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2020-02-11tcp: clear tp->segs_{in|out} in tcp_disconnect()Eric Dumazet1-0/+2
[ Upstream commit 784f8344de750a41344f4bbbebb8507a730fc99c ] tp->segs_in and tp->segs_out need to be cleared in tcp_disconnect(). tcp_disconnect() is rarely used, but it is worth fixing it. Fixes: 2efd055c53c0 ("tcp: add tcpi_segs_in and tcpi_segs_out to tcp_info") Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Marcelo Ricardo Leitner <mleitner@redhat.com> Cc: Yuchung Cheng <ycheng@google.com> Cc: Neal Cardwell <ncardwell@google.com> Acked-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-11tcp: clear tp->data_segs{in|out} in tcp_disconnect()Eric Dumazet1-0/+2
[ Upstream commit db7ffee6f3eb3683cdcaeddecc0a630a14546fe3 ] tp->data_segs_in and tp->data_segs_out need to be cleared in tcp_disconnect(). tcp_disconnect() is rarely used, but it is worth fixing it. Fixes: a44d6eacdaf5 ("tcp: Add RFC4898 tcpEStatsPerfDataSegsOut/In") Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Martin KaFai Lau <kafai@fb.com> Cc: Yuchung Cheng <ycheng@google.com> Cc: Neal Cardwell <ncardwell@google.com> Acked-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-11tcp: clear tp->delivered in tcp_disconnect()Eric Dumazet1-0/+1
[ Upstream commit 2fbdd56251b5c62f96589f39eded277260de7267 ] tp->delivered needs to be cleared in tcp_disconnect(). tcp_disconnect() is rarely used, but it is worth fixing it. Fixes: ddf1af6fa00e ("tcp: new delivery accounting") Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Yuchung Cheng <ycheng@google.com> Cc: Neal Cardwell <ncardwell@google.com> Acked-by: Yuchung Cheng <ycheng@google.com> Acked-by: Neal Cardwell <ncardwell@google.com> Acked-by: Soheil Hassas Yeganeh <soheil@google.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-11tcp: clear tp->total_retrans in tcp_disconnect()Eric Dumazet1-0/+1
[ Upstream commit c13c48c00a6bc1febc73902505bdec0967bd7095 ] total_retrans needs to be cleared in tcp_disconnect(). tcp_disconnect() is rarely used, but it is worth fixing it. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: SeongJae Park <sjpark@amazon.de> Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-06vti[6]: fix packet tx through bpf_redirect()Nicolas Dichtel1-2/+11
[ Upstream commit 95224166a9032ff5d08fca633d37113078ce7d01 ] With an ebpf program that redirects packets through a vti[6] interface, the packets are dropped because no dst is attached. This could also be reproduced with an AF_PACKET socket, with the following python script (vti1 is an ip_vti interface): import socket send_s = socket.socket(socket.AF_PACKET, socket.SOCK_RAW, 0) # scapy # p = IP(src='10.100.0.2', dst='10.200.0.1')/ICMP(type='echo-request') # raw(p) req = b'E\x00\x00\x1c\x00\x01\x00\x00@\x01e\xb2\nd\x00\x02\n\xc8\x00\x01\x08\x00\xf7\xff\x00\x00\x00\x00' send_s.sendto(req, ('vti1', 0x800, 0, 0)) Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com> Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-02-01net: include struct nhmsg size in nh nlmsg sizeStephen Worley1-1/+3
[ Upstream commit f9e95555757915fc194288862d2978e370fe316b ] Include the size of struct nhmsg size when calculating how much of a payload to allocate in a new netlink nexthop notification message. Without this, we will fail to fill the skbuff at certain nexthop group sizes. You can reproduce the failure with the following iproute2 commands: ip link add dummy1 type dummy ip link add dummy2 type dummy ip link add dummy3 type dummy ip link add dummy4 type dummy ip link add dummy5 type dummy ip link add dummy6 type dummy ip link add dummy7 type dummy ip link add dummy8 type dummy ip link add dummy9 type dummy ip link add dummy10 type dummy ip link add dummy11 type dummy ip link add dummy12 type dummy ip link add dummy13 type dummy ip link add dummy14 type dummy ip link add dummy15 type dummy ip link add dummy16 type dummy ip link add dummy17 type dummy ip link add dummy18 type dummy ip link add dummy19 type dummy ip ro add 1.1.1.1/32 dev dummy1 ip ro add 1.1.1.2/32 dev dummy2 ip ro add 1.1.1.3/32 dev dummy3 ip ro add 1.1.1.4/32 dev dummy4 ip ro add 1.1.1.5/32 dev dummy5 ip ro add 1.1.1.6/32 dev dummy6 ip ro add 1.1.1.7/32 dev dummy7 ip ro add 1.1.1.8/32 dev dummy8 ip ro add 1.1.1.9/32 dev dummy9 ip ro add 1.1.1.10/32 dev dummy10 ip ro add 1.1.1.11/32 dev dummy11 ip ro add 1.1.1.12/32 dev dummy12 ip ro add 1.1.1.13/32 dev dummy13 ip ro add 1.1.1.14/32 dev dummy14 ip ro add 1.1.1.15/32 dev dummy15 ip ro add 1.1.1.16/32 dev dummy16 ip ro add 1.1.1.17/32 dev dummy17 ip ro add 1.1.1.18/32 dev dummy18 ip ro add 1.1.1.19/32 dev dummy19 ip next add id 1 via 1.1.1.1 dev dummy1 ip next add id 2 via 1.1.1.2 dev dummy2 ip next add id 3 via 1.1.1.3 dev dummy3 ip next add id 4 via 1.1.1.4 dev dummy4 ip next add id 5 via 1.1.1.5 dev dummy5 ip next add id 6 via 1.1.1.6 dev dummy6 ip next add id 7 via 1.1.1.7 dev dummy7 ip next add id 8 via 1.1.1.8 dev dummy8 ip next add id 9 via 1.1.1.9 dev dummy9 ip next add id 10 via 1.1.1.10 dev dummy10 ip next add id 11 via 1.1.1.11 dev dummy11 ip next add id 12 via 1.1.1.12 dev dummy12 ip next add id 13 via 1.1.1.13 dev dummy13 ip next add id 14 via 1.1.1.14 dev dummy14 ip next add id 15 via 1.1.1.15 dev dummy15 ip next add id 16 via 1.1.1.16 dev dummy16 ip next add id 17 via 1.1.1.17 dev dummy17 ip next add id 18 via 1.1.1.18 dev dummy18 ip next add id 19 via 1.1.1.19 dev dummy19 ip next add id 1111 group 1/2/3/4/5/6/7/8/9/10/11/12/13/14/15/16/17/18/19 ip next del id 1111 Fixes: 430a049190de ("nexthop: Add support for nexthop groups") Signed-off-by: Stephen Worley <sworley@cumulusnetworks.com> Reviewed-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-01-29xfrm: support output_mark for offload ESP packetsUlrich Weber1-0/+2
commit 4e4362d2bf2a49ff44dbbc9585207977ca3d71d0 upstream. Commit 9b42c1f179a6 ("xfrm: Extend the output_mark") added output_mark support but missed ESP offload support. xfrm_smark_get() is not called within xfrm_input() for packets coming from esp4_gro_receive() or esp6_gro_receive(). Therefore call xfrm_smark_get() directly within these functions. Fixes: 9b42c1f179a6 ("xfrm: Extend the output_mark to support input direction and masking.") Signed-off-by: Ulrich Weber <ulrich.weber@gmail.com> Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-01-29ipv4: Detect rollover in specific fib table dumpDavid Ahern1-0/+6
[ Upstream commit 9827c0634e461703abf81e8cc8b7adf5da5886d0 ] Sven-Haegar reported looping on fib dumps when 255.255.255.255 route has been added to a table. The looping is caused by the key rolling over from FFFFFFFF to 0. When dumping a specific table only, we need a means to detect when the table dump is done. The key and count saved to cb args are both 0 only at the start of the table dump. If key is 0 and count > 0, then we are in the rollover case. Detect and return to avoid looping. This only affects dumps of a specific table; for dumps of all tables (the case prior to the change in the Fixes tag) inet_dump_fib moved the entry counter to the next table and reset the cb args used by fib_table_dump and fn_trie_dump_leaf, so the rollover ffffffff back to 0 did not cause looping with the dumps. Fixes: effe67926624 ("net: Enable kernel side filtering of route dumps") Reported-by: Sven-Haegar Koch <haegar@sdinet.de> Signed-off-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-01-29fou: Fix IPv6 netlink policyKristian Evensen1-2/+2
[ Upstream commit bb48eb9b12a95db9d679025927269d4adda6dbd1 ] When submitting v2 of "fou: Support binding FoU socket" (1713cb37bf67), I accidentally sent the wrong version of the patch and one fix was missing. In the initial version of the patch, as well as the version 2 that I submitted, I incorrectly used ".type" for the two V6-attributes. The correct is to use ".len". Reported-by: Dmitry Vyukov <dvyukov@google.com> Fixes: 1713cb37bf67 ("fou: Support binding FoU socket") Signed-off-by: Kristian Evensen <kristian.evensen@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-01-29tcp: do not leave dangling pointers in tp->highest_sackEric Dumazet3-0/+3
