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2017-06-17NET: Fix /proc/net/arp for AX.25Ralf Baechle
[ Upstream commit 4872e57c812dd312bf8193b5933fa60585cda42f ] When sending ARP requests over AX.25 links the hwaddress in the neighbour cache are not getting initialized. For such an incomplete arp entry ax2asc2 will generate an empty string resulting in /proc/net/arp output like the following: $ cat /proc/net/arp IP address HW type Flags HW address Mask Device 192.168.122.1 0x1 0x2 52:54:00:00:5d:5f * ens3 172.20.1.99 0x3 0x0 * bpq0 The missing field will confuse the procfs parsing of arp(8) resulting in incorrect output for the device such as the following: $ arp Address HWtype HWaddress Flags Mask Iface gateway ether 52:54:00:00:5d:5f C ens3 172.20.1.99 (incomplete) ens3 This changes the content of /proc/net/arp to: $ cat /proc/net/arp IP address HW type Flags HW address Mask Device 172.20.1.99 0x3 0x0 * * bpq0 192.168.122.1 0x1 0x2 52:54:00:00:5d:5f * ens3 To do so it change ax2asc to put the string "*" in buf for a NULL address argument. Finally the HW address field is left aligned in a 17 character field (the length of an ethernet HW address in the usual hex notation) for readability. Signed-off-by: Ralf Baechle <ralf@linux-mips.org> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <alexander.levin@verizon.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-14net: ping: do not abuse udp_poll()Eric Dumazet
[ Upstream commit 77d4b1d36926a9b8387c6b53eeba42bcaaffcea3 ] Alexander reported various KASAN messages triggered in recent kernels The problem is that ping sockets should not use udp_poll() in the first place, and recent changes in UDP stack finally exposed this old bug. Fixes: c319b4d76b9e ("net: ipv4: add IPPROTO_ICMP socket kind") Fixes: 6d0bfe226116 ("net: ipv6: Add IPv6 support to the ping socket.") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Sasha Levin <alexander.levin@verizon.com> Cc: Solar Designer <solar@openwall.com> Cc: Vasiliy Kulikov <segoon@openwall.com> Cc: Lorenzo Colitti <lorenzo@google.com> Acked-By: Lorenzo Colitti <lorenzo@google.com> Tested-By: Lorenzo Colitti <lorenzo@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-14tcp: disallow cwnd undo when switching congestion controlYuchung Cheng
[ Upstream commit 44abafc4cc094214a99f860f778c48ecb23422fc ] When the sender switches its congestion control during loss recovery, if the recovery is spurious then it may incorrectly revert cwnd and ssthresh to the older values set by a previous congestion control. Consider a congestion control (like BBR) that does not use ssthresh and keeps it infinite: the connection may incorrectly revert cwnd to an infinite value when switching from BBR to another congestion control. This patch fixes it by disallowing such cwnd undo operation upon switching congestion control. Note that undo_marker is not reset s.t. the packets that were incorrectly marked lost would be corrected. We only avoid undoing the cwnd in tcp_undo_cwnd_reduction(). Signed-off-by: Yuchung Cheng <ycheng@google.com> Signed-off-by: Soheil Hassas Yeganeh <soheil@google.com> Signed-off-by: Neal Cardwell <ncardwell@google.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>
2017-06-07ipv4: add reference counting to metricsEric Dumazet
[ Upstream commit 3fb07daff8e99243366a081e5129560734de4ada ] Andrey Konovalov reported crashes in ipv4_mtu() I could reproduce the issue with KASAN kernels, between 10.246.7.151 and 10.246.7.152 : 1) 20 concurrent netperf -t TCP_RR -H 10.246.7.152 -l 1000 & 2) At the same time run following loop : while : do ip ro add 10.246.7.152 dev eth0 src 10.246.7.151 mtu 1500 ip ro del 10.246.7.152 dev eth0 src 10.246.7.151 mtu 1500 done Cong Wang attempted to add back rt->fi in commit 82486aa6f1b9 ("ipv4: restore rt->fi for reference counting") but this proved to add some issues that were complex to solve. Instead, I suggested to add a refcount to the metrics themselves, being a standalone object (in particular, no reference to other objects) I tried to make this patch as small as possible to ease its backport, instead of being super clean. Note that we believe that only ipv4 dst need to take care of the metric refcount. But if this is wrong, this patch adds the basic infrastructure to extend this to other families. Many thanks to Julian Anastasov for reviewing this patch, and Cong Wang for his efforts on this problem. Fixes: 2860583fe840 ("ipv4: Kill rt->fi") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Andrey Konovalov <andreyknvl@google.com> Reviewed-by: Julian Anastasov <ja@ssi.bg> Acked-by: Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-07tcp: avoid fastopen API to be used on AF_UNSPECWei Wang
[ Upstream commit ba615f675281d76fd19aa03558777f81fb6b6084 ] Fastopen API should be used to perform fastopen operations on the TCP socket. It does not make sense to use fastopen API to perform disconnect by calling it with AF_UNSPEC. The fastopen data path is also prone to race conditions and bugs when using with AF_UNSPEC. One issue reported and analyzed by Vegard Nossum is as follows: +++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Thread A: Thread B: ------------------------------------------------------------------------ sendto() - tcp_sendmsg() - sk_stream_memory_free() = 0 - goto wait_for_sndbuf - sk_stream_wait_memory() - sk_wait_event() // sleep | sendto(flags=MSG_FASTOPEN, dest_addr=AF_UNSPEC) | - tcp_sendmsg() | - tcp_sendmsg_fastopen() | - __inet_stream_connect() | - tcp_disconnect() //because of AF_UNSPEC | - tcp_transmit_skb()// send RST | - return 0; // no reconnect! | - sk_stream_wait_connect() | - sock_error() | - xchg(&sk->sk_err, 0) | - return -ECONNRESET - ... // wake up, see sk->sk_err == 0 - skb_entail() on TCP_CLOSE socket If the connection is reopened then we will send a brand new SYN packet after thread A has already queued a buffer. At this point I think the socket internal state (sequence numbers etc.) becomes messed up. When the new connection is closed, the FIN-ACK is rejected because the sequence number is outside the window. The other side tries to retransmit, but __tcp_retransmit_skb() calls tcp_trim_head() on an empty skb which corrupts the skb data length and hits a BUG() in copy_and_csum_bits(). +++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Hence, this patch adds a check for AF_UNSPEC in the fastopen data path and return EOPNOTSUPP to user if such case happens. Fixes: cf60af03ca4e7 ("tcp: Fast Open client - sendmsg(MSG_FASTOPEN)") Reported-by: Vegard Nossum <vegard.nossum@oracle.com> Signed-off-by: Wei Wang <weiwan@google.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>
2017-06-07net: Improve handling of failures on link and route dumpsDavid Ahern
