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2017-05-02net/packet: fix overflow in check for tp_reserveAndrey Konovalov
[ Upstream commit bcc5364bdcfe131e6379363f089e7b4108d35b70 ] When calculating po->tp_hdrlen + po->tp_reserve the result can overflow. Fix by checking that tp_reserve <= INT_MAX on assign. Signed-off-by: Andrey Konovalov <andreyknvl@google.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>
2017-05-02net/packet: fix overflow in check for tp_frame_nrAndrey Konovalov
[ Upstream commit 8f8d28e4d6d815a391285e121c3a53a0b6cb9e7b ] When calculating rb->frames_per_block * req->tp_block_nr the result can overflow. Add a check that tp_block_size * tp_block_nr <= UINT_MAX. Since frames_per_block <= tp_block_size, the expression would never overflow. Signed-off-by: Andrey Konovalov <andreyknvl@google.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>
2017-04-18net/packet: fix overflow in check for priv area sizeAndrey Konovalov
commit 2b6867c2ce76c596676bec7d2d525af525fdc6e2 upstream. Subtracting tp_sizeof_priv from tp_block_size and casting to int to check whether one is less then the other doesn't always work (both of them are unsigned ints). Compare them as is instead. Also cast tp_sizeof_priv to u64 before using BLK_PLUS_PRIV, as it can overflow inside BLK_PLUS_PRIV otherwise. Signed-off-by: Andrey Konovalov <andreyknvl@google.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>
2017-03-22net: don't call strlen() on the user buffer in packet_bind_spkt()Alexander Potapenko
[ Upstream commit 540e2894f7905538740aaf122bd8e0548e1c34a4 ] KMSAN (KernelMemorySanitizer, a new error detection tool) reports use of uninitialized memory in packet_bind_spkt(): Acked-by: Eric Dumazet <edumazet@google.com> ================================================================== BUG: KMSAN: use of unitialized memory CPU: 0 PID: 1074 Comm: packet Not tainted 4.8.0-rc6+ #1891 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011 0000000000000000 ffff88006b6dfc08 ffffffff82559ae8 ffff88006b6dfb48 ffffffff818a7c91 ffffffff85b9c870 0000000000000092 ffffffff85b9c550 0000000000000000 0000000000000092 00000000ec400911 0000000000000002 Call Trace: [< inline >] __dump_stack lib/dump_stack.c:15 [<ffffffff82559ae8>] dump_stack+0x238/0x290 lib/dump_stack.c:51 [<ffffffff818a6626>] kmsan_report+0x276/0x2e0 mm/kmsan/kmsan.c:1003 [<ffffffff818a783b>] __msan_warning+0x5b/0xb0 mm/kmsan/kmsan_instr.c:424 [< inline >] strlen lib/string.c:484 [<ffffffff8259b58d>] strlcpy+0x9d/0x200 lib/string.c:144 [<ffffffff84b2eca4>] packet_bind_spkt+0x144/0x230 net/packet/af_packet.c:3132 [<ffffffff84242e4d>] SYSC_bind+0x40d/0x5f0 net/socket.c:1370 [<ffffffff84242a22>] SyS_bind+0x82/0xa0 net/socket.c:1356 [<ffffffff8515991b>] entry_SYSCALL_64_fastpath+0x13/0x8f arch/x86/entry/entry_64.o:? chained origin: 00000000eba00911 [<ffffffff810bb787>] save_stack_trace+0x27/0x50 arch/x86/kernel/stacktrace.c:67 [< inline >] kmsan_save_stack_with_flags mm/kmsan/kmsan.c:322 [< inline >] kmsan_save_stack mm/kmsan/kmsan.c:334 [<ffffffff818a59f8>] kmsan_internal_chain_origin+0x118/0x1e0 mm/kmsan/kmsan.c:527 [<ffffffff818a7773>] __msan_set_alloca_origin4+0xc3/0x130 mm/kmsan/kmsan_instr.c:380 [<ffffffff84242b69>] SYSC_bind+0x129/0x5f0 net/socket.c:1356 [<ffffffff84242a22>] SyS_bind+0x82/0xa0 net/socket.c:1356 [<ffffffff8515991b>] entry_SYSCALL_64_fastpath+0x13/0x8f arch/x86/entry/entry_64.o:? origin description: ----address@SYSC_bind (origin=00000000eb400911) ================================================================== (the line numbers are relative to 4.8-rc6, but the bug persists upstream) , when I run the following program as root: ===================================== #include <string.h> #include <sys/socket.h> #include <netpacket/packet.h> #include <net/ethernet.h> int main() { struct sockaddr addr; memset(&addr, 0xff, sizeof(addr)); addr.sa_family = AF_PACKET; int fd = socket(PF_PACKET, SOCK_PACKET, htons(ETH_P_ALL)); bind(fd, &addr, sizeof(addr)); return 0; } ===================================== This happens because addr.sa_data copied from the userspace is not zero-terminated, and copying it with strlcpy() in packet_bind_spkt() results in calling strlen() on the kernel copy of that non-terminated buffer. 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>
