an early ETIMEDOUT due to the erroneously ancient retrans_stamp. The fix: this commit refactors the code to have tcp_rcv_fastopen_synack() retransmit by reusing the relevant parts of tcp_simple_retransmit() that enter CA_Loss (without changing cwnd) and call tcp_xmit_retransmit_queue(). We have tcp_simple_retransmit() and tcp_rcv_fastopen_synack() share code in this way because in both cases we get a packet indicating non-congestion loss (MTU reduction or TFO failure) and thus in both cases we want to retransmit as many packets as cwnd allows, without reducing cwnd. And given that retransmits will set retrans_stamp to a non-zero value (and may do so in a later calling context due to TSQ), we also want to enter CA_Loss so that we track when all retransmitted packets are ACked and clear retrans_stamp when that happens (to ensure later recurring RTOs are using the correct retrans_stamp and don't declare ETIMEDOUT prematurely). Fixes: 9e046bb111f1 ("tcp: clear tp->retrans_stamp in tcp_rcv_fastopen_synack()") Fixes: a7abf3cd76e1 ("tcp: consider using standard rtx logic in tcp_rcv_fastopen_synack()") Signed-off-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Yuchung Cheng <ycheng@google.com> Link: https://patch.msgid.link/20240624144323.2371403-1-ncardwell.sw@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-06-25Fix race for duplicate reqsk on identical SYNluoxuanqiang
When bonding is configured in BOND_MODE_BROADCAST mode, if two identical SYN packets are received at the same time and processed on different CPUs, it can potentially create the same sk (sock) but two different reqsk (request_sock) in tcp_conn_request(). These two different reqsk will respond with two SYNACK packets, and since the generation of the seq (ISN) incorporates a timestamp, the final two SYNACK packets will have different seq values. The consequence is that when the Client receives and replies with an ACK to the earlier SYNACK packet, we will reset(RST) it. ======================================================================== This behavior is consistently reproducible in my local setup, which comprises: | NETA1 ------ NETB1 | PC_A --- bond --- | | --- bond --- PC_B | NETA2 ------ NETB2 | - PC_A is the Server and has two network cards, NETA1 and NETA2. I have bonded these two cards using BOND_MODE_BROADCAST mode and configured them to be handled by different CPU. - PC_B is the Client, also equipped with two network cards, NETB1 and NETB2, which are also bonded and configured in BOND_MODE_BROADCAST mode. If the client attempts a TCP connection to the server, it might encounter a failure. Capturing packets from the server side reveals: 10.10.10.10.45182 > localhost: Flags [S], seq 320236027, 10.10.10.10.45182 > localhost: Flags [S], seq 320236027, localhost > 10.10.10.10.45182: Flags [S.], seq 2967855116, localhost > 10.10.10.10.45182: Flags [S.], seq 2967855123, <== 10.10.10.10.45182 > localhost: Flags [.], ack 4294967290, 10.10.10.10.45182 > localhost: Flags [.], ack 4294967290, localhost > 10.10.10.10.45182: Flags [R], seq 2967855117, <== localhost > 10.10.10.10.45182: Flags [R], seq 2967855117, Two SYNACKs with different seq numbers are sent by localhost, resulting in an anomaly. ======================================================================== The attempted solution is as follows: Add a return value to inet_csk_reqsk_queue_hash_add() to confirm if the ehash insertion is successful (Up to now, the reason for unsuccessful insertion is that a reqsk for the same connection has already been inserted). If the insertion fails, release the reqsk. Due to the refcnt, Kuniyuki suggests also adding a return value check for the DCCP module; if ehash insertion fails, indicating a successful insertion of the same connection, simply release the reqsk as well. Simultaneously, In the reqsk_queue_hash_req(), the start of the req->rsk_timer is adjusted to be after successful insertion. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: luoxuanqiang <luoxuanqiang@kylinos.cn> Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Link: https://lore.kernel.org/r/20240621013929.1386815-1-luoxuanqiang@kylinos.cn Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2024-06-19net/tcp_ao: Don't leak ao_info on error-pathDmitry Safonov
It seems I introduced it together with TCP_AO_CMDF_AO_REQUIRED, on version 5 [1] of TCP-AO patches. Quite frustrative that having all these selftests that I've written, running kmemtest & kcov was always in todo. [1]: https://lore.kernel.org/netdev/20230215183335.800122-5-dima@arista.com/ Reported-by: Jakub Kicinski <kuba@kernel.org> Closes: https://lore.kernel.org/netdev/20240617072451.1403e1d2@kernel.org/ Fixes: 0aadc73995d0 ("net/tcp: Prevent TCP-MD5 with TCP-AO being set") Cc: stable@vger.kernel.org Signed-off-by: Dmitry Safonov <0x7f454c46@gmail.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Link: https://lore.kernel.org/r/20240619-tcp-ao-required-leak-v1-1-6408f3c94247@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-06-17tcp: clear tp->retrans_stamp in tcp_rcv_fastopen_synack()Eric Dumazet
Some applications were reporting ETIMEDOUT errors on apparently good looking flows, according to packet dumps. We were able to root cause the issue to an accidental setting of tp->retrans_stamp in the following scenario: - client sends TFO SYN with data. - server has TFO disabled, ACKs only SYN but not payload. - client receives SYNACK covering only SYN. - tcp_ack() eats SYN and sets tp->retrans_stamp to 0. - tcp_rcv_fastopen_synack() calls tcp_xmit_retransmit_queue() to retransmit TFO payload w/o SYN, sets tp->retrans_stamp to "now", but we are not in any loss recovery state. - TFO payload is ACKed. - we are not in any loss recovery state, and don't see any dupacks, so we don't get to any code path that clears tp->retrans_stamp. - tp->retrans_stamp stays non-zero for the lifetime of the connection. - after first RTO, tcp_clamp_rto_to_user_timeout() clamps second RTO to 1 jiffy due to bogus tp->retrans_stamp. - on clamped RTO with non-zero icsk_retransmits, retransmits_timed_out() sets start_ts from tp->retrans_stamp from TFO payload retransmit hours/days ago, and computes bogus long elapsed time for loss recovery, and suffers ETIMEDOUT early. Fixes: a7abf3cd76e1 ("tcp: consider using standard rtx logic in tcp_rcv_fastopen_synack()") CC: stable@vger.kernel.org Co-developed-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: Neal Cardwell <ncardwell@google.com> Co-developed-by: Yuchung Cheng <ycheng@google.com> Signed-off-by: Yuchung Cheng <ycheng@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Link: https://lore.kernel.org/r/20240614130615.396837-1-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-06-14cipso: make cipso_v4_skbuff_delattr() fully remove the CIPSO optionsOndrej Mosnacek