[ Upstream commit f6c5775ff0bfa62b072face6bf1d40f659f194b2 ] In general, rtnetlink dumps do not anticipate failure to dump a single object (e.g., link or route) on a single pass. As both route and link objects have grown via more attributes, that is no longer a given. netlink dumps can handle a failure if the dump function returns an error; specifically, netlink_dump adds the return code to the response if it is <= 0 so userspace is notified of the failure. The missing piece is the rtnetlink dump functions returning the error. Fix route and link dump functions to return the errors if no object is added to an skb (detected by skb->len != 0). IPv6 route dumps (rt6_dump_route) already return the error; this patch updates IPv4 and link dumps. Other dump functions may need to be ajusted as well. Reported-by: Jan Moskyto Matejka <mq@ucw.cz> 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>
2017-06-07tcp: eliminate negative reordering in tcp_clean_rtx_queueSoheil Hassas Yeganeh
[ Upstream commit bafbb9c73241760023d8981191ddd30bb1c6dbac ] tcp_ack() can call tcp_fragment() which may dededuct the value tp->fackets_out when MSS changes. When prior_fackets is larger than tp->fackets_out, tcp_clean_rtx_queue() can invoke tcp_update_reordering() with negative values. This results in absurd tp->reodering values higher than sysctl_tcp_max_reordering. Note that tcp_update_reordering indeeds sets tp->reordering to min(sysctl_tcp_max_reordering, metric), but because the comparison is signed, a negative metric always wins. Fixes: c7caf8d3ed7a ("[TCP]: Fix reord detection due to snd_una covered holes") Reported-by: Rebecca Isaacs <risaacs@google.com> Signed-off-by: Soheil Hassas Yeganeh <soheil@google.com> 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> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-07tcp: avoid fragmenting peculiar skbs in SACKYuchung Cheng
[ Upstream commit b451e5d24ba6687c6f0e7319c727a709a1846c06 ] This patch fixes a bug in splitting an SKB during SACK processing. Specifically if an skb contains multiple packets and is only partially sacked in the higher sequences, tcp_match_sack_to_skb() splits the skb and marks the second fragment as SACKed. The current code further attempts rounding up the first fragment to MSS boundaries. But it misses a boundary condition when the rounded-up fragment size (pkt_len) is exactly skb size. Spliting such an skb is pointless and causses a kernel warning and aborts the SACK processing. This patch universally checks such over-split before calling tcp_fragment to prevent these unnecessary warnings. Fixes: adb92db857ee ("tcp: Make SACK code to split only at mss boundaries") Signed-off-by: Yuchung Cheng <ycheng@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Soheil Hassas Yeganeh <soheil@google.com> Acked-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-07dccp/tcp: do not inherit mc_list from parentEric Dumazet
[ Upstream commit 657831ffc38e30092a2d5f03d385d710eb88b09a ] syzkaller found a way to trigger double frees from ip_mc_drop_socket() It turns out that leave a copy of parent mc_list at accept() time, which is very bad. Very similar to commit 8b485ce69876 ("tcp: do not inherit fastopen_req from parent") Initial report from Pray3r, completed by Andrey one. Thanks a lot to them ! Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Pray3r <pray3r.z@gmail.com> Reported-by: Andrey Konovalov <andreyknvl@google.com> Tested-by: Andrey Konovalov <andreyknvl@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-14ipv4, ipv6: ensure raw socket message is big enough to hold an IP headerAlexander Potapenko
[ Upstream commit 86f4c90a1c5c1493f07f2d12c1079f5bf01936f2 ] raw_send_hdrinc() and rawv6_send_hdrinc() expect that the buffer copied from the userspace contains the IPv4/IPv6 header, so if too few bytes are copied, parts of the header may remain uninitialized. This bug has been detected with KMSAN. For the record, the KMSAN report: ================================================================== BUG: KMSAN: use of unitialized memory in nf_ct_frag6_gather+0xf5a/0x44a0 inter: 0 CPU: 0 PID: 1036 Comm: probe Not tainted 4.11.0-rc5+ #2455 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:16 dump_stack+0x143/0x1b0 lib/dump_stack.c:52 kmsan_report+0x16b/0x1e0 mm/kmsan/kmsan.c:1078 __kmsan_warning_32+0x5c/0xa0 mm/kmsan/kmsan_instr.c:510 nf_ct_frag6_gather+0xf5a/0x44a0 net/ipv6/netfilter/nf_conntrack_reasm.c:577 ipv6_defrag+0x1d9/0x280 net/ipv6/netfilter/nf_defrag_ipv6_hooks.c:68 nf_hook_entry_hookfn ./include/linux/netfilter.h:102 nf_hook_slow+0x13f/0x3c0 net/netfilter/core.c:310 nf_hook ./include/linux/netfilter.h:212 NF_HOOK ./include/linux/netfilter.h:255 rawv6_send_hdrinc net/ipv6/raw.c:673 rawv6_sendmsg+0x2fcb/0x41a0 net/ipv6/raw.c:919 inet_sendmsg+0x3f8/0x6d0 net/ipv4/af_inet.c:762 sock_sendmsg_nosec net/socket.c:633 sock_sendmsg net/socket.c:643 SYSC_sendto+0x6a5/0x7c0 net/socket.c:1696 SyS_sendto+0xbc/0xe0 net/socket.c:1664 do_syscall_64+0x72/0xa0 arch/x86/entry/common.c:285 entry_SYSCALL64_slow_path+0x25/0x25 arch/x86/entry/entry_64.S:246 RIP: 0033:0x436e03 RSP: 002b:00007ffce48baf38 EFLAGS: 00000246 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 00000000004002b0 RCX: 0000000000436e03 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000003 RBP: 00007ffce48baf90 R08: 00007ffce48baf50 R09: 000000000000001c R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000401790 R14: 0000000000401820 R15: 0000000000000000 origin: 00000000d9400053 save_stack_trace+0x16/0x20 arch/x86/kernel/stacktrace.c:59 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:362 kmsan_internal_poison_shadow+0xb1/0x1a0 mm/kmsan/kmsan.c:257 kmsan_poison_shadow+0x6d/0xc0 mm/kmsan/kmsan.c:270 slab_alloc_node mm/slub.c:2735 __kmalloc_node_track_caller+0x1f4/0x390 mm/slub.c:4341 __kmalloc_reserve net/core/skbuff.c:138 __alloc_skb+0x2cd/0x740 net/core/skbuff.c:231 alloc_skb ./include/linux/skbuff.h:933 alloc_skb_with_frags+0x209/0xbc0 net/core/skbuff.c:4678 sock_alloc_send_pskb+0x9ff/0xe00 net/core/sock.c:1903 sock_alloc_send_skb+0xe4/0x100 net/core/sock.c:1920 rawv6_send_hdrinc net/ipv6/raw.c:638 rawv6_sendmsg+0x2918/0x41a0 net/ipv6/raw.c:919 inet_sendmsg+0x3f8/0x6d0 net/ipv4/af_inet.c:762 sock_sendmsg_nosec net/socket.c:633 sock_sendmsg net/socket.c:643 SYSC_sendto+0x6a5/0x7c0 net/socket.c:1696 SyS_sendto+0xbc/0xe0 net/socket.c:1664 do_syscall_64+0x72/0xa0 arch/x86/entry/common.c:285 return_from_SYSCALL_64+0x0/0x6a arch/x86/entry/entry_64.S:246 ================================================================== , triggered by the following syscalls: socket(PF_INET6, SOCK_RAW, IPPROTO_RAW) = 3 sendto(3, NULL, 0, 0, {sa_family=AF_INET6, sin6_port=htons(0), inet_pton(AF_INET6, "ff00::", &sin6_addr), sin6_flowinfo=0, sin6_scope_id=0}, 28) = -1 EPERM A similar report is triggered in net/ipv4/raw.c if we use a PF_INET socket instead of a PF_INET6 one. Signed-off-by: Alexander Potapenko <glider@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-14tcp: do not inherit fastopen_req from parentEric Dumazet
