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2018-07-28ip: hash fragments consistentlyPaolo Abeni
[ Upstream commit 3dd1c9a1270736029ffca670e9bd0265f4120600 ] The skb hash for locally generated ip[v6] fragments belonging to the same datagram can vary in several circumstances: * for connected UDP[v6] sockets, the first fragment get its hash via set_owner_w()/skb_set_hash_from_sk() * for unconnected IPv6 UDPv6 sockets, the first fragment can get its hash via ip6_make_flowlabel()/skb_get_hash_flowi6(), if auto_flowlabel is enabled For the following frags the hash is usually computed via skb_get_hash(). The above can cause OoO for unconnected IPv6 UDPv6 socket: in that scenario the egress tx queue can be selected on a per packet basis via the skb hash. It may also fool flow-oriented schedulers to place fragments belonging to the same datagram in different flows. Fix the issue by copying the skb hash from the head frag into the others at fragmentation time. Before this commit: perf probe -a "dev_queue_xmit skb skb->hash skb->l4_hash:b1@0/8 skb->sw_hash:b1@1/8" netperf -H $IPV4 -t UDP_STREAM -l 5 -- -m 2000 -n & perf record -e probe:dev_queue_xmit -e probe:skb_set_owner_w -a sleep 0.1 perf script probe:dev_queue_xmit: (ffffffff8c6b1b20) hash=3713014309 l4_hash=1 sw_hash=0 probe:dev_queue_xmit: (ffffffff8c6b1b20) hash=0 l4_hash=0 sw_hash=0 After this commit: probe:dev_queue_xmit: (ffffffff8c6b1b20) hash=2171763177 l4_hash=1 sw_hash=0 probe:dev_queue_xmit: (ffffffff8c6b1b20) hash=2171763177 l4_hash=1 sw_hash=0 Fixes: b73c3d0e4f0e ("net: Save TX flow hash in sock and set in skbuf on xmit") Fixes: 67800f9b1f4e ("ipv6: Call skb_get_hash_flowi6 to get skb->hash in ip6_make_flowlabel") Signed-off-by: Paolo Abeni <pabeni@redhat.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-06-13vrf: check the original netdevice for generating redirectStephen Suryaputra
[ Upstream commit 2f17becfbea5e9a0529b51da7345783e96e69516 ] Use the right device to determine if redirect should be sent especially when using vrf. Same as well as when sending the redirect. Signed-off-by: Stephen Suryaputra <ssuryaextr@gmail.com> Acked-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-25net: test tailroom before appending to linear skbWillem de Bruijn
[ Upstream commit 113f99c3358564a0647d444c2ae34e8b1abfd5b9 ] Device features may change during transmission. In particular with corking, a device may toggle scatter-gather in between allocating and writing to an skb. Do not unconditionally assume that !NETIF_F_SG at write time implies that the same held at alloc time and thus the skb has sufficient tailroom. This issue predates git history. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Reported-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Willem de Bruijn <willemb@google.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-04-13net/ipv6: Increment OUTxxx counters after netfilter hookJeff Barnhill
[ Upstream commit 71a1c915238c970cd9bdd5bf158b1279d6b6d55b ] At the end of ip6_forward(), IPSTATS_MIB_OUTFORWDATAGRAMS and IPSTATS_MIB_OUTOCTETS are incremented immediately before the NF_HOOK call for NFPROTO_IPV6 / NF_INET_FORWARD. As a result, these counters get incremented regardless of whether or not the netfilter hook allows the packet to continue being processed. This change increments the counters in ip6_forward_finish() so that it will not happen if the netfilter hook chooses to terminate the packet, which is similar to how IPv4 works. Signed-off-by: Jeff Barnhill <0xeffeff@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-04-13ipv6: the entire IPv6 header chain must fit the first fragmentPaolo Abeni
[ Upstream commit 10b8a3de603df7b96004179b1b33b1708c76d144 ] While building ipv6 datagram we currently allow arbitrary large extheaders, even beyond pmtu size. The syzbot has found a way to exploit the above to trigger the following splat: kernel BUG at ./include/linux/skbuff.h:2073! invalid opcode: 0000 [#1] SMP KASAN Dumping ftrace buffer: (ftrace buffer empty) Modules linked in: CPU: 1 PID: 4230 Comm: syzkaller672661 Not tainted 4.16.0-rc2+ #326 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:__skb_pull include/linux/skbuff.h:2073 [inline] RIP: 0010:__ip6_make_skb+0x1ac8/0x2190 net/ipv6/ip6_output.c:1636 RSP: 0018:ffff8801bc18f0f0 EFLAGS: 00010293 RAX: ffff8801b17400c0 RBX: 0000000000000738 RCX: ffffffff84f01828 RDX: 0000000000000000 RSI: 0000000000000001 RDI: ffff8801b415ac18 RBP: ffff8801bc18f360 R08: ffff8801b4576844 R09: 0000000000000000 R10: ffff8801bc18f380 R11: ffffed00367aee4e R12: 00000000000000d6 R13: ffff8801b415a740 R14: dffffc0000000000 R15: ffff8801b45767c0 FS: 0000000001535880(0000) GS:ffff8801db300000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000002000b000 CR3: 00000001b4123001 CR4: 00000000001606e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: ip6_finish_skb include/net/ipv6.h:969 [inline] udp_v6_push_pending_frames+0x269/0x3b0 net/ipv6/udp.c:1073 udpv6_sendmsg+0x2a96/0x3400 net/ipv6/udp.c:1343 inet_sendmsg+0x11f/0x5e0 net/ipv4/af_inet.c:764 sock_sendmsg_nosec net/socket.c:630 [inline] sock_sendmsg+0xca/0x110 net/socket.c:640 ___sys_sendmsg+0x320/0x8b0 net/socket.c:2046 __sys_sendmmsg+0x1ee/0x620 net/socket.c:2136 SYSC_sendmmsg net/socket.c:2167 [inline] SyS_sendmmsg+0x35/0x60 net/socket.c:2162 do_syscall_64+0x280/0x940 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x4404c9 RSP: 002b:00007ffdce35f948 EFLAGS: 00000217 ORIG_RAX: 0000000000000133 RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 00000000004404c9 RDX: 0000000000000003 RSI: 0000000020001f00 RDI: 0000000000000003 RBP: 00000000006cb018 R08: 00000000004002c8 R09: 00000000004002c8 R10: 0000000020000080 R11: 0000000000000217 R12: 0000000000401df0 R13: 0000000000401e80 R14: 0000000000000000 R15: 0000000000000000 Code: ff e8 1d 5e b9 fc e9 15 e9 ff ff e8 13 5e b9 fc e9 44 e8 ff ff e8 29 5e b9 fc e9 c0 e6 ff ff e8 3f f3 80 fc 0f 0b e8 38 f3 80 fc <0f> 0b 49 8d 87 80 00 00 00 4d 8d 87 84 00 00 00 48 89 85 20 fe RIP: __skb_pull include/linux/skbuff.h:2073 [inline] RSP: ffff8801bc18f0f0 RIP: __ip6_make_skb+0x1ac8/0x2190 net/ipv6/ip6_output.c:1636 RSP: ffff8801bc18f0f0 As stated by RFC 7112 section 5: When a host fragments an IPv6 datagram, it MUST include the entire IPv6 Header Chain in the First Fragment. So this patch addresses the issue dropping datagrams with excessive extheader length. It also updates the error path to report to the calling socket nonnegative pmtu values. The issue apparently predates git history. v1 -> v2: cleanup error path, as per Eric's suggestion Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Reported-by: syzbot+91e6f9932ff122fa4410@syzkaller.appspotmail.com Signed-off-by: Paolo Abeni <pabeni@redhat.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-01-31ipv6: ip6_make_skb() needs to clear cork.base.dstEric Dumazet