2017-02-26packet: Do not call fanout_release from atomic contextsAnoob Soman
[ Upstream commit 2bd624b4611ffee36422782d16e1c944d1351e98 ] Commit 6664498280cf ("packet: call fanout_release, while UNREGISTERING a netdev"), unfortunately, introduced the following issues. 1. calling mutex_lock(&fanout_mutex) (fanout_release()) from inside rcu_read-side critical section. rcu_read_lock disables preemption, most often, which prohibits calling sleeping functions. [ ] include/linux/rcupdate.h:560 Illegal context switch in RCU read-side critical section! [ ] [ ] rcu_scheduler_active = 1, debug_locks = 0 [ ] 4 locks held by ovs-vswitchd/1969: [ ] #0: (cb_lock){++++++}, at: [<ffffffff8158a6c9>] genl_rcv+0x19/0x40 [ ] #1: (ovs_mutex){+.+.+.}, at: [<ffffffffa04878ca>] ovs_vport_cmd_del+0x4a/0x100 [openvswitch] [ ] #2: (rtnl_mutex){+.+.+.}, at: [<ffffffff81564157>] rtnl_lock+0x17/0x20 [ ] #3: (rcu_read_lock){......}, at: [<ffffffff81614165>] packet_notifier+0x5/0x3f0 [ ] [ ] Call Trace: [ ] [<ffffffff813770c1>] dump_stack+0x85/0xc4 [ ] [<ffffffff810c9077>] lockdep_rcu_suspicious+0x107/0x110 [ ] [<ffffffff810a2da7>] ___might_sleep+0x57/0x210 [ ] [<ffffffff810a2fd0>] __might_sleep+0x70/0x90 [ ] [<ffffffff8162e80c>] mutex_lock_nested+0x3c/0x3a0 [ ] [<ffffffff810de93f>] ? vprintk_default+0x1f/0x30 [ ] [<ffffffff81186e88>] ? printk+0x4d/0x4f [ ] [<ffffffff816106dd>] fanout_release+0x1d/0xe0 [ ] [<ffffffff81614459>] packet_notifier+0x2f9/0x3f0 2. calling mutex_lock(&fanout_mutex) inside spin_lock(&po->bind_lock). "sleeping function called from invalid context" [ ] BUG: sleeping function called from invalid context at kernel/locking/mutex.c:620 [ ] in_atomic(): 1, irqs_disabled(): 0, pid: 1969, name: ovs-vswitchd [ ] INFO: lockdep is turned off. [ ] Call Trace: [ ] [<ffffffff813770c1>] dump_stack+0x85/0xc4 [ ] [<ffffffff810a2f52>] ___might_sleep+0x202/0x210 [ ] [<ffffffff810a2fd0>] __might_sleep+0x70/0x90 [ ] [<ffffffff8162e80c>] mutex_lock_nested+0x3c/0x3a0 [ ] [<ffffffff816106dd>] fanout_release+0x1d/0xe0 [ ] [<ffffffff81614459>] packet_notifier+0x2f9/0x3f0 3. calling dev_remove_pack(&fanout->prot_hook), from inside spin_lock(&po->bind_lock) or rcu_read-side critical-section. dev_remove_pack() -> synchronize_net(), which might sleep. [ ] BUG: scheduling while atomic: ovs-vswitchd/1969/0x00000002 [ ] INFO: lockdep is turned off. [ ] Call Trace: [ ] [<ffffffff813770c1>] dump_stack+0x85/0xc4 [ ] [<ffffffff81186274>] __schedule_bug+0x64/0x73 [ ] [<ffffffff8162b8cb>] __schedule+0x6b/0xd10 [ ] [<ffffffff8162c5db>] schedule+0x6b/0x80 [ ] [<ffffffff81630b1d>] schedule_timeout+0x38d/0x410 [ ] [<ffffffff810ea3fd>] synchronize_sched_expedited+0x53d/0x810 [ ] [<ffffffff810ea6de>] synchronize_rcu_expedited+0xe/0x10 [ ] [<ffffffff8154eab5>] synchronize_net+0x35/0x50 [ ] [<ffffffff8154eae3>] dev_remove_pack+0x13/0x20 [ ] [<ffffffff8161077e>] fanout_release+0xbe/0xe0 [ ] [<ffffffff81614459>] packet_notifier+0x2f9/0x3f0 4. fanout_release() races with calls from different CPU. To fix the above problems, remove the call to fanout_release() under rcu_read_lock(). Instead, call __dev_remove_pack(&fanout->prot_hook) and netdev_run_todo will be happy that &dev->ptype_specific list is empty. In order to achieve this, I moved dev_{add,remove}_pack() out of fanout_{add,release} to __fanout_{link,unlink}. So, call to {,__}unregister_prot_hook() will make sure fanout->prot_hook is removed as well. Fixes: 6664498280cf ("packet: call fanout_release, while UNREGISTERING a netdev") Reported-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Anoob Soman <anoob.soman@citrix.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>
