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7 daysipv4: Fix incorrect TOS in fibmatch route get replyIdo Schimmel1-1/+1
The TOS value that is returned to user space in the route get reply is the one with which the lookup was performed ('fl4->flowi4_tos'). This is fine when the matched route is configured with a TOS as it would not match if its TOS value did not match the one with which the lookup was performed. However, matching on TOS is only performed when the route's TOS is not zero. It is therefore possible to have the kernel incorrectly return a non-zero TOS: # ip link add name dummy1 up type dummy # ip address add 192.0.2.1/24 dev dummy1 # ip route get fibmatch 192.0.2.2 tos 0xfc 192.0.2.0/24 tos 0x1c dev dummy1 proto kernel scope link src 192.0.2.1 Fix by instead returning the DSCP field from the FIB result structure which was populated during the route lookup. Output after the patch: # ip link add name dummy1 up type dummy # ip address add 192.0.2.1/24 dev dummy1 # ip route get fibmatch 192.0.2.2 tos 0xfc 192.0.2.0/24 dev dummy1 proto kernel scope link src 192.0.2.1 Extend the existing selftests to not only verify that the correct route is returned, but that it is also returned with correct "tos" value (or without it). Fixes: b61798130f1b ("net: ipv4: RTM_GETROUTE: return matched fib result when requested") Signed-off-by: Ido Schimmel <idosch@nvidia.com> Reviewed-by: David Ahern <dsahern@kernel.org> Reviewed-by: Guillaume Nault <gnault@redhat.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com>
7 daysipv4: Fix incorrect TOS in route get replyIdo Schimmel2-7/+8
The TOS value that is returned to user space in the route get reply is the one with which the lookup was performed ('fl4->flowi4_tos'). This is fine when the matched route is configured with a TOS as it would not match if its TOS value did not match the one with which the lookup was performed. However, matching on TOS is only performed when the route's TOS is not zero. It is therefore possible to have the kernel incorrectly return a non-zero TOS: # ip link add name dummy1 up type dummy # ip address add 192.0.2.1/24 dev dummy1 # ip route get 192.0.2.2 tos 0xfc 192.0.2.2 tos 0x1c dev dummy1 src 192.0.2.1 uid 0 cache Fix by adding a DSCP field to the FIB result structure (inside an existing 4 bytes hole), populating it in the route lookup and using it when filling the route get reply. Output after the patch: # ip link add name dummy1 up type dummy # ip address add 192.0.2.1/24 dev dummy1 # ip route get 192.0.2.2 tos 0xfc 192.0.2.2 dev dummy1 src 192.0.2.1 uid 0 cache Fixes: 1a00fee4ffb2 ("ipv4: Remove rt_key_{src,dst,tos} from struct rtable.") Signed-off-by: Ido Schimmel <idosch@nvidia.com> Reviewed-by: David Ahern <dsahern@kernel.org> Reviewed-by: Guillaume Nault <gnault@redhat.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com>
9 daystcp: Replace strncpy() with strscpy()Kees Cook1-4/+5
Replace the deprecated[1] uses of strncpy() in tcp_ca_get_name_by_key() and tcp_get_default_congestion_control(). The callers use the results as standard C strings (via nla_put_string() and proc handlers respectively), so trailing padding is not needed. Since passing the destination buffer arguments decays it to a pointer, the size can't be trivially determined by the compiler. ca->name is the same length in both cases, so strscpy() won't fail (when ca->name is NUL-terminated). Include the length explicitly instead of using the 2-argument strscpy(). Link: https://github.com/KSPP/linux/issues/90 [1] Signed-off-by: Kees Cook <kees@kernel.org> Reviewed-by: Simon Horman <horms@kernel.org> Reviewed-by: Eric Dumazet <edumazet@google.com> Link: https://patch.msgid.link/20240714041111.it.918-kees@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
9 daystcp: Don't access uninit tcp_rsk(req)->ao_keyid in tcp_create_openreq_child().Kuniyuki Iwashima1-7/+8
syzkaller reported KMSAN splat in tcp_create_openreq_child(). [0] The uninit variable is tcp_rsk(req)->ao_keyid. tcp_rsk(req)->ao_keyid is initialised only when tcp_conn_request() finds a valid TCP AO option in SYN. Then, tcp_rsk(req)->used_tcp_ao is set accordingly. Let's not read tcp_rsk(req)->ao_keyid when tcp_rsk(req)->used_tcp_ao is false. [0]: BUG: KMSAN: uninit-value in tcp_create_openreq_child+0x198b/0x1ff0 net/ipv4/tcp_minisocks.c:610 tcp_create_openreq_child+0x198b/0x1ff0 net/ipv4/tcp_minisocks.c:610 tcp_v4_syn_recv_sock+0x18e/0x2170 net/ipv4/tcp_ipv4.c:1754 tcp_check_req+0x1a3e/0x20c0 net/ipv4/tcp_minisocks.c:852 tcp_v4_rcv+0x26a4/0x53a0 net/ipv4/tcp_ipv4.c:2265 ip_protocol_deliver_rcu+0x884/0x1270 net/ipv4/ip_input.c:205 ip_local_deliver_finish+0x30f/0x530 net/ipv4/ip_input.c:233 NF_HOOK include/linux/netfilter.h:314 [inline] ip_local_deliver+0x230/0x4c0 net/ipv4/ip_input.c:254 dst_input include/net/dst.h:460 [inline] ip_sublist_rcv_finish net/ipv4/ip_input.c:580 [inline] ip_list_rcv_finish net/ipv4/ip_input.c:631 [inline] ip_sublist_rcv+0x10f7/0x13e0 net/ipv4/ip_input.c:639 ip_list_rcv+0x952/0x9c0 net/ipv4/ip_input.c:674 __netif_receive_skb_list_ptype net/core/dev.c:5703 [inline] __netif_receive_skb_list_core+0xd92/0x11d0 net/core/dev.c:5751 __netif_receive_skb_list net/core/dev.c:5803 [inline] netif_receive_skb_list_internal+0xd8f/0x1350 net/core/dev.c:5895 gro_normal_list include/net/gro.h:515 [inline] napi_complete_done+0x3f2/0x990 net/core/dev.c:6246 e1000_clean+0x1fa4/0x5e50 drivers/net/ethernet/intel/e1000/e1000_main.c:3808 __napi_poll+0xd9/0x990 net/core/dev.c:6771 napi_poll net/core/dev.c:6840 [inline] net_rx_action+0x90f/0x17e0 net/core/dev.c:6962 handle_softirqs+0x152/0x6b0 kernel/softirq.c:554 __do_softirq kernel/softirq.c:588 [inline] invoke_softirq kernel/softirq.c:428 [inline] __irq_exit_rcu kernel/softirq.c:637 [inline] irq_exit_rcu+0x5d/0x120 kernel/softirq.c:649 common_interrupt+0x83/0x90 arch/x86/kernel/irq.c:278 asm_common_interrupt+0x26/0x40 arch/x86/include/asm/idtentry.h:693 __msan_instrument_asm_store+0xd6/0xe0 arch_atomic_inc arch/x86/include/asm/atomic.h:53 [inline] raw_atomic_inc include/linux/atomic/atomic-arch-fallback.h:992 [inline] atomic_inc include/linux/atomic/atomic-instrumented.h:436 [inline] page_ref_inc include/linux/page_ref.h:153 [inline] folio_ref_inc include/linux/page_ref.h:160 [inline] filemap_map_order0_folio mm/filemap.c:3596 [inline] filemap_map_pages+0x11c7/0x2270 mm/filemap.c:3644 do_fault_around mm/memory.c:4879 [inline] do_read_fault mm/memory.c:4912 [inline] do_fault mm/memory.c:5051 [inline] do_pte_missing mm/memory.c:3897 [inline] handle_pte_fault mm/memory.c:5381 [inline] __handle_mm_fault mm/memory.c:5524 [inline] handle_mm_fault+0x3677/0x6f00 mm/memory.c:5689 do_user_addr_fault+0x1373/0x2b20 arch/x86/mm/fault.c:1338 handle_page_fault arch/x86/mm/fault.c:1481 [inline] exc_page_fault+0x54/0xc0 arch/x86/mm/fault.c:1539 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623 Uninit was stored to memory at: tcp_create_openreq_child+0x1984/0x1ff0 net/ipv4/tcp_minisocks.c:611 tcp_v4_syn_recv_sock+0x18e/0x2170 net/ipv4/tcp_ipv4.c:1754 tcp_check_req+0x1a3e/0x20c0 net/ipv4/tcp_minisocks.c:852 tcp_v4_rcv+0x26a4/0x53a0 net/ipv4/tcp_ipv4.c:2265 ip_protocol_deliver_rcu+0x884/0x1270 net/ipv4/ip_input.c:205 ip_local_deliver_finish+0x30f/0x530 net/ipv4/ip_input.c:233 NF_HOOK include/linux/netfilter.h:314 [inline] ip_local_deliver+0x230/0x4c0 net/ipv4/ip_input.c:254 dst_input include/net/dst.h:460 [inline] ip_sublist_rcv_finish net/ipv4/ip_input.c:580 [inline] ip_list_rcv_finish net/ipv4/ip_input.c:631 [inline] ip_sublist_rcv+0x10f7/0x13e0 net/ipv4/ip_input.c:639 ip_list_rcv+0x952/0x9c0 net/ipv4/ip_input.c:674 __netif_receive_skb_list_ptype net/core/dev.c:5703 [inline] __netif_receive_skb_list_core+0xd92/0x11d0 net/core/dev.c:5751 __netif_receive_skb_list net/core/dev.c:5803 [inline] netif_receive_skb_list_internal+0xd8f/0x1350 net/core/dev.c:5895 gro_normal_list include/net/gro.h:515 [inline] napi_complete_done+0x3f2/0x990 net/core/dev.c:6246 e1000_clean+0x1fa4/0x5e50 drivers/net/ethernet/intel/e1000/e1000_main.c:3808 __napi_poll+0xd9/0x990 net/core/dev.c:6771 napi_poll net/core/dev.c:6840 [inline] net_rx_action+0x90f/0x17e0 net/core/dev.c:6962 handle_softirqs+0x152/0x6b0 kernel/softirq.c:554 __do_softirq kernel/softirq.c:588 [inline] invoke_softirq kernel/softirq.c:428 [inline] __irq_exit_rcu kernel/softirq.c:637 [inline] irq_exit_rcu+0x5d/0x120 kernel/softirq.c:649 common_interrupt+0x83/0x90 arch/x86/kernel/irq.c:278 asm_common_interrupt+0x26/0x40 arch/x86/include/asm/idtentry.h:693 Uninit was created at: __alloc_pages_noprof+0x82d/0xcb0 mm/page_alloc.c:4706 __alloc_pages_node_noprof include/linux/gfp.h:269 [inline] alloc_pages_node_noprof include/linux/gfp.h:296 [inline] alloc_slab_page mm/slub.c:2265 [inline] allocate_slab mm/slub.c:2428 [inline] new_slab+0x2af/0x14e0 mm/slub.c:2481 ___slab_alloc+0xf73/0x3150 mm/slub.c:3667 __slab_alloc mm/slub.c:3757 [inline] __slab_alloc_node mm/slub.c:3810 [inline] slab_alloc_node mm/slub.c:3990 [inline] kmem_cache_alloc_noprof+0x53a/0x9f0 mm/slub.c:4009 reqsk_alloc_noprof net/ipv4/inet_connection_sock.c:920 [inline] inet_reqsk_alloc+0x63/0x700 net/ipv4/inet_connection_sock.c:951 tcp_conn_request+0x339/0x4860 net/ipv4/tcp_input.c:7177 tcp_v4_conn_request+0x13b/0x190 net/ipv4/tcp_ipv4.c:1719 tcp_rcv_state_process+0x2dd/0x4a10 net/ipv4/tcp_input.c:6711 tcp_v4_do_rcv+0xbee/0x10d0 net/ipv4/tcp_ipv4.c:1932 tcp_v4_rcv+0x3fad/0x53a0 net/ipv4/tcp_ipv4.c:2334 ip_protocol_deliver_rcu+0x884/0x1270 net/ipv4/ip_input.c:205 ip_local_deliver_finish+0x30f/0x530 net/ipv4/ip_input.c:233 NF_HOOK include/linux/netfilter.h:314 [inline] ip_local_deliver+0x230/0x4c0 net/ipv4/ip_input.c:254 dst_input include/net/dst.h:460 [inline] ip_sublist_rcv_finish net/ipv4/ip_input.c:580 [inline] ip_list_rcv_finish net/ipv4/ip_input.c:631 [inline] ip_sublist_rcv+0x10f7/0x13e0 net/ipv4/ip_input.c:639 ip_list_rcv+0x952/0x9c0 