[ Upstream commit 8b485ce69876c65db12ed390e7f9c0d2a64eff2c ] Under fuzzer stress, it is possible that a child gets a non NULL fastopen_req pointer from its parent at accept() time, when/if parent morphs from listener to active session. We need to make sure this can not happen, by clearing the field after socket cloning. BUG: Double free or freeing an invalid pointer Unexpected shadow byte: 0xFB CPU: 3 PID: 20933 Comm: syz-executor3 Not tainted 4.11.0+ #306 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011 Call Trace: <IRQ> __dump_stack lib/dump_stack.c:16 [inline] dump_stack+0x292/0x395 lib/dump_stack.c:52 kasan_object_err+0x1c/0x70 mm/kasan/report.c:164 kasan_report_double_free+0x5c/0x70 mm/kasan/report.c:185 kasan_slab_free+0x9d/0xc0 mm/kasan/kasan.c:580 slab_free_hook mm/slub.c:1357 [inline] slab_free_freelist_hook mm/slub.c:1379 [inline] slab_free mm/slub.c:2961 [inline] kfree+0xe8/0x2b0 mm/slub.c:3882 tcp_free_fastopen_req net/ipv4/tcp.c:1077 [inline] tcp_disconnect+0xc15/0x13e0 net/ipv4/tcp.c:2328 inet_child_forget+0xb8/0x600 net/ipv4/inet_connection_sock.c:898 inet_csk_reqsk_queue_add+0x1e7/0x250 net/ipv4/inet_connection_sock.c:928 tcp_get_cookie_sock+0x21a/0x510 net/ipv4/syncookies.c:217 cookie_v4_check+0x1a19/0x28b0 net/ipv4/syncookies.c:384 tcp_v4_cookie_check net/ipv4/tcp_ipv4.c:1384 [inline] tcp_v4_do_rcv+0x731/0x940 net/ipv4/tcp_ipv4.c:1421 tcp_v4_rcv+0x2dc0/0x31c0 net/ipv4/tcp_ipv4.c:1715 ip_local_deliver_finish+0x4cc/0xc20 net/ipv4/ip_input.c:216 NF_HOOK include/linux/netfilter.h:257 [inline] ip_local_deliver+0x1ce/0x700 net/ipv4/ip_input.c:257 dst_input include/net/dst.h:492 [inline] ip_rcv_finish+0xb1d/0x20b0 net/ipv4/ip_input.c:396 NF_HOOK include/linux/netfilter.h:257 [inline] ip_rcv+0xd8c/0x19c0 net/ipv4/ip_input.c:487 __netif_receive_skb_core+0x1ad1/0x3400 net/core/dev.c:4210 __netif_receive_skb+0x2a/0x1a0 net/core/dev.c:4248 process_backlog+0xe5/0x6c0 net/core/dev.c:4868 napi_poll net/core/dev.c:5270 [inline] net_rx_action+0xe70/0x18e0 net/core/dev.c:5335 __do_softirq+0x2fb/0xb99 kernel/softirq.c:284 do_softirq_own_stack+0x1c/0x30 arch/x86/entry/entry_64.S:899 </IRQ> do_softirq.part.17+0x1e8/0x230 kernel/softirq.c:328 do_softirq kernel/softirq.c:176 [inline] __local_bh_enable_ip+0x1cf/0x1e0 kernel/softirq.c:181 local_bh_enable include/linux/bottom_half.h:31 [inline] rcu_read_unlock_bh include/linux/rcupdate.h:931 [inline] ip_finish_output2+0x9ab/0x15e0 net/ipv4/ip_output.c:230 ip_finish_output+0xa35/0xdf0 net/ipv4/ip_output.c:316 NF_HOOK_COND include/linux/netfilter.h:246 [inline] ip_output+0x1f6/0x7b0 net/ipv4/ip_output.c:404 dst_output include/net/dst.h:486 [inline] ip_local_out+0x95/0x160 net/ipv4/ip_output.c:124 ip_queue_xmit+0x9a8/0x1a10 net/ipv4/ip_output.c:503 tcp_transmit_skb+0x1ade/0x3470 net/ipv4/tcp_output.c:1057 tcp_write_xmit+0x79e/0x55b0 net/ipv4/tcp_output.c:2265 __tcp_push_pending_frames+0xfa/0x3a0 net/ipv4/tcp_output.c:2450 tcp_push+0x4ee/0x780 net/ipv4/tcp.c:683 tcp_sendmsg+0x128d/0x39b0 net/ipv4/tcp.c:1342 inet_sendmsg+0x164/0x5b0 net/ipv4/af_inet.c:762 sock_sendmsg_nosec net/socket.c:633 [inline] sock_sendmsg+0xca/0x110 net/socket.c:643 SYSC_sendto+0x660/0x810 net/socket.c:1696 SyS_sendto+0x40/0x50 net/socket.c:1664 entry_SYSCALL_64_fastpath+0x1f/0xbe RIP: 0033:0x446059 RSP: 002b:00007faa6761fb58 EFLAGS: 00000282 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 0000000000000017 RCX: 0000000000446059 RDX: 0000000000000001 RSI: 0000000020ba3fcd RDI: 0000000000000017 RBP: 00000000006e40a0 R08: 0000000020ba4ff0 R09: 0000000000000010 R10: 0000000020000000 R11: 0000000000000282 R12: 0000000000708150 R13: 0000000000000000 R14: 00007faa676209c0 R15: 00007faa67620700 Object at ffff88003b5bbcb8, in cache kmalloc-64 size: 64 Allocated: PID = 20909 save_stack_trace+0x16/0x20 arch/x86/kernel/stacktrace.c:59 save_stack+0x43/0xd0 mm/kasan/kasan.c:513 set_track mm/kasan/kasan.c:525 [inline] kasan_kmalloc+0xad/0xe0 mm/kasan/kasan.c:616 kmem_cache_alloc_trace+0x82/0x270 mm/slub.c:2745 kmalloc include/linux/slab.h:490 [inline] kzalloc include/linux/slab.h:663 [inline] tcp_sendmsg_fastopen net/ipv4/tcp.c:1094 [inline] tcp_sendmsg+0x221a/0x39b0 net/ipv4/tcp.c:1139 inet_sendmsg+0x164/0x5b0 net/ipv4/af_inet.c:762 sock_sendmsg_nosec net/socket.c:633 [inline] sock_sendmsg+0xca/0x110 net/socket.c:643 SYSC_sendto+0x660/0x810 net/socket.c:1696 SyS_sendto+0x40/0x50 net/socket.c:1664 entry_SYSCALL_64_fastpath+0x1f/0xbe Freed: PID = 20909 save_stack_trace+0x16/0x20 arch/x86/kernel/stacktrace.c:59 save_stack+0x43/0xd0 mm/kasan/kasan.c:513 set_track mm/kasan/kasan.c:525 [inline] kasan_slab_free+0x73/0xc0 mm/kasan/kasan.c:589 slab_free_hook mm/slub.c:1357 [inline] slab_free_freelist_hook mm/slub.c:1379 [inline] slab_free mm/slub.c:2961 [inline] kfree+0xe8/0x2b0 mm/slub.c:3882 tcp_free_fastopen_req net/ipv4/tcp.c:1077 [inline] tcp_disconnect+0xc15/0x13e0 net/ipv4/tcp.c:2328 __inet_stream_connect+0x20c/0xf90 net/ipv4/af_inet.c:593 tcp_sendmsg_fastopen net/ipv4/tcp.c:1111 [inline] tcp_sendmsg+0x23a8/0x39b0 net/ipv4/tcp.c:1139 inet_sendmsg+0x164/0x5b0 net/ipv4/af_inet.c:762 sock_sendmsg_nosec net/socket.c:633 [inline] sock_sendmsg+0xca/0x110 net/socket.c:643 SYSC_sendto+0x660/0x810 net/socket.c:1696 SyS_sendto+0x40/0x50 net/socket.c:1664 entry_SYSCALL_64_fastpath+0x1f/0xbe Fixes: e994b2f0fb92 ("tcp: do not lock listener to process SYN packets") Fixes: 7db92362d2fe ("tcp: fix potential double free issue for fastopen_req") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Andrey Konovalov <andreyknvl@google.com> Acked-by: Wei Wang <weiwan@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-14tcp: fix wraparound issue in tcp_lpEric Dumazet
[ Upstream commit a9f11f963a546fea9144f6a6d1a307e814a387e7 ] Be careful when comparing tcp_time_stamp to some u32 quantity, otherwise result can be surprising. Fixes: 7c106d7e782b ("[TCP]: TCP Low Priority congestion control") 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>
2017-05-14tcp: do not underestimate skb->truesize in tcp_trim_head()Eric Dumazet
[ Upstream commit 7162fb242cb8322beb558828fd26b33c3e9fc805 ] Andrey found a way to trigger the WARN_ON_ONCE(delta < len) in skb_try_coalesce() using syzkaller and a filter attached to a TCP socket over loopback interface. I believe one issue with looped skbs is that tcp_trim_head() can end up producing skb with under estimated truesize. It hardly matters for normal conditions, since packets sent over loopback are never truncated. Bytes trimmed from skb->head should not change skb truesize, since skb->head is not reallocated. Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Andrey Konovalov <andreyknvl@google.com> Tested-by: Andrey Konovalov <andreyknvl@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-02tcp: clear saved_syn in tcp_disconnect()Eric Dumazet
[ Upstream commit 17c3060b1701fc69daedb4c90be6325d3d9fca8e ] In the (very unlikely) case a passive socket becomes a listener, we do not want to duplicate its saved SYN headers. This would lead to double frees, use after free, and please hackers and various fuzzers Tested: 0 socket(..., SOCK_STREAM, IPPROTO_TCP) = 3 +0 setsockopt(3, IPPROTO_TCP, TCP_SAVE_SYN, [1], 4) = 0 +0 fcntl(3, F_SETFL, O_RDWR|O_NONBLOCK) = 0 +0 bind(3, ..., ...) = 0 +0 listen(3, 5) = 0 +0 < S 0:0(0) win 32972 <mss 1460,nop,wscale 7> +0 > S. 0:0(0) ack 1 <...> +.1 < . 1:1(0) ack 1 win 257 +0 accept(3, ..., ...) = 4 +0 connect(4, AF_UNSPEC, ...) = 0 +0 close(3) = 0 +0 bind(4, ..., ...) = 0 +0 listen(4, 5) = 0 +0 < S 0:0(0) win 32972 <mss 1460,nop,wscale 7> +0 > S. 0:0(0) ack 1 <...> +.1 < . 1:1(0) ack 1 win 257 Fixes: cd8ae85299d5 ("tcp: provide SYN headers for passive connections") 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>
2017-05-02net: ipv4: fix multipath RTM_GETROUTE behavior when iif is givenFlorian Larysch