As the comment in this function says, the code currently just clears the CIPSO part with IPOPT_NOP, rather than removing it completely and trimming the packet. The other cipso_v4_*_delattr() functions, however, do the proper removal and also calipso_skbuff_delattr() makes an effort to remove the CALIPSO options instead of replacing them with padding. Some routers treat IPv4 packets with anything (even NOPs) in the option header as a special case and take them through a slower processing path. Consequently, hardening guides such as STIG recommend to configure such routers to drop packets with non-empty IP option headers [1][2]. Thus, users might expect NetLabel to produce packets with minimal padding (or at least with no padding when no actual options are present). Implement the proper option removal to address this and to be closer to what the peer functions do. [1] https://www.stigviewer.com/stig/juniper_router_rtr/2019-09-27/finding/V-90937 [2] https://www.stigviewer.com/stig/cisco_ios_xe_router_rtr/2021-03-26/finding/V-217001 Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2024-06-14cipso: fix total option length computationOndrej Mosnacek
As evident from the definition of ip_options_get(), the IP option IPOPT_END is used to pad the IP option data array, not IPOPT_NOP. Yet the loop that walks the IP options to determine the total IP options length in cipso_v4_delopt() doesn't take IPOPT_END into account. Fix it by recognizing the IPOPT_END value as the end of actual options. Fixes: 014ab19a69c3 ("selinux: Set socket NetLabel based on connection endpoint") Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2024-06-10tcp: use signed arithmetic in tcp_rtx_probe0_timed_out()Eric Dumazet
Due to timer wheel implementation, a timer will usually fire after its schedule. For instance, for HZ=1000, a timeout between 512ms and 4s has a granularity of 64ms. For this range of values, the extra delay could be up to 63ms. For TCP, this means that tp->rcv_tstamp may be after inet_csk(sk)->icsk_timeout whenever the timer interrupt finally triggers, if one packet came during the extra delay. We need to make sure tcp_rtx_probe0_timed_out() handles this case. Fixes: e89688e3e978 ("net: tcp: fix unexcepted socket die when snd_wnd is 0") Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Menglong Dong <imagedong@tencent.com> Acked-by: Neal Cardwell <ncardwell@google.com> Reviewed-by: Jason Xing <kerneljasonxing@gmail.com> Link: https://lore.kernel.org/r/20240607125652.1472540-1-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-06-05rtnetlink: make the "split" NLM_DONE handling genericJakub Kicinski
Jaroslav reports Dell's OMSA Systems Management Data Engine expects NLM_DONE in a separate recvmsg(), both for rtnl_dump_ifinfo() and inet_dump_ifaddr(). We already added a similar fix previously in commit 460b0d33cf10 ("inet: bring NLM_DONE out to a separate recv() again") Instead of modifying all the dump handlers, and making them look different than modern for_each_netdev_dump()-based dump handlers - put the workaround in rtnetlink code. This will also help us move the custom rtnl-locking from af_netlink in the future (in net-next). Note that this change is not touching rtnl_dump_all(). rtnl_dump_all() is different kettle of fish and a potential problem. We now mix families in a single recvmsg(), but NLM_DONE is not coalesced. Tested: ./cli.py --dbg-small-recv 4096 --spec netlink/specs/rt_addr.yaml \ --dump getaddr --json '{"ifa-family": 2}' ./cli.py --dbg-small-recv 4096 --spec netlink/specs/rt_route.yaml \ --dump getroute --json '{"rtm-family": 2}' ./cli.py --dbg-small-recv 4096 --spec netlink/specs/rt_link.yaml \ --dump getlink Fixes: 3e41af90767d ("rtnetlink: use xarray iterator to implement rtnl_dump_ifinfo()") Fixes: cdb2f80f1c10 ("inet: use xa_array iterator to implement inet_dump_ifaddr()") Reported-by: Jaroslav Pulchart <jaroslav.pulchart@gooddata.com> Link: https://lore.kernel.org/all/CAK8fFZ7MKoFSEzMBDAOjoUt+vTZRRQgLDNXEOfdCCXSoXXKE0g@mail.gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2024-06-05tcp: count CLOSE-WAIT sockets for TCP_MIB_CURRESTABJason Xing
According to RFC 1213, we should also take CLOSE-WAIT sockets into consideration: "tcpCurrEstab OBJECT-TYPE ... The number of TCP connections for which the current state is either ESTABLISHED or CLOSE- WAIT." After this, CurrEstab counter will display the total number of ESTABLISHED and CLOSE-WAIT sockets. The logic of counting When we increment the counter? a) if we change the state to ESTABLISHED. b) if we change the state from SYN-RECEIVED to CLOSE-WAIT. When we decrement the counter? a) if the socket leaves ESTABLISHED and will never go into CLOSE-WAIT, say, on the client side, changing from ESTABLISHED to FIN-WAIT-1. b) if the socket leaves CLOSE-WAIT, say, on the server side, changing from CLOSE-WAIT to LAST-ACK. Please note: there are two chances that old state of socket can be changed to CLOSE-WAIT in tcp_fin(). One is SYN-RECV, the other is ESTABLISHED. So we have to take care of the former case. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Jason Xing <kernelxing@tencent.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2024-06-04net: tls: fix marking packets as decryptedJakub Kicinski
For TLS offload we mark packets with skb->decrypted to make sure they don't escape the host without getting encrypted first. The crypto state lives in the socket, so it may get detached by a call to skb_orphan(). As a safety check - the egress path drops all packets with skb->decrypted and no "crypto-safe" socket. The skb marking was added to sendpage only (and not sendmsg), because tls_device injected data into the TCP stack using sendpage. This special case was missed when sendpage got folded into sendmsg. Fixes: c5c37af6ecad ("tcp: Convert do_tcp_sendpages() to use MSG_SPLICE_PAGES") Signed-off-by: Jakub Kicinski <kuba@kernel.org> Reviewed-by: Eric Dumazet <edumazet@google.com> Link: https://lore.kernel.org/r/20240530232607.82686-1-kuba@kernel.org Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2024-06-01net/tcp: Don't consider TCP_CLOSE in TCP_AO_ESTABLISHEDDmitry Safonov
TCP_CLOSE may or may not have current/rnext keys and should not be considered "established". The fast-path for TCP_CLOSE is SKB_DROP_REASON_TCP_CLOSE. This is what tcp_rcv_state_process() does anyways. Add an early drop path to not spend any time verifying segment signatures for sockets in TCP_CLOSE state. Cc: stable@vger.kernel.org # v6.7 Fixes: 0a3a809089eb ("net/tcp: Verify inbound TCP-AO signed segments") Signed-off-by: Dmitry Safonov <0x7f454c46@gmail.com> Link: https://lore.kernel.org/r/20240529-tcp_ao-sk_state-v1-1-d69b5d323c52@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-05-30Merge tag 'nf-24-05-29' of ↵Paolo Abeni
git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf Pablo Neira Ayuso says: ==================== Netfilter fixes for net The following patchset contains Netfilter fixes for net: Patch #1 syzbot reports that nf_reinject() could be called without rcu_read_lock() when flushing pending packets at nfnetlink queue removal, from Eric Dumazet. Patch #2 flushes ipset list:set when canceling garbage collection to reference to other lists to fix a race, from Jozsef Kadlecsik. Patch #3 restores q-in-q matching with nft_payload by reverting f6ae9f120dad ("netfilter: nft_payload: add C-VLAN support"). Patch #4 fixes vlan mangling in skbuff when vlan offload is present in skbuff, without this patch nft_payload corrupts packets in this case. Patch #5 fixes possible nul-deref in tproxy no IP address is found in netdevice, reported by syzbot and patch from Florian Westphal. Patch #6 removes a superfluous restriction which prevents loose fib lookups from input and forward hooks, from Eric Garver. My assessment is that patches #1, #2 and #5 address possible kernel crash, anything else in this batch fixes broken features. netfilter pull request 24-05-29 * tag 'nf-24-05-29' of git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf: netfilter: nft_fib: allow from forward/input without iif selector netfilter: tproxy: bail out if IP has been disabled on the device netfilter: nft_payload: skbuff vlan metadata mangle support netfilter: nft_payload: restore vlan q-in-q match support netfilter: ipset: Add list flush to cancel_gc netfilter: nfnetlink_queue: acquire rcu_read_lock() in instance_destroy_rcu() ==================== Link: https://lore.kernel.org/r/20240528225519.1155786-1-pablo@netfilter.org Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2024-05-29ipv4: correctly iterate over the target netns in inet_dump_ifaddr()Alexander Mikhalitsyn