net/ipv4/ip_input.c:674 __netif_receive_skb_list_ptype net/core/dev.c:5703 [inline] __netif_receive_skb_list_core+0xd92/0x11d0 net/core/dev.c:5751 __netif_receive_skb_list net/core/dev.c:5803 [inline] netif_receive_skb_list_internal+0xd8f/0x1350 net/core/dev.c:5895 gro_normal_list include/net/gro.h:515 [inline] napi_complete_done+0x3f2/0x990 net/core/dev.c:6246 e1000_clean+0x1fa4/0x5e50 drivers/net/ethernet/intel/e1000/e1000_main.c:3808 __napi_poll+0xd9/0x990 net/core/dev.c:6771 napi_poll net/core/dev.c:6840 [inline] net_rx_action+0x90f/0x17e0 net/core/dev.c:6962 handle_softirqs+0x152/0x6b0 kernel/softirq.c:554 __do_softirq kernel/softirq.c:588 [inline] invoke_softirq kernel/softirq.c:428 [inline] __irq_exit_rcu kernel/softirq.c:637 [inline] irq_exit_rcu+0x5d/0x120 kernel/softirq.c:649 common_interrupt+0x83/0x90 arch/x86/kernel/irq.c:278 asm_common_interrupt+0x26/0x40 arch/x86/include/asm/idtentry.h:693 CPU: 0 PID: 239 Comm: modprobe Tainted: G B 6.10.0-rc7-01816-g852e42cc2dd4 #3 1107521f0c7b55c9309062382d0bda9f604dbb6d Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014 Fixes: 06b22ef29591 ("net/tcp: Wire TCP-AO to request sockets") Reported-by: syzkaller <syzkaller@googlegroups.com> 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/20240714161719.6528-1-kuniyu@amazon.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>
9 daysMerge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski3-4/+19
Merge in late fixes to prepare for the 6.11 net-next PR. Conflicts: 93c3a96c301f ("net: pse-pd: Do not return EOPNOSUPP if config is null") 4cddb0f15ea9 ("net: ethtool: pse-pd: Fix possible null-deref") 30d7b6727724 ("net: ethtool: Add new power limit get and set features") https://lore.kernel.org/20240715123204.623520bb@canb.auug.org.au/ Signed-off-by: Jakub Kicinski <kuba@kernel.org>
10 daysMerge tag 'ipsec-next-2024-07-13' of ↵Jakub Kicinski2-2/+23
git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec-next Steffen Klassert says: ==================== pull request (net-next): ipsec-next 2024-07-13 1) Support sending NAT keepalives in ESP in UDP states. Userspace IKE daemon had to do this before, but the kernel can better keep track of it. From Eyal Birger. 2) Support IPsec crypto offload for IPv6 ESP and IPv4 UDP-encapsulated ESP data paths. Currently, IPsec crypto offload is enabled for GRO code path only. This patchset support UDP encapsulation for the non GRO path. From Mike Yu. * tag 'ipsec-next-2024-07-13' of git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec-next: xfrm: Support crypto offload for outbound IPv4 UDP-encapsulated ESP packet xfrm: Support crypto offload for inbound IPv4 UDP-encapsulated ESP packet xfrm: Allow UDP encapsulation in crypto offload control path xfrm: Support crypto offload for inbound IPv6 ESP packets not in GRO path xfrm: support sending NAT keepalives in ESP in UDP states ==================== Link: https://patch.msgid.link/20240713102416.3272997-1-steffen.klassert@secunet.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
11 daysipv4: fix source address selection with route leakNicolas Dichtel1-2/+11
By default, an address assigned to the output interface is selected when the source address is not specified. This is problematic when a route, configured in a vrf, uses an interface from another vrf (aka route leak). The original vrf does not own the selected source address. Let's add a check against the output interface and call the appropriate function to select the source address. CC: stable@vger.kernel.org Fixes: 8cbb512c923d ("net: Add source address lookup op for VRF") Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com> Reviewed-by: David Ahern <dsahern@kernel.org> Link: https://patch.msgid.link/20240710081521.3809742-2-nicolas.dichtel@6wind.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
11 daysMerge tag 'ipsec-2024-07-11' of ↵Jakub Kicinski2-2/+8
git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec Steffen Klassert says: ==================== pull request (net): ipsec 2024-07-11 1) Fix esp_output_tail_tcp() on unsupported ESPINTCP. From Hagar Hemdan. 2) Fix two bugs in the recently introduced SA direction separation. From Antony Antony. 3) Fix unregister netdevice hang on hardware offload. We had to add another list where skbs linked to that are unlinked from the lists (deleted) but not yet freed. 4) Fix netdev reference count imbalance in xfrm_state_find. From Jianbo Liu. 5) Call xfrm_dev_policy_delete when killingi them on offloaded policies. Jianbo Liu. * tag 'ipsec-2024-07-11' of git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec: xfrm: call xfrm_dev_policy_delete when kill policy xfrm: fix netdev reference count imbalance xfrm: Export symbol xfrm_dev_state_delete. xfrm: Fix unregister netdevice hang on hardware offload. xfrm: Log input direction mismatch error in one place xfrm: Fix input error path memory access net: esp: cleanup esp_output_tail_tcp() in case of unsupported ESPINTCP ==================== Link: https://patch.msgid.link/20240711100025.1949454-1-steffen.klassert@secunet.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