[ Upstream commit a8801799c6975601fd58ae62f48964caec2eb83f ] inet_rtm_getroute synthesizes a skeletal ICMP skb, which is passed to ip_route_input when iif is given. If a multipath route is present for the designated destination, ip_multipath_icmp_hash ends up being called, which uses the source/destination addresses within the skb to calculate a hash. However, those are not set in the synthetic skb, causing it to return an arbitrary and incorrect result. Instead, use UDP, which gets no such special treatment. Signed-off-by: Florian Larysch <fl@n621.de> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-04-30ping: implement proper lockingEric Dumazet
commit 43a6684519ab0a6c52024b5e25322476cabad893 upstream. We got a report of yet another bug in ping http://www.openwall.com/lists/oss-security/2017/03/24/6 ->disconnect() is not called with socket lock held. Fix this by acquiring ping rwlock earlier. Thanks to Daniel, Alexander and Andrey for letting us know this problem. Fixes: c319b4d76b9e ("net: ipv4: add IPPROTO_ICMP socket kind") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Daniel Jiang <danieljiang0415@gmail.com> Reported-by: Solar Designer <solar@openwall.com> Reported-by: Andrey Konovalov <andreyknvl@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Cc: Ben Hutchings <ben.hutchings@codethink.co.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-03-30tcp: initialize icsk_ack.lrcvtime at session start timeEric Dumazet
[ Upstream commit 15bb7745e94a665caf42bfaabf0ce062845b533b ] icsk_ack.lrcvtime has a 0 value at socket creation time. tcpi_last_data_recv can have bogus value if no payload is ever received. This patch initializes icsk_ack.lrcvtime for active sessions in tcp_finish_connect(), and for passive sessions in tcp_create_openreq_child() Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-03-30ipv4: provide stronger user input validation in nl_fib_input()Eric Dumazet
[ Upstream commit c64c0b3cac4c5b8cb093727d2c19743ea3965c0b ] Alexander reported a KMSAN splat caused by reads of uninitialized field (tb_id_in) from user provided struct fib_result_nl It turns out nl_fib_input() sanity tests on user input is a bit wrong : User can pretend nlh->nlmsg_len is big enough, but provide at sendmsg() time a too small buffer. Reported-by: Alexander Potapenko <glider@google.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>
2017-03-22dccp/tcp: fix routing redirect raceJon Maxwell
[ Upstream commit 45caeaa5ac0b4b11784ac6f932c0ad4c6b67cda0 ] As Eric Dumazet pointed out this also needs to be fixed in IPv6. v2: Contains the IPv6 tcp/Ipv6 dccp patches as well. We have seen a few incidents lately where a dst_enty has been freed with a dangling TCP socket reference (sk->sk_dst_cache) pointing to that dst_entry. If the conditions/timings are right a crash then ensues when the freed dst_entry is referenced later on. A Common crashing back trace is: #8 [] page_fault at ffffffff8163e648 [exception RIP: __tcp_ack_snd_check+74] . . #9 [] tcp_rcv_established at ffffffff81580b64 #10 [] tcp_v4_do_rcv at ffffffff8158b54a #11 [] tcp_v4_rcv at ffffffff8158cd02 #12 [] ip_local_deliver_finish at ffffffff815668f4 #13 [] ip_local_deliver at ffffffff81566bd9 #14 [] ip_rcv_finish at ffffffff8156656d #15 [] ip_rcv at ffffffff81566f06 #16 [] __netif_receive_skb_core at ffffffff8152b3a2 #17 [] __netif_receive_skb at ffffffff8152b608 #18 [] netif_receive_skb at ffffffff8152b690 #19 [] vmxnet3_rq_rx_complete at ffffffffa015eeaf [vmxnet3] #20 [] vmxnet3_poll_rx_only at ffffffffa015f32a [vmxnet3] #21 [] net_rx_action at ffffffff8152bac2 #22 [] __do_softirq at ffffffff81084b4f #23 [] call_softirq at ffffffff8164845c #24 [] do_softirq at ffffffff81016fc5 #25 [] irq_exit at ffffffff81084ee5 #26 [] do_IRQ at ffffffff81648ff8 Of course it may happen with other NIC drivers as well. It's found the freed dst_entry here: 224 static bool tcp_in_quickack_mode(struct sock *sk)↩ 225 {↩ 226 ▹ const struct inet_connection_sock *icsk = inet_csk(sk);↩ 227 ▹ const struct dst_entry *dst = __sk_dst_get(sk);↩ 228 ↩ 229 ▹ return (dst && dst_metric(dst, RTAX_QUICKACK)) ||↩ 230 ▹ ▹ (icsk->icsk_ack.quick && !icsk->icsk_ack.pingpong);↩ 231 }↩ But there are other backtraces attributed to the same freed dst_entry in netfilter code as well. All the vmcores showed 2 significant clues: - Remote hosts behind the default gateway had always been redirected to a different gateway. A rtable/dst_entry will be added for that host. Making more dst_entrys with lower reference counts. Making this more probable. - All vmcores showed a postitive LockDroppedIcmps value, e.g: LockDroppedIcmps 267 A closer look at the tcp_v4_err() handler revealed that do_redirect() will run regardless of whether user space has the socket locked. This can result in a race condition where the same dst_entry cached in sk->sk_dst_entry can be decremented twice for the same socket via: do_redirect()->__sk_dst_check()-> dst_release(). Which leads to the dst_entry being prematurely freed with another socket pointing to it via sk->sk_dst_cache and a subsequent crash. To fix this skip do_redirect() if usespace has the socket locked. Instead let the redirect take place later when user space does not have the socket locked. The dccp/IPv6 code is very similar in this respect, so fixing it there too. As Eric Garver pointed out the following commit now invalidates routes. Which can set the dst->obsolete flag so that ipv4_dst_check() returns null and triggers the dst_release(). Fixes: ceb3320610d6 ("ipv4: Kill routes during PMTU/redirect updates.") Cc: Eric Garver <egarver@redhat.com> Cc: Hannes Sowa <hsowa@redhat.com> Signed-off-by: Jon Maxwell <jmaxwell37@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-03-22tcp: fix various issues for sockets morphing to listen stateEric Dumazet
[ Upstream commit 02b2faaf0af1d85585f6d6980e286d53612acfc2 ] Dmitry Vyukov reported a divide by 0 triggered by syzkaller, exploiting tcp_disconnect() path that was never really considered and/or used before syzkaller ;) I was not able to reproduce the bug, but it seems issues here are the three possible actions that assumed they would never trigger on a listener. 1) tcp_write_timer_handler 2) tcp_delack_timer_handler 3) MTU reduction Only IPv6 MTU reduction was properly testing TCP_CLOSE and TCP_LISTEN states from tcp_v6_mtu_reduced() Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Dmitry Vyukov <dvyukov@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-03-22ipv4: mask tos for input routeJulian Anastasov
[ Upstream commit 6e28099d38c0e50d62c1afc054e37e573adf3d21 ] Restore the lost masking of TOS in input route code to allow ip rules to match it properly. Problem [1] noticed by Shmulik Ladkani <shmulik.ladkani@gmail.com> [1] http://marc.info/?t=137331755300040&r=1&w=2 Fixes: 89aef8921bfb ("ipv4: Delete routing cache.") Signed-off-by: Julian Anastasov <ja@ssi.bg> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-02-26ip: fix IP_CHECKSUM handlingPaolo Abeni