2017-02-26packet: fix races in fanout_add()Eric Dumazet
[ Upstream commit d199fab63c11998a602205f7ee7ff7c05c97164b ] Multiple threads can call fanout_add() at the same time. We need to grab fanout_mutex earlier to avoid races that could lead to one thread freeing po->rollover that was set by another thread. Do the same in fanout_release(), for peace of mind, and to help us finding lockdep issues earlier. Fixes: dc99f600698d ("packet: Add fanout support.") Fixes: 0648ab70afe6 ("packet: rollover prepare: per-socket state") Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Willem de Bruijn <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-02-18packet: round up linear to header lenWillem de Bruijn
[ Upstream commit 57031eb794906eea4e1c7b31dc1e2429c0af0c66 ] Link layer protocols may unconditionally pull headers, as Ethernet does in eth_type_trans. Ensure that the entire link layer header always lies in the skb linear segment. tpacket_snd has such a check. Extend this to packet_snd. Variable length link layer headers complicate the computation somewhat. Here skb->len may be smaller than dev->hard_header_len. Round up the linear length to be at least as long as the smallest of the two. Reported-by: Dmitry Vyukov <dvyukov@google.com> 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> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-12-10packet: fix race condition in packet_set_ringPhilip Pettersson
[ Upstream commit 84ac7260236a49c79eede91617700174c2c19b0c ] When packet_set_ring creates a ring buffer it will initialize a struct timer_list if the packet version is TPACKET_V3. This value can then be raced by a different thread calling setsockopt to set the version to TPACKET_V1 before packet_set_ring has finished. This leads to a use-after-free on a function pointer in the struct timer_list when the socket is closed as the previously initialized timer will not be deleted. The bug is fixed by taking lock_sock(sk) in packet_setsockopt when changing the packet version while also taking the lock at the start of packet_set_ring. Fixes: f6fb8f100b80 ("af-packet: TPACKET_V3 flexible buffer implementation.") Signed-off-by: Philip Pettersson <philip.pettersson@gmail.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>
2016-11-15packet: on direct_xmit, limit tso and csum to supported devicesWillem de Bruijn
[ Upstream commit 104ba78c98808ae837d1f63aae58c183db5505df ] When transmitting on a packet socket with PACKET_VNET_HDR and PACKET_QDISC_BYPASS, validate device support for features requested in vnet_hdr. Drop TSO packets sent to devices that do not support TSO or have the feature disabled. Note that the latter currently do process those packets correctly, regardless of not advertising the feature. Because of SKB_GSO_DODGY, it is not sufficient to test device features with netif_needs_gso. Full validate_xmit_skb is needed. Switch to software checksum for non-TSO packets that request checksum offload if that device feature is unsupported or disabled. Note that similar to the TSO case, device drivers may perform checksum offload correctly even when not advertising it. When switching to software checksum, packets hit skb_checksum_help, which has two BUG_ON checksum not in linear segment. Packet sockets always allocate at least up to csum_start + csum_off + 2 as linear. Tested by running github.com/wdebruij/kerneltools/psock_txring_vnet.c ethtool -K eth0 tso off tx on psock_txring_vnet -d $dst -s $src -i eth0 -l 2000 -n 1 -q -v psock_txring_vnet -d $dst -s $src -i eth0 -l 2000 -n 1 -q -v -N ethtool -K eth0 tx off psock_txring_vnet -d $dst -s $src -i eth0 -l 1000 -n 1 -q -v -G psock_txring_vnet -d $dst -s $src -i eth0 -l 1000 -n 1 -q -v -G -N v2: - add EXPORT_SYMBOL_GPL(validate_xmit_skb_list) Fixes: d346a3fae3ff ("packet: introduce PACKET_QDISC_BYPASS socket option") Signed-off-by: Willem de Bruijn <willemb@google.com> Acked-by: Eric Dumazet <edumazet@google.com> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-11-15packet: call fanout_release, while UNREGISTERING a netdevAnoob Soman