[ Upstream commit 2bec445f9bf35e52e395b971df48d3e1e5dc704a ] Latest commit 853697504de0 ("tcp: Fix highest_sack and highest_sack_seq") apparently allowed syzbot to trigger various crashes in TCP stack [1] I believe this commit only made things easier for syzbot to find its way into triggering use-after-frees. But really the bugs could lead to bad TCP behavior or even plain crashes even for non malicious peers. I have audited all calls to tcp_rtx_queue_unlink() and tcp_rtx_queue_unlink_and_free() and made sure tp->highest_sack would be updated if we are removing from rtx queue the skb that tp->highest_sack points to. These updates were missing in three locations : 1) tcp_clean_rtx_queue() [This one seems quite serious, I have no idea why this was not caught earlier] 2) tcp_rtx_queue_purge() [Probably not a big deal for normal operations] 3) tcp_send_synack() [Probably not a big deal for normal operations] [1] BUG: KASAN: use-after-free in tcp_highest_sack_seq include/net/tcp.h:1864 [inline] BUG: KASAN: use-after-free in tcp_highest_sack_seq include/net/tcp.h:1856 [inline] BUG: KASAN: use-after-free in tcp_check_sack_reordering+0x33c/0x3a0 net/ipv4/tcp_input.c:891 Read of size 4 at addr ffff8880a488d068 by task ksoftirqd/1/16 CPU: 1 PID: 16 Comm: ksoftirqd/1 Not tainted 5.5.0-rc5-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x197/0x210 lib/dump_stack.c:118 print_address_description.constprop.0.cold+0xd4/0x30b mm/kasan/report.c:374 __kasan_report.cold+0x1b/0x41 mm/kasan/report.c:506 kasan_report+0x12/0x20 mm/kasan/common.c:639 __asan_report_load4_noabort+0x14/0x20 mm/kasan/generic_report.c:134 tcp_highest_sack_seq include/net/tcp.h:1864 [inline] tcp_highest_sack_seq include/net/tcp.h:1856 [inline] tcp_check_sack_reordering+0x33c/0x3a0 net/ipv4/tcp_input.c:891 tcp_try_undo_partial net/ipv4/tcp_input.c:2730 [inline] tcp_fastretrans_alert+0xf74/0x23f0 net/ipv4/tcp_input.c:2847 tcp_ack+0x2577/0x5bf0 net/ipv4/tcp_input.c:3710 tcp_rcv_established+0x6dd/0x1e90 net/ipv4/tcp_input.c:5706 tcp_v4_do_rcv+0x619/0x8d0 net/ipv4/tcp_ipv4.c:1619 tcp_v4_rcv+0x307f/0x3b40 net/ipv4/tcp_ipv4.c:2001 ip_protocol_deliver_rcu+0x5a/0x880 net/ipv4/ip_input.c:204 ip_local_deliver_finish+0x23b/0x380 net/ipv4/ip_input.c:231 NF_HOOK include/linux/netfilter.h:307 [inline] NF_HOOK include/linux/netfilter.h:301 [inline] ip_local_deliver+0x1e9/0x520 net/ipv4/ip_input.c:252 dst_input include/net/dst.h:442 [inline] ip_rcv_finish+0x1db/0x2f0 net/ipv4/ip_input.c:428 NF_HOOK include/linux/netfilter.h:307 [inline] NF_HOOK include/linux/netfilter.h:301 [inline] ip_rcv+0xe8/0x3f0 net/ipv4/ip_input.c:538 __netif_receive_skb_one_core+0x113/0x1a0 net/core/dev.c:5148 __netif_receive_skb+0x2c/0x1d0 net/core/dev.c:5262 process_backlog+0x206/0x750 net/core/dev.c:6093 napi_poll net/core/dev.c:6530 [inline] net_rx_action+0x508/0x1120 net/core/dev.c:6598 __do_softirq+0x262/0x98c kernel/softirq.c:292 run_ksoftirqd kernel/softirq.c:603 [inline] run_ksoftirqd+0x8e/0x110 kernel/softirq.c:595 smpboot_thread_fn+0x6a3/0xa40 kernel/smpboot.c:165 kthread+0x361/0x430 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352 Allocated by task 10091: save_stack+0x23/0x90 mm/kasan/common.c:72 set_track mm/kasan/common.c:80 [inline] __kasan_kmalloc mm/kasan/common.c:513 [inline] __kasan_kmalloc.constprop.0+0xcf/0xe0 mm/kasan/common.c:486 kasan_slab_alloc+0xf/0x20 mm/kasan/common.c:521 slab_post_alloc_hook mm/slab.h:584 [inline] slab_alloc_node mm/slab.c:3263 [inline] kmem_cache_alloc_node+0x138/0x740 mm/slab.c:3575 __alloc_skb+0xd5/0x5e0 net/core/skbuff.c:198 alloc_skb_fclone include/linux/skbuff.h:1099 [inline] sk_stream_alloc_skb net/ipv4/tcp.c:875 [inline] sk_stream_alloc_skb+0x113/0xc90 net/ipv4/tcp.c:852 tcp_sendmsg_locked+0xcf9/0x3470 net/ipv4/tcp.c:1282 tcp_sendmsg+0x30/0x50 net/ipv4/tcp.c:1432 inet_sendmsg+0x9e/0xe0 net/ipv4/af_inet.c:807 sock_sendmsg_nosec net/socket.c:652 [inline] sock_sendmsg+0xd7/0x130 net/socket.c:672 __sys_sendto+0x262/0x380 net/socket.c:1998 __do_sys_sendto net/socket.c:2010 [inline] __se_sys_sendto net/socket.c:2006 [inline] __x64_sys_sendto+0xe1/0x1a0 net/socket.c:2006 do_syscall_64+0xfa/0x790 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x49/0xbe Freed by task 10095: save_stack+0x23/0x90 mm/kasan/common.c:72 set_track mm/kasan/common.c:80 [inline] kasan_set_free_info mm/kasan/common.c:335 [inline] __kasan_slab_free+0x102/0x150 mm/kasan/common.c:474 kasan_slab_free+0xe/0x10 mm/kasan/common.c:483 __cache_free mm/slab.c:3426 [inline] kmem_cache_free+0x86/0x320 mm/slab.c:3694 kfree_skbmem+0x178/0x1c0 net/core/skbuff.c:645 __kfree_skb+0x1e/0x30 net/core/skbuff.c:681 sk_eat_skb include/net/sock.h:2453 [inline] tcp_recvmsg+0x1252/0x2930 net/ipv4/tcp.c:2166 inet_recvmsg+0x136/0x610 net/ipv4/af_inet.c:838 sock_recvmsg_nosec net/socket.c:886 [inline] sock_recvmsg net/socket.c:904 [inline] sock_recvmsg+0xce/0x110 net/socket.c:900 __sys_recvfrom+0x1ff/0x350 net/socket.c:2055 __do_sys_recvfrom net/socket.c:2073 [inline] __se_sys_recvfrom net/socket.c:2069 [inline] __x64_sys_recvfrom+0xe1/0x1a0 net/socket.c:2069 do_syscall_64+0xfa/0x790 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x49/0xbe The buggy address belongs to the object at ffff8880a488d040 which belongs to the cache skbuff_fclone_cache of size 456 The buggy address is located 40 bytes inside of 456-byte region [ffff8880a488d040, ffff8880a488d208) The buggy address belongs to the page: page:ffffea0002922340 refcount:1 mapcount:0 mapping:ffff88821b057000 index:0x0 raw: 00fffe0000000200 ffffea00022a5788 ffffea0002624a48 ffff88821b057000 raw: 0000000000000000 ffff8880a488d040 0000000100000006 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8880a488cf00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8880a488cf80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff8880a488d000: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb ^ ffff8880a488d080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880a488d100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb Fixes: 853697504de0 ("tcp: Fix highest_sack and highest_sack_seq") Fixes: 50895b9de1d3 ("tcp: highest_sack fix") Fixes: 737ff314563c ("tcp: use sequence distance to detect reordering") Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Cambda Zhu <cambda@linux.alibaba.com> Cc: Yuchung Cheng <ycheng@google.com> Cc: Neal Cardwell <ncardwell@google.com> Acked-by: Neal Cardwell <ncardwell@google.com> Acked-by: Yuchung Cheng <ycheng@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-01-29tcp_bbr: improve arithmetic division in bbr_update_bw()Wen Yang1-2/+1
[ Upstream commit 5b2f1f3070b6447b76174ea8bfb7390dc6253ebd ] do_div() does a 64-by-32 division. Use div64_long() instead of it if the divisor is long, to avoid truncation to 32-bit. And as a nice side effect also cleans up the function a bit. Signed-off-by: Wen Yang <wenyang@linux.alibaba.com> Cc: Eric Dumazet <edumazet@google.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: Alexey Kuznetsov <kuznet@ms2.inr.ac.ru> Cc: Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org> Cc: netdev@vger.kernel.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-01-29Revert "udp: do rmem bulk free even if the rx sk queue is empty"Paolo Abeni1-1/+2
[ Upstream commit d39ca2590d10712f412add7a88e1dd467a7246f4 ] This reverts commit 0d4a6608f68c7532dcbfec2ea1150c9761767d03. Willem reported that after commit 0d4a6608f68c ("udp: do rmem bulk free even if the rx sk queue is empty") the memory allocated by an almost idle system with many UDP sockets can grow a lot. For stable kernel keep the solution as simple as possible and revert the offending commit. Reported-by: Willem de Bruijn <willemdebruijn.kernel@gmail.com> Diagnosed-by: Eric Dumazet <eric.dumazet@gmail.com> Fixes: 0d4a6608f68c ("udp: do rmem bulk free even if the rx sk queue is empty") Signed-off-by: Paolo Abeni <pabeni@redhat.com> Acked-by: Willem de Bruijn <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-01-29net, ip_tunnel: fix namespaces moveWilliam Dauchy1-3/+1
[ Upstream commit d0f418516022c32ecceaf4275423e5bd3f8743a9 ] in the same manner as commit 690afc165bb3 ("net: ip6_gre: fix moving ip6gre between namespaces"), fix namespace moving as it was broken since commit 2e15ea390e6f ("ip_gre: Add support to collect tunnel metadata."). Indeed, the ip6_gre commit removed the local flag for collect_md condition, so there is no reason to keep it for ip_gre/ip_tunnel. this patch will fix both ip_tunnel and ip_gre modules. Fixes: 2e15ea390e6f ("ip_gre: Add support to collect tunnel metadata.") Signed-off-by: William Dauchy <w.dauchy@criteo.com> Acked-by: Nicolas Dichtel <nicolas.dichtel@6wind.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-01-23tcp: refine rule to allow EPOLLOUT generation under mem pressureEric Dumazet1-4/+2