[ Upstream commit ca4ef4574f1ee5252e2cd365f8f5d5bafd048f32 ] The skbs processed by ip_cmsg_recv() are not guaranteed to be linear e.g. when sending UDP packets over loopback with MSGMORE. Using csum_partial() on [potentially] the whole skb len is dangerous; instead be on the safe side and use skb_checksum(). Thanks to syzkaller team to detect the issue and provide the reproducer. v1 -> v2: - move the variable declaration in a tighter scope Fixes: ad6f939ab193 ("ip: Add offset parameter to ip_cmsg_recv") Reported-by: Andrey Konovalov <andreyknvl@google.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-02-18ping: fix a null pointer dereferenceWANG Cong
[ Upstream commit 73d2c6678e6c3af7e7a42b1e78cd0211782ade32 ] Andrey reported a kernel crash: general protection fault: 0000 [#1] SMP KASAN Dumping ftrace buffer: (ftrace buffer empty) Modules linked in: CPU: 2 PID: 3880 Comm: syz-executor1 Not tainted 4.10.0-rc6+ #124 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011 task: ffff880060048040 task.stack: ffff880069be8000 RIP: 0010:ping_v4_push_pending_frames net/ipv4/ping.c:647 [inline] RIP: 0010:ping_v4_sendmsg+0x1acd/0x23f0 net/ipv4/ping.c:837 RSP: 0018:ffff880069bef8b8 EFLAGS: 00010206 RAX: dffffc0000000000 RBX: ffff880069befb90 RCX: 0000000000000000 RDX: 0000000000000018 RSI: ffff880069befa30 RDI: 00000000000000c2 RBP: ffff880069befbb8 R08: 0000000000000008 R09: 0000000000000000 R10: 0000000000000002 R11: 0000000000000000 R12: ffff880069befab0 R13: ffff88006c624a80 R14: ffff880069befa70 R15: 0000000000000000 FS: 00007f6f7c716700(0000) GS:ffff88006de00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00000000004a6f28 CR3: 000000003a134000 CR4: 00000000000006e0 Call Trace: inet_sendmsg+0x164/0x5b0 net/ipv4/af_inet.c:744 sock_sendmsg_nosec net/socket.c:635 [inline] sock_sendmsg+0xca/0x110 net/socket.c:645 SYSC_sendto+0x660/0x810 net/socket.c:1687 SyS_sendto+0x40/0x50 net/socket.c:1655 entry_SYSCALL_64_fastpath+0x1f/0xc2 This is because we miss a check for NULL pointer for skb_peek() when the queue is empty. Other places already have the same check. Fixes: c319b4d76b9e ("net: ipv4: add IPPROTO_ICMP socket kind") Reported-by: Andrey Konovalov <andreyknvl@google.com> Tested-by: Andrey Konovalov <andreyknvl@google.com> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-02-18tcp: avoid infinite loop in tcp_splice_read()Eric Dumazet
[ Upstream commit ccf7abb93af09ad0868ae9033d1ca8108bdaec82 ] Splicing from TCP socket is vulnerable when a packet with URG flag is received and stored into receive queue. __tcp_splice_read() returns 0, and sk_wait_data() immediately returns since there is the problematic skb in queue. This is a nice way to burn cpu (aka infinite loop) and trigger soft lockups. Again, this gem was found by syzkaller tool. Fixes: 9c55e01c0cc8 ("[TCP]: Splice receive support.") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Dmitry Vyukov <dvyukov@google.com> Cc: Willy Tarreau <w@1wt.eu> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-02-18netlabel: out of bound access in cipso_v4_validate()Eric Dumazet
[ Upstream commit d71b7896886345c53ef1d84bda2bc758554f5d61 ] syzkaller found another out of bound access in ip_options_compile(), or more exactly in cipso_v4_validate() Fixes: 20e2a8648596 ("cipso: handle CIPSO options correctly when NetLabel is disabled") Fixes: 446fda4f2682 ("[NetLabel]: CIPSOv4 engine") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Dmitry Vyukov <dvyukov@google.com> Cc: Paul Moore <paul@paul-moore.com> Acked-by: Paul Moore <paul@paul-moore.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-02-18ipv4: keep skb->dst around in presence of IP optionsEric Dumazet
[ Upstream commit 34b2cef20f19c87999fff3da4071e66937db9644 ] Andrey Konovalov got crashes in __ip_options_echo() when a NULL skb->dst is accessed. ipv4_pktinfo_prepare() should not drop the dst if (evil) IP options are present. We could refine the test to the presence of ts_needtime or srr, but IP options are not often used, so let's be conservative. Thanks to syzkaller team for finding this bug. Fixes: d826eb14ecef ("ipv4: PKTINFO doesnt need dst reference") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Andrey Konovalov <andreyknvl@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-02-18tcp: fix 0 divide in __tcp_select_window()Eric Dumazet
[ Upstream commit 06425c308b92eaf60767bc71d359f4cbc7a561f8 ] syszkaller fuzzer was able to trigger a divide by zero, when TCP window scaling is not enabled. SO_RCVBUF can be used not only to increase sk_rcvbuf, also to decrease it below current receive buffers utilization. If mss is negative or 0, just return a zero TCP window. Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Dmitry Vyukov <dvyukov@google.com> Acked-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-02-04tcp: initialize max window for a new fastopen socketAlexey Kodanev
[ Upstream commit 0dbd7ff3ac5017a46033a9d0a87a8267d69119d9 ] Found that if we run LTP netstress test with large MSS (65K), the first attempt from server to send data comparable to this MSS on fastopen connection will be delayed by the probe timer. Here is an example: < S seq 0:0 win 43690 options [mss 65495 wscale 7 tfo cookie] length 32 > S. seq 0:0 ack 1 win 43690 options [mss 65495 wscale 7] length 0 < . ack 1 win 342 length 0 Inside tcp_sendmsg(), tcp_send_mss() returns max MSS in 'mss_now', as well as in 'size_goal'. This results the segment not queued for transmition until all the data copied from user buffer. Then, inside __tcp_push_pending_frames(), it breaks on send window test and continues with the check probe timer. Fragmentation occurs in tcp_write_wakeup()... +0.2 > P. seq 1:43777 ack 1 win 342 length 43776 < . ack 43777, win 1365 length 0 > P. seq 43777:65001 ack 1 win 342 options [...] length 21224 ... This also contradicts with the fact that we should bound to the half of the window if it is large. Fix this flaw by correctly initializing max_window. Before that, it could have large values that affect further calculations of 'size_goal'. Fixes: 168a8f58059a ("tcp: TCP Fast Open Server - main code path") Signed-off-by: Alexey Kodanev <alexey.kodanev@oracle.com> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-02-04tcp: fix tcp_fastopen unaligned access complaints on sparcShannon Nelson
[ Upstream commit 003c941057eaa868ca6fedd29a274c863167230d ] Fix up a data alignment issue on sparc by swapping the order of the cookie byte array field with the length field in struct tcp_fastopen_cookie, and making it a proper union to clean up the typecasting. This addresses log complaints like these: log_unaligned: 113 callbacks suppressed Kernel unaligned access at TPC[976490] tcp_try_fastopen+0x2d0/0x360 Kernel unaligned access at TPC[9764ac] tcp_try_fastopen+0x2ec/0x360 Kernel unaligned access at TPC[9764c8] tcp_try_fastopen+0x308/0x360 Kernel unaligned access at TPC[9764e4] tcp_try_fastopen+0x324/0x360 Kernel unaligned access at TPC[976490] tcp_try_fastopen+0x2d0/0x360 Cc: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: Shannon Nelson <shannon.nelson@oracle.com> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-02-04net: ipv4: fix table id in getroute responseDavid Ahern