[ Upstream commit 95ef498d977bf44ac094778fd448b98af158a3e6 ] In my last patch, I missed fact that cork.base.dst was not initialized in ip6_make_skb() : If ip6_setup_cork() returns an error, we might attempt a dst_release() on some random pointer. Fixes: 862c03ee1deb ("ipv6: fix possible mem leaks in ipv6_make_skb()") 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>
2018-01-31ipv6: fix udpv6 sendmsg crash caused by too small MTUMike Maloney
[ Upstream commit 749439bfac6e1a2932c582e2699f91d329658196 ] The logic in __ip6_append_data() assumes that the MTU is at least large enough for the headers. A device's MTU may be adjusted after being added while sendmsg() is processing data, resulting in __ip6_append_data() seeing any MTU. For an mtu smaller than the size of the fragmentation header, the math results in a negative 'maxfraglen', which causes problems when refragmenting any previous skb in the skb_write_queue, leaving it possibly malformed. Instead sendmsg returns EINVAL when the mtu is calculated to be less than IPV6_MIN_MTU. Found by syzkaller: kernel BUG at ./include/linux/skbuff.h:2064! invalid opcode: 0000 [#1] SMP KASAN Dumping ftrace buffer: (ftrace buffer empty) Modules linked in: CPU: 1 PID: 14216 Comm: syz-executor5 Not tainted 4.13.0-rc4+ #2 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 task: ffff8801d0b68580 task.stack: ffff8801ac6b8000 RIP: 0010:__skb_pull include/linux/skbuff.h:2064 [inline] RIP: 0010:__ip6_make_skb+0x18cf/0x1f70 net/ipv6/ip6_output.c:1617 RSP: 0018:ffff8801ac6bf570 EFLAGS: 00010216 RAX: 0000000000010000 RBX: 0000000000000028 RCX: ffffc90003cce000 RDX: 00000000000001b8 RSI: ffffffff839df06f RDI: ffff8801d9478ca0 RBP: ffff8801ac6bf780 R08: ffff8801cc3f1dbc R09: 0000000000000000 R10: ffff8801ac6bf7a0 R11: 43cb4b7b1948a9e7 R12: ffff8801cc3f1dc8 R13: ffff8801cc3f1d40 R14: 0000000000001036 R15: dffffc0000000000 FS: 00007f43d740c700(0000) GS:ffff8801dc100000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f7834984000 CR3: 00000001d79b9000 CR4: 00000000001406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: ip6_finish_skb include/net/ipv6.h:911 [inline] udp_v6_push_pending_frames+0x255/0x390 net/ipv6/udp.c:1093 udpv6_sendmsg+0x280d/0x31a0 net/ipv6/udp.c:1363 inet_sendmsg+0x11f/0x5e0 net/ipv4/af_inet.c:762 sock_sendmsg_nosec net/socket.c:633 [inline] sock_sendmsg+0xca/0x110 net/socket.c:643 SYSC_sendto+0x352/0x5a0 net/socket.c:1750 SyS_sendto+0x40/0x50 net/socket.c:1718 entry_SYSCALL_64_fastpath+0x1f/0xbe RIP: 0033:0x4512e9 RSP: 002b:00007f43d740bc08 EFLAGS: 00000216 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 00000000007180a8 RCX: 00000000004512e9 RDX: 000000000000002e RSI: 0000000020d08000 RDI: 0000000000000005 RBP: 0000000000000086 R08: 00000000209c1000 R09: 000000000000001c R10: 0000000000040800 R11: 0000000000000216 R12: 00000000004b9c69 R13: 00000000ffffffff R14: 0000000000000005 R15: 00000000202c2000 Code: 9e 01 fe e9 c5 e8 ff ff e8 7f 9e 01 fe e9 4a ea ff ff 48 89 f7 e8 52 9e 01 fe e9 aa eb ff ff e8 a8 b6 cf fd 0f 0b e8 a1 b6 cf fd <0f> 0b 49 8d 45 78 4d 8d 45 7c 48 89 85 78 fe ff ff 49 8d 85 ba RIP: __skb_pull include/linux/skbuff.h:2064 [inline] RSP: ffff8801ac6bf570 RIP: __ip6_make_skb+0x18cf/0x1f70 net/ipv6/ip6_output.c:1617 RSP: ffff8801ac6bf570 Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: Mike Maloney <maloney@google.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-01-31ipv6: Fix getsockopt() for sockets with default IPV6_AUTOFLOWLABELBen Hutchings
[ Upstream commit e9191ffb65d8e159680ce0ad2224e1acbde6985c ] Commit 513674b5a2c9 ("net: reevalulate autoflowlabel setting after sysctl setting") removed the initialisation of ipv6_pinfo::autoflowlabel and added a second flag to indicate whether this field or the net namespace default should be used. The getsockopt() handling for this case was not updated, so it currently returns 0 for all sockets for which IPV6_AUTOFLOWLABEL is not explicitly enabled. Fix it to return the effective value, whether that has been set at the socket or net namespace level. Fixes: 513674b5a2c9 ("net: reevalulate autoflowlabel setting after sysctl ...") Signed-off-by: Ben Hutchings <ben.hutchings@codethink.co.uk> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-01-17ipv6: fix possible mem leaks in ipv6_make_skb()Eric Dumazet
[ Upstream commit 862c03ee1deb7e19e0f9931682e0294ecd1fcaf9 ] ip6_setup_cork() might return an error, while memory allocations have been done and must be rolled back. Fixes: 6422398c2ab0 ("ipv6: introduce ipv6_make_skb") Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Vlad Yasevich <vyasevich@gmail.com> Reported-by: Mike Maloney <maloney@google.com> Acked-by: Mike Maloney <maloney@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-01-02net: reevalulate autoflowlabel setting after sysctl settingShaohua Li
[ Upstream commit 513674b5a2c9c7a67501506419da5c3c77ac6f08 ] sysctl.ip6.auto_flowlabels is default 1. In our hosts, we set it to 2. If sockopt doesn't set autoflowlabel, outcome packets from the hosts are supposed to not include flowlabel. This is true for normal packet, but not for reset packet. The reason is ipv6_pinfo.autoflowlabel is set in sock creation. Later if we change sysctl.ip6.auto_flowlabels, the ipv6_pinfo.autoflowlabel isn't changed, so the sock will keep the old behavior in terms of auto flowlabel. Reset packet is suffering from this problem, because reset packet is sent from a special control socket, which is created at boot time. Since sysctl.ipv6.auto_flowlabels is 1 by default, the control socket will always have its ipv6_pinfo.autoflowlabel set, even after user set sysctl.ipv6.auto_flowlabels to 1, so reset packset will always have flowlabel. Normal sock created before sysctl setting suffers from the same issue. We can't even turn off autoflowlabel unless we kill all socks in the hosts. To fix this, if IPV6_AUTOFLOWLABEL sockopt is used, we use the autoflowlabel setting from user, otherwise we always call ip6_default_np_autolabel() which has the new settings of sysctl. Note, this changes behavior a little bit. Before commit 42240901f7c4 (ipv6: Implement different admin modes for automatic flow labels), the autoflowlabel behavior of a sock isn't sticky, eg, if sysctl changes, existing connection will change autoflowlabel behavior. After that commit, autoflowlabel behavior is sticky in the whole life of the sock. With this patch, the behavior isn't sticky again. Cc: Martin KaFai Lau <kafai@fb.com> Cc: Eric Dumazet <eric.dumazet@gmail.com> Cc: Tom Herbert <tom@quantonium.net> Signed-off-by: Shaohua Li <shli@fb.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-18ipv6: flowlabel: do not leave opt->tot_len with garbageEric Dumazet