A recent change to inet_dump_ifaddr had the function incorrectly iterate over net rather than tgt_net, resulting in the data coming for the incorrect network namespace. Fixes: cdb2f80f1c10 ("inet: use xa_array iterator to implement inet_dump_ifaddr()") Reported-by: Stéphane Graber <stgraber@stgraber.org> Closes: https://github.com/lxc/incus/issues/892 Bisected-by: Stéphane Graber <stgraber@stgraber.org> Signed-off-by: Alexander Mikhalitsyn <aleksandr.mikhalitsyn@canonical.com> Tested-by: Stéphane Graber <stgraber@stgraber.org> Acked-by: Christian Brauner <brauner@kernel.org> Reviewed-by: Eric Dumazet <edumazet@google.com> Link: https://lore.kernel.org/r/20240528203030.10839-1-aleksandr.mikhalitsyn@canonical.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-05-29net: fix __dst_negative_advice() raceEric Dumazet
__dst_negative_advice() does not enforce proper RCU rules when sk->dst_cache must be cleared, leading to possible UAF. RCU rules are that we must first clear sk->sk_dst_cache, then call dst_release(old_dst). Note that sk_dst_reset(sk) is implementing this protocol correctly, while __dst_negative_advice() uses the wrong order. Given that ip6_negative_advice() has special logic against RTF_CACHE, this means each of the three ->negative_advice() existing methods must perform the sk_dst_reset() themselves. Note the check against NULL dst is centralized in __dst_negative_advice(), there is no need to duplicate it in various callbacks. Many thanks to Clement Lecigne for tracking this issue. This old bug became visible after the blamed commit, using UDP sockets. Fixes: a87cb3e48ee8 ("net: Facility to report route quality of connected sockets") Reported-by: Clement Lecigne <clecigne@google.com> Diagnosed-by: Clement Lecigne <clecigne@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Tom Herbert <tom@herbertland.com> Reviewed-by: David Ahern <dsahern@kernel.org> Link: https://lore.kernel.org/r/20240528114353.1794151-1-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-05-29netfilter: tproxy: bail out if IP has been disabled on the deviceFlorian Westphal
syzbot reports: general protection fault, probably for non-canonical address 0xdffffc0000000003: 0000 [#1] PREEMPT SMP KASAN PTI KASAN: null-ptr-deref in range [0x0000000000000018-0x000000000000001f] [..] RIP: 0010:nf_tproxy_laddr4+0xb7/0x340 net/ipv4/netfilter/nf_tproxy_ipv4.c:62 Call Trace: nft_tproxy_eval_v4 net/netfilter/nft_tproxy.c:56 [inline] nft_tproxy_eval+0xa9a/0x1a00 net/netfilter/nft_tproxy.c:168 __in_dev_get_rcu() can return NULL, so check for this. Reported-and-tested-by: syzbot+b94a6818504ea90d7661@syzkaller.appspotmail.com Fixes: cc6eb4338569 ("tproxy: use the interface primary IP address as a default value for --on-ip") Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2024-05-27tcp: reduce accepted window in NEW_SYN_RECV stateEric Dumazet
Jason commit made checks against ACK sequence less strict and can be exploited by attackers to establish spoofed flows with less probes. Innocent users might use tcp_rmem[1] == 1,000,000,000, or something more reasonable. An attacker can use a regular TCP connection to learn the server initial tp->rcv_wnd, and use it to optimize the attack. If we make sure that only the announced window (smaller than 65535) is used for ACK validation, we force an attacker to use 65537 packets to complete the 3WHS (assuming server ISN is unknown) Fixes: 378979e94e95 ("tcp: remove 64 KByte limit for initial tp->rcv_wnd value") Link: https://datatracker.ietf.org/meeting/119/materials/slides-119-tcpm-ghost-acks-00 Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Neal Cardwell <ncardwell@google.com> Reviewed-by: Jason Xing <kerneljasonxing@gmail.com> Link: https://lore.kernel.org/r/20240523130528.60376-1-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-05-27net: gro: initialize network_offset in network layerWillem de Bruijn
Syzkaller was able to trigger kernel BUG at net/core/gro.c:424 ! RIP: 0010:gro_pull_from_frag0 net/core/gro.c:424 [inline] RIP: 0010:gro_try_pull_from_frag0 net/core/gro.c:446 [inline] RIP: 0010:dev_gro_receive+0x242f/0x24b0 net/core/gro.c:571 Due to using an incorrect NAPI_GRO_CB(skb)->network_offset. The referenced commit sets this offset to 0 in skb_gro_reset_offset. That matches the expected case in dev_gro_receive: pp = INDIRECT_CALL_INET(ptype->callbacks.gro_receive, ipv6_gro_receive, inet_gro_receive, &gro_list->list, skb); But syzkaller injected an skb with protocol ETH_P_TEB into an ip6gre device (by writing the IP6GRE encapsulated version to a TAP device). The result was a first call to eth_gro_receive, and thus an extra ETH_HLEN in network_offset that should not be there. First issue hit is when computing offset from network header in ipv6_gro_pull_exthdrs. Initialize both offsets in the network layer gro_receive. This pairs with all reads in gro_receive, which use skb_gro_receive_network_offset(). Fixes: 186b1ea73ad8 ("net: gro: use cb instead of skb->network_header") Reported-by: syzkaller <syzkaller@googlegroups.com> Signed-off-by: Willem de Bruijn <willemb@google.com> CC: Richard Gobert <richardbgobert@gmail.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Link: https://lore.kernel.org/r/20240523141434.1752483-1-willemdebruijn.kernel@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-05-27ipv4: Fix address dump when IPv4 is disabled on an interfaceIdo Schimmel
Cited commit started returning an error when user space requests to dump the interface's IPv4 addresses and IPv4 is disabled on the interface. Restore the previous behavior and do not return an error. Before cited commit: # ip address show dev dummy1 10: dummy1: <BROADCAST,NOARP,UP,LOWER_UP> mtu 1500 qdisc noqueue state UNKNOWN group default qlen 1000 link/ether e2:40:68:98:d0:18 brd ff:ff:ff:ff:ff:ff inet6 fe80::e040:68ff:fe98:d018/64 scope link proto kernel_ll valid_lft forever preferred_lft forever # ip link set dev dummy1 mtu 67 # ip address show dev dummy1 10: dummy1: <BROADCAST,NOARP,UP,LOWER_UP> mtu 67 qdisc noqueue state UNKNOWN group default qlen 1000 link/ether e2:40:68:98:d0:18 brd ff:ff:ff:ff:ff:ff After cited commit: # ip address show dev dummy1 10: dummy1: <BROADCAST,NOARP,UP,LOWER_UP> mtu 1500 qdisc noqueue state UNKNOWN group default qlen 1000 link/ether 32:2d:69:f2:9c:99 brd ff:ff:ff:ff:ff:ff inet6 fe80::302d:69ff:fef2:9c99/64 scope link proto kernel_ll valid_lft forever preferred_lft forever # ip link set dev dummy1 mtu 67 # ip address show dev dummy1 RTNETLINK answers: No such device Dump terminated With this patch: # ip address show dev dummy1 10: dummy1: <BROADCAST,NOARP,UP,LOWER_UP> mtu 