11 daystcp: Don't drop SYN+ACK for simultaneous connect().Kuniyuki Iwashima1-0/+9
RFC 9293 states that in the case of simultaneous connect(), the connection gets established when SYN+ACK is received. [0] TCP Peer A TCP Peer B 1. CLOSED CLOSED 2. SYN-SENT --> <SEQ=100><CTL=SYN> ... 3. SYN-RECEIVED <-- <SEQ=300><CTL=SYN> <-- SYN-SENT 4. ... <SEQ=100><CTL=SYN> --> SYN-RECEIVED 5. SYN-RECEIVED --> <SEQ=100><ACK=301><CTL=SYN,ACK> ... 6. ESTABLISHED <-- <SEQ=300><ACK=101><CTL=SYN,ACK> <-- SYN-RECEIVED 7. ... <SEQ=100><ACK=301><CTL=SYN,ACK> --> ESTABLISHED However, since commit 0c24604b68fc ("tcp: implement RFC 5961 4.2"), such a SYN+ACK is dropped in tcp_validate_incoming() and responded with Challenge ACK. For example, the write() syscall in the following packetdrill script fails with -EAGAIN, and wrong SNMP stats get incremented. 0 socket(..., SOCK_STREAM|SOCK_NONBLOCK, IPPROTO_TCP) = 3 +0 connect(3, ..., ...) = -1 EINPROGRESS (Operation now in progress) +0 > S 0:0(0) <mss 1460,sackOK,TS val 1000 ecr 0,nop,wscale 8> +0 < S 0:0(0) win 1000 <mss 1000> +0 > S. 0:0(0) ack 1 <mss 1460,sackOK,TS val 3308134035 ecr 0,nop,wscale 8> +0 < S. 0:0(0) ack 1 win 1000 +0 write(3, ..., 100) = 100 +0 > P. 1:101(100) ack 1 -- # packetdrill cross-synack.pkt cross-synack.pkt:13: runtime error in write call: Expected result 100 but got -1 with errno 11 (Resource temporarily unavailable) # nstat ... TcpExtTCPChallengeACK 1 0.0 TcpExtTCPSYNChallenge 1 0.0 The problem is that bpf_skops_established() is triggered by the Challenge ACK instead of SYN+ACK. This causes the bpf prog to miss the chance to check if the peer supports a TCP option that is expected to be exchanged in SYN and SYN+ACK. Let's accept a bare SYN+ACK for active-open TCP_SYN_RECV sockets to avoid such a situation. Note that tcp_ack_snd_check() in tcp_rcv_state_process() is skipped not to send an unnecessary ACK, but this could be a bit risky for net.git, so this targets for net-next. Link: https://www.rfc-editor.org/rfc/rfc9293.html#section-3.5-7 [0] Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Link: https://patch.msgid.link/20240710171246.87533-2-kuniyu@amazon.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
13 daysxfrm: Support crypto offload for outbound IPv4 UDP-encapsulated ESP packetMike Yu2-2/+23
esp_xmit() is already able to handle UDP encapsulation through the call to esp_output_head(). However, the ESP header and the outer IP header are not correct and need to be corrected. Test: Enabled both dir=in/out IPsec crypto offload, and verified IPv4 UDP-encapsulated ESP packets on both wifi/cellular network Signed-off-by: Mike Yu <yumike@google.com> Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
13 daysMerge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski3-6/+26
Cross-merge networking fixes after downstream PR. Conflicts: net/sched/act_ct.c 26488172b029 ("net/sched: Fix UAF when resolving a clash") 3abbd7ed8b76 ("act_ct: prepare for stolen verdict coming from conntrack and nat engine") No adjacent changes. Signed-off-by: Jakub Kicinski <kuba@kernel.org>
14 daysudp: Set SOCK_RCU_FREE earlier in udp_lib_get_port().Kuniyuki Iwashima1-1/+3
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>
2024-07-11tcp: avoid too many retransmit packetsEric Dumazet1-2/+13
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>
2024-07-06tcp: fix incorrect undo caused by DSACK of TLP retransmitNeal Cardwell2-3/+10
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>
2024-07-05Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski3-1/+11
Cross-merge networking fixes after downstream PR. Conflicts: drivers/net/phy/aquantia/aquantia.h 219343755eae ("net: phy: aquantia: add missing include guards") 61578f679378 ("net: phy: aquantia: add support for PHY LEDs") drivers/net/ethernet/wangxun/libwx/wx_hw.c bd07a9817846 ("net: txgbe: remove separate irq request for MSI and INTx") b501d261a5b3 ("net: txgbe: add FDIR ATR support") https://lore.kernel.org/all/20240703112936.483c1975@canb.auug.org.au/ include/linux/mlx5/mlx5_ifc.h 048a403648fc ("net/mlx5: IFC updates for changing max EQs") 99be56171fa9 ("net/mlx5e: SHAMPO, Re-enable HW-GRO") https://lore.kernel.org/all/20240701133951.6926b2e3@canb.auug.org.au/ Adjacent changes: drivers/net/wireless/intel/iwlwifi/mvm/mac80211.c 4130c67cd123 ("wifi: iwlwifi: mvm: check vif for NULL/ERR_PTR before dereference") 3f3126515fbe ("wifi: iwlwifi: mvm: add mvm-specific guard") include/net/mac80211.h 816c6bec09ed ("wifi: mac80211: fix BSS_CHANGED_UNSOL_BCAST_PROBE_RESP") 5a009b42e041 ("wifi: mac80211: track changes in AP's TPE") Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-07-04inet_diag: Initialize pad field in struct inet_diag_req_v2Shigeru Yoshida1-0/+2