[ Upstream commit 864e2a1f8aac05effac6063ce316b480facb46ff ] When syzkaller team brought us a C repro for the crash [1] that had been reported many times in the past, I finally could find the root cause. If FlowLabel info is merged by fl6_merge_options(), we leave part of the opt_space storage provided by udp/raw/l2tp with random value in opt_space.tot_len, unless a control message was provided at sendmsg() time. Then ip6_setup_cork() would use this random value to perform a kzalloc() call. Undefined behavior and crashes. Fix is to properly set tot_len in fl6_merge_options() At the same time, we can also avoid consuming memory and cpu cycles to clear it, if every option is copied via a kmemdup(). This is the change in ip6_setup_cork(). [1] kasan: CONFIG_KASAN_INLINE enabled kasan: GPF could be caused by NULL-ptr deref or user memory access general protection fault: 0000 [#1] SMP KASAN Dumping ftrace buffer: (ftrace buffer empty) Modules linked in: CPU: 0 PID: 6613 Comm: syz-executor0 Not tainted 4.14.0-rc4+ #127 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 task: ffff8801cb64a100 task.stack: ffff8801cc350000 RIP: 0010:ip6_setup_cork+0x274/0x15c0 net/ipv6/ip6_output.c:1168 RSP: 0018:ffff8801cc357550 EFLAGS: 00010203 RAX: dffffc0000000000 RBX: ffff8801cc357748 RCX: 0000000000000010 RDX: 0000000000000002 RSI: ffffffff842bd1d9 RDI: 0000000000000014 RBP: ffff8801cc357620 R08: ffff8801cb17f380 R09: ffff8801cc357b10 R10: ffff8801cb64a100 R11: 0000000000000000 R12: ffff8801cc357ab0 R13: ffff8801cc357b10 R14: 0000000000000000 R15: ffff8801c3bbf0c0 FS: 00007f9c5c459700(0000) GS:ffff8801db200000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000020324000 CR3: 00000001d1cf2000 CR4: 00000000001406f0 DR0: 0000000020001010 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600 Call Trace: ip6_make_skb+0x282/0x530 net/ipv6/ip6_output.c:1729 udpv6_sendmsg+0x2769/0x3380 net/ipv6/udp.c:1340 inet_sendmsg+0x11f/0x5e0 net/ipv4/af_inet.c:762 sock_sendmsg_nosec net/socket.c:633 [inline] sock_sendmsg+0xca/0x110 net/socket.c:643 SYSC_sendto+0x358/0x5a0 net/socket.c:1750 SyS_sendto+0x40/0x50 net/socket.c:1718 entry_SYSCALL_64_fastpath+0x1f/0xbe RIP: 0033:0x4520a9 RSP: 002b:00007f9c5c458c08 EFLAGS: 00000216 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 0000000000718000 RCX: 00000000004520a9 RDX: 0000000000000001 RSI: 0000000020fd1000 RDI: 0000000000000016 RBP: 0000000000000086 R08: 0000000020e0afe4 R09: 000000000000001c R10: 0000000000000000 R11: 0000000000000216 R12: 00000000004bb1ee R13: 00000000ffffffff R14: 0000000000000016 R15: 0000000000000029 Code: e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 ea 0f 00 00 48 8d 79 04 48 b8 00 00 00 00 00 fc ff df 45 8b 74 24 04 48 89 fa 48 c1 ea 03 <0f> b6 14 02 48 89 f8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 RIP: ip6_setup_cork+0x274/0x15c0 net/ipv6/ip6_output.c:1168 RSP: ffff8801cc357550 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>
2017-08-12udp: consistently apply ufo or fragmentationWillem de Bruijn
[ Upstream commit 85f1bd9a7b5a79d5baa8bf44af19658f7bf77bfa ] When iteratively building a UDP datagram with MSG_MORE and that datagram exceeds MTU, consistently choose UFO or fragmentation. Once skb_is_gso, always apply ufo. Conversely, once a datagram is split across multiple skbs, do not consider ufo. Sendpage already maintains the first invariant, only add the second. IPv6 does not have a sendpage implementation to modify. A gso skb must have a partial checksum, do not follow sk_no_check_tx in udp_send_skb. Found by syzkaller. Fixes: e89e9cf539a2 ("[IPv4/IPv6]: UFO Scatter-gather approach") Reported-by: Andrey Konovalov <andreyknvl@google.com> Signed-off-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>
2017-08-12revert "net: account for current skb length when deciding about UFO"Greg Kroah-Hartman
This reverts commit ef09c9ff343122a0b245416066992d096416ff19 which is commit a5cb659bbc1c8644efa0c3138a757a1e432a4880 upstream as it causes merge issues with later patches that are much more important... Cc: Michal Kubecek <mkubecek@suse.cz> Cc: Vlad Yasevich <vyasevic@redhat.com> Cc: David S. Miller <davem@davemloft.net> Cc: Sasha Levin <alexander.levin@verizon.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-08-11net: account for current skb length when deciding about UFOMichal Kubeček
[ Upstream commit a5cb659bbc1c8644efa0c3138a757a1e432a4880 ] Our customer encountered stuck NFS writes for blocks starting at specific offsets w.r.t. page boundary caused by networking stack sending packets via UFO enabled device with wrong checksum. The problem can be reproduced by composing a long UDP datagram from multiple parts using MSG_MORE flag: sendto(sd, buff, 1000, MSG_MORE, ...); sendto(sd, buff, 1000, MSG_MORE, ...); sendto(sd, buff, 3000, 0, ...); Assume this packet is to be routed via a device with MTU 1500 and NETIF_F_UFO enabled. When second sendto() gets into __ip_append_data(), this condition is tested (among others) to decide whether to call ip_ufo_append_data(): ((length + fragheaderlen) > mtu) || (skb && skb_is_gso(skb)) At the moment, we already have skb with 1028 bytes of data which is not marked for GSO so that the test is false (fragheaderlen is usually 20). Thus we append second 1000 bytes to this skb without invoking UFO. Third sendto(), however, has sufficient length to trigger the UFO path so that we end up with non-UFO skb followed by a UFO one. Later on, udp_send_skb() uses udp_csum() to calculate the checksum but that assumes all fragments have correct checksum in skb->csum which is not true for UFO fragments. When checking against MTU, we need to add skb->len to length of new segment if we already have a partially filled skb and fragheaderlen only if there isn't one. In the IPv6 case, skb can only be null if this is the first segment so that we have to use headersize (length of the first IPv6 header) rather than fragheaderlen (length of IPv6 header of further fragments) for skb == NULL. Fixes: e89e9cf539a2 ("[IPv4/IPv6]: UFO Scatter-gather approach") Fixes: e4c5e13aa45c ("ipv6: Should use consistent conditional judgement for ip6 fragment between __ip6_append_data and ip6_finish_output") Signed-off-by: Michal Kubecek <mkubecek@suse.cz> Acked-by: Vlad Yasevich <vyasevic@redhat.com> 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>