1500 qdisc noqueue state UNKNOWN group default qlen 1000 link/ether de:17:56:bb:57:c0 brd ff:ff:ff:ff:ff:ff inet6 fe80::dc17:56ff:febb:57c0/64 scope link proto kernel_ll valid_lft forever preferred_lft forever # ip link set dev dummy1 mtu 67 # ip address show dev dummy1 10: dummy1: <BROADCAST,NOARP,UP,LOWER_UP> mtu 67 qdisc noqueue state UNKNOWN group default qlen 1000 link/ether de:17:56:bb:57:c0 brd ff:ff:ff:ff:ff:ff I fixed the exact same issue for IPv6 in commit c04f7dfe6ec2 ("ipv6: Fix address dump when IPv6 is disabled on an interface"), but noted [1] that I am not doing the change for IPv4 because I am not aware of a way to disable IPv4 on an interface other than unregistering it. I clearly missed the above case. [1] https://lore.kernel.org/netdev/20240321173042.2151756-1-idosch@nvidia.com/ Fixes: cdb2f80f1c10 ("inet: use xa_array iterator to implement inet_dump_ifaddr()") Reported-by: Carolina Jubran <cjubran@nvidia.com> Reported-by: Yamen Safadi <ysafadi@nvidia.com> Tested-by: Carolina Jubran <cjubran@nvidia.com> Reviewed-by: Petr Machata <petrm@nvidia.com> Signed-off-by: Ido Schimmel <idosch@nvidia.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Reviewed-by: David Ahern <dsahern@kernel.org> Link: https://lore.kernel.org/r/20240523110257.334315-1-idosch@nvidia.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-05-23Merge tag 'net-6.10-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net Pull networking fixes from Paolo Abeni: "Quite smaller than usual. Notably it includes the fix for the unix regression from the past weeks. The TCP window fix will require some follow-up, already queued. Current release - regressions: - af_unix: fix garbage collection of embryos Previous releases - regressions: - af_unix: fix race between GC and receive path - ipv6: sr: fix missing sk_buff release in seg6_input_core - tcp: remove 64 KByte limit for initial tp->rcv_wnd value - eth: r8169: fix rx hangup - eth: lan966x: remove ptp traps in case the ptp is not enabled - eth: ixgbe: fix link breakage vs cisco switches - eth: ice: prevent ethtool from corrupting the channels Previous releases - always broken: - openvswitch: set the skbuff pkt_type for proper pmtud support - tcp: Fix shift-out-of-bounds in dctcp_update_alpha() Misc: - a bunch of selftests stabilization patches" * tag 'net-6.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (25 commits) r8169: Fix possible ring buffer corruption on fragmented Tx packets. idpf: Interpret .set_channels() input differently ice: Interpret .set_channels() input differently nfc: nci: Fix handling of zero-length payload packets in nci_rx_work() net: relax socket state check at accept time. tcp: remove 64 KByte limit for initial tp->rcv_wnd value net: ti: icssg_prueth: Fix NULL pointer dereference in prueth_probe() tls: fix missing memory barrier in tls_init net: fec: avoid lock evasion when reading pps_enable Revert "ixgbe: Manual AN-37 for troublesome link partners for X550 SFI" testing: net-drv: use stats64 for testing net: mana: Fix the extra HZ in mana_hwc_send_request net: lan966x: Remove ptp traps in case the ptp is not enabled. openvswitch: Set the skbuff pkt_type for proper pmtud support. selftest: af_unix: Make SCM_RIGHTS into OOB data. af_unix: Fix garbage collection of embryos carrying OOB with SCM_RIGHTS tcp: Fix shift-out-of-bounds in dctcp_update_alpha(). selftests/net: use tc rule to filter the na packet ipv6: sr: fix memleak in seg6_hmac_init_algo af_unix: Update unix_sk(sk)->oob_skb under sk_receive_queue lock. ...
2024-05-23net: relax socket state check at accept time.Paolo Abeni
Christoph reported the following splat: WARNING: CPU: 1 PID: 772 at net/ipv4/af_inet.c:761 __inet_accept+0x1f4/0x4a0 Modules linked in: CPU: 1 PID: 772 Comm: syz-executor510 Not tainted 6.9.0-rc7-g7da7119fe22b #56 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.11.0-2.el7 04/01/2014 RIP: 0010:__inet_accept+0x1f4/0x4a0 net/ipv4/af_inet.c:759 Code: 04 38 84 c0 0f 85 87 00 00 00 41 c7 04 24 03 00 00 00 48 83 c4 10 5b 41 5c 41 5d 41 5e 41 5f 5d c3 cc cc cc cc e8 ec b7 da fd <0f> 0b e9 7f fe ff ff e8 e0 b7 da fd 0f 0b e9 fe fe ff ff 89 d9 80 RSP: 0018:ffffc90000c2fc58 EFLAGS: 00010293 RAX: ffffffff836bdd14 RBX: 0000000000000000 RCX: ffff888104668000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: dffffc0000000000 R08: ffffffff836bdb89 R09: fffff52000185f64 R10: dffffc0000000000 R11: fffff52000185f64 R12: dffffc0000000000 R13: 1ffff92000185f98 R14: ffff88810754d880 R15: ffff8881007b7800 FS: 000000001c772880(0000) GS:ffff88811b280000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fb9fcf2e178 CR3: 00000001045d2002 CR4: 0000000000770ef0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 PKRU: 55555554 Call Trace: <TASK> inet_accept+0x138/0x1d0 net/ipv4/af_inet.c:786 do_accept+0x435/0x620 net/socket.c:1929 __sys_accept4_file net/socket.c:1969 [inline] __sys_accept4+0x9b/0x110 net/socket.c:1999 __do_sys_accept net/socket.c:2016 [inline] __se_sys_accept net/socket.c:2013 [inline] __x64_sys_accept+0x7d/0x90 net/socket.c:2013 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0x58/0x100 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x76/0x7e RIP: 0033:0x4315f9 Code: fd ff 48 81 c4 80 00 00 00 e9 f1 fe ff ff 0f 1f 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 0f 83 ab b4 fd ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007ffdb26d9c78 EFLAGS: 00000246 ORIG_RAX: 000000000000002b RAX: ffffffffffffffda RBX: 0000000000400300 RCX: 00000000004315f9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000004 RBP: 00000000006e1018 R08: 0000000000400300 R09: 0000000000400300 R10: 0000000000400300 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000040cdf0 R14: 000000000040ce80 R15: 0000000000000055 </TASK> The reproducer invokes shutdown() before entering the listener status. After commit 94062790aedb ("tcp: defer shutdown(SEND_SHUTDOWN) for TCP_SYN_RECV sockets"), the above causes the child to reach the accept syscall in FIN_WAIT1 status. Eric noted we can relax the existing assertion in __inet_accept() Reported-by: Christoph Paasch <cpaasch@apple.com> Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/490 Suggested-by: Eric Dumazet <edumazet@google.com> Fixes: 94062790aedb ("tcp: defer shutdown(SEND_SHUTDOWN) for TCP_SYN_RECV sockets") Reviewed-by: Eric Dumazet <edumazet@google.com> Link: https://lore.kernel.org/r/23ab880a44d8cfd967e84de8b93dbf48848e3d8c.1716299669.git.pabeni@redhat.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2024-05-23tcp: remove 64 KByte limit for initial tp->rcv_wnd valueJason Xing