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 Iwashima1-0/+7
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 Kicinski1-0/+1
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>
2024-06-29udp: Allow GSO transmit from devices with no checksum offloadJakub Sitnicki2-2/+9
Today sending a UDP GSO packet from a TUN device results in an EIO error: import fcntl, os, struct from socket import * TUNSETIFF = 0x400454CA IFF_TUN = 0x0001 IFF_NO_PI = 0x1000 UDP_SEGMENT = 103 tun_fd = os.open("/dev/net/tun", os.O_RDWR) ifr = struct.pack("16sH", b"tun0", IFF_TUN | IFF_NO_PI) fcntl.ioctl(tun_fd, TUNSETIFF, ifr) os.system("ip addr add 192.0.2.1/24 dev tun0") os.system("ip link set dev tun0 up") s = socket(AF_INET, SOCK_DGRAM) s.setsockopt(SOL_UDP, UDP_SEGMENT, 1200) s.sendto(b"x" * 3000, ("192.0.2.2", 9)) # EIO This is due to a check in the udp stack if the egress device offers checksum offload. While TUN/TAP devices, by default, don't advertise this capability because it requires support from the TUN/TAP reader. However, the GSO stack has a software fallback for checksum calculation, which we can use. This way we don't force UDP_SEGMENT users to handle the EIO error and implement a segmentation fallback. Lift the restriction so that UDP_SEGMENT can be used with any egress device. We also need to adjust the UDP GSO code to match the GSO stack expectation about ip_summed field, as set in commit 8d63bee643f1 ("net: avoid skb_warn_bad_offload false positives on UFO"). Otherwise we will hit the bad offload check. Users should, however, expect a potential performance impact when batch-sending packets with UDP_SEGMENT without checksum offload on the egress device. In such case the packet payload is read twice: first during the sendmsg syscall when copying data from user memory, and then in the GSO stack for checksum computation. This double memory read can be less efficient than a regular sendmsg where the checksum is calculated during the initial data copy from user memory. Signed-off-by: Jakub Sitnicki <jakub@cloudflare.com> Reviewed-by: Willem de Bruijn <willemb@google.com> Link: https://patch.msgid.link/20240626-linux-udpgso-v2-1-422dfcbd6b48@cloudflare.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-06-28UPSTREAM: tcp: fix DSACK undo in fast recovery to call tcp_try_to_open()Neal Cardwell1-1/+1
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>
2024-06-27Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski2-16/+46
Cross-merge networking fixes after downstream PR. No conflicts. Adjacent changes: e3f02f32a050 ("ionic: fix kernel panic due to multi-buffer handling") d9c04209990b ("ionic: Mark error paths in the data path as unlikely") Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-06-26tcp: fix tcp_rcv_fastopen_synack() to enter TCP_CA_Loss for failed TFONeal Cardwell1-11/+27
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 SYNluoxuanqiang2-5/+19
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>
2024-06-25net/ipv4: Use nested-BH locking for ipv4_tcp_sk.Sebastian Andrzej Siewior1-4/+11
ipv4_tcp_sk is a per-CPU variable and relies on disabled BH for its locking. Without per-CPU locking in local_bh_disable() on PREEMPT_RT this data structure requires explicit locking. Make a struct with a sock member (original ipv4_tcp_sk) and a local_lock_t and use local_lock_nested_bh() for locking. This change adds only lockdep coverage and does not alter the functional behaviour for !PREEMPT_RT. Cc: David Ahern <dsahern@kernel.org> Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Link: https://patch.msgid.link/20240620132727.660738-7-bigeasy@linutronix.de Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-06-25net/tcp_sigpool: Use nested-BH locking for sigpool_scratch.Sebastian Andrzej Siewior1-4/+13
sigpool_scratch is a per-CPU variable and relies on disabled BH for its locking. Without per-CPU locking in local_bh_disable() on PREEMPT_RT this data structure requires explicit locking. Make a struct with a pad member (original sigpool_scratch) and a local_lock_t and use local_lock_nested_bh() for locking. This change adds only lockdep coverage and does not alter the functional behaviour for !PREEMPT_RT. Cc: David Ahern <dsahern@kernel.org> Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Link: https://patch.msgid.link/20240620132727.660738-6-bigeasy@linutronix.de Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-06-20Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski3-23/+59
Cross-merge networking fixes after downstream PR. Conflicts: drivers/net/ethernet/broadcom/bnxt/bnxt.c 1e7962114c10 ("bnxt_en: Restore PTP tx_avail count in case of skb_pad() error") 165f87691a89 ("bnxt_en: add timestamping statistics support") No adjacent changes. Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-06-20net/tcp_ao: Don't leak ao_info on error-pathDmitry Safonov1-2/+4
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>