[ Upstream commit 6664498280cf17a59c3e7cf1a931444c02633ed1 ] If a socket has FANOUT sockopt set, a new proto_hook is registered as part of fanout_add(). When processing a NETDEV_UNREGISTER event in af_packet, __fanout_unlink is called for all sockets, but prot_hook which was registered as part of fanout_add is not removed. Call fanout_release, on a NETDEV_UNREGISTER, which removes prot_hook and removes fanout from the fanout_list. This fixes BUG_ON(!list_empty(&dev->ptype_specific)) in netdev_run_todo() Signed-off-by: Anoob Soman <anoob.soman@citrix.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-07-27packet: Use symmetric hash for PACKET_FANOUT_HASH.David S. Miller
[ Upstream commit eb70db8756717b90c01ccc765fdefc4dd969fc74 ] People who use PACKET_FANOUT_HASH want a symmetric hash, meaning that they want packets going in both directions on a flow to hash to the same bucket. The core kernel SKB hash became non-symmetric when the ipv6 flow label and other entities were incorporated into the standard flow hash order to increase entropy. But there are no users of PACKET_FANOUT_HASH who want an assymetric hash, they all want a symmetric one. Therefore, use the flow dissector to compute a flat symmetric hash over only the protocol, addresses and ports. This hash does not get installed into and override the normal skb hash, so this change has no effect whatsoever on the rest of the stack. Reported-by: Eric Leblond <eric@regit.org> Tested-by: Eric Leblond <eric@regit.org> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-05-18packet: fix heap info leak in PACKET_DIAG_MCLIST sock_diag interfaceMathias Krause
[ Upstream commit 309cf37fe2a781279b7675d4bb7173198e532867 ] Because we miss to wipe the remainder of i->addr[] in packet_mc_add(), pdiag_put_mclist() leaks uninitialized heap bytes via the PACKET_DIAG_MCLIST netlink attribute. Fix this by explicitly memset(0)ing the remaining bytes in i->addr[]. Fixes: eea68e2f1a00 ("packet: Report socket mclist info via diag module") Signed-off-by: Mathias Krause <minipli@googlemail.com> Cc: Eric W. Biederman <ebiederm@xmission.com> Cc: Pavel Emelyanov <xemul@parallels.com> Acked-by: Pavel Emelyanov <xemul@virtuozzo.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-04-20packet: validate variable length ll headersWillem de Bruijn
[ Upstream commit 9ed988cd591500c040b2a6257bc68543e08ceeef ] Replace link layer header validation check ll_header_truncate with more generic dev_validate_header. Validation based on hard_header_len incorrectly drops valid packets in variable length protocols, such as AX25. dev_validate_header calls header_ops.validate for such protocols to ensure correctness below hard_header_len. See also http://comments.gmane.org/gmane.linux.network/401064 Fixes 9c7077622dd9 ("packet: make packet_snd fail on len smaller than l2 header") 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>
2015-11-29packet: Allow packets with only a header (but no payload)Martin Blumenstingl
Commit 9c7077622dd91 ("packet: make packet_snd fail on len smaller than l2 header") added validation for the packet size in packet_snd. This change enforces that every packet needs a header (with at least hard_header_len bytes) plus a payload with at least one byte. Before this change the payload was optional. This fixes PPPoE connections which do not have a "Service" or "Host-Uniq" configured (which is violating the spec, but is still widely used in real-world setups). Those are currently failing with the following message: "pppd: packet size is too short (24 <= 24)" Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-11-17packet: Use PAGE_ALIGNED macroTobias Klauser