2017-08-11ipv6: Don't increase IPSTATS_MIB_FRAGFAILS twice in ip6_fragment()Stefano Brivio
[ Upstream commit afce615aaabfbaad02550e75c0bec106dafa1adf ] RFC 2465 defines ipv6IfStatsOutFragFails as: "The number of IPv6 datagrams that have been discarded because they needed to be fragmented at this output interface but could not be." The existing implementation, instead, would increase the counter twice in case we fail to allocate room for single fragments: once for the fragment, once for the datagram. This didn't look intentional though. In one of the two affected affected failure paths, the double increase was simply a result of a new 'goto fail' statement, introduced to avoid a skb leak. The other path appears to be affected since at least 2.6.12-rc2. Reported-by: Sabrina Dubroca <sdubroca@redhat.com> Fixes: 1d325d217c7f ("ipv6: ip6_fragment: fix headroom tests and skb leak") Signed-off-by: Stefano Brivio <sbrivio@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-08-06ipv6: Should use consistent conditional judgement for ip6 fragment between ↵Zheng Li
__ip6_append_data and ip6_finish_output [ Upstream commit e4c5e13aa45c23692e4acf56f0b3533f328199b2 ] There is an inconsistent conditional judgement between __ip6_append_data and ip6_finish_output functions, the variable length in __ip6_append_data just include the length of application's payload and udp6 header, don't include the length of ipv6 header, but in ip6_finish_output use (skb->len > ip6_skb_dst_mtu(skb)) as judgement, and skb->len include the length of ipv6 header. That causes some particular application's udp6 payloads whose length are between (MTU - IPv6 Header) and MTU were fragmented by ip6_fragment even though the rst->dev support UFO feature. Add the length of ipv6 header to length in __ip6_append_data to keep consistent conditional judgement as ip6_finish_output for ip6 fragment. Signed-off-by: Zheng Li <james.z.li@ericsson.com> 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>
2017-07-05ipv6: release dst on error in ip6_dst_lookup_tailWillem de Bruijn
commit 00ea1ceebe0d9f2dc1cc2b7bd575a00100c27869 upstream. If ip6_dst_lookup_tail has acquired a dst and fails the IPv4-mapped check, release the dst before returning an error. Fixes: ec5e3b0a1d41 ("ipv6: Inhibit IPv4-mapped src address on the wire.") Signed-off-by: Willem de Bruijn <willemb@google.com> Acked-by: Eric Dumazet <edumazet@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>
2017-06-17ipv6: Inhibit IPv4-mapped src address on the wire.Jonathan T. Leighton
[ Upstream commit ec5e3b0a1d41fbda0cc33a45bc9e54e91d9d12c7 ] This patch adds a check for the problematic case of an IPv4-mapped IPv6 source address and a destination address that is neither an IPv4-mapped IPv6 address nor in6addr_any, and returns an appropriate error. The check in done before returning from looking up the route. Signed-off-by: Jonathan T. Leighton <jtleight@udel.edu> 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>
2017-06-07ipv6: fix out of bound writes in __ip6_append_data()Eric Dumazet
[ Upstream commit 232cd35d0804cc241eb887bb8d4d9b3b9881c64a ] Andrey Konovalov and idaifish@gmail.com reported crashes caused by one skb shared_info being overwritten from __ip6_append_data() Andrey program lead to following state : copy -4200 datalen 2000 fraglen 2040 maxfraglen 2040 alloclen 2048 transhdrlen 0 offset 0 fraggap 6200 The skb_copy_and_csum_bits(skb_prev, maxfraglen, data + transhdrlen, fraggap, 0); is overwriting skb->head and skb_shared_info Since we apparently detect this rare condition too late, move the code earlier to even avoid allocating skb and risking crashes. Once again, many thanks to Andrey and syzkaller team. Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Andrey Konovalov <andreyknvl@google.com> Tested-by: Andrey Konovalov <andreyknvl@google.com> Reported-by: <idaifish@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-07ipv6: Check ip6_find_1stfragopt() return value properly.David S. Miller
[ Upstream commit 7dd7eb9513bd02184d45f000ab69d78cb1fa1531 ] Do not use unsigned variables to see if it returns a negative error or not. Fixes: 2423496af35d ("ipv6: Prevent overrun when parsing v6 header options") Reported-by: Julia Lawall <julia.lawall@lip6.fr> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-07ipv6: Prevent overrun when parsing v6 header optionsCraig Gallek
[ Upstream commit 2423496af35d94a87156b063ea5cedffc10a70a1 ] The KASAN warning repoted below was discovered with a syzkaller program. The reproducer is basically: int s = socket(AF_INET6, SOCK_RAW, NEXTHDR_HOP); send(s, &one_byte_of_data, 1, MSG_MORE); send(s, &more_than_mtu_bytes_data, 2000, 0); The socket() call sets the nexthdr field of the v6 header to NEXTHDR_HOP, the first send call primes the payload with a non zero byte of data, and the second send call triggers the fragmentation path. The fragmentation code tries to parse the header options in order to figure out where to insert the fragment option. Since nexthdr points to an invalid option, the calculation of the size of the network header can made to be much larger than the linear section of the skb and data is read outside of it. This fix makes ip6_find_1stfrag return an error if it detects running out-of-bounds. [ 42.361487] ================================================================== [ 42.364412] BUG: KASAN: slab-out-of-bounds in ip6_fragment+0x11c8/0x3730 [ 42.365471] Read of size 840 at addr ffff88000969e798 by task ip6_fragment-oo/3789 [ 42.366469] [ 42.366696] CPU: 1 PID: 3789 Comm: ip6_fragment-oo Not tainted 4.11.0+ #41 [ 42.367628] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.1-1ubuntu1 