Recently, we had some servers upgraded to the latest kernel and noticed the indicator from the user side showed worse results than before. It is caused by the limitation of tp->rcv_wnd. In 2018 commit a337531b942b ("tcp: up initial rmem to 128KB and SYN rwin to around 64KB") limited the initial value of tp->rcv_wnd to 65535, most CDN teams would not benefit from this change because they cannot have a large window to receive a big packet, which will be slowed down especially in long RTT. Small rcv_wnd means slow transfer speed, to some extent. It's the side effect for the latency/time-sensitive users. To avoid future confusion, current change doesn't affect the initial receive window on the wire in a SYN or SYN+ACK packet which are set within 65535 bytes according to RFC 7323 also due to the limit in __tcp_transmit_skb(): th->window = htons(min(tp->rcv_wnd, 65535U)); In one word, __tcp_transmit_skb() already ensures that constraint is respected, no matter how large tp->rcv_wnd is. The change doesn't violate RFC. Let me provide one example if with or without the patch: Before: client --- SYN: rwindow=65535 ---> server client <--- SYN+ACK: rwindow=65535 ---- server client --- ACK: rwindow=65536 ---> server Note: for the last ACK, the calculation is 512 << 7. After: client --- SYN: rwindow=65535 ---> server client <--- SYN+ACK: rwindow=65535 ---- server client --- ACK: rwindow=175232 ---> server Note: I use the following command to make it work: ip route change default via [ip] dev eth0 metric 100 initrwnd 120 For the last ACK, the calculation is 1369 << 7. When we apply such a patch, having a large rcv_wnd if the user tweak this knob can help transfer data more rapidly and save some rtts. Fixes: a337531b942b ("tcp: up initial rmem to 128KB and SYN rwin to around 64KB") Signed-off-by: Jason Xing <kernelxing@tencent.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Acked-by: Neal Cardwell <ncardwell@google.com> Link: https://lore.kernel.org/r/20240521134220.12510-1-kerneljasonxing@gmail.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2024-05-21tcp: Fix shift-out-of-bounds in dctcp_update_alpha().Kuniyuki Iwashima
In dctcp_update_alpha(), we use a module parameter dctcp_shift_g as follows: alpha -= min_not_zero(alpha, alpha >> dctcp_shift_g); ... delivered_ce <<= (10 - dctcp_shift_g); It seems syzkaller started fuzzing module parameters and triggered shift-out-of-bounds [0] by setting 100 to dctcp_shift_g: memcpy((void*)0x20000080, "/sys/module/tcp_dctcp/parameters/dctcp_shift_g\000", 47); res = syscall(__NR_openat, /*fd=*/0xffffffffffffff9cul, /*file=*/0x20000080ul, /*flags=*/2ul, /*mode=*/0ul); memcpy((void*)0x20000000, "100\000", 4); syscall(__NR_write, /*fd=*/r[0], /*val=*/0x20000000ul, /*len=*/4ul); Let's limit the max value of dctcp_shift_g by param_set_uint_minmax(). With this patch: # echo 10 > /sys/module/tcp_dctcp/parameters/dctcp_shift_g # cat /sys/module/tcp_dctcp/parameters/dctcp_shift_g 10 # echo 11 > /sys/module/tcp_dctcp/parameters/dctcp_shift_g -bash: echo: write error: Invalid argument [0]: UBSAN: shift-out-of-bounds in net/ipv4/tcp_dctcp.c:143:12 shift exponent 100 is too large for 32-bit type 'u32' (aka 'unsigned int') CPU: 0 PID: 8083 Comm: syz-executor345 Not tainted 6.9.0-05151-g1b294a1f3561 #2 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.13.0-1ubuntu1.1 04/01/2014 Call Trace: <TASK> __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x201/0x300 lib/dump_stack.c:114 ubsan_epilogue lib/ubsan.c:231 [inline] __ubsan_handle_shift_out_of_bounds+0x346/0x3a0 lib/ubsan.c:468 dctcp_update_alpha+0x540/0x570 net/ipv4/tcp_dctcp.c:143 tcp_in_ack_event net/ipv4/tcp_input.c:3802 [inline] tcp_ack+0x17b1/0x3bc0 net/ipv4/tcp_input.c:3948 tcp_rcv_state_process+0x57a/0x2290 net/ipv4/tcp_input.c:6711 tcp_v4_do_rcv+0x764/0xc40 net/ipv4/tcp_ipv4.c:1937 sk_backlog_rcv include/net/sock.h:1106 [inline] __release_sock+0x20f/0x350 net/core/sock.c:2983 release_sock+0x61/0x1f0 net/core/sock.c:3549 mptcp_subflow_shutdown+0x3d0/0x620 net/mptcp/protocol.c:2907 mptcp_check_send_data_fin+0x225/0x410 net/mptcp/protocol.c:2976 __mptcp_close+0x238/0xad0 net/mptcp/protocol.c:3072 mptcp_close+0x2a/0x1a0 net/mptcp/protocol.c:3127 inet_release+0x190/0x1f0 net/ipv4/af_inet.c:437 __sock_release net/socket.c:659 [inline] sock_close+0xc0/0x240 net/socket.c:1421 __fput+0x41b/0x890 fs/file_table.c:422 task_work_run+0x23b/0x300 kernel/task_work.c:180 exit_task_work include/linux/task_work.h:38 [inline] do_exit+0x9c8/0x2540 kernel/exit.c:878 do_group_exit+0x201/0x2b0 kernel/exit.c:1027 __do_sys_exit_group kernel/exit.c:1038 [inline] __se_sys_exit_group kernel/exit.c:1036 [inline] __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1036 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xe4/0x240 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x67/0x6f RIP: 0033:0x7f6c2b5005b6 Code: Unable to access opcode bytes at 0x7f6c2b50058c. RSP: 002b:00007ffe883eb948 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 RAX: ffffffffffffffda RBX: 00007f6c2b5862f0 RCX: 00007f6c2b5005b6 RDX: 0000000000000001 RSI: 000000000000003c RDI: 0000000000000001 RBP: 0000000000000001 R08: 00000000000000e7 R09: ffffffffffffffc0 R10: 0000000000000006 R11: 0000000000000246 R12: 00007f6c2b5862f0 R13: 0000000000000001 R14: 0000000000000000 R15: 0000000000000001 </TASK> Reported-by: syzkaller <syzkaller@googlegroups.com> Reported-by: Yue Sun <samsun1006219@gmail.com> Reported-by: xingwei lee <xrivendell7@gmail.com> Closes: https://lore.kernel.org/netdev/CAEkJfYNJM=cw-8x7_Vmj1J6uYVCWMbbvD=EFmDPVBGpTsqOxEA@mail.gmail.com/ Fixes: e3118e8359bb ("net: tcp: add DCTCP congestion control algorithm") Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Reviewed-by: Simon Horman <horms@kernel.org> Link: https://lore.kernel.org/r/20240517091626.32772-1-kuniyu@amazon.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2024-05-18Merge tag 'net-accept-more-20240515' of git://git.kernel.dk/linuxLinus Torvalds
Pull more io_uring updates from Jens Axboe: "This adds support for IORING_CQE_F_SOCK_NONEMPTY for io_uring accept requests. This is very similar to previous work that enabled the same hint for doing receives on sockets. By far the majority of the work here is refactoring to enable the networking side to pass back whether or not the socket had more pending requests after accepting the current one, the last patch just wires it up for io_uring. Not only does this enable applications to know whether there are more connections to accept right now, it also enables smarter logic for io_uring multishot accept on whether to retry immediately or wait for a poll trigger" * tag 'net-accept-more-20240515' of git://git.kernel.dk/linux: io_uring/net: wire up IORING_CQE_F_SOCK_NONEMPTY for accept net: pass back whether socket was empty post accept net: have do_accept() take a struct proto_accept_arg argument net: change proto and proto_ops accept type
2024-05-14Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski
Merge in late fixes to prepare for the 6.10 net-next PR. Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-05-13tcp: rstreason: fully support in tcp_check_req()Jason Xing
We're going to send an RST due to invalid syn packet which is already checked whether 1) it is in sequence, 2) it is a retransmitted skb. As RFC 793 says, if the state of socket is not CLOSED/LISTEN/SYN-SENT, then we should send an RST when receiving bad syn packet: "fourth, check the SYN bit,...If the SYN is in the window it is an error, send a reset" Signed-off-by: Jason Xing <kernelxing@tencent.com> Link: https://lore.kernel.org/r/20240510122502.27850-6-kerneljasonxing@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-05-13tcp: rstreason: handle timewait cases in the receive pathJason Xing
There are two possible cases where TCP layer can send an RST. Since they happen in the same place, I think using one independent reason is enough to identify this special situation. Signed-off-by: Jason Xing <kernelxing@tencent.com> Link: https://lore.kernel.org/r/20240510122502.27850-5-kerneljasonxing@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-05-13net: pass back whether socket was empty post acceptJens Axboe