Use PAGE_ALIGNED(...) instead of open-coding it. Signed-off-by: Tobias Klauser <tklauser@distanz.ch> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-11-17packet: Don't check frames_per_block against negative valuesTobias Klauser
rb->frames_per_block is an unsigned int, thus can never be negative. Also fix spacing in the calculation of frames_per_block. Signed-off-by: Tobias Klauser <tklauser@distanz.ch> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-11-15packet: fix tpacket_snd max frame lenDaniel Borkmann
Since it's introduction in commit 69e3c75f4d54 ("net: TX_RING and packet mmap"), TX_RING could be used from SOCK_DGRAM and SOCK_RAW side. When used with SOCK_DGRAM only, the size_max > dev->mtu + reserve check should have reserve as 0, but currently, this is unconditionally set (in it's original form as dev->hard_header_len). I think this is not correct since tpacket_fill_skb() would then take dev->mtu and dev->hard_header_len into account for SOCK_DGRAM, the extra VLAN_HLEN could be possible in both cases. Presumably, the reserve code was copied from packet_snd(), but later on missed the check. Make it similar as we have it in packet_snd(). Fixes: 69e3c75f4d54 ("net: TX_RING and packet mmap") Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Willem de Bruijn <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-11-15packet: infer protocol from ethernet header if unsetDaniel Borkmann
In case no struct sockaddr_ll has been passed to packet socket's sendmsg() when doing a TX_RING flush run, then skb->protocol is set to po->num instead, which is the protocol passed via socket(2)/bind(2). Applications only xmitting can go the path of allocating the socket as socket(PF_PACKET, <mode>, 0) and do a bind(2) on the TX_RING with sll_protocol of 0. That way, register_prot_hook() is neither called on creation nor on bind time, which saves cycles when there's no interest in capturing anyway. That leaves us however with po->num 0 instead and therefore the TX_RING flush run sets skb->protocol to 0 as well. Eric reported that this leads to problems when using tools like trafgen over bonding device. I.e. the bonding's hash function could invoke the kernel's flow dissector, which depends on skb->protocol being properly set. In the current situation, all the traffic is then directed to a single slave. Fix it up by inferring skb->protocol from the Ethernet header when not set and we have ARPHRD_ETHER device type. This is only done in case of SOCK_RAW and where we have a dev->hard_header_len length. In case of ARPHRD_ETHER devices, this is guaranteed to cover ETH_HLEN, and therefore being accessed on the skb after the skb_store_bits(). Reported-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Willem de Bruijn <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-11-15packet: only allow extra vlan len on ethernet devicesDaniel Borkmann
Packet sockets can be used by various net devices and are not really restricted to ARPHRD_ETHER device types. However, when currently checking for the extra 4 bytes that can be transmitted in VLAN case, our assumption is that we generally probe on ARPHRD_ETHER devices. Therefore, before looking into Ethernet header, check the device type first. This also fixes the issue where non-ARPHRD_ETHER devices could have no dev->hard_header_len in TX_RING SOCK_RAW case, and thus the check would test unfilled linear part of the skb (instead of non-linear). Fixes: 57f89bfa2140 ("network: Allow af_packet to transmit +4 bytes for VLAN packets.") Fixes: 52f1454f629f ("packet: allow to transmit +4 byte in TX_RING slot for VLAN case") Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Willem de Bruijn <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-11-15packet: always probe for transport headerDaniel Borkmann