commit 216808c6ba6d00169fd2aa928ec3c0e63bef254f upstream. At the time commit ce5ec440994b ("tcp: ensure epoll edge trigger wakeup when write queue is empty") was added to the kernel, we still had a single write queue, combining rtx and write queues. Once we moved the rtx queue into a separate rb-tree, testing if sk_write_queue is empty has been suboptimal. Indeed, if we have packets in the rtx queue, we probably want to delay the EPOLLOUT generation at the time incoming packets will free them, making room, but more importantly avoiding flooding application with EPOLLOUT events. Solution is to use tcp_rtx_and_write_queues_empty() helper. Fixes: 75c119afe14f ("tcp: implement rb-tree based retransmit queue") Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Jason Baron <jbaron@akamai.com> Cc: Neal Cardwell <ncardwell@google.com> Acked-by: Soheil Hassas Yeganeh <soheil@google.com> Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-01-23tcp: fix marked lost packets not being retransmittedPengcheng Yang1-3/+4
[ Upstream commit e176b1ba476cf36f723cfcc7a9e57f3cb47dec70 ] When the packet pointed to by retransmit_skb_hint is unlinked by ACK, retransmit_skb_hint will be set to NULL in tcp_clean_rtx_queue(). If packet loss is detected at this time, retransmit_skb_hint will be set to point to the current packet loss in tcp_verify_retransmit_hint(), then the packets that were previously marked lost but not retransmitted due to the restriction of cwnd will be skipped and cannot be retransmitted. To fix this, when retransmit_skb_hint is NULL, retransmit_skb_hint can be reset only after all marked lost packets are retransmitted (retrans_out >= lost_out), otherwise we need to traverse from tcp_rtx_queue_head in tcp_xmit_retransmit_queue(). Packetdrill to demonstrate: // Disable RACK and set max_reordering to keep things simple 0 `sysctl -q net.ipv4.tcp_recovery=0` +0 `sysctl -q net.ipv4.tcp_max_reordering=3` // Establish a connection +0 socket(..., SOCK_STREAM, IPPROTO_TCP) = 3 +0 setsockopt(3, SOL_SOCKET, SO_REUSEADDR, [1], 4) = 0 +0 bind(3, ..., ...) = 0 +0 listen(3, 1) = 0 +.1 < S 0:0(0) win 32792 <mss 1000,sackOK,nop,nop,nop,wscale 7> +0 > S. 0:0(0) ack 1 <...> +.01 < . 1:1(0) ack 1 win 257 +0 accept(3, ..., ...) = 4 // Send 8 data segments +0 write(4, ..., 8000) = 8000 +0 > P. 1:8001(8000) ack 1 // Enter recovery and 1:3001 is marked lost +.01 < . 1:1(0) ack 1 win 257 <sack 3001:4001,nop,nop> +0 < . 1:1(0) ack 1 win 257 <sack 5001:6001 3001:4001,nop,nop> +0 < . 1:1(0) ack 1 win 257 <sack 5001:7001 3001:4001,nop,nop> // Retransmit 1:1001, now retransmit_skb_hint points to 1001:2001 +0 > . 1:1001(1000) ack 1 // 1001:2001 was ACKed causing retransmit_skb_hint to be set to NULL +.01 < . 1:1(0) ack 2001 win 257 <sack 5001:8001 3001:4001,nop,nop> // Now retransmit_skb_hint points to 4001:5001 which is now marked lost // BUG: 2001:3001 was not retransmitted +0 > . 2001:3001(1000) ack 1 Signed-off-by: Pengcheng Yang <yangpc@wangsu.com> Acked-by: Neal Cardwell <ncardwell@google.com> Tested-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-01-23netfilter: arp_tables: init netns pointer in xt_tgdtor_param structFlorian Westphal1-9/+10
commit 212e7f56605ef9688d0846db60c6c6ec06544095 upstream. An earlier commit (1b789577f655060d98d20e, "netfilter: arp_tables: init netns pointer in xt_tgchk_param struct") fixed missing net initialization for arptables, but turns out it was incomplete. We can get a very similar struct net NULL deref during error unwinding: general protection fault: 0000 [#1] PREEMPT SMP KASAN RIP: 0010:xt_rateest_put+0xa1/0x440 net/netfilter/xt_RATEEST.c:77 xt_rateest_tg_destroy+0x72/0xa0 net/netfilter/xt_RATEEST.c:175 cleanup_entry net/ipv4/netfilter/arp_tables.c:509 [inline] translate_table+0x11f4/0x1d80 net/ipv4/netfilter/arp_tables.c:587 do_replace net/ipv4/netfilter/arp_tables.c:981 [inline] do_arpt_set_ctl+0x317/0x650 net/ipv4/netfilter/arp_tables.c:1461 Also init the netns pointer in xt_tgdtor_param struct. Fixes: add67461240c1d ("netfilter: add struct net * to target parameters") Reported-by: syzbot+91bdd8eece0f6629ec8b@syzkaller.appspotmail.com Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-01-23bpf/sockmap: Read psock ingress_msg before sk_receive_queueLingpeng Chen1-6/+6
commit e7a5f1f1cd0008e5ad379270a8657e121eedb669 upstream. Right now in tcp_bpf_recvmsg, sock read data first from sk_receive_queue if not empty than psock->ingress_msg otherwise. If a FIN packet arrives and there's also some data in psock->ingress_msg, the data in psock->ingress_msg will be purged. It is always happen when request to a HTTP1.0 server like python SimpleHTTPServer since the server send FIN packet after data is sent out. Fixes: 604326b41a6fb ("bpf, sockmap: convert to generic sk_msg interface") Reported-by: Arika Chen <eaglesora@gmail.com> Suggested-by: Arika Chen <eaglesora@gmail.com> Signed-off-by: Lingpeng Chen <forrest0579@gmail.com> Signed-off-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Song Liu <songliubraving@fb.com> Link: https://lore.kernel.org/bpf/20200109014833.18951-1-forrest0579@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-01-23bpf: Sockmap/tls, fix pop data with SK_DROP return codeJohn Fastabend1-4/+1
commit 7361d44896ff20d48bdd502d1a0cd66308055d45 upstream. When user returns SK_DROP we need to reset the number of copied bytes to indicate to the user the bytes were dropped and not sent. If we don't reset the copied arg sendmsg will return as if those bytes were copied giving the user a positive return value. This works as expected today except in the case where the user also pops bytes. In the pop case the sg.size is reduced but we don't correctly account for this when copied bytes is reset. The popped bytes are not accounted for and we return a small positive value potentially confusing the user. The reason this happens is due to a typo where we do the wrong comparison when accounting for pop bytes. In this fix notice the if/else is not needed and that we have a similar problem if we push data except its not visible to the user because if delta is larger the sg.size we return a negative value so it appears as an error regardless. Fixes: 7246d8ed4dcce ("bpf: helper to pop data from messages") Signed-off-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Jonathan Lemon <jonathan.lemon@gmail.com> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/bpf/20200111061206.8028-9-john.fastabend@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-01-23bpf: Sockmap/tls, push write_space updates through ulp updatesJohn Fastabend1-2/+4
commit 33bfe20dd7117dd81fd896a53f743a233e1ad64f upstream. When sockmap sock with TLS enabled is removed we cleanup bpf/psock state and call tcp_update_ulp() to push updates to TLS ULP on top. However, we don't push the write_space callback up and instead simply overwrite the op with the psock stored previous op. This may or may not be correct so to ensure we don't overwrite the TLS write space hook pass this field to the ULP and have it fixup the ctx. This completes a previous fix that pushed the ops through to the ULP but at the time missed doing this for write_space, presumably because write_space TLS hook was added around the same time. Fixes: 95fa145479fbc ("bpf: sockmap/tls, close can race with map free") Signed-off-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Reviewed-by: Jakub Sitnicki <jakub@cloudflare.com> Acked-by: Jonathan Lemon <jonathan.lemon@gmail.com> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/bpf/20200111061206.8028-4-john.fastabend@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-01-14netfilter: arp_tables: init netns pointer in xt_tgchk_param structFlorian Westphal1-11/+16