This adds an 'is_empty' argument to struct proto_accept_arg, which can be used to pass back information on whether or not the given socket has more connections to accept post the one just accepted. To utilize this information, the caller should initialize the 'is_empty' field to, eg, -1 and then check for 0/1 after the accept. If the field has been set, the caller knows whether there are more pending connections or not. If the field remains -1 after the accept call, the protocol doesn't support passing back this information. This patch wires it up for ipv4/6 TCP. Acked-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-05-13net: change proto and proto_ops accept typeJens Axboe
Rather than pass in flags, error pointer, and whether this is a kernel invocation or not, add a struct proto_accept_arg struct as the argument. This then holds all of these arguments, and prepares accept for being able to pass back more information. No functional changes in this patch. Acked-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2024-05-13Merge tag 'for-netdev' of ↵Jakub Kicinski
https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next Daniel Borkmann says: ==================== pull-request: bpf-next 2024-05-13 We've added 119 non-merge commits during the last 14 day(s) which contain a total of 134 files changed, 9462 insertions(+), 4742 deletions(-). The main changes are: 1) Add BPF JIT support for 32-bit ARCv2 processors, from Shahab Vahedi. 2) Add BPF range computation improvements to the verifier in particular around XOR and OR operators, refactoring of checks for range computation and relaxing MUL range computation so that src_reg can also be an unknown scalar, from Cupertino Miranda. 3) Add support to attach kprobe BPF programs through kprobe_multi link in a session mode, meaning, a BPF program is attached to both function entry and return, the entry program can decide if the return program gets executed and the entry program can share u64 cookie value with return program. Session mode is a common use-case for tetragon and bpftrace, from Jiri Olsa. 4) Fix a potential overflow in libbpf's ring__consume_n() and improve libbpf as well as BPF selftest's struct_ops handling, from Andrii Nakryiko. 5) Improvements to BPF selftests in context of BPF gcc backend, from Jose E. Marchesi & David Faust. 6) Migrate remaining BPF selftest tests from test_sock_addr.c to prog_test- -style in order to retire the old test, run it in BPF CI and additionally expand test coverage, from Jordan Rife. 7) Big batch for BPF selftest refactoring in order to remove duplicate code around common network helpers, from Geliang Tang. 8) Another batch of improvements to BPF selftests to retire obsolete bpf_tcp_helpers.h as everything is available vmlinux.h, from Martin KaFai Lau. 9) Fix BPF map tear-down to not walk the map twice on free when both timer and wq is used, from Benjamin Tissoires. 10) Fix BPF verifier assumptions about socket->sk that it can be non-NULL, from Alexei Starovoitov. 11) Change BTF build scripts to using --btf_features for pahole v1.26+, from Alan Maguire. 12) Small improvements to BPF reusing struct_size() and krealloc_array(), from Andy Shevchenko. 13) Fix s390 JIT to emit a barrier for BPF_FETCH instructions, from Ilya Leoshkevich. 14) Extend TCP ->cong_control() callback in order to feed in ack and flag parameters and allow write-access to tp->snd_cwnd_stamp from BPF program, from Miao Xu. 15) Add support for internal-only per-CPU instructions to inline bpf_get_smp_processor_id() helper call for arm64 and riscv64 BPF JITs, from Puranjay Mohan. 16) Follow-up to remove the redundant ethtool.h from tooling infrastructure, from Tushar Vyavahare. 17) Extend libbpf to support "module:<function>" syntax for tracing programs, from Viktor Malik. * tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (119 commits) bpf: make list_for_each_entry portable bpf: ignore expected GCC warning in test_global_func10.c bpf: disable strict aliasing in test_global_func9.c selftests/bpf: Free strdup memory in xdp_hw_metadata selftests/bpf: Fix a few tests for GCC related warnings. bpf: avoid gcc overflow warning in test_xdp_vlan.c tools: remove redundant ethtool.h from tooling infra selftests/bpf: Expand ATTACH_REJECT tests selftests/bpf: Expand getsockname and getpeername tests sefltests/bpf: Expand sockaddr hook deny tests selftests/bpf: Expand sockaddr program return value tests selftests/bpf: Retire test_sock_addr.(c|sh) selftests/bpf: Remove redundant sendmsg test cases selftests/bpf: Migrate ATTACH_REJECT test cases selftests/bpf: Migrate expected_attach_type tests selftests/bpf: Migrate wildcard destination rewrite test selftests/bpf: Migrate sendmsg6 v4 mapped address tests selftests/bpf: Migrate sendmsg deny test cases selftests/bpf: Migrate WILDCARD_IP test selftests/bpf: Handle SYSCALL_EPERM and SYSCALL_ENOTSUPP test cases ... ==================== Link: https://lore.kernel.org/r/20240513134114.17575-1-daniel@iogearbox.net Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-05-13netlabel: fix RCU annotation for IPv4 options on socket creationDavide Caratti
Xiumei reports the following splat when netlabel and TCP socket are used: ============================= WARNING: suspicious RCU usage 6.9.0-rc2+ #637 Not tainted ----------------------------- net/ipv4/cipso_ipv4.c:1880 suspicious rcu_dereference_protected() usage! other info that might help us debug this: rcu_scheduler_active = 2, debug_locks = 1 1 lock held by ncat/23333: #0: ffffffff906030c0 (rcu_read_lock){....}-{1:2}, at: netlbl_sock_setattr+0x25/0x1b0 stack backtrace: CPU: 11 PID: 23333 Comm: ncat Kdump: loaded Not tainted 6.9.0-rc2+ #637 Hardware name: Supermicro SYS-6027R-72RF/X9DRH-7TF/7F/iTF/iF, BIOS 3.0 07/26/2013 Call Trace: <TASK> dump_stack_lvl+0xa9/0xc0 lockdep_rcu_suspicious+0x117/0x190 cipso_v4_sock_setattr+0x1ab/0x1b0 netlbl_sock_setattr+0x13e/0x1b0 selinux_netlbl_socket_post_create+0x3f/0x80 selinux_socket_post_create+0x1a0/0x460 security_socket_post_create+0x42/0x60 __sock_create+0x342/0x3a0 __sys_socket_create.part.22+0x42/0x70 __sys_socket+0x37/0xb0 __x64_sys_socket+0x16/0x20 do_syscall_64+0x96/0x180 ? do_user_addr_fault+0x68d/0xa30 ? exc_page_fault+0x171/0x280 ? asm_exc_page_fault+0x22/0x30 entry_SYSCALL_64_after_hwframe+0x71/0x79 RIP: 0033:0x7fbc0ca3fc1b Code: 73 01 c3 48 8b 0d 05 f2 1b 00 f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 90 f3 0f 1e fa b8 29 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d d5 f1 1b 00 f7 d8 64 89 01 48 RSP: 002b:00007fff18635208 EFLAGS: 00000246 ORIG_RAX: 0000000000000029 RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 00007fbc0ca3fc1b RDX: 0000000000000006 RSI: 0000000000000001 RDI: 0000000000000002 RBP: 000055d24f80f8a0 R08: 0000000000000003 R09: 0000000000000001 R10: 0000000000020000 R11: 0000000000000246 R12: 000055d24f80f8a0 R13: 0000000000000000 R14: 000055d24f80fb88 R15: 0000000000000000 </TASK> The current implementation of cipso_v4_sock_setattr() replaces IP options under the assumption that the caller holds the socket lock; however, such assumption is not true, nor needed, in selinux_socket_post_create() hook. Let all callers of cipso_v4_sock_setattr() specify the "socket lock held" condition, except selinux_socket_post_create() _ where such condition can safely be set as true even without holding the socket lock. Fixes: f6d8bd051c39 ("inet: add RCU protection to inet->opt") Reported-by: Xiumei Mu <xmu@redhat.com> Signed-off-by: Davide Caratti <dcaratti@redhat.com> Acked-by: Casey Schaufler <casey@schaufler-ca.com> Acked-by: Paul Moore <paul@paul-moore.com> Link: https://lore.kernel.org/r/f4260d000a3a55b9e8b6a3b4e3fffc7da9f82d41.1715359817.git.dcaratti@redhat.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-05-13tcp: socket option to check for MPTCP fallback to TCPMatthieu Baerts (NGI0)