04/01/2014 [ 42.368824] Call Trace: [ 42.369183] dump_stack+0xb3/0x10b [ 42.369664] print_address_description+0x73/0x290 [ 42.370325] kasan_report+0x252/0x370 [ 42.370839] ? ip6_fragment+0x11c8/0x3730 [ 42.371396] check_memory_region+0x13c/0x1a0 [ 42.371978] memcpy+0x23/0x50 [ 42.372395] ip6_fragment+0x11c8/0x3730 [ 42.372920] ? nf_ct_expect_unregister_notifier+0x110/0x110 [ 42.373681] ? ip6_copy_metadata+0x7f0/0x7f0 [ 42.374263] ? ip6_forward+0x2e30/0x2e30 [ 42.374803] ip6_finish_output+0x584/0x990 [ 42.375350] ip6_output+0x1b7/0x690 [ 42.375836] ? ip6_finish_output+0x990/0x990 [ 42.376411] ? ip6_fragment+0x3730/0x3730 [ 42.376968] ip6_local_out+0x95/0x160 [ 42.377471] ip6_send_skb+0xa1/0x330 [ 42.377969] ip6_push_pending_frames+0xb3/0xe0 [ 42.378589] rawv6_sendmsg+0x2051/0x2db0 [ 42.379129] ? rawv6_bind+0x8b0/0x8b0 [ 42.379633] ? _copy_from_user+0x84/0xe0 [ 42.380193] ? debug_check_no_locks_freed+0x290/0x290 [ 42.380878] ? ___sys_sendmsg+0x162/0x930 [ 42.381427] ? rcu_read_lock_sched_held+0xa3/0x120 [ 42.382074] ? sock_has_perm+0x1f6/0x290 [ 42.382614] ? ___sys_sendmsg+0x167/0x930 [ 42.383173] ? lock_downgrade+0x660/0x660 [ 42.383727] inet_sendmsg+0x123/0x500 [ 42.384226] ? inet_sendmsg+0x123/0x500 [ 42.384748] ? inet_recvmsg+0x540/0x540 [ 42.385263] sock_sendmsg+0xca/0x110 [ 42.385758] SYSC_sendto+0x217/0x380 [ 42.386249] ? SYSC_connect+0x310/0x310 [ 42.386783] ? __might_fault+0x110/0x1d0 [ 42.387324] ? lock_downgrade+0x660/0x660 [ 42.387880] ? __fget_light+0xa1/0x1f0 [ 42.388403] ? __fdget+0x18/0x20 [ 42.388851] ? sock_common_setsockopt+0x95/0xd0 [ 42.389472] ? SyS_setsockopt+0x17f/0x260 [ 42.390021] ? entry_SYSCALL_64_fastpath+0x5/0xbe [ 42.390650] SyS_sendto+0x40/0x50 [ 42.391103] entry_SYSCALL_64_fastpath+0x1f/0xbe [ 42.391731] RIP: 0033:0x7fbbb711e383 [ 42.392217] RSP: 002b:00007ffff4d34f28 EFLAGS: 00000246 ORIG_RAX: 000000000000002c [ 42.393235] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fbbb711e383 [ 42.394195] RDX: 0000000000001000 RSI: 00007ffff4d34f60 RDI: 0000000000000003 [ 42.395145] RBP: 0000000000000046 R08: 00007ffff4d34f40 R09: 0000000000000018 [ 42.396056] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000400aad [ 42.396598] R13: 0000000000000066 R14: 00007ffff4d34ee0 R15: 00007fbbb717af00 [ 42.397257] [ 42.397411] Allocated by task 3789: [ 42.397702] save_stack_trace+0x16/0x20 [ 42.398005] save_stack+0x46/0xd0 [ 42.398267] kasan_kmalloc+0xad/0xe0 [ 42.398548] kasan_slab_alloc+0x12/0x20 [ 42.398848] __kmalloc_node_track_caller+0xcb/0x380 [ 42.399224] __kmalloc_reserve.isra.32+0x41/0xe0 [ 42.399654] __alloc_skb+0xf8/0x580 [ 42.400003] sock_wmalloc+0xab/0xf0 [ 42.400346] __ip6_append_data.isra.41+0x2472/0x33d0 [ 42.400813] ip6_append_data+0x1a8/0x2f0 [ 42.401122] rawv6_sendmsg+0x11ee/0x2db0 [ 42.401505] inet_sendmsg+0x123/0x500 [ 42.401860] sock_sendmsg+0xca/0x110 [ 42.402209] ___sys_sendmsg+0x7cb/0x930 [ 42.402582] __sys_sendmsg+0xd9/0x190 [ 42.402941] SyS_sendmsg+0x2d/0x50 [ 42.403273] entry_SYSCALL_64_fastpath+0x1f/0xbe [ 42.403718] [ 42.403871] Freed by task 1794: [ 42.404146] save_stack_trace+0x16/0x20 [ 42.404515] save_stack+0x46/0xd0 [ 42.404827] kasan_slab_free+0x72/0xc0 [ 42.405167] kfree+0xe8/0x2b0 [ 42.405462] skb_free_head+0x74/0xb0 [ 42.405806] skb_release_data+0x30e/0x3a0 [ 42.406198] skb_release_all+0x4a/0x60 [ 42.406563] consume_skb+0x113/0x2e0 [ 42.406910] skb_free_datagram+0x1a/0xe0 [ 42.407288] netlink_recvmsg+0x60d/0xe40 [ 42.407667] sock_recvmsg+0xd7/0x110 [ 42.408022] ___sys_recvmsg+0x25c/0x580 [ 42.408395] __sys_recvmsg+0xd6/0x190 [ 42.408753] SyS_recvmsg+0x2d/0x50 [ 42.409086] entry_SYSCALL_64_fastpath+0x1f/0xbe [ 42.409513] [ 42.409665] The buggy address belongs to the object at ffff88000969e780 [ 42.409665] which belongs to the cache kmalloc-512 of size 512 [ 42.410846] The buggy address is located 24 bytes inside of [ 42.410846] 512-byte region [ffff88000969e780, ffff88000969e980) [ 42.411941] The buggy address belongs to the page: [ 42.412405] page:ffffea000025a780 count:1 mapcount:0 mapping: (null) index:0x0 compound_mapcount: 0 [ 42.413298] flags: 0x100000000008100(slab|head) [ 42.413729] raw: 0100000000008100 0000000000000000 0000000000000000 00000001800c000c [ 42.414387] raw: ffffea00002a9500 0000000900000007 ffff88000c401280 0000000000000000 [ 42.415074] page dumped because: kasan: bad access detected [ 42.415604] [ 42.415757] Memory state around the buggy address: [ 42.416222] ffff88000969e880: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 42.416904] ffff88000969e900: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 42.417591] >ffff88000969e980: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 42.418273] ^ [ 42.418588] ffff88000969ea00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 42.419273] ffff88000969ea80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 42.419882] ================================================================== Reported-by: Andrey Konovalov <andreyknvl@google.com> Signed-off-by: Craig Gallek <kraig@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-03-22ipv6: avoid write to a possibly cloned skbFlorian Westphal
[ Upstream commit 79e49503efe53a8c51d8b695bedc8a346c5e4a87 ] ip6_fragment, in case skb has a fraglist, checks if the skb is cloned. If it is, it will move to the 'slow path' and allocates new skbs for each fragment. However, right before entering the slowpath loop, it updates the nexthdr value of the last ipv6 extension header to NEXTHDR_FRAGMENT, to account for the fragment header that will be inserted in the new ipv6-fragment skbs. In case original skb is cloned this munges nexthdr value of another skb. Avoid this by doing the nexthdr update for each of the new fragment skbs separately. This was observed with tcpdump on a bridge device where netfilter ipv6 reassembly is active: tcpdump shows malformed fragment headers as the l4 header (icmpv6, tcp, etc). is decoded as a fragment header. Cc: Hannes Frederic Sowa <hannes@stressinduktion.org> Reported-by: Andreas Karis <akaris@redhat.com> 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>
2017-02-18tcp: don't annotate mark on control socket from tcp_v6_send_response()Pablo Neira