commit 1b789577f655060d98d20ed0c6f9fbd469d6ba63 upstream. We get crash when the targets checkentry function tries to make use of the network namespace pointer for arptables. When the net pointer got added back in 2010, only ip/ip6/ebtables were changed to initialize it, so arptables has this set to NULL. This isn't a problem for normal arptables because no existing arptables target has a checkentry function that makes use of par->net. However, direct users of the setsockopt interface can provide any target they want as long as its registered for ARP or UNPSEC protocols. syzkaller managed to send a semi-valid arptables rule for RATEEST target which is enough to trigger NULL deref: kasan: GPF could be caused by NULL-ptr deref or user memory access general protection fault: 0000 [#1] PREEMPT SMP KASAN RIP: xt_rateest_tg_checkentry+0x11d/0xb40 net/netfilter/xt_RATEEST.c:109 [..] xt_check_target+0x283/0x690 net/netfilter/x_tables.c:1019 check_target net/ipv4/netfilter/arp_tables.c:399 [inline] find_check_entry net/ipv4/netfilter/arp_tables.c:422 [inline] translate_table+0x1005/0x1d70 net/ipv4/netfilter/arp_tables.c:572 do_replace net/ipv4/netfilter/arp_tables.c:977 [inline] do_arpt_set_ctl+0x310/0x640 net/ipv4/netfilter/arp_tables.c:1456 Fixes: add67461240c1d ("netfilter: add struct net * to target parameters") Reported-by: syzbot+d7358a458d8a81aee898@syzkaller.appspotmail.com Signed-off-by: Florian Westphal <fw@strlen.de> Acked-by: Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-01-12tcp: fix "old stuff" D-SACK causing SACK to be treated as D-SACKPengcheng Yang1-1/+4
[ Upstream commit c9655008e7845bcfdaac10a1ed8554ec167aea88 ] When we receive a D-SACK, where the sequence number satisfies: undo_marker <= start_seq < end_seq <= prior_snd_una we consider this is a valid D-SACK and tcp_is_sackblock_valid() returns true, then this D-SACK is discarded as "old stuff", but the variable first_sack_index is not marked as negative in tcp_sacktag_write_queue(). If this D-SACK also carries a SACK that needs to be processed (for example, the previous SACK segment was lost), this SACK will be treated as a D-SACK in the following processing of tcp_sacktag_write_queue(), which will eventually lead to incorrect updates of undo_retrans and reordering. Fixes: fd6dad616d4f ("[TCP]: Earlier SACK block verification & simplify access to them") Signed-off-by: Pengcheng Yang <yangpc@wangsu.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-01-09net: annotate lockless accesses to sk->sk_pacing_shiftEric Dumazet2-3/+4
[ Upstream commit 7c68fa2bddda6d942bd387c9ba5b4300737fd991 ] sk->sk_pacing_shift can be read and written without lock synchronization. This patch adds annotations to document this fact and avoid future syzbot complains. This might also avoid unexpected false sharing in sk_pacing_shift_update(), as the compiler could remove the conditional check and always write over sk->sk_pacing_shift : if (sk->sk_pacing_shift != val) sk->sk_pacing_shift = val; Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-01-09tcp: fix data-race in tcp_recvmsg()Eric Dumazet1-8/+6
[ Upstream commit a5a7daa52edb5197a3b696afee13ef174dc2e993 ] Reading tp->recvmsg_inq after socket lock is released raises a KCSAN warning [1] Replace has_tss & has_cmsg by cmsg_flags and make sure to not read tp->recvmsg_inq a second time. [1] BUG: KCSAN: data-race in tcp_chrono_stop / tcp_recvmsg write to 0xffff888126adef24 of 2 bytes by interrupt on cpu 0: tcp_chrono_set net/ipv4/tcp_output.c:2309 [inline] tcp_chrono_stop+0x14c/0x280 net/ipv4/tcp_output.c:2338 tcp_clean_rtx_queue net/ipv4/tcp_input.c:3165 [inline] tcp_ack+0x274f/0x3170 net/ipv4/tcp_input.c:3688 tcp_rcv_established+0x37e/0xf50 net/ipv4/tcp_input.c:5696 tcp_v4_do_rcv+0x381/0x4e0 net/ipv4/tcp_ipv4.c:1561 tcp_v4_rcv+0x19dc/0x1bb0 net/ipv4/tcp_ipv4.c:1942 ip_protocol_deliver_rcu+0x4d/0x420 net/ipv4/ip_input.c:204 ip_local_deliver_finish+0x110/0x140 net/ipv4/ip_input.c:231 NF_HOOK include/linux/netfilter.h:305 [inline] NF_HOOK include/linux/netfilter.h:299 [inline] ip_local_deliver+0x133/0x210 net/ipv4/ip_input.c:252 dst_input include/net/dst.h:442 [inline] ip_rcv_finish+0x121/0x160 net/ipv4/ip_input.c:413 NF_HOOK include/linux/netfilter.h:305 [inline] NF_HOOK include/linux/netfilter.h:299 [inline] ip_rcv+0x18f/0x1a0 net/ipv4/ip_input.c:523 __netif_receive_skb_one_core+0xa7/0xe0 net/core/dev.c:5010 __netif_receive_skb+0x37/0xf0 net/core/dev.c:5124 netif_receive_skb_internal+0x59/0x190 net/core/dev.c:5214 napi_skb_finish net/core/dev.c:5677 [inline] napi_gro_receive+0x28f/0x330 net/core/dev.c:5710 read to 0xffff888126adef25 of 1 bytes by task 7275 on cpu 1: tcp_recvmsg+0x77b/0x1a30 net/ipv4/tcp.c:2187 inet_recvmsg+0xbb/0x250 net/ipv4/af_inet.c:838 sock_recvmsg_nosec net/socket.c:871 [inline] sock_recvmsg net/socket.c:889 [inline] sock_recvmsg+0x92/0xb0 net/socket.c:885 sock_read_iter+0x15f/0x1e0 net/socket.c:967 call_read_iter include/linux/fs.h:1889 [inline] new_sync_read+0x389/0x4f0 fs/read_write.c:414 __vfs_read+0xb1/0xc0 fs/read_write.c:427 vfs_read fs/read_write.c:461 [inline] vfs_read+0x143/0x2c0 fs/read_write.c:446 ksys_read+0xd5/0x1b0 fs/read_write.c:587 __do_sys_read fs/read_write.c:597 [inline] __se_sys_read fs/read_write.c:595 [inline] __x64_sys_read+0x4c/0x60 fs/read_write.c:595 do_syscall_64+0xcc/0x370 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Reported by Kernel Concurrency Sanitizer on: CPU: 1 PID: 7275 Comm: sshd Not tainted 5.4.0-rc3+ #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Fixes: b75eba76d3d7 ("tcp: send in-queue bytes in cmsg upon read") Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Soheil Hassas Yeganeh <soheil@google.com> Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-01-04tcp/dccp: fix possible race __inet_lookup_established()Eric Dumazet3-12/+14
[ Upstream commit 8dbd76e79a16b45b2ccb01d2f2e08dbf64e71e40 ] Michal Kubecek and Firo Yang did a very nice analysis of crashes happening in __inet_lookup_established(). Since a TCP socket can go from TCP_ESTABLISH to TCP_LISTEN (via a close()/socket()/listen() cycle) without a RCU grace period, I should not have changed listeners linkage in their hash table. They must use the nulls protocol (Documentation/RCU/rculist_nulls.txt), so that a lookup can detect a socket in a hash list was moved in another one. Since we added code in commit d296ba60d8e2 ("soreuseport: Resolve merge conflict for v4/v6 ordering fix"), we have to add hlist_nulls_add_tail_rcu() helper. Fixes: 3b24d854cb35 ("tcp/dccp: do not touch listener sk_refcnt under synflood") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Michal Kubecek <mkubecek@suse.cz> Reported-by: Firo Yang <firo.yang@suse.com> Reviewed-by: Michal Kubecek <mkubecek@suse.cz> Link: https://lore.kernel.org/netdev/20191120083919.GH27852@unicorn.suse.cz/ Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-01-04tcp: do not send empty skb from tcp_write_xmit()Eric Dumazet1-0/+8
[ Upstream commit 1f85e6267caca44b30c54711652b0726fadbb131 ] Backport of commit fdfc5c8594c2 ("tcp: remove empty skb from write queue in error cases") in linux-4.14 stable triggered various bugs. One of them has been fixed in commit ba2ddb43f270 ("tcp: Don't dequeue SYN/FIN-segments from write-queue"), but we still have crashes in some occasions. Root-cause is that when tcp_sendmsg() has allocated a fresh skb and could not append a fragment before being blocked in sk_stream_wait_memory(), tcp_write_xmit() might be called and decide to send this fresh and empty skb. Sending an empty packet is not only silly, it might have caused many issues we had in the past with tp->packets_out being out of sync. Fixes: c65f7f00c587 ("[TCP]: Simplify SKB data portion allocation with NETIF_F_SG.") Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Christoph Paasch <cpaasch@apple.com> Acked-by: Neal Cardwell <ncardwell@google.com> Cc: Jason Baron <jbaron@akamai.com> Acked-by: Soheil Hassas Yeganeh <soheil@google.com> Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-01-04vti: do not confirm neighbor when do pmtu updateHangbin Liu1-1/+1
[ Upstream commit 8247a79efa2f28b44329f363272550c1738377de ] When do IPv6 tunnel PMTU update and calls __ip6_rt_update_pmtu() in the end, we should not call dst_confirm_neigh() as there is no two-way communication. Although vti and vti6 are immune to this problem because they are IFF_NOARP interfaces, as Guillaume pointed. There is still no sense to confirm neighbour here. v5: Update commit description. v4: No change. v3: Do not remove dst_confirm_neigh, but add a new bool parameter in dst_ops.update_pmtu to control whether we should do neighbor confirm. Also split the big patch to small ones for each area. v2: Remove dst_confirm_neigh in __ip6_rt_update_pmtu. Reviewed-by: Guillaume Nault <gnault@redhat.com> Acked-by: David Ahern <dsahern@gmail.com> Signed-off-by: Hangbin Liu <liuhangbin@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-01-04tunnel: do not confirm neighbor when do pmtu updateHangbin Liu1-1/+1