2024-06-19udp: use sk_skb_reason_drop to free rx packetsYan Zhai1-5/+5
Replace kfree_skb_reason with sk_skb_reason_drop and pass the receiving socket to the tracepoint. Reported-by: kernel test robot <lkp@intel.com> Closes: https://lore.kernel.org/r/202406011751.NpVN0sSk-lkp@intel.com/ Signed-off-by: Yan Zhai <yan@cloudflare.com> Acked-by: Jesper Dangaard Brouer <hawk@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2024-06-19tcp: use sk_skb_reason_drop to free rx packetsYan Zhai3-5/+5
Replace kfree_skb_reason with sk_skb_reason_drop and pass the receiving socket to the tracepoint. Reported-by: kernel test robot <lkp@intel.com> Closes: https://lore.kernel.org/r/202406011539.jhwBd7DX-lkp@intel.com/ Signed-off-by: Yan Zhai <yan@cloudflare.com> Acked-by: Jesper Dangaard Brouer <hawk@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2024-06-19net: raw: use sk_skb_reason_drop to free rx packetsYan Zhai1-2/+2
Replace kfree_skb_reason with sk_skb_reason_drop and pass the receiving socket to the tracepoint. Signed-off-by: Yan Zhai <yan@cloudflare.com> Acked-by: Jesper Dangaard Brouer <hawk@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2024-06-19ping: use sk_skb_reason_drop to free rx packetsYan Zhai1-1/+1
Replace kfree_skb_reason with sk_skb_reason_drop and pass the receiving socket to the tracepoint. Signed-off-by: Yan Zhai <yan@cloudflare.com> Acked-by: Jesper Dangaard Brouer <hawk@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2024-06-18tcp: clear tp->retrans_stamp in tcp_rcv_fastopen_synack()Eric Dumazet1-0/+1
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>
2024-06-18fou: remove warn in gue_gro_receive on unsupported protocolWillem de Bruijn1-1/+1
Drop the WARN_ON_ONCE inn gue_gro_receive if the encapsulated type is not known or does not have a GRO handler. Such a packet is easily constructed. Syzbot generates them and sets off this warning. Remove the warning as it is expected and not actionable. The warning was previously reduced from WARN_ON to WARN_ON_ONCE in commit 270136613bf7 ("fou: Do WARN_ON_ONCE in gue_gro_receive for bad proto callbacks"). Signed-off-by: Willem de Bruijn <willemb@google.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Link: https://lore.kernel.org/r/20240614122552.1649044-1-willemdebruijn.kernel@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-06-17xfrm: Log input direction mismatch error in one placeAntony Antony1-0/+7
Previously, the offload data path decrypted the packet before checking the direction, leading to error logging and packet dropping. However, dropped packets wouldn't be visible in tcpdump or audit log. With this fix, the offload path, upon noticing SA direction mismatch, will pass the packet to the stack without decrypting it. The L3 layer will then log the error, audit, and drop ESP without decrypting or decapsulating it. This also ensures that the slow path records the error and audit log, making dropped packets visible in tcpdump. Fixes: 304b44f0d5a4 ("xfrm: Add dir validation to "in" data path lookup") Signed-off-by: Antony Antony <antony.antony@secunet.com> Reviewed-by: Simon Horman <horms@kernel.org> Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
2024-06-14cipso: make cipso_v4_skbuff_delattr() fully remove the CIPSO optionsOndrej Mosnacek1-25/+54
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 Mosnacek1-4/+8
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>
2024-06-13Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski1-1/+5
Cross-merge networking fixes after downstream PR. No conflicts, no adjacent changes. Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-06-13net: ipv4: Add a sysctl to set multipath hash seedPetr Machata1-0/+66
When calculating hashes for the purpose of multipath forwarding, both IPv4 and IPv6 code currently fall back on flow_hash_from_keys(). That uses a randomly-generated seed. That's a fine choice by default, but unfortunately some deployments may need a tighter control over the seed used. In this patch, make the seed configurable by adding a new sysctl key, net.ipv4.fib_multipath_hash_seed to control the seed. This seed is used specifically for multipath forwarding and not for the other concerns that flow_hash_from_keys() is used for, such as queue selection. Expose the knob as sysctl because other such settings, such as headers to hash, are also handled that way. Like those, the multipath hash seed is a per-netns variable. Despite being placed in the net.ipv4 namespace, the multipath seed sysctl is used for both IPv4 and IPv6, similarly to e.g. a number of TCP variables. The seed used by flow_hash_from_keys() is a 128-bit quantity. However it seems that usually the seed is a much more modest value. 32 bits seem typical (Cisco, Cumulus), some systems go even lower. For that reason, and to decouple the user interface from implementation details, go with a 32-bit quantity, which is then quadruplicated to form the siphash key. Signed-off-by: Petr Machata <petrm@nvidia.com> Reviewed-by: Ido Schimmel <idosch@nvidia.com> Reviewed-by: Nikolay Aleksandrov <razor@blackwall.org> Reviewed-by: David Ahern <dsahern@kernel.org> Link: https://lore.kernel.org/r/20240607151357.421181-3-petrm@nvidia.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-06-13net: ipv4,ipv6: Pass multipath hash computation through a helperPetr Machata1-6/+6