A way for an application to know if an MPTCP connection fell back to TCP is to use getsockopt(MPTCP_INFO) and look for errors. The issue with this technique is that the same errors -- EOPNOTSUPP (IPv4) and ENOPROTOOPT (IPv6) -- are returned if there was a fallback, *or* if the kernel doesn't support this socket option. The userspace then has to look at the kernel version to understand what the errors mean. It is not clean, and it doesn't take into account older kernels where the socket option has been backported. A cleaner way would be to expose this info to the TCP socket level. In case of MPTCP socket where no fallback happened, the socket options for the TCP level will be handled in MPTCP code, in mptcp_getsockopt_sol_tcp(). If not, that will be in TCP code, in do_tcp_getsockopt(). So MPTCP simply has to set the value 1, while TCP has to set 0. If the socket option is not supported, one of these two errors will be reported: - EOPNOTSUPP (95 - Operation not supported) for MPTCP sockets - ENOPROTOOPT (92 - Protocol not available) for TCP sockets, e.g. on the socket received after an 'accept()', when the client didn't request to use MPTCP: this socket will be a TCP one, even if the listen socket was an MPTCP one. With this new option, the kernel can return a clear answer to both "Is this kernel new enough to tell me the fallback status?" and "If it is new enough, is it currently a TCP or MPTCP socket?" questions, while not breaking the previous method. Acked-by: Mat Martineau <martineau@kernel.org> Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org> Link: https://lore.kernel.org/r/20240509-upstream-net-next-20240509-mptcp-tcp_is_mptcp-v1-1-f846df999202@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-05-13net: gro: move L3 flush checks to tcp_gro_receive and udp_gro_receive_segmentRichard Gobert
{inet,ipv6}_gro_receive functions perform flush checks (ttl, flags, iph->id, ...) against all packets in a loop. These flush checks are used in all merging UDP and TCP flows. These checks need to be done only once and only against the found p skb, since they only affect flush and not same_flow. This patch leverages correct network header offsets from the cb for both outer and inner network headers - allowing these checks to be done only once, in tcp_gro_receive and udp_gro_receive_segment. As a result, NAPI_GRO_CB(p)->flush is not used at all. In addition, flush_id checks are more declarative and contained in inet_gro_flush, thus removing the need for flush_id in napi_gro_cb. This results in less parsing code for non-loop flush tests for TCP and UDP flows. To make sure results are not within noise range - I've made netfilter drop all TCP packets, and measured CPU performance in GRO (in this case GRO is responsible for about 50% of the CPU utilization). perf top while replaying 64 parallel IP/TCP streams merging in GRO: (gro_receive_network_flush is compiled inline to tcp_gro_receive) net-next: 6.94% [kernel] [k] inet_gro_receive 3.02% [kernel] [k] tcp_gro_receive patch applied: 4.27% [kernel] [k] tcp_gro_receive 4.22% [kernel] [k] inet_gro_receive perf top while replaying 64 parallel IP/IP/TCP streams merging in GRO (same results for any encapsulation, in this case inet_gro_receive is top offender in net-next) net-next: 10.09% [kernel] [k] inet_gro_receive 2.08% [kernel] [k] tcp_gro_receive patch applied: 6.97% [kernel] [k] inet_gro_receive 3.68% [kernel] [k] tcp_gro_receive Signed-off-by: Richard Gobert <richardbgobert@gmail.com> Reviewed-by: Willem de Bruijn <willemb@google.com> Link: https://lore.kernel.org/r/20240509190819.2985-3-richardbgobert@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-05-13net: gro: use cb instead of skb->network_headerRichard Gobert
This patch converts references of skb->network_header to napi_gro_cb's network_offset and inner_network_offset. Signed-off-by: Richard Gobert <richardbgobert@gmail.com> Reviewed-by: Willem de Bruijn <willemb@google.com> Link: https://lore.kernel.org/r/20240509190819.2985-2-richardbgobert@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-05-13inet: fix inet_fill_ifaddr() flags truncationEric Dumazet
I missed that (struct ifaddrmsg)->ifa_flags was only 8bits, while (struct in_ifaddr)->ifa_flags is 32bits. Use a temporary 32bit variable as I did in set_ifa_lifetime() and check_lifetime(). Fixes: 3ddc2231c810 ("inet: annotate data-races around ifa->ifa_flags") Reported-by: Yu Watanabe <watanabe.yu@gmail.com> Dianosed-by: Yu Watanabe <watanabe.yu@gmail.com> Closes: https://github.com/systemd/systemd/pull/32666#issuecomment-2103977928 Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Larysa Zaremba <larysa.zaremba@intel.com> Reviewed-by: David Ahern <dsahern@kernel.org> Link: https://lore.kernel.org/r/20240510072932.2678952-1-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-05-13Merge tag 'nf-next-24-05-12' of ↵Jakub Kicinski
git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf-next Pablo Neira Ayuso says: ==================== Netfilter updates for net-next The following patchset contains Netfilter updates for net-next: Patch #1 skips transaction if object type provides no .update interface. Patch #2 skips NETDEV_CHANGENAME which is unused. Patch #3 enables conntrack to handle Multicast Router Advertisements and Multicast Router Solicitations from the Multicast Router Discovery protocol (RFC4286) as untracked opposed to invalid packets. From Linus Luessing. Patch #4 updates DCCP conntracker to mark invalid as invalid, instead of dropping them, from Jason Xing. Patch #5 uses NF_DROP instead of -NF_DROP since NF_DROP is 0, also from Jason. Patch #6 removes reference in netfilter's sysctl documentation on pickup entries which were already removed by Florian Westphal. Patch #7 removes check for IPS_OFFLOAD flag to disable early drop which allows to evict entries from the conntrack table, also from Florian. Patches #8 to #16 updates nf_tables pipapo set backend to allocate the datastructure copy on-demand from preparation phase, to better deal with OOM situations where .commit step is too late to fail. Series from Florian Westphal. Patch #17 adds a selftest with packetdrill to cover conntrack TCP state transitions, also from Florian. Patch #18 use GFP_KERNEL to clone elements from control plane to avoid quick atomic reserves exhaustion with large sets, reporter refers to million entries magnitude. * tag 'nf-next-24-05-12' of git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf-next: netfilter: nf_tables: allow clone callbacks to sleep selftests: netfilter: add packetdrill based conntrack tests netfilter: nft_set_pipapo: remove dirty flag netfilter: nft_set_pipapo: move cloning of match info to insert/removal path netfilter: nft_set_pipapo: prepare pipapo_get helper for on-demand clone netfilter: nft_set_pipapo: merge deactivate helper into caller netfilter: nft_set_pipapo: prepare walk function for on-demand clone netfilter: nft_set_pipapo: prepare destroy function for on-demand clone netfilter: nft_set_pipapo: make pipapo_clone helper return NULL netfilter: nft_set_pipapo: move prove_locking helper around netfilter: conntrack: remove flowtable early-drop test netfilter: conntrack: documentation: remove reference to non-existent sysctl netfilter: use NF_DROP instead of -NF_DROP netfilter: conntrack: dccp: try not to drop skb in conntrack netfilter: conntrack: fix ct-state for ICMPv6 Multicast Router Discovery netfilter: nf_tables: remove NETDEV_CHANGENAME from netdev chain event handler netfilter: nf_tables: skip transaction if update object is not implemented ==================== Link: https://lore.kernel.org/r/20240512161436.168973-1-pablo@netfilter.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-05-09tcp: get rid of twsk_unique()Eric Dumazet