[ Upstream commit 7a1592bcb15d71400a98632727791d1e68ea0ee8 ] When do tunnel PMTU update and calls __ip6_rt_update_pmtu() in the end, we should not call dst_confirm_neigh() as there is no two-way communication. v5: No Change. v4: Update commit description v3: Do not remove dst_confirm_neigh, but add a new bool parameter in dst_ops.update_pmtu to control whether we should do neighbor confirm. Also split the big patch to small ones for each area. v2: Remove dst_confirm_neigh in __ip6_rt_update_pmtu. Fixes: 0dec879f636f ("net: use dst_confirm_neigh for UDP, RAW, ICMP, L2TP") Reviewed-by: Guillaume Nault <gnault@redhat.com> Tested-by: Guillaume Nault <gnault@redhat.com> Acked-by: David Ahern <dsahern@gmail.com> Signed-off-by: Hangbin Liu <liuhangbin@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-01-04net: add bool confirm_neigh parameter for dst_ops.update_pmtuHangbin Liu3-6/+10
[ Upstream commit bd085ef678b2cc8c38c105673dfe8ff8f5ec0c57 ] The MTU update code is supposed to be invoked in response to real networking events that update the PMTU. In IPv6 PMTU update function __ip6_rt_update_pmtu() we called dst_confirm_neigh() to update neighbor confirmed time. But for tunnel code, it will call pmtu before xmit, like: - tnl_update_pmtu() - skb_dst_update_pmtu() - ip6_rt_update_pmtu() - __ip6_rt_update_pmtu() - dst_confirm_neigh() If the tunnel remote dst mac address changed and we still do the neigh confirm, we will not be able to update neigh cache and ping6 remote will failed. So for this ip_tunnel_xmit() case, _EVEN_ if the MTU is changed, we should not be invoking dst_confirm_neigh() as we have no evidence of successful two-way communication at this point. On the other hand it is also important to keep the neigh reachability fresh for TCP flows, so we cannot remove this dst_confirm_neigh() call. To fix the issue, we have to add a new bool parameter for dst_ops.update_pmtu to choose whether we should do neigh update or not. I will add the parameter in this patch and set all the callers to true to comply with the previous way, and fix the tunnel code one by one on later patches. v5: No change. v4: No change. v3: Do not remove dst_confirm_neigh, but add a new bool parameter in dst_ops.update_pmtu to control whether we should do neighbor confirm. Also split the big patch to small ones for each area. v2: Remove dst_confirm_neigh in __ip6_rt_update_pmtu. Suggested-by: David Miller <davem@davemloft.net> Reviewed-by: Guillaume Nault <gnault@redhat.com> Acked-by: David Ahern <dsahern@gmail.com> Signed-off-by: Hangbin Liu <liuhangbin@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-01-04udp: fix integer overflow while computing available space in sk_rcvbufAntonio Messina1-1/+1
[ Upstream commit feed8a4fc9d46c3126fb9fcae0e9248270c6321a ] When the size of the receive buffer for a socket is close to 2^31 when computing if we have enough space in the buffer to copy a packet from the queue to the buffer we might hit an integer overflow. When an user set net.core.rmem_default to a value close to 2^31 UDP packets are dropped because of this overflow. This can be visible, for instance, with failure to resolve hostnames. This can be fixed by casting sk_rcvbuf (which is an int) to unsigned int, similarly to how it is done in TCP. Signed-off-by: Antonio Messina <amessina@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-01-04tcp: Fix highest_sack and highest_sack_seqCambda Zhu1-0/+3
[ Upstream commit 853697504de043ff0bfd815bd3a64de1dce73dc7 ] >From commit 50895b9de1d3 ("tcp: highest_sack fix"), the logic about setting tp->highest_sack to the head of the send queue was removed. Of course the logic is error prone, but it is logical. Before we remove the pointer to the highest sack skb and use the seq instead, we need to set tp->highest_sack to NULL when there is no skb after the last sack, and then replace NULL with the real skb when new skb inserted into the rtx queue, because the NULL means the highest sack seq is tp->snd_nxt. If tp->highest_sack is NULL and new data sent, the next ACK with sack option will increase tp->reordering unexpectedly. This patch sets tp->highest_sack to the tail of the rtx queue if it's NULL and new data is sent. The patch keeps the rule that the highest_sack can only be maintained by sack processing, except for this only case. Fixes: 50895b9de1d3 ("tcp: highest_sack fix") Signed-off-by: Cambda Zhu <cambda@linux.alibaba.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-01-04net: icmp: fix data-race in cmp_global_allow()Eric Dumazet1-5/+6
commit bbab7ef235031f6733b5429ae7877bfa22339712 upstream. This code reads two global variables without protection of a lock. We need READ_ONCE()/WRITE_ONCE() pairs to avoid load/store-tearing and better document the intent. KCSAN reported : BUG: KCSAN: data-race in icmp_global_allow / icmp_global_allow read to 0xffffffff861a8014 of 4 bytes by task 11201 on cpu 0: icmp_global_allow+0x36/0x1b0 net/ipv4/icmp.c:254 icmpv6_global_allow net/ipv6/icmp.c:184 [inline] icmpv6_global_allow net/ipv6/icmp.c:179 [inline] icmp6_send+0x493/0x1140 net/ipv6/icmp.c:514 icmpv6_send+0x71/0xb0 net/ipv6/ip6_icmp.c:43 ip6_link_failure+0x43/0x180 net/ipv6/route.c:2640 dst_link_failure include/net/dst.h:419 [inline] vti_xmit net/ipv4/ip_vti.c:243 [inline] vti_tunnel_xmit+0x27f/0xa50 net/ipv4/ip_vti.c:279 __netdev_start_xmit include/linux/netdevice.h:4420 [inline] netdev_start_xmit include/linux/netdevice.h:4434 [inline] xmit_one net/core/dev.c:3280 [inline] dev_hard_start_xmit+0xef/0x430 net/core/dev.c:3296 __dev_queue_xmit+0x14c9/0x1b60 net/core/dev.c:3873 dev_queue_xmit+0x21/0x30 net/core/dev.c:3906 neigh_direct_output+0x1f/0x30 net/core/neighbour.c:1530 neigh_output include/net/neighbour.h:511 [inline] ip6_finish_output2+0x7a6/0xec0 net/ipv6/ip6_output.c:116 __ip6_finish_output net/ipv6/ip6_output.c:142 [inline] __ip6_finish_output+0x2d7/0x330 net/ipv6/ip6_output.c:127 ip6_finish_output+0x41/0x160 net/ipv6/ip6_output.c:152 NF_HOOK_COND include/linux/netfilter.h:294 [inline] ip6_output+0xf2/0x280 net/ipv6/ip6_output.c:175 dst_output include/net/dst.h:436 [inline] ip6_local_out+0x74/0x90 net/ipv6/output_core.c:179 write to 0xffffffff861a8014 of 4 bytes by task 11183 on cpu 1: icmp_global_allow+0x174/0x1b0 net/ipv4/icmp.c:272 icmpv6_global_allow net/ipv6/icmp.c:184 [inline] icmpv6_global_allow net/ipv6/icmp.c:179 [inline] icmp6_send+0x493/0x1140 net/ipv6/icmp.c:514 icmpv6_send+0x71/0xb0 net/ipv6/ip6_icmp.c:43 ip6_link_failure+0x43/0x180 net/ipv6/route.c:2640 dst_link_failure include/net/dst.h:419 [inline] vti_xmit net/ipv4/ip_vti.c:243 [inline] vti_tunnel_xmit+0x27f/0xa50 net/ipv4/ip_vti.c:279 __netdev_start_xmit include/linux/netdevice.h:4420 [inline] netdev_start_xmit include/linux/netdevice.h:4434 [inline] xmit_one net/core/dev.c:3280 [inline] dev_hard_start_xmit+0xef/0x430 net/core/dev.c:3296 __dev_queue_xmit+0x14c9/0x1b60 net/core/dev.c:3873 dev_queue_xmit+0x21/0x30 net/core/dev.c:3906 neigh_direct_output+0x1f/0x30 net/core/neighbour.c:1530 neigh_output include/net/neighbour.h:511 [inline] ip6_finish_output2+0x7a6/0xec0 net/ipv6/ip6_output.c:116 __ip6_finish_output net/ipv6/ip6_output.c:142 [inline] __ip6_finish_output+0x2d7/0x330 net/ipv6/ip6_output.c:127 ip6_finish_output+0x41/0x160 net/ipv6/ip6_output.c:152 NF_HOOK_COND include/linux/netfilter.h:294 [inline] ip6_output+0xf2/0x280 net/ipv6/ip6_output.c:175 Reported by Kernel Concurrency Sanitizer on: CPU: 1 PID: 11183 Comm: syz-executor.2 Not tainted 5.4.0-rc3+ #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Fixes: 4cdf507d5452 ("icmp: add a global rate limitation") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-01-04inetpeer: fix data-race in inet_putpeer / inet_putpeerEric Dumazet1-2/+10