commit 92e55f412cffd016cc245a74278cb4d7b89bb3bc upstream. Unlike ipv4, this control socket is shared by all cpus so we cannot use it as scratchpad area to annotate the mark that we pass to ip6_xmit(). Add a new parameter to ip6_xmit() to indicate the mark. The SCTP socket family caches the flowi6 structure in the sctp_transport structure, so we cannot use to carry the mark unless we later on reset it back, which I discarded since it looks ugly to me. Fixes: bf99b4ded5f8 ("tcp: fix mark propagation with fwmark_reflect enabled") Suggested-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-10-31ipv6: Don't use ufo handling on later transformed packetsJakub Sitnicki
Similar to commit c146066ab802 ("ipv4: Don't use ufo handling on later transformed packets"), don't perform UFO on packets that will be IPsec transformed. To detect it we rely on the fact that headerlen in dst_entry is non-zero only for transformation bundles (xfrm_dst objects). Unwanted segmentation can be observed with a NETIF_F_UFO capable device, such as a dummy device: DEV=dum0 LEN=1493 ip li add $DEV type dummy ip addr add fc00::1/64 dev $DEV nodad ip link set $DEV up ip xfrm policy add dir out src fc00::1 dst fc00::2 \ tmpl src fc00::1 dst fc00::2 proto esp spi 1 ip xfrm state add src fc00::1 dst fc00::2 \ proto esp spi 1 enc 'aes' 0x0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b tcpdump -n -nn -i $DEV -t & socat /dev/zero,readbytes=$LEN udp6:[fc00::2]:$LEN tcpdump output before: IP6 fc00::1 > fc00::2: frag (0|1448) ESP(spi=0x00000001,seq=0x1), length 1448 IP6 fc00::1 > fc00::2: frag (1448|48) IP6 fc00::1 > fc00::2: ESP(spi=0x00000001,seq=0x2), length 88 ... and after: IP6 fc00::1 > fc00::2: frag (0|1448) ESP(spi=0x00000001,seq=0x1), length 1448 IP6 fc00::1 > fc00::2: frag (1448|80) Fixes: e89e9cf539a2 ("[IPv4/IPv6]: UFO Scatter-gather approach") Signed-off-by: Jakub Sitnicki <jkbs@redhat.com> Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-10net: ipv6: Remove l3mdev_get_saddr6David Ahern
No longer needed Signed-off-by: David Ahern <dsa@cumulusnetworks.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-10net: l3mdev: remove redundant callsDavid Ahern
A previous patch added l3mdev flow update making these hooks redundant. Remove them. Signed-off-by: David Ahern <dsa@cumulusnetworks.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-10net: l3mdev: Add hook to output pathDavid Ahern
This patch adds the infrastructure to the output path to pass an skb to an l3mdev device if it has a hook registered. This is the Tx parallel to l3mdev_ip{6}_rcv in the receive path and is the basis for removing the existing hook that returns the vrf dst on the fib lookup. Signed-off-by: David Ahern <dsa@cumulusnetworks.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-08-30net: lwtunnel: Handle fragmentationRoopa Prabhu
Today mpls iptunnel lwtunnel_output redirect expects the tunnel output function to handle fragmentation. This is ok but can be avoided if we did not do the mpls output redirect too early. ie we could wait until ip fragmentation is done and then call mpls output for each ip fragment. To make this work we will need, 1) the lwtunnel state to carry encap headroom 2) and do the redirect to the encap output handler on the ip fragment (essentially do the output redirect after fragmentation) This patch adds tunnel headroom in lwtstate to make sure we account for tunnel data in mtu calculations during fragmentation and adds new xmit redirect handler to redirect to lwtunnel xmit func after ip fragmentation. This includes IPV6 and some mtu fixes and testing from David Ahern. Signed-off-by: Roopa Prabhu <roopa@cumulusnetworks.com> Signed-off-by: David Ahern <dsa@cumulusnetworks.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-06-17net: vrf: Implement get_saddr for IPv6David Ahern
IPv6 source address selection needs to consider the real egress route. Similar to IPv4 implement a get_saddr6 method which is called if source address has not been set. The get_saddr6 method does a full lookup which means pulling a route from the VRF FIB table and properly considering linklocal/multicast destination addresses. Lookup failures (eg., unreachable) then cause the source address selection to fail which gets propagated back to the caller. Signed-off-by: David Ahern <dsa@cumulusnetworks.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-06-10Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller
Conflicts: net/sched/act_police.c net/sched/sch_drr.c net/sched/sch_hfsc.c net/sched/sch_prio.c net/sched/sch_red.c net/sched/sch_tbf.c In net-next the drop methods of the packet schedulers got removed, so the bug fixes to them in 'net' are irrelevant. A packet action unload crash fix conflicts with the addition of the new firstuse timestamp. Signed-off-by: David S. Miller <davem@davemloft.net>
2016-06-08ipv6: Skip XFRM lookup if dst_entry in socket cache is validJakub Sitnicki
At present we perform an xfrm_lookup() for each UDPv6 message we send. The lookup involves querying the flow cache (flow_cache_lookup) and, in case of a cache miss, creating an XFRM bundle. If we miss the flow cache, we can end up creating a new bundle and deriving the path MTU (xfrm_init_pmtu) from on an already transformed dst_entry, which we pass from the socket cache (sk->sk_dst_cache) down to xfrm_lookup(). This can happen only if we're caching the dst_entry in the socket, that is when we're using a connected UDP socket. To put it another way, the path MTU shrinks each time we miss the flow cache, which later on leads to incorrectly fragmented payload. It can be observed with ESPv6 in transport mode: 1) Set up a transformation and lower the MTU to trigger fragmentation # ip xfrm policy add dir out src ::1 dst ::1 \ tmpl src ::1 dst ::1 proto esp spi 1 # ip xfrm state add src ::1 dst ::1 \ proto esp spi 1 enc 'aes' 0x0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b # ip link set dev lo mtu 1500 2) Monitor the packet flow and set up an UDP sink # tcpdump -ni lo -ttt & # socat udp6-listen:12345,fork /dev/null & 3) Send a datagram that needs fragmentation with a connected socket # perl -e 'print "@" x 1470 | socat - udp6:[::1]:12345 2016/06/07 18:52:52 socat[724] E read(3, 0x555bb3d5ba00, 8192): Protocol error 00:00:00.000000 IP6 ::1 > ::1: frag (0|1448) ESP(spi=0x00000001,seq=0x2), length 1448 00:00:00.000014 IP6 ::1 > ::1: frag (1448|32) 00:00:00.000050 IP6 ::1 > ::1: ESP(spi=0x00000001,seq=0x3), length 1272 (^ ICMPv6 Parameter Problem) 00:00:00.000022 IP6 ::1 > ::1: ESP(spi=0x00000001,seq=0x5), length 136 4) Compare it to a non-connected