The following patches will add a sysctl to control multipath hash seed. In order to centralize the hash computation, add a helper, fib_multipath_hash_from_keys(), and have all IPv4 and IPv6 route.c invocations of flow_hash_from_keys() go through this helper instead. Signed-off-by: Petr Machata <petrm@nvidia.com> Reviewed-by: Ido Schimmel <idosch@nvidia.com> Reviewed-by: Nikolay Aleksandrov <razor@blackwall.org> Reviewed-by: David Ahern <dsahern@kernel.org> Link: https://lore.kernel.org/r/20240607151357.421181-2-petrm@nvidia.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-06-12net/tcp: Remove tcp_hash_fail()Dmitry Safonov2-34/+0
Now there are tracepoints, that cover all functionality of tcp_hash_fail(), but also wire up missing places They are also faster, can be disabled and provide filtering. This potentially may create a regression if a userspace depends on dmesg logs. Fingers crossed, let's see if anyone complains in reality. Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Dmitry Safonov <0x7f454c46@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2024-06-12net/tcp: Add tcp-md5 and tcp-ao tracepointsDmitry Safonov4-2/+38
Instead of forcing userspace to parse dmesg (that's what currently is happening, at least in codebase of my current company), provide a better way, that can be enabled/disabled in runtime. Currently, there are already tcp events, add hashing related ones there, too. Rasdaemon currently exercises net_dev_xmit_timeout, devlink_health_report, but it'll be trivial to teach it to deal with failed hashes. Otherwise, BGP may trace/log them itself. Especially exciting for possible investigations is key rotation (RNext_key requests). Suggested-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Dmitry Safonov <0x7f454c46@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2024-06-12net/tcp: Move tcp_inbound_hash() from headersDmitry Safonov1-2/+72
Two reasons: 1. It's grown up enough 2. In order to not do header spaghetti by including <trace/events/tcp.h>, which is necessary for TCP tracepoints. While at it, unexport and make static tcp_inbound_ao_hash(). Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Dmitry Safonov <0x7f454c46@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2024-06-12net/tcp: Add a helper tcp_ao_hdr_maclen()Dmitry Safonov1-1/+1
It's going to be used more in TCP-AO tracepoints. Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Dmitry Safonov <0x7f454c46@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2024-06-12net/tcp: Use static_branch_tcp_{md5,ao} to drop ifdefsDmitry Safonov1-6/+2
It's possible to clean-up some ifdefs by hiding that tcp_{md5,ao}_needed static branch is defined and compiled only under related configs, since commit 4c8530dc7d7d ("net/tcp: Only produce AO/MD5 logs if there are any keys"). Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Dmitry Safonov <0x7f454c46@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2024-06-12ip_tunnel: Move stats allocation to coreBreno Leitao1-8/+2
With commit 34d21de99cea9 ("net: Move {l,t,d}stats allocation to core and convert veth & vrf"), stats allocation could be done on net core instead of this driver. With this new approach, the driver doesn't have to bother with error handling (allocation failure checking, making sure free happens in the right spot, etc). This is core responsibility now. Move ip_tunnel driver to leverage the core allocation. All the ip_tunnel_init() users call ip_tunnel_init() as part of their .ndo_init callback. The .ndo_init callback is called before the stats allocation in netdev_register(), thus, the allocation will happen before the netdev is visible. Signed-off-by: Breno Leitao <leitao@debian.org> Reviewed-by: Simon Horman <horms@kernel.org> Link: https://lore.kernel.org/r/20240607084420.3932875-1-leitao@debian.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-06-11tcp: use signed arithmetic in tcp_rtx_probe0_timed_out()Eric Dumazet1-1/+5
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>
2024-06-11Merge tag 'for-netdev' of ↵Jakub Kicinski1-3/+3