[ Upstream commit 8a430ed50bb1b19ca14a46661f3b1b35f2fb5c39 ] rtm_table is an 8-bit field while table ids are allowed up to u32. Commit 709772e6e065 ("net: Fix routing tables with id > 255 for legacy software") added the preference to set rtm_table in dumps to RT_TABLE_COMPAT if the table id is > 255. The table id returned on get route requests should do the same. Fixes: c36ba6603a11 ("net: Allow user to get table id from route lookup") Signed-off-by: David Ahern <dsa@cumulusnetworks.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-02-04net: lwtunnel: Handle lwtunnel_fill_encap failureDavid Ahern
[ Upstream commit ea7a80858f57d8878b1499ea0f1b8a635cc48de7 ] Handle failure in lwtunnel_fill_encap adding attributes to skb. Fixes: 571e722676fe ("ipv4: support for fib route lwtunnel encap attributes") Fixes: 19e42e451506 ("ipv6: support for fib route lwtunnel encap attributes") Signed-off-by: David Ahern <dsa@cumulusnetworks.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-15net: ipv4: Fix multipath selection with vrfDavid Ahern
[ Upstream commit 7a18c5b9fb31a999afc62b0e60978aa896fc89e9 ] fib_select_path does not call fib_select_multipath if oif is set in the flow struct. For VRF use cases oif is always set, so multipath route selection is bypassed. Use the FLOWI_FLAG_SKIP_NH_OIF to skip the oif check similar to what is done in fib_table_lookup. Add saddr and proto to the flow struct for the fib lookup done by the VRF driver to better match hash computation for a flow. Fixes: 613d09b30f8b ("net: Use VRF device index for lookups on TX") Signed-off-by: David Ahern <dsa@cumulusnetworks.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-15ipv4: Do not allow MAIN to be alias for new LOCAL w/ custom rulesAlexander Duyck
[ Upstream commit 5350d54f6cd12eaff623e890744c79b700bd3f17 ] In the case of custom rules being present we need to handle the case of the LOCAL table being intialized after the new rule has been added. To address that I am adding a new check so that we can make certain we don't use an alias of MAIN for LOCAL when allocating a new table. Fixes: 0ddcf43d5d4a ("ipv4: FIB Local/MAIN table collapse") Reported-by: Oliver Brunel <jjk@jjacky.com> Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-15igmp: Make igmp group member RFC 3376 compliantMichal Tesar
[ Upstream commit 7ababb782690e03b78657e27bd051e20163af2d6 ] 5.2. Action on Reception of a Query When a system receives a Query, it does not respond immediately. Instead, it delays its response by a random amount of time, bounded by the Max Resp Time value derived from the Max Resp Code in the received Query message. A system may receive a variety of Queries on different interfaces and of different kinds (e.g., General Queries, Group-Specific Queries, and Group-and-Source-Specific Queries), each of which may require its own delayed response. Before scheduling a response to a Query, the system must first consider previously scheduled pending responses and in many cases schedule a combined response. Therefore, the system must be able to maintain the following state: o A timer per interface for scheduling responses to General Queries. o A per-group and interface timer for scheduling responses to Group- Specific and Group-and-Source-Specific Queries. o A per-group and interface list of sources to be reported in the response to a Group-and-Source-Specific Query. When a new Query with the Router-Alert option arrives on an interface, provided the system has state to report, a delay for a response is randomly selected in the range (0, [Max Resp Time]) where Max Resp Time is derived from Max Resp Code in the received Query message. The following rules are then used to determine if a Report needs to be scheduled and the type of Report to schedule. The rules are considered in order and only the first matching rule is applied. 1. If there is a pending response to a previous General Query scheduled sooner than the selected delay, no additional response needs to be scheduled. 2. If the received Query is a General Query, the interface timer is used to schedule a response to the General Query after the selected delay. Any previously pending response to a General Query is canceled. --8<-- Currently the timer is rearmed with new random expiration time for every incoming query regardless of possibly already pending report. Which is not aligned with the above RFE. It also might happen that higher rate of incoming queries can postpone the report after the expiration time of the first query causing group membership loss. Now the per interface general query timer is rearmed only when there is no pending report already scheduled on that interface or the newly selected expiration time is before the already pending scheduled report. Signed-off-by: Michal Tesar <mtesar@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-12-10esp4: Fix integrity verification when ESN are usedTobias Brunner
commit 7c7fedd51c02f4418e8b2eed64bdab601f882aa4 upstream. When handling inbound packets, the two halves of the sequence number stored on the skb are already in network order. Fixes: 7021b2e1cddd ("esp4: Switch to new AEAD interface") Signed-off-by: Tobias Brunner <tobias@strongswan.org> Acked-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-12-10ipv4: Set skb->protocol properly for local outputEli Cooper
commit f4180439109aa720774baafdd798b3234ab1a0d2 upstream. When xfrm is applied to TSO/GSO packets, it follows this path: xfrm_output() -> xfrm_output_gso() -> skb_gso_segment() where skb_gso_segment() relies on skb->protocol to function properly. This patch sets skb->protocol to ETH_P_IP before dst_output() is called, fixing a bug where GSO packets sent through a sit tunnel are dropped when xfrm is involved. Signed-off-by: Eli Cooper <elicooper@gmx.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-12-10net: ping: check minimum size on ICMP header lengthKees Cook
[ Upstream commit 0eab121ef8750a5c8637d51534d5e9143fb0633f ] Prior to commit c0371da6047a ("put iov_iter into msghdr") in v3.19, there was no check that the iovec contained enough bytes for an ICMP header, and the read loop would walk across neighboring stack contents. Since the iov_iter conversion, bad arguments are noticed, but the returned error is EFAULT. Returning EINVAL is a clearer error and also solves the problem prior to v3.19. This was found using trinity with KASAN on v3.18: BUG: KASAN: stack-out-of-bounds in memcpy_fromiovec+0x60/0x114 at addr ffffffc071077da0 Read of size 8 by task trinity-c2/9623 page:ffffffbe034b9a08 count:0 mapcount:0 mapping: (null) index:0x0 flags: 0x0() page dumped because: kasan: bad access detected CPU: 0 PID: 9623 Comm: trinity-c2 Tainted: G BU 3.18.0-dirty #15 Hardware name: Google Tegra210 Smaug Rev 1,3+ (DT) Call trace: [<ffffffc000209c98>] dump_backtrace+0x0/0x1ac arch/arm64/kernel/traps.c:90 [<ffffffc000209e54>] show_stack+0x10/0x1c arch/arm64/kernel/traps.c:171 [< inline >] __dump_stack lib/dump_stack.c:15 [<ffffffc000f18dc4>] dump_stack+0x7c/0xd0 lib/dump_stack.c:50 [< inline >] print_address_description mm/kasan/report.c:147 [< inline >] kasan_report_error mm/kasan/report.c:236 [<ffffffc000373dcc>] kasan_report+0x380/0x4b8 mm/kasan/report.c:259 [< inline >] check_memory_region mm/kasan/kasan.c:264 [<ffffffc00037352c>] __asan_load8+0x20/0x70 mm/kasan/kasan.c:507 [<ffffffc0005b9624>] memcpy_fromiovec+0x5c/0x114 lib/iovec.c:15 [< inline >] memcpy_from_msg include/linux/skbuff.h:2667 [<ffffffc000ddeba0>] ping_common_sendmsg+0x50/0x108 net/ipv4/ping.c:674 [<ffffffc000dded30>] ping_v4_sendmsg+0xd8/0x698 net/ipv4/ping.c:714 [<ffffffc000dc91dc>] inet_sendmsg+0xe0/0x12c net/ipv4/af_inet.c:749 [< inline >] __sock_sendmsg_nosec net/socket.c:624 [< inline >] __sock_sendmsg net/socket.c:632 [<ffffffc000cab61c>] sock_sendmsg+0x124/0x164 net/socket.c:643 [< inline >] SYSC_sendto net/socket.c:1797 [<ffffffc000cad270>] SyS_sendto+0x178/0x1d8 net/socket.c:1761 CVE-2016-8399 Reported-by: Qidan He <i@flanker017.me> Fixes: c319b4d76b9e ("net: ipv4: add IPPROTO_ICMP socket kind") Cc: stable@vger.kernel.org Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-11-21tcp: take care of truncations done by sk_filter()Eric Dumazet