socket # perl -e 'print "@" x 1500' | socat - udp6-sendto:[::1]:12345 00:00:40.535488 IP6 ::1 > ::1: frag (0|1448) ESP(spi=0x00000001,seq=0x6), length 1448 00:00:00.000010 IP6 ::1 > ::1: frag (1448|64) What happens in step (3) is: 1) when connecting the socket in __ip6_datagram_connect(), we perform an XFRM lookup, miss the flow cache, create an XFRM bundle, and cache the destination, 2) afterwards, when sending the datagram, we perform an XFRM lookup, again, miss the flow cache (due to mismatch of flowi6_iif and flowi6_oif, which is an issue of its own), and recreate an XFRM bundle based on the cached (and already transformed) destination. To prevent the recreation of an XFRM bundle, avoid an XFRM lookup altogether whenever we already have a destination entry cached in the socket. This prevents the path MTU shrinkage and brings us on par with UDPv4. The fix also benefits connected PINGv6 sockets, another user of ip6_sk_dst_lookup_flow(), who also suffer messages being transformed twice. Joint work with Hannes Frederic Sowa. Reported-by: Jan Tluka <jtluka@redhat.com> Signed-off-by: Jakub Sitnicki <jkbs@redhat.com> Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-06-03skbuff: introduce skb_gso_validate_mtuMarcelo Ricardo Leitner
skb_gso_network_seglen is not enough for checking fragment sizes if skb is using GSO_BY_FRAGS as we have to check frag per frag. This patch introduces skb_gso_validate_mtu, based on the former, which will wrap the use case inside it as all calls to skb_gso_network_seglen were to validate if it fits on a given TMU, and improve the check. Signed-off-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Tested-by: Xin Long <lucien.xin@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-05-03ipv6: add new struct ipcm6_cookieWei Wang
In the sendmsg function of UDP, raw, ICMP and l2tp sockets, we use local variables like hlimits, tclass, opt and dontfrag and pass them to corresponding functions like ip6_make_skb, ip6_append_data and xxx_push_pending_frames. This is not a good practice and makes it hard to add new parameters. This fix introduces a new struct ipcm6_cookie similar to ipcm_cookie in ipv4 and include the above mentioned variables. And we only pass the pointer to this structure to corresponding functions. This makes it easier to add new parameters in the future and makes the function cleaner. Signed-off-by: Wei Wang <weiwan@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-04-27ipv6: rename IP6_INC_STATS_BH()Eric Dumazet
Rename IP6_INC_STATS_BH() to __IP6_INC_STATS() and IP6_ADD_STATS_BH() to __IP6_ADD_STATS() Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-04-09Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller
2016-04-07ipv6: Count in extension headers in skb->network_headerJakub Sitnicki
When sending a UDPv6 message longer than MTU, account for the length of fragmentable IPv6 extension headers in skb->network_header offset. Same as we do in alloc_new_skb path in __ip6_append_data(). This ensures that later on __ip6_make_skb() will make space in headroom for fragmentable extension headers: /* move skb->data to ip header from ext header */ if (skb->data < skb_network_header(skb)) __skb_pull(skb, skb_network_offset(skb)); Prevents a splat due to skb_under_panic: skbuff: skb_under_panic: text:ffffffff8143397b len:2126 put:14 \ head:ffff880005bacf50 data:ffff880005bacf4a tail:0x48 end:0xc0 dev:lo ------------[ cut here ]------------ kernel BUG at net/core/skbuff.c:104! invalid opcode: 0000 [#1] KASAN CPU: 0 PID: 160 Comm: reproducer Not tainted 4.6.0-rc2 #65 [...] Call Trace: [<ffffffff813eb7b9>] skb_push+0x79/0x80 [<ffffffff8143397b>] eth_header+0x2b/0x100 [<ffffffff8141e0d0>] neigh_resolve_output+0x210/0x310 [<ffffffff814eab77>] ip6_finish_output2+0x4a7/0x7c0 [<ffffffff814efe3a>] ip6_output+0x16a/0x280 [<ffffffff815440c1>] ip6_local_out+0xb1/0xf0 [<ffffffff814f1115>] ip6_send_skb+0x45/0xd0 [<ffffffff81518836>] udp_v6_send_skb+0x246/0x5d0 [<ffffffff8151985e>] udpv6_sendmsg+0xa6e/0x1090 [...] Reported-by: Ji Jianwen <jiji@redhat.com> Signed-off-by: Jakub Sitnicki <jkbs@redhat.com> Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-04-04sock: enable timestamping using control messagesSoheil Hassas Yeganeh
Currently, SOL_TIMESTAMPING can only be enabled using setsockopt. This is very costly when users want to sample writes to gather tx timestamps. Add support for enabling SO_TIMESTAMPING via control messages by using tsflags added in `struct sockcm_cookie` (added in the previous patches in this series) to set the tx_flags of the last skb created in a sendmsg. With this patch, the timestamp recording bits in tx_flags of the skbuff is overridden if SO_TIMESTAMPING is passed in a cmsg. Please note that this is only effective for overriding the recording timestamps flags. Users should enable timestamp reporting (e.g., SOF_TIMESTAMPING_SOFTWARE | SOF_TIMESTAMPING_OPT_ID) using socket options and then should ask for SOF_TIMESTAMPING_TX_* using control messages per sendmsg to sample timestamps for each write. Signed-off-by: Soheil Hassas Yeganeh <soheil@google.com> Acked-by: Willem de Bruijn <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-03-01net: remove skb_sender_cpu_clear()WANG Cong
After commit 52bd2d62ce67 ("net: better skb->sender_cpu and skb->napi_id cohabitation") skb_sender_cpu_clear() becomes empty and can be removed. Cc: Eric Dumazet <edumazet@google.com> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-01-29ipv6: enforce flowi6_oif usage in ip6_dst_lookup_tail()Paolo Abeni
The current implementation of ip6_dst_lookup_tail basically ignore the egress ifindex match: if the saddr is set, ip6_route_output() purposefully ignores flowi6_oif, due to the commit d46a9d678e4c ("net: ipv6: Dont add RT6_LOOKUP_F_IFACE flag if saddr set"), if the saddr is 'any' the first route lookup in ip6_dst_lookup_tail fails, but upon failure a second lookup will be performed with saddr set, thus ignoring the ifindex constraint. This commit adds an output route lookup function variant, which allows the caller to specify lookup flags, and modify ip6_dst_lookup_tail() to enforce the ifindex match on the second lookup via said helper. ip6_route_output() becames now a static inline function build on top of ip6_route_output_flags(); as a side effect, out-of-tree modules need now a GPL license to access the output route lookup functionality. Signed-off-by: Paolo Abeni <pabeni@redhat.com> Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Acked-by: David Ahern <dsa@cumulusnetworks.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-01-11Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller
Conflicts: drivers/net/bonding/bond_main.c drivers/net/ethernet/mellanox/mlxsw/spectrum.h drivers/net/ethernet/mellanox/mlxsw/spectrum_switchdev.c The bond_main.c and mellanox switch conflicts were cases of overlapping changes. Signed-off-by: David S. Miller <davem@davemloft.net>
2016-01-11udp: disallow UFO for sockets with SO_NO_CHECK optionMichal Kubeček
Commit acf8dd0a9d0b ("udp: only allow UFO for packets from SOCK_DGRAM sockets") disallows UFO for packets sent from raw sockets. We need to do the same also for SOCK_DGRAM sockets with SO_NO_CHECK options, even if for a bit different reason: while such socket would override the CHECKSUM_PARTIAL set by ip_ufo_append_data(), gso_size is still set and bad offloading flags warning is triggered in __skb_gso_segment(). In the IPv6 case, SO_NO_CHECK option is ignored but we need to disallow UFO for packets sent by sockets with UDP_NO_CHECK6_TX option. Signed-off-by: Michal Kubecek <mkubecek@suse.cz> Tested-by: Shannon Nelson <shannon.nelson@intel.com> Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-12-15net: Eliminate NETIF_F_GEN_CSUM and NETIF_F_V[46]_CSUMTom Herbert
These netif flags are unnecessary convolutions. It is more straightforward to just use NETIF_F_HW_CSUM, NETIF_F_IP_CSUM, and NETIF_F_IPV6_CSUM directly. This patch also: - Cleans up can_checksum_protocol - Simplifies netdev_intersect_features Signed-off-by: Tom Herbert <tom@herbertland.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-11-01ipv6: add defensive check for CHECKSUM_PARTIAL skbs in ip_fragmentHannes Frederic Sowa
CHECKSUM_PARTIAL skbs should never arrive in ip_fragment. If we get one of those warn about them once and handle them gracefully by recalculating the checksum. Fixes: commit 32dce968dd987 ("ipv6: Allow for partial checksums on non-ufo packets") See-also: commit 72e843bb09d45 ("ipv6: ip6_fragment() should check CHECKSUM_PARTIAL") Cc: Eric Dumazet <edumazet@google.com> Cc: Vlad Yasevich <vyasevich@gmail.com> Cc: Benjamin Coddington <bcodding@redhat.com> Cc: Tom Herbert <tom@herbertland.com> Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-11-01ipv6: no CHECKSUM_PARTIAL on MSG_MORE corked socketsHannes Frederic Sowa
We cannot reliable calculate packet size on MSG_MORE corked sockets and thus cannot decide if they are going to be fragmented later on, so better not use CHECKSUM_PARTIAL in the first place. The IPv6 code also intended to protect and not use CHECKSUM_PARTIAL in the existence of IPv6 extension headers, but the condition was wrong. Fix it up, too. Also the condition to check whether the packet fits into one fragment was wrong and has been corrected. Fixes: commit 32dce968dd987 ("ipv6: Allow for partial checksums on non-ufo packets") See-also: commit 72e843bb09d45 ("ipv6: ip6_fragment() should check CHECKSUM_PARTIAL") Cc: Eric Dumazet <edumazet@google.com> Cc: Vlad Yasevich <vyasevich@gmail.com> Cc: Benjamin Coddington <bcodding@redhat.com> Cc: Tom Herbert <tom@herbertland.com> Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-11-01Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller
2015-10-29ipv6: protect mtu calculation of wrap-around and infinite loop by rounding ↵Hannes Frederic Sowa
issues Raw sockets with hdrincl enabled can insert ipv6 extension headers right into the data stream. In case we need to fragment those packets, we reparse the options header to find the place where we can insert the fragment header. If the extension headers exceed the link's MTU we actually cannot make progress in such a case. Instead of ending up in broken arithmetic or rounding towards 0 and entering an endless loop in ip6_fragment, just prevent those cases by aborting early and signal -EMSGSIZE to user space. This is the second version of the patch which doesn't use the overflow_usub function, which got reverted for now. Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Reported-by: Dmitry Vyukov <dvyukov@google.com> Cc: Dmitry Vyukov <dvyukov@google.com> Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-29Revert "Merge branch 'ipv6-overflow-arith'"Hannes Frederic Sowa
Linus dislikes these changes. To not hold up the net-merge let's revert it for now and fix the bug like Linus suggested. This reverts commit ec3661b42257d9a06cf0d318175623ac7a660113, reversing changes made to c80dbe04612986fd6104b4a1be21681b113b5ac9. Cc: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-24Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller
Conflicts: net/ipv6/xfrm6_output.c net/openvswitch/flow_netlink.c net/openvswitch/vport-gre.c net/openvswitch/vport-vxlan.c net/openvswitch/vport.c net/openvswitch/vport.h The openvswitch conflicts were overlapping changes. One was the egress tunnel info fix in 'net' and the other was the vport ->send() op simplification in 'net-next'. The xfrm6_output.c conflicts was also a simplification overlapping a bug fix. Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-23ipv6: protect mtu calculation of wrap-around and infinite loop by rounding ↵Hannes Frederic Sowa
issues Raw sockets with hdrincl enabled can insert ipv6 extension headers right into the data stream. In case we need to fragment those packets, we reparse the options header to find the place where we can insert the fragment header. If the extension headers exceed the link's MTU we actually cannot make progress in such a case. Instead of ending up in broken arithmetic or rounding towards 0 and entering an endless loop in ip6_fragment, just prevent those cases by aborting early and signal -EMSGSIZE to user space. Reported-by: Dmitry Vyukov <dvyukov@google.com> Cc: Dmitry Vyukov <dvyukov@google.com> Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-21net: Really fix vti6 with oif in dst lookupsDavid Ahern
6e28b000825d ("net: Fix vti use case with oif in dst lookups for IPv6") is missing the checks on FLOWI_FLAG_SKIP_NH_OIF. Add them. Fixes: 42a7b32b73d6 ("xfrm: Add oif to dst lookups") Cc: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: David Ahern <dsa@cumulusnetworks.com> Acked-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: David S. Miller <davem@davemloft.net>