commit 71685eb4ce80ae9c49eff82ca4dd15acab215de9 upstream. We need to explicitely forbid read/store tearing in inet_peer_gc() and inet_putpeer(). The following syzbot report reminds us about inet_putpeer() running without a lock held. BUG: KCSAN: data-race in inet_putpeer / inet_putpeer write to 0xffff888121fb2ed0 of 4 bytes by interrupt on cpu 0: inet_putpeer+0x37/0xa0 net/ipv4/inetpeer.c:240 ip4_frag_free+0x3d/0x50 net/ipv4/ip_fragment.c:102 inet_frag_destroy_rcu+0x58/0x80 net/ipv4/inet_fragment.c:228 __rcu_reclaim kernel/rcu/rcu.h:222 [inline] rcu_do_batch+0x256/0x5b0 kernel/rcu/tree.c:2157 rcu_core+0x369/0x4d0 kernel/rcu/tree.c:2377 rcu_core_si+0x12/0x20 kernel/rcu/tree.c:2386 __do_softirq+0x115/0x33f kernel/softirq.c:292 invoke_softirq kernel/softirq.c:373 [inline] irq_exit+0xbb/0xe0 kernel/softirq.c:413 exiting_irq arch/x86/include/asm/apic.h:536 [inline] smp_apic_timer_interrupt+0xe6/0x280 arch/x86/kernel/apic/apic.c:1137 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:830 native_safe_halt+0xe/0x10 arch/x86/kernel/paravirt.c:71 arch_cpu_idle+0x1f/0x30 arch/x86/kernel/process.c:571 default_idle_call+0x1e/0x40 kernel/sched/idle.c:94 cpuidle_idle_call kernel/sched/idle.c:154 [inline] do_idle+0x1af/0x280 kernel/sched/idle.c:263 write to 0xffff888121fb2ed0 of 4 bytes by interrupt on cpu 1: inet_putpeer+0x37/0xa0 net/ipv4/inetpeer.c:240 ip4_frag_free+0x3d/0x50 net/ipv4/ip_fragment.c:102 inet_frag_destroy_rcu+0x58/0x80 net/ipv4/inet_fragment.c:228 __rcu_reclaim kernel/rcu/rcu.h:222 [inline] rcu_do_batch+0x256/0x5b0 kernel/rcu/tree.c:2157 rcu_core+0x369/0x4d0 kernel/rcu/tree.c:2377 rcu_core_si+0x12/0x20 kernel/rcu/tree.c:2386 __do_softirq+0x115/0x33f kernel/softirq.c:292 run_ksoftirqd+0x46/0x60 kernel/softirq.c:603 smpboot_thread_fn+0x37d/0x4a0 kernel/smpboot.c:165 kthread+0x1d4/0x200 drivers/block/aoe/aoecmd.c:1253 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:352 Reported by Kernel Concurrency Sanitizer on: CPU: 1 PID: 16 Comm: ksoftirqd/1 Not tainted 5.4.0-rc3+ #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Fixes: 4b9d9be839fd ("inetpeer: remove unused list") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-12-18gre: refetch erspan header from skb->data after pskb_may_pull()Cong Wang1-1/+1
[ Upstream commit 0e4940928c26527ce8f97237fef4c8a91cd34207 ] After pskb_may_pull() we should always refetch the header pointers from the skb->data in case it got reallocated. In gre_parse_header(), the erspan header is still fetched from the 'options' pointer which is fetched before pskb_may_pull(). Found this during code review of a KMSAN bug report. Fixes: cb73ee40b1b3 ("net: ip_gre: use erspan key field for tunnel lookup") Cc: Lorenzo Bianconi <lorenzo.bianconi@redhat.com> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Acked-by: Lorenzo Bianconi <lorenzo.bianconi@redhat.com> Acked-by: William Tu <u9012063@gmail.com> Reviewed-by: Simon Horman <simon.horman@netronome.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-12-18tcp: md5: fix potential overestimation of TCP option spaceEric Dumazet1-2/+3
[ Upstream commit 9424e2e7ad93ffffa88f882c9bc5023570904b55 ] Back in 2008, Adam Langley fixed the corner case of packets for flows having all of the following options : MD5 TS SACK Since MD5 needs 20 bytes, and TS needs 12 bytes, no sack block can be cooked from the remaining 8 bytes. tcp_established_options() correctly sets opts->num_sack_blocks to zero, but returns 36 instead of 32. This means TCP cooks packets with 4 extra bytes at the end of options, containing unitialized bytes. Fixes: 33ad798c924b ("tcp: options clean up") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: syzbot <syzkaller@googlegroups.com> Acked-by: Neal Cardwell <ncardwell@google.com> Acked-by: Soheil Hassas Yeganeh <soheil@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-12-18inet: protect against too small mtu values.Eric Dumazet2-10/+8
[ Upstream commit 501a90c945103e8627406763dac418f20f3837b2 ] syzbot was once again able to crash a host by setting a very small mtu on loopback device. Let's make inetdev_valid_mtu() available in include/net/ip.h, and use it in ip_setup_cork(), so that we protect both ip_append_page() and __ip_append_data() Also add a READ_ONCE() when the device mtu is read. Pairs this lockless read with one WRITE_ONCE() in __dev_set_mtu(), even if other code paths might write over this field. Add a big comment in include/linux/netdevice.h about dev->mtu needing READ_ONCE()/WRITE_ONCE() annotations. Hopefully we will add the missing ones in followup patches. [1] refcount_t: saturated; leaking memory. WARNING: CPU: 0 PID: 9464 at lib/refcount.c:22 refcount_warn_saturate+0x138/0x1f0 lib/refcount.c:22 Kernel panic - not syncing: panic_on_warn set ... CPU: 0 PID: 9464 Comm: syz-executor850 Not tainted 5.4.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x197/0x210 lib/dump_stack.c:118 panic+0x2e3/0x75c kernel/panic.c:221 __warn.cold+0x2f/0x3e kernel/panic.c:582 report_bug+0x289/0x300 lib/bug.c:195 fixup_bug arch/x86/kernel/traps.c:174 [inline] fixup_bug arch/x86/kernel/traps.c:169 [inline] do_error_trap+0x11b/0x200 arch/x86/kernel/traps.c:267 do_invalid_op+0x37/0x50 arch/x86/kernel/traps.c:286 invalid_op+0x23/0x30 arch/x86/entry/entry_64.S:1027 RIP: 0010:refcount_warn_saturate+0x138/0x1f0 lib/refcount.c:22 Code: 06 31 ff 89 de e8 c8 f5 e6 fd 84 db 0f 85 6f ff ff ff e8 7b f4 e6 fd 48 c7 c7 e0 71 4f 88 c6 05 56 a6 a4 06 01 e8 c7 a8 b7 fd <0f> 0b e9 50 ff ff ff e8 5c f4 e6 fd 0f b6 1d 3d a6 a4 06 31 ff 89 RSP: 0018:ffff88809689f550 EFLAGS: 00010286 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000 RDX: 0000000000000000 RSI: ffffffff815e4336 RDI: ffffed1012d13e9c RBP: ffff88809689f560 R08: ffff88809c50a3c0 R09: fffffbfff15d31b1 R10: fffffbfff15d31b0 R11: ffffffff8ae98d87 R12: 0000000000000001 R13: 0000000000040100 R14: ffff888099041104 R15: ffff888218d96e40 refcount_add include/linux/refcount.h:193 [inline] skb_set_owner_w+0x2b6/0x410 net/core/sock.c:1999 sock_wmalloc+0xf1/0x120 net/core/sock.c:2096 ip_append_page+0x7ef/0x1190 net/ipv4/ip_output.c:1383 udp_sendpage+0x1c7/0x480 net/ipv4/udp.c:1276 inet_sendpage+0xdb/0x150 net/ipv4/af_inet.c:821 kernel_sendpage+0x92/0xf0 net/socket.c:3794 sock_sendpage+0x8b/0xc0 net/socket.c:936 pipe_to_sendpage+0x2da/0x3c0 fs/splice.c:458 splice_from_pipe_feed fs/splice.c:512 [inline] __splice_from_pipe+0x3ee/0x7c0 fs/splice.c:636 splice_from_pipe+0x108/0x170 fs/splice.c:671 generic_splice_sendpage+0x3c/0x50 fs/splice.c:842 do_splice_from fs/splice.c:861 [inline] direct_splice_actor+0x123/0x190 fs/splice.c:1035 splice_direct_to_actor+0x3b4/0xa30 fs/splice.c:990 do_splice_direct+0x1da/0x2a0 fs/splice.c:1078 do_sendfile+0x597/0xd00 fs/read_write.c:1464 __do_sys_sendfile64 fs/read_write.c:1525 [inline] __se_sys_sendfile64 fs/read_write.c:1511 [inline] __x64_sys_sendfile64+0x1dd/0x220 fs/read_write.c:1511 do_syscall_64+0xfa/0x790 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x441409 Code: e8 ac e8 ff ff 48 83 c4 18 c3 0f 1f 80 00 00 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 eb 08 fc ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007fffb64c4f78 EFLAGS: 00000246 ORIG_RAX: 0000000000000028 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000441409 RDX: 0000000000000000 RSI: 0000000000000006 RDI: 0000000000000005 RBP: 0000000000073b8a R08: 0000000000000010 R09: 0000000000000010 R10: 0000000000010001 R11: 0000000000000246 R12: 0000000000402180 R13: 0000000000402210 R14: 0000000000000000 R15: 0000000000000000 Kernel Offset: disabled Rebooting in 86400 seconds.. Fixes: 1470ddf7f8ce ("inet: Remove explicit write references to sk/inet in ip_append_data") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-12-05net: skmsg: fix TLS 1.3 crash with full sk_msgJakub Kicinski1-1/+1
[ Upstream commit 031097d9e079e40dce401031d1012e83d80eaf01 ] TLS 1.3 started using the entry at the end of the SG array for chaining-in the single byte content type entry. This mostly works: [ E E E E E E . . ] ^ ^ start end E < content type / [ E E E E E E C . ] ^ ^ start end (Where E denotes a populated SG entry; C denotes a chaining entry.) If the array is full, however, the end will point to the start: [ E E E E E E E E ] ^ start end And we end up overwriting the start: E < content type / [ C E E E E E E E ] ^ start end The sg array is supposed to be a circular buffer with start and end markers pointing anywhere. In case where start > end (i.e. the circular buffer has "wrapped") there is an extra entry reserved at the end to chain the two halves together. [ E E E E E E . . l ] (Where l is the reserved entry for "looping" back to front. As suggested by John, let's reserve another entry for chaining SG entries after the main circular buffer. Note that this entry has to be pointed to by the end entry so its position is not fixed. Examples of full messages: [ E E E E E E E E . l ] ^ ^ start end <---------------. [ E E . E E E E E E l ] ^ ^ end start Now the end will always point to an unused entry, so TLS 1.3 can always use it. Fixes: 130b392c6cd6 ("net: tls: Add tls 1.3 support") Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com> Reviewed-by: Simon Horman <simon.horman@netronome.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-11-22udp: drop skb extensions before marking skb statelessFlorian Westphal1-5/+22