https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next Daniel Borkmann says: ==================== pull-request: bpf-next 2024-06-06 We've added 54 non-merge commits during the last 10 day(s) which contain a total of 50 files changed, 1887 insertions(+), 527 deletions(-). The main changes are: 1) Add a user space notification mechanism via epoll when a struct_ops object is getting detached/unregistered, from Kui-Feng Lee. 2) Big batch of BPF selftest refactoring for sockmap and BPF congctl tests, from Geliang Tang. 3) Add BTF field (type and string fields, right now) iterator support to libbpf instead of using existing callback-based approaches, from Andrii Nakryiko. 4) Extend BPF selftests for the latter with a new btf_field_iter selftest, from Alan Maguire. 5) Add new kfuncs for a generic, open-coded bits iterator, from Yafang Shao. 6) Fix BPF selftests' kallsyms_find() helper under kernels configured with CONFIG_LTO_CLANG_THIN, from Yonghong Song. 7) Remove a bunch of unused structs in BPF selftests, from David Alan Gilbert. 8) Convert test_sockmap section names into names understood by libbpf so it can deduce program type and attach type, from Jakub Sitnicki. 9) Extend libbpf with the ability to configure log verbosity via LIBBPF_LOG_LEVEL environment variable, from Mykyta Yatsenko. 10) Fix BPF selftests with regards to bpf_cookie and find_vma flakiness in nested VMs, from Song Liu. 11) Extend riscv32/64 JITs to introduce shift/add helpers to generate Zba optimization, from Xiao Wang. 12) Enable BPF programs to declare arrays and struct fields with kptr, bpf_rb_root, and bpf_list_head, from Kui-Feng Lee. * tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (54 commits) selftests/bpf: Drop useless arguments of do_test in bpf_tcp_ca selftests/bpf: Use start_test in test_dctcp in bpf_tcp_ca selftests/bpf: Use start_test in test_dctcp_fallback in bpf_tcp_ca selftests/bpf: Add start_test helper in bpf_tcp_ca selftests/bpf: Use connect_to_fd_opts in do_test in bpf_tcp_ca libbpf: Auto-attach struct_ops BPF maps in BPF skeleton selftests/bpf: Add btf_field_iter selftests selftests/bpf: Fix send_signal test with nested CONFIG_PARAVIRT libbpf: Remove callback-based type/string BTF field visitor helpers bpftool: Use BTF field iterator in btfgen libbpf: Make use of BTF field iterator in BTF handling code libbpf: Make use of BTF field iterator in BPF linker code libbpf: Add BTF field iterator selftests/bpf: Ignore .llvm.<hash> suffix in kallsyms_find() selftests/bpf: Fix bpf_cookie and find_vma in nested VM selftests/bpf: Test global bpf_list_head arrays. selftests/bpf: Test global bpf_rb_root arrays and fields in nested struct types. selftests/bpf: Test kptr arrays and kptrs in nested struct fields. bpf: limit the number of levels of a nested struct type. bpf: look into the types of the fields of a struct type recursively. ... ==================== Link: https://lore.kernel.org/r/20240606223146.23020-1-daniel@iogearbox.net Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-06-10tcp: move inet_twsk_schedule helper out of headerFlorian Westphal1-0/+5
Its no longer used outside inet_timewait_sock.c, so move it there. Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: David S. Miller <davem@davemloft.net>
2024-06-10net: tcp: un-pin the tw_timerFlorian Westphal2-8/+4
After previous patch, even if timer fires immediately on another CPU, context that schedules the timer now holds the ehash spinlock, so timer cannot reap tw socket until ehash lock is released. BH disable is moved into hashdance_schedule. Signed-off-by: Florian Westphal <fw@strlen.de> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2024-06-10net: tcp/dccp: prepare for tw_timer un-pinningValentin Schneider3-10/+47
The TCP timewait timer is proving to be problematic for setups where scheduler CPU isolation is achieved at runtime via cpusets (as opposed to statically via isolcpus=domains). What happens there is a CPU goes through tcp_time_wait(), arming the time_wait timer, then gets isolated. TCP_TIMEWAIT_LEN later, the timer fires, causing interference for the now-isolated CPU. This is conceptually similar to the issue described in commit e02b93124855 ("workqueue: Unbind kworkers before sending them to exit()") Move inet_twsk_schedule() to within inet_twsk_hashdance(), with the ehash lock held. Expand the lock's critical section from inet_twsk_kill() to inet_twsk_deschedule_put(), serializing the scheduling vs descheduling of the timer. IOW, this prevents the following race: tcp_time_wait() inet_twsk_hashdance() inet_twsk_deschedule_put() del_timer_sync() inet_twsk_schedule() Thanks to Paolo Abeni for suggesting to leverage the ehash lock. This also restores a comment from commit ec94c2696f0b ("tcp/dccp: avoid one atomic operation for timewait hashdance") as inet_twsk_hashdance() had a "Step 1" and "Step 3" comment, but the "Step 2" had gone missing. inet_twsk_deschedule_put() now acquires the ehash spinlock to synchronize with inet_twsk_hashdance_schedule(). To ease possible regression search, actual un-pin is done in next patch. Link: https://lore.kernel.org/all/ZPhpfMjSiHVjQkTk@localhost.localdomain/ Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Valentin Schneider <vschneid@redhat.com> Co-developed-by: Florian Westphal <fw@strlen.de> Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: David S. Miller <davem@davemloft.net>