[ Upstream commit ac6e780070e30e4c35bd395acfe9191e6268bdd3 ] With syzkaller help, Marco Grassi found a bug in TCP stack, crashing in tcp_collapse() Root cause is that sk_filter() can truncate the incoming skb, but TCP stack was not really expecting this to happen. It probably was expecting a simple DROP or ACCEPT behavior. We first need to make sure no part of TCP header could be removed. Then we need to adjust TCP_SKB_CB(skb)->end_seq Many thanks to syzkaller team and Marco for giving us a reproducer. Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Marco Grassi <marco.gra@gmail.com> Reported-by: Vladis Dronov <vdronov@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-11-21ipv4: use new_gw for redirect neigh lookupStephen Suryaputra Lin
[ Upstream commit 969447f226b451c453ddc83cac6144eaeac6f2e3 ] In v2.6, ip_rt_redirect() calls arp_bind_neighbour() which returns 0 and then the state of the neigh for the new_gw is checked. If the state isn't valid then the redirected route is deleted. This behavior is maintained up to v3.5.7 by check_peer_redirect() because rt->rt_gateway is assigned to peer->redirect_learned.a4 before calling ipv4_neigh_lookup(). After commit 5943634fc559 ("ipv4: Maintain redirect and PMTU info in struct rtable again."), ipv4_neigh_lookup() is performed without the rt_gateway assigned to the new_gw. In the case when rt_gateway (old_gw) isn't zero, the function uses it as the key. The neigh is most likely valid since the old_gw is the one that sends the ICMP redirect message. Then the new_gw is assigned to fib_nh_exception. The problem is: the new_gw ARP may never gets resolved and the traffic is blackholed. So, use the new_gw for neigh lookup. Changes from v1: - use __ipv4_neigh_lookup instead (per Eric Dumazet). Fixes: 5943634fc559 ("ipv4: Maintain redirect and PMTU info in struct rtable again.") Signed-off-by: Stephen Suryaputra Lin <ssurya@ieee.org> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-11-21fib_trie: Correct /proc/net/route off by one errorAlexander Duyck
[ Upstream commit fd0285a39b1cb496f60210a9a00ad33a815603e7 ] The display of /proc/net/route has had a couple issues due to the fact that when I originally rewrote most of fib_trie I made it so that the iterator was tracking the next value to use instead of the current. In addition it had an off by 1 error where I was tracking the first piece of data as position 0, even though in reality that belonged to the SEQ_START_TOKEN. This patch updates the code so the iterator tracks the last reported position and key instead of the next expected position and key. In addition it shifts things so that all of the leaves start at 1 instead of trying to report leaves starting with offset 0 as being valid. With these two issues addressed this should resolve any off by one errors that were present in the display of /proc/net/route. Fixes: 25b97c016b26 ("ipv4: off-by-one in continuation handling in /proc/net/route") Cc: Andy Whitcroft <apw@canonical.com> Reported-by: Jason Baron <jbaron@akamai.com> Tested-by: Jason Baron <jbaron@akamai.com> Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-11-21tcp: fix potential memory corruptionEric Dumazet
[ Upstream commit ac9e70b17ecd7c6e933ff2eaf7ab37429e71bf4d ] Imagine initial value of max_skb_frags is 17, and last skb in write queue has 15 frags. Then max_skb_frags is lowered to 14 or smaller value. tcp_sendmsg() will then be allowed to add additional page frags and eventually go past MAX_SKB_FRAGS, overflowing struct skb_shared_info. Fixes: 5f74f82ea34c ("net:Add sysctl_max_skb_frags") Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Hans Westgaard Ry <hans.westgaard.ry@oracle.com> Cc: Håkon Bugge <haakon.bugge@oracle.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-11-21dctcp: avoid bogus doubling of cwnd after lossFlorian Westphal
[ Upstream commit ce6dd23329b1ee6a794acf5f7e40f8e89b8317ee ] If a congestion control module doesn't provide .undo_cwnd function, tcp_undo_cwnd_reduction() will set cwnd to tp->snd_cwnd = max(tp->snd_cwnd, tp->snd_ssthresh << 1); ... which makes sense for reno (it sets ssthresh to half the current cwnd), but it makes no sense for dctcp, which sets ssthresh based on the current congestion estimate. This can cause severe growth of cwnd (eventually overflowing u32). Fix this by saving last cwnd on loss and restore cwnd based on that, similar to cubic and other algorithms. Fixes: e3118e8359bb7c ("net: tcp: add DCTCP congestion control algorithm") Cc: Lawrence Brakmo <brakmo@fb.com> Cc: Andrew Shewmaker <agshew@gmail.com> Cc: Glenn Judd <glenn.judd@morganstanley.com> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-11-15udp: fix IP_CHECKSUM handlingEric Dumazet
[ Upstream commit 10df8e6152c6c400a563a673e9956320bfce1871 ] First bug was added in commit ad6f939ab193 ("ip: Add offset parameter to ip_cmsg_recv") : Tom missed that ipv4 udp messages could be received on AF_INET6 socket. ip_cmsg_recv(msg, skb) should have been replaced by ip_cmsg_recv_offset(msg, skb, sizeof(struct udphdr)); Then commit e6afc8ace6dd ("udp: remove headers from UDP packets before queueing") forgot to adjust the offsets now UDP headers are pulled before skb are put in receive queue. Fixes: ad6f939ab193 ("ip: Add offset parameter to ip_cmsg_recv") Fixes: e6afc8ace6dd ("udp: remove headers from UDP packets before queueing") Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Sam Kumar <samanthakumar@google.com> Cc: Willem de Bruijn <willemb@google.com> Tested-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>
2016-11-15ipv4: use the right lock for ping_group_rangeWANG Cong
[ Upstream commit 396a30cce15d084b2b1a395aa6d515c3d559c674 ] This reverts commit a681574c99be23e4d20b769bf0e543239c364af5 ("ipv4: disable BH in set_ping_group_range()") because we never read ping_group_range in BH context (unlike local_port_range). Then, since we already have a lock for ping_group_range, those using ip_local_ports.lock for ping_group_range are clearly typos. We might consider to share a same lock for both ping_group_range and local_port_range w.r.t. space saving, but that should be for net-next. Fixes: a681574c99be ("ipv4: disable BH in set_ping_group_range()") Fixes: ba6b918ab234 ("ping: move ping_group_range out of CONFIG_SYSCTL") Cc: Eric Dumazet <edumazet@google.com> Cc: Eric Salo <salo@google.com> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-11-15ipv4: disable BH in set_ping_group_range()Eric Dumazet