DCCP is going away soon, and had no twsk_unique() method. We can directly call tcp_twsk_unique() for TCP sockets. Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com> Link: https://lore.kernel.org/r/20240507164140.940547-1-edumazet@google.com 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>
2024-05-08net/ipv4: add tracepoint for icmp_sendPeilin He
Introduce a tracepoint for icmp_send, which can help users to get more detail information conveniently when icmp abnormal events happen. 1. Giving an usecase example: ============================= When an application experiences packet loss due to an unreachable UDP destination port, the kernel will send an exception message through the icmp_send function. By adding a trace point for icmp_send, developers or system administrators can obtain detailed information about the UDP packet loss, including the type, code, source address, destination address, source port, and destination port. This facilitates the trouble-shooting of UDP packet loss issues especially for those network-service applications. 2. Operation Instructions: ========================== Switch to the tracing directory. cd /sys/kernel/tracing Filter for destination port unreachable. echo "type==3 && code==3" > events/icmp/icmp_send/filter Enable trace event. echo 1 > events/icmp/icmp_send/enable 3. Result View: ================ udp_client_erro-11370 [002] ...s.12 124.728002: icmp_send: icmp_send: type=3, code=3. From 127.0.0.1:41895 to 127.0.0.1:6666 ulen=23 skbaddr=00000000589b167a Signed-off-by: Peilin He <he.peilin@zte.com.cn> Signed-off-by: xu xin <xu.xin16@zte.com.cn> Reviewed-by: Yunkai Zhang <zhang.yunkai@zte.com.cn> Cc: Yang Yang <yang.yang29@zte.com.cn> Cc: Liu Chun <liu.chun2@zte.com.cn> Cc: Xuexin Jiang <jiang.xuexin@zte.com.cn> Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2024-05-07net: annotate writes on dev->mtu from ndo_change_mtu()Eric Dumazet
Simon reported that ndo_change_mtu() methods were never updated to use WRITE_ONCE(dev->mtu, new_mtu) as hinted in commit 501a90c94510 ("inet: protect against too small mtu values.") We read dev->mtu without holding RTNL in many places, with READ_ONCE() annotations. It is time to take care of ndo_change_mtu() methods to use corresponding WRITE_ONCE() Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Simon Horman <horms@kernel.org> Closes: https://lore.kernel.org/netdev/20240505144608.GB67882@kernel.org/ Reviewed-by: Jacob Keller <jacob.e.keller@intel.com> Reviewed-by: Sabrina Dubroca <sd@queasysnail.net> Reviewed-by: Simon Horman <horms@kernel.org> Acked-by: Shannon Nelson <shannon.nelson@amd.com> Link: https://lore.kernel.org/r/20240506102812.3025432-1-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-05-07rtnetlink: allow rtnl_fill_link_netnsid() to run under RCU protectionEric Dumazet
We want to be able to run rtnl_fill_ifinfo() under RCU protection instead of RTNL in the future. All rtnl_link_ops->get_link_net() methods already using dev_net() are ready. I added READ_ONCE() annotations on others. Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Simon Horman <horms@kernel.org> Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2024-05-06Merge tag 'ipsec-next-2024-05-03' of ↵Jakub Kicinski
git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec-next Steffen Klassert says: ==================== pull request (net-next): ipsec-next 2024-05-03 1) Remove Obsolete UDP_ENCAP_ESPINUDP_NON_IKE Support. This was defined by an early version of an IETF draft that did not make it to a standard. 2) Introduce direction attribute for xfrm states. xfrm states have a direction, a stsate can be used either for input or output packet processing. Add a direction to xfrm states to make it clear for what a xfrm state is used. * tag 'ipsec-next-2024-05-03' of git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec-next: xfrm: Restrict SA direction attribute to specific netlink message types xfrm: Add dir validation to "in" data path lookup xfrm: Add dir validation to "out" data path lookup xfrm: Add Direction to the SA in or out udpencap: Remove Obsolete UDP_ENCAP_ESPINUDP_NON_IKE Support ==================== Link: https://lore.kernel.org/r/20240503082732.2835810-1-steffen.klassert@secunet.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-05-06netfilter: use NF_DROP instead of -NF_DROPJason Xing
At the beginning in 2009 one patch [1] introduced collecting drop counter in nf_conntrack_in() by returning -NF_DROP. Later, another patch [2] changed the return value of tcp_packet() which now is renamed to nf_conntrack_tcp_packet() from -NF_DROP to NF_DROP. As we can see, that -NF_DROP should be corrected. Similarly, there are other two points where the -NF_DROP is used. Well, as NF_DROP is equal to 0, inverting NF_DROP makes no sense as patch [2] said many years ago. [1] commit 7d1e04598e5e ("netfilter: nf_conntrack: account packets drop by tcp_packet()") [2] commit ec8d540969da ("netfilter: conntrack: fix dropping packet after l4proto->packet()") Signed-off-by: Jason Xing <kernelxing@tencent.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2024-05-06net: add heuristic for enabling TCP fraglist GROFelix Fietkau
When forwarding TCP after GRO, software segmentation is very expensive, especially when the checksum needs to be recalculated. One case where that's currently unavoidable is when routing packets over PPPoE. Performance improves significantly when using fraglist GRO implemented in the same way as for UDP. When NETIF_F_GRO_FRAGLIST is enabled, perform a lookup for an established socket in the same netns as the receiving device. While this may not cover all relevant use cases in multi-netns configurations, it should be good enough for most configurations that need this. Here's a measurement of running 2 TCP streams through a MediaTek MT7622 device (2-core Cortex-A53), which runs NAT with flow offload enabled from one ethernet port to PPPoE on another ethernet port + cake qdisc set to 1Gbps. rx-gro-list off: 630 Mbit/s, CPU 35% idle rx-gro-list on: 770 Mbit/s, CPU 40% idle Acked-by: Paolo Abeni <pabeni@redhat.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Felix Fietkau <nbd@nbd.name> Reviewed-by: David Ahern <dsahern@kernel.org> Reviewed-by: Willem de Bruijn <willemb@google.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com>
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