Once udp stack has set the UDP_SKB_IS_STATELESS flag, later skb free assumes all skb head state has been dropped already. This will leak the extension memory in case the skb has extensions other than the ipsec secpath, e.g. bridge nf data. To fix this, set the UDP_SKB_IS_STATELESS flag only if we don't have extensions or if the extension space can be free'd. Fixes: 895b5c9f206eb7d25dc1360a ("netfilter: drop bridge nf reset from nf_reset") Cc: Paolo Abeni <pabeni@redhat.com> Reported-by: Byron Stanoszek <gandalf@winds.org> Signed-off-by: Florian Westphal <fw@strlen.de> Acked-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-11-19net/ipv4: fix sysctl max for fib_multipath_hash_policyMarcelo Ricardo Leitner1-1/+1
Commit eec4844fae7c ("proc/sysctl: add shared variables for range check") did: - .extra2 = &two, + .extra2 = SYSCTL_ONE, here, which doesn't seem to be intentional, given the changelog. This patch restores it to the previous, as the value of 2 still makes sense (used in fib_multipath_hash()). Fixes: eec4844fae7c ("proc/sysctl: add shared variables for range check") Cc: Matteo Croce <mcroce@redhat.com> Signed-off-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Acked-by: Matteo Croce <mcroce@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-11-17ipmr: Fix skb headroom in ipmr_get_route().Guillaume Nault1-1/+2
In route.c, inet_rtm_getroute_build_skb() creates an skb with no headroom. This skb is then used by inet_rtm_getroute() which may pass it to rt_fill_info() and, from there, to ipmr_get_route(). The later might try to reuse this skb by cloning it and prepending an IPv4 header. But since the original skb has no headroom, skb_push() triggers skb_under_panic(): skbuff: skb_under_panic: text:00000000ca46ad8a len:80 put:20 head:00000000cd28494e data:000000009366fd6b tail:0x3c end:0xec0 dev:veth0 ------------[ cut here ]------------ kernel BUG at net/core/skbuff.c:108! invalid opcode: 0000 [#1] SMP KASAN PTI CPU: 6 PID: 587 Comm: ip Not tainted 5.4.0-rc6+ #1 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-2.fc30 04/01/2014 RIP: 0010:skb_panic+0xbf/0xd0 Code: 41 a2 ff 8b 4b 70 4c 8b 4d d0 48 c7 c7 20 76 f5 8b 44 8b 45 bc 48 8b 55 c0 48 8b 75 c8 41 54 41 57 41 56 41 55 e8 75 dc 7a ff <0f> 0b 0f 1f 44 00 00 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 RSP: 0018:ffff888059ddf0b0 EFLAGS: 00010286 RAX: 0000000000000086 RBX: ffff888060a315c0 RCX: ffffffff8abe4822 RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffff88806c9a79cc RBP: ffff888059ddf118 R08: ffffed100d9361b1 R09: ffffed100d9361b0 R10: ffff88805c68aee3 R11: ffffed100d9361b1 R12: ffff88805d218000 R13: ffff88805c689fec R14: 000000000000003c R15: 0000000000000ec0 FS: 00007f6af184b700(0000) GS:ffff88806c980000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ffc8204a000 CR3: 0000000057b40006 CR4: 0000000000360ee0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: skb_push+0x7e/0x80 ipmr_get_route+0x459/0x6fa rt_fill_info+0x692/0x9f0 inet_rtm_getroute+0xd26/0xf20 rtnetlink_rcv_msg+0x45d/0x630 netlink_rcv_skb+0x1a5/0x220 rtnetlink_rcv+0x15/0x20 netlink_unicast+0x305/0x3a0 netlink_sendmsg+0x575/0x730 sock_sendmsg+0xb5/0xc0 ___sys_sendmsg+0x497/0x4f0 __sys_sendmsg+0xcb/0x150 __x64_sys_sendmsg+0x48/0x50 do_syscall_64+0xd2/0xac0 entry_SYSCALL_64_after_hwframe+0x49/0xbe Actually the original skb used to have enough headroom, but the reserve_skb() call was lost with the introduction of inet_rtm_getroute_build_skb() by commit 404eb77ea766 ("ipv4: support sport, dport and ip_proto in RTM_GETROUTE"). We could reserve some headroom again in inet_rtm_getroute_build_skb(), but this function shouldn't be responsible for handling the special case of ipmr_get_route(). Let's handle that directly in ipmr_get_route() by calling skb_realloc_headroom() instead of skb_clone(). Fixes: 404eb77ea766 ("ipv4: support sport, dport and ip_proto in RTM_GETROUTE") Signed-off-by: Guillaume Nault <gnault@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-11-08ipv4: Fix table id reference in fib_sync_down_addrDavid Ahern1-1/+1
Hendrik reported routes in the main table using source address are not removed when the address is removed. The problem is that fib_sync_down_addr does not account for devices in the default VRF which are associated with the main table. Fix by updating the table id reference. Fixes: 5a56a0b3a45d ("net: Don't delete routes in different VRFs") Reported-by: Hendrik Donner <hd@os-cillation.de> Signed-off-by: David Ahern <dsahern@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-11-02inet: stop leaking jiffies on the wireEric Dumazet2-3/+3
Historically linux tried to stick to RFC 791, 1122, 2003 for IPv4 ID field generation. RFC 6864 made clear that no matter how hard we try, we can not ensure unicity of IP ID within maximum lifetime for all datagrams with a given source address/destination address/protocol tuple. Linux uses a per socket inet generator (inet_id), initialized at connection startup with a XOR of 'jiffies' and other fields that appear clear on the wire. Thiemo Nagel pointed that this strategy is a privacy concern as this provides 16 bits of entropy to fingerprint devices. Let's switch to a random starting point, this is just as good as far as RFC 6864 is concerned and does not leak anything critical. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Thiemo Nagel <tnagel@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-11-01tcp: increase tcp_max_syn_backlog max valueEric Dumazet1-1/+1
tcp_max_syn_backlog default value depends on memory size and TCP ehash size. Before this patch, the max value was 2048 [1], which is considered too small nowadays. Increase it to 4096 to match the recent SOMAXCONN change. [1] This is with TCP ehash size being capped to 524288 buckets. Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Willy Tarreau <w@1wt.eu> Cc: Yue Cao <ycao009@ucr.edu> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-30net: annotate accesses to sk->sk_incoming_cpuEric Dumazet2-2/+2
This socket field can be read and written by concurrent cpus. Use READ_ONCE() and WRITE_ONCE() annotations to document this, and avoid some compiler 'optimizations'. KCSAN reported : BUG: KCSAN: data-race in tcp_v4_rcv / tcp_v4_rcv write to 0xffff88812220763c of 4 bytes by interrupt on cpu 0: sk_incoming_cpu_update include/net/sock.h:953 [inline] tcp_v4_rcv+0x1b3c/0x1bb0 net/ipv4/tcp_ipv4.c:1934 ip_protocol_deliver_rcu+0x4d/0x420 net/ipv4/ip_input.c:204 ip_local_deliver_finish+0x110/0x140 net/ipv4/ip_input.c:231 NF_HOOK include/linux/netfilter.h:305 [inline] NF_HOOK include/linux/netfilter.h:299 [inline] ip_local_deliver+0x133/0x210 net/ipv4/ip_input.c:252 dst_input include/net/dst.h:442 [inline] ip_rcv_finish+0x121/0x160 net/ipv4/ip_input.c:413 NF_HOOK include/linux/netfilter.h:305 [inline] NF_HOOK include/linux/netfilter.h:299 [inline] ip_rcv+0x18f/0x1a0 net/ipv4/ip_input.c:523 __netif_receive_skb_one_core+0xa7/0xe0 net/core/dev.c:5010 __netif_receive_skb+0x37/0xf0 net/core/dev.c:5124 process_backlog+0x1d3/0x420 net/core/dev.c:5955 napi_poll net/core/dev.c:6392 [inline] net_rx_action+0x3ae/0xa90 net/core/dev.c:6460 __do_softirq+0x115/0x33f kernel/softirq.c:292 do_softirq_own_stack+0x2a/0x40 arch/x86/entry/entry_64.S:1082 do_softirq.part.0+0x6b/0x80 kernel/softirq.c:337 do_softirq kernel/softirq.c:329 [inline] __local_bh_enable_ip+0x76/0x80 kernel/softirq.c:189 read to 0xffff88812220763c of 4 bytes by interrupt on cpu 1: sk_incoming_cpu_update include/net/sock.h:952 [inline] tcp_v4_rcv+0x181a/0x1bb0 net/ipv4/tcp_ipv4.c:1934 ip_protocol_deliver_rcu+0x4d/0x420 net/ipv4/ip_input.c:204 ip_local_deliver_finish+0x110/0x140 net/ipv4/ip_input.c:231 NF_HOOK include/linux/netfilter.h:305 [inline] NF_HOOK include/linux/netfilter.h:299 [inline] ip_local_deliver+0x133/0x210 net/ipv4/ip_input.c:252 dst_input include/net/dst.h:442 [inline] ip_rcv_finish+0x121/0x160 net/ipv4/ip_input.c:413 NF_HOOK include/linux/netfilter.h:305 [inline] NF_HOOK include/linux/netfilter.h:299 [inline] ip_rcv+0x18f/0x1a0 net/ipv4/ip_input.c:523 __netif_receive_skb_one_core+0xa7/0xe0 net/core/dev.c:5010 __netif_receive_skb+0x37/0xf0 net/core/dev.c:5124 process_backlog+0x1d3/0x420 net/core/dev.c:5955 napi_poll net/core/dev.c:6392 [inline] net_rx_action+0x3ae/0xa90 net/core/dev.c:6460 __do_softirq+0x115/0x33f kernel/softirq.c:292 run_ksoftirqd+0x46/0x60 kernel/softirq.c:603 smpboot_thread_fn+0x37d/0x4a0 kernel/smpboot.c:165 Reported by Kernel Concurrency Sanitizer on: CPU: 1 PID: 16 Comm: ksoftirqd/1 Not tainted 5.4.0-rc3+ #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-30erspan: fix the tun_info options_len check for erspanXin Long1-2/+2