[ Upstream commit a681574c99be23e4d20b769bf0e543239c364af5 ] In commit 4ee3bd4a8c746 ("ipv4: disable BH when changing ip local port range") Cong added BH protection in set_local_port_range() but missed that same fix was needed in set_ping_group_range() Fixes: b8f1a55639e6 ("udp: Add function to make source port for UDP tunnels") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Eric Salo <salo@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-11-15net: add recursion limit to GROSabrina Dubroca
[ Upstream commit fcd91dd449867c6bfe56a81cabba76b829fd05cd ] Currently, GRO can do unlimited recursion through the gro_receive handlers. This was fixed for tunneling protocols by limiting tunnel GRO to one level with encap_mark, but both VLAN and TEB still have this problem. Thus, the kernel is vulnerable to a stack overflow, if we receive a packet composed entirely of VLAN headers. This patch adds a recursion counter to the GRO layer to prevent stack overflow. When a gro_receive function hits the recursion limit, GRO is aborted for this skb and it is processed normally. This recursion counter is put in the GRO CB, but could be turned into a percpu counter if we run out of space in the CB. Thanks to Vladimír Beneš <vbenes@redhat.com> for the initial bug report. Fixes: CVE-2016-7039 Fixes: 9b174d88c257 ("net: Add Transparent Ethernet Bridging GRO support.") Fixes: 66e5133f19e9 ("vlan: Add GRO support for non hardware accelerated vlan") Signed-off-by: Sabrina Dubroca <sd@queasysnail.net> Reviewed-by: Jiri Benc <jbenc@redhat.com> Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Acked-by: Tom Herbert <tom@herbertland.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-11-15ipmr, ip6mr: fix scheduling while atomic and a deadlock with ipmr_get_routeNikolay Aleksandrov
[ Upstream commit 2cf750704bb6d7ed8c7d732e071dd1bc890ea5e8 ] Since the commit below the ipmr/ip6mr rtnl_unicast() code uses the portid instead of the previous dst_pid which was copied from in_skb's portid. Since the skb is new the portid is 0 at that point so the packets are sent to the kernel and we get scheduling while atomic or a deadlock (depending on where it happens) by trying to acquire rtnl two times. Also since this is RTM_GETROUTE, it can be triggered by a normal user. Here's the sleeping while atomic trace: [ 7858.212557] BUG: sleeping function called from invalid context at kernel/locking/mutex.c:620 [ 7858.212748] in_atomic(): 1, irqs_disabled(): 0, pid: 0, name: swapper/0 [ 7858.212881] 2 locks held by swapper/0/0: [ 7858.213013] #0: (((&mrt->ipmr_expire_timer))){+.-...}, at: [<ffffffff810fbbf5>] call_timer_fn+0x5/0x350 [ 7858.213422] #1: (mfc_unres_lock){+.....}, at: [<ffffffff8161e005>] ipmr_expire_process+0x25/0x130 [ 7858.213807] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.8.0-rc7+ #179 [ 7858.213934] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.7.5-20140531_083030-gandalf 04/01/2014 [ 7858.214108] 0000000000000000 ffff88005b403c50 ffffffff813a7804 0000000000000000 [ 7858.214412] ffffffff81a1338e ffff88005b403c78 ffffffff810a4a72 ffffffff81a1338e [ 7858.214716] 000000000000026c 0000000000000000 ffff88005b403ca8 ffffffff810a4b9f [ 7858.215251] Call Trace: [ 7858.215412] <IRQ> [<ffffffff813a7804>] dump_stack+0x85/0xc1 [ 7858.215662] [<ffffffff810a4a72>] ___might_sleep+0x192/0x250 [ 7858.215868] [<ffffffff810a4b9f>] __might_sleep+0x6f/0x100 [ 7858.216072] [<ffffffff8165bea3>] mutex_lock_nested+0x33/0x4d0 [ 7858.216279] [<ffffffff815a7a5f>] ? netlink_lookup+0x25f/0x460 [ 7858.216487] [<ffffffff8157474b>] rtnetlink_rcv+0x1b/0x40 [ 7858.216687] [<ffffffff815a9a0c>] netlink_unicast+0x19c/0x260 [ 7858.216900] [<ffffffff81573c70>] rtnl_unicast+0x20/0x30 [ 7858.217128] [<ffffffff8161cd39>] ipmr_destroy_unres+0xa9/0xf0 [ 7858.217351] [<ffffffff8161e06f>] ipmr_expire_process+0x8f/0x130 [ 7858.217581] [<ffffffff8161dfe0>] ? ipmr_net_init+0x180/0x180 [ 7858.217785] [<ffffffff8161dfe0>] ? ipmr_net_init+0x180/0x180 [ 7858.217990] [<ffffffff810fbc95>] call_timer_fn+0xa5/0x350 [ 7858.218192] [<ffffffff810fbbf5>] ? call_timer_fn+0x5/0x350 [ 7858.218415] [<ffffffff8161dfe0>] ? ipmr_net_init+0x180/0x180 [ 7858.218656] [<ffffffff810fde10>] run_timer_softirq+0x260/0x640 [ 7858.218865] [<ffffffff8166379b>] ? __do_softirq+0xbb/0x54f [ 7858.219068] [<ffffffff816637c8>] __do_softirq+0xe8/0x54f [ 7858.219269] [<ffffffff8107a948>] irq_exit+0xb8/0xc0 [ 7858.219463] [<ffffffff81663452>] smp_apic_timer_interrupt+0x42/0x50 [ 7858.219678] [<ffffffff816625bc>] apic_timer_interrupt+0x8c/0xa0 [ 7858.219897] <EOI> [<ffffffff81055f16>] ? native_safe_halt+0x6/0x10 [ 7858.220165] [<ffffffff810d64dd>] ? trace_hardirqs_on+0xd/0x10 [ 7858.220373] [<ffffffff810298e3>] default_idle+0x23/0x190 [ 7858.220574] [<ffffffff8102a20f>] arch_cpu_idle+0xf/0x20 [ 7858.220790] [<ffffffff810c9f8c>] default_idle_call+0x4c/0x60 [ 7858.221016] [<ffffffff810ca33b>] cpu_startup_entry+0x39b/0x4d0 [ 7858.221257] [<ffffffff8164f995>] rest_init+0x135/0x140 [ 7858.221469] [<ffffffff81f83014>] start_kernel+0x50e/0x51b [ 7858.221670] [<ffffffff81f82120>] ? early_idt_handler_array+0x120/0x120 [ 7858.221894] [<ffffffff81f8243f>] x86_64_start_reservations+0x2a/0x2c [ 7858.222113] [<ffffffff81f8257c>] x86_64_start_kernel+0x13b/0x14a Fixes: 2942e9005056 ("[RTNETLINK]: Use rtnl_unicast() for rtnetlink unicasts") Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-11-15tcp: fix a compile error in DBGUNDO()Eric Dumazet
[ Upstream commit 019b1c9fe32a2a32c1153e31375f87ec3e591273 ] If DBGUNDO() is enabled (FASTRETRANS_DEBUG > 1), a compile error will happen, since inet6_sk(sk)->daddr became sk->sk_v6_daddr Fixes: efe4208f47f9 ("ipv6: make lookups simpler and faster") 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>
2016-11-15tcp: fix wrong checksum calculation on MTU probingDouglas Caetano dos Santos
[ Upstream commit 2fe664f1fcf7c4da6891f95708a7a56d3c024354 ] With TCP MTU probing enabled and offload TX checksumming disabled, tcp_mtu_probe() calculated the wrong checksum when a fragment being copied into the probe's SKB had an odd length. This was caused by the direct use of skb_copy_and_csum_bits() to calculate the checksum, as it pads the fragment being copied, if needed. When this fragment was not the last, a subsequent call used the previous checksum without considering this padding. The effect was a stale connection in one way, as even retransmissions wouldn't solve the problem, because the checksum was never recalculated for the full SKB length. Signed-off-by: Douglas Caetano dos Santos <douglascs@taghos.com.br> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-11-15tcp: fix overflow in __tcp_retransmit_skb()Eric Dumazet
[ Upstream commit ffb4d6c8508657824bcef68a36b2a0f9d8c09d10 ] If a TCP socket gets a large write queue, an overflow can happen in a test in __tcp_retransmit_skb() preventing all retransmits. The flow then stalls and resets after timeouts. Tested: sysctl -w net.core.wmem_max=1000000000 netperf -H dest -- -s 1000000000 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>
generated by cgit v1.2.3 (git 2.0.4) at 2025-09-18 08:02:47 +0000