The check for !md doens't really work for ip_tunnel_info_opts(info) which only does info + 1. Also to avoid out-of-bounds access on info, it should ensure options_len is not less than erspan_metadata in both erspan_xmit() and ip6erspan_tunnel_xmit(). Fixes: 1a66a836da ("gre: add collect_md mode to ERSPAN tunnel") Signed-off-by: Xin Long <lucien.xin@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-28udp: fix data-race in udp_set_dev_scratch()Eric Dumazet1-4/+15
KCSAN reported a data-race in udp_set_dev_scratch() [1] The issue here is that we must not write over skb fields if skb is shared. A similar issue has been fixed in commit 89c22d8c3b27 ("net: Fix skb csum races when peeking") While we are at it, use a helper only dealing with udp_skb_scratch(skb)->csum_unnecessary, as this allows udp_set_dev_scratch() to be called once and thus inlined. [1] BUG: KCSAN: data-race in udp_set_dev_scratch / udpv6_recvmsg write to 0xffff888120278317 of 1 bytes by task 10411 on cpu 1: udp_set_dev_scratch+0xea/0x200 net/ipv4/udp.c:1308 __first_packet_length+0x147/0x420 net/ipv4/udp.c:1556 first_packet_length+0x68/0x2a0 net/ipv4/udp.c:1579 udp_poll+0xea/0x110 net/ipv4/udp.c:2720 sock_poll+0xed/0x250 net/socket.c:1256 vfs_poll include/linux/poll.h:90 [inline] do_select+0x7d0/0x1020 fs/select.c:534 core_sys_select+0x381/0x550 fs/select.c:677 do_pselect.constprop.0+0x11d/0x160 fs/select.c:759 __do_sys_pselect6 fs/select.c:784 [inline] __se_sys_pselect6 fs/select.c:769 [inline] __x64_sys_pselect6+0x12e/0x170 fs/select.c:769 do_syscall_64+0xcc/0x370 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x44/0xa9 read to 0xffff888120278317 of 1 bytes by task 10413 on cpu 0: udp_skb_csum_unnecessary include/net/udp.h:358 [inline] udpv6_recvmsg+0x43e/0xe90 net/ipv6/udp.c:310 inet6_recvmsg+0xbb/0x240 net/ipv6/af_inet6.c:592 sock_recvmsg_nosec+0x5c/0x70 net/socket.c:871 ___sys_recvmsg+0x1a0/0x3e0 net/socket.c:2480 do_recvmmsg+0x19a/0x5c0 net/socket.c:2601 __sys_recvmmsg+0x1ef/0x200 net/socket.c:2680 __do_sys_recvmmsg net/socket.c:2703 [inline] __se_sys_recvmmsg net/socket.c:2696 [inline] __x64_sys_recvmmsg+0x89/0xb0 net/socket.c:2696 do_syscall_64+0xcc/0x370 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Reported by Kernel Concurrency Sanitizer on: CPU: 0 PID: 10413 Comm: syz-executor.0 Not tainted 5.4.0-rc3+ #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Fixes: 2276f58ac589 ("udp: use a separate rx queue for packet reception") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: syzbot <syzkaller@googlegroups.com> Cc: Paolo Abeni <pabeni@redhat.com> Reviewed-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-28net: use skb_queue_empty_lockless() in busy poll contextsEric Dumazet1-1/+1
Busy polling usually runs without locks. Let's use skb_queue_empty_lockless() instead of skb_queue_empty() Also uses READ_ONCE() in __skb_try_recv_datagram() to address a similar potential problem. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-28net: use skb_queue_empty_lockless() in poll() handlersEric Dumazet2-2/+2
Many poll() handlers are lockless. Using skb_queue_empty_lockless() instead of skb_queue_empty() is more appropriate. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-28udp: use skb_queue_empty_lockless()Eric Dumazet1-3/+3
syzbot reported a data-race [1]. We should use skb_queue_empty_lockless() to document that we are not ensuring a mutual exclusion and silence KCSAN. [1] BUG: KCSAN: data-race in __skb_recv_udp / __udp_enqueue_schedule_skb write to 0xffff888122474b50 of 8 bytes by interrupt on cpu 0: __skb_insert include/linux/skbuff.h:1852 [inline] __skb_queue_before include/linux/skbuff.h:1958 [inline] __skb_queue_tail include/linux/skbuff.h:1991 [inline] __udp_enqueue_schedule_skb+0x2c1/0x410 net/ipv4/udp.c:1470 __udp_queue_rcv_skb net/ipv4/udp.c:1940 [inline] udp_queue_rcv_one_skb+0x7bd/0xc70 net/ipv4/udp.c:2057 udp_queue_rcv_skb+0xb5/0x400 net/ipv4/udp.c:2074 udp_unicast_rcv_skb.isra.0+0x7e/0x1c0 net/ipv4/udp.c:2233 __udp4_lib_rcv+0xa44/0x17c0 net/ipv4/udp.c:2300 udp_rcv+0x2b/0x40 net/ipv4/udp.c:2470 ip_protocol_deliver_rcu+0x4d/0x420 net/ipv4/ip_input.c:204 ip_local_deliver_finish+0x110/0x140 net/ipv4/ip_input.c:231 NF_HOOK include/linux/netfilter.h:305 [inline] NF_HOOK include/linux/netfilter.h:299 [inline] ip_local_deliver+0x133/0x210 net/ipv4/ip_input.c:252 dst_input include/net/dst.h:442 [inline] ip_rcv_finish+0x121/0x160 net/ipv4/ip_input.c:413 NF_HOOK include/linux/netfilter.h:305 [inline] NF_HOOK include/linux/netfilter.h:299 [inline] ip_rcv+0x18f/0x1a0 net/ipv4/ip_input.c:523 __netif_receive_skb_one_core+0xa7/0xe0 net/core/dev.c:5010 __netif_receive_skb+0x37/0xf0 net/core/dev.c:5124 process_backlog+0x1d3/0x420 net/core/dev.c:5955 read to 0xffff888122474b50 of 8 bytes by task 8921 on cpu 1: skb_queue_empty include/linux/skbuff.h:1494 [inline] __skb_recv_udp+0x18d/0x500 net/ipv4/udp.c:1653 udp_recvmsg+0xe1/0xb10 net/ipv4/udp.c:1712 inet_recvmsg+0xbb/0x250 net/ipv4/af_inet.c:838 sock_recvmsg_nosec+0x5c/0x70 net/socket.c:871 ___sys_recvmsg+0x1a0/0x3e0 net/socket.c:2480 do_recvmmsg+0x19a/0x5c0 net/socket.c:2601 __sys_recvmmsg+0x1ef/0x200 net/socket.c:2680 __do_sys_recvmmsg net/socket.c:2703 [inline] __se_sys_recvmmsg net/socket.c:2696 [inline] __x64_sys_recvmmsg+0x89/0xb0 net/socket.c:2696 do_syscall_64+0xcc/0x370 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Reported by Kernel Concurrency Sanitizer on: CPU: 1 PID: 8921 Comm: syz-executor.4 Not tainted 5.4.0-rc3+ #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-26ipv4: fix route update on metric change.Paolo Abeni1-1/+1
Since commit af4d768ad28c ("net/ipv4: Add support for specifying metric of connected routes"), when updating an IP address with a different metric, the associated connected route is updated, too. Still, the mentioned commit doesn't handle properly some corner cases: $ ip addr add dev eth0 192.168.1.0/24 $ ip addr add dev eth0 192.168.2.1/32 peer 192.168.2.2 $ ip addr add dev eth0 192.168.3.1/24 $ ip addr change dev eth0 192.168.1.0/24 metric 10 $ ip addr change dev eth0 192.168.2.1/32 peer 192.168.2.2 metric 10 $ ip addr change dev eth0 192.168.3.1/24 metric 10 $ ip -4 route 192.168.1.0/24 dev eth0 proto kernel scope link src 192.168.1.0 192.168.2.2 dev eth0 proto kernel scope link src 192.168.2.1 192.168.3.0/24 dev eth0 proto kernel scope link src 192.168.2.1 metric 10 Only the last route is correctly updated. The problem is the current test in fib_modify_prefix_metric(): if (!(dev->flags & IFF_UP) || ifa->ifa_flags & (IFA_F_SECONDARY | IFA_F_NOPREFIXROUTE) || ipv4_is_zeronet(prefix) || prefix == ifa->ifa_local || ifa->ifa_prefixlen == 32) Which should be the logical 'not' of the pre-existing test in fib_add_ifaddr(): if (!ipv4_is_zeronet(prefix) && !(ifa->ifa_flags & IFA_F_SECONDARY) && (prefix != addr || ifa->ifa_prefixlen < 32)) To properly negate the original expression, we need to change the last logical 'or' to a logical 'and'. Fixes: af4d768ad28c ("net/ipv4: Add support for specifying metric of connected routes") Reported-and-suggested-by: Beniamino Galvani <bgalvani@redhat.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com> Reviewed-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-21ipv4: fix IPSKB_FRAG_PMTU handling with fragmentationEric Dumazet1-5/+6
This patch removes the iph field from the state structure, which is not properly initialized. Instead, add a new field to make the "do we want to set DF" be the state bit and move the code to set the DF flag from ip_frag_next(). Joint work with Pablo and Linus. Fixes: 19c3401a917b ("net: ipv4: place control buffer handling away from fragmentation iterators") Reported-by: Patrick Schönthaler <patrick@notvads.ovh> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: David S. Miller <davem@davemloft.net>