We concluded that the skb_probe_transport_header() should better be called unconditionally. Avoiding the call into the flow dissector has also not really much to do with the direct xmit mode. While it seems that only virtio_net code makes use of GSO from non RX/TX ring packet socket paths, we should probe for a transport header nevertheless before they hit devices. Reference: http://thread.gmane.org/gmane.linux.network/386173/ Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Jason Wang <jasowang@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-11-15packet: do skb_probe_transport_header when we actually have dataDaniel Borkmann
In tpacket_fill_skb() commit c1aad275b029 ("packet: set transport header before doing xmit") and later on 40893fd0fd4e ("net: switch to use skb_probe_transport_header()") was probing for a transport header on the skb from a ring buffer slot, but at a time, where the skb has _not even_ been filled with data yet. So that call into the flow dissector is pretty useless. Lets do it after we've set up the skb frags. Fixes: c1aad275b029 ("packet: set transport header before doing xmit") Reported-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Jason Wang <jasowang@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-11-05packet: race condition in packet_bindFrancesco Ruggeri
There is a race conditions between packet_notifier and packet_bind{_spkt}. It happens if packet_notifier(NETDEV_UNREGISTER) executes between the time packet_bind{_spkt} takes a reference on the new netdevice and the time packet_do_bind sets po->ifindex. In this case the notification can be missed. If this happens during a dev_change_net_namespace this can result in the netdevice to be moved to the new namespace while the packet_sock in the old namespace still holds a reference on it. When the netdevice is later deleted in the new namespace the deletion hangs since the packet_sock is not found in the new namespace' &net->packet.sklist. It can be reproduced with the script below. This patch makes packet_do_bind check again for the presence of the netdevice in the packet_sock's namespace after the synchronize_net in unregister_prot_hook. More in general it also uses the rcu lock for the duration of the bind to stop dev_change_net_namespace/rollback_registered_many from going past the synchronize_net following unlist_netdevice, so that no NETDEV_UNREGISTER notifications can happen on the new netdevice while the bind is executing. In order to do this some code from packet_bind{_spkt} is consolidated into packet_do_dev. import socket, os, time, sys proto=7 realDev='em1' vlanId=400 if len(sys.argv) > 1: vlanId=int(sys.argv[1]) dev='vlan%d' % vlanId os.system('taskset -p 0x10 %d' % os.getpid()) s = socket.socket(socket.PF_PACKET, socket.SOCK_RAW, proto) os.system('ip link add link %s name %s type vlan id %d' % (realDev, dev, vlanId)) os.system('ip netns add dummy') pid=os.fork() if pid == 0: # dev should be moved while packet_do_bind is in synchronize net os.system('taskset -p 0x20000 %d' % os.getpid()) os.system('ip link set %s netns dummy' % dev) os.system('ip netns exec dummy ip link del %s' % dev) s.close() sys.exit(0) time.sleep(.004) try: s.bind(('%s' % dev, proto+1)) except: print 'Could not bind socket' s.close() os.system('ip netns del dummy') sys.exit(0) os.waitpid(pid, 0) s.close() os.system('ip netns del dummy') sys.exit(0) Signed-off-by: Francesco Ruggeri <fruggeri@arista.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-12ipv4: Pass struct net into ip_defrag and ip_check_defragEric W. Biederman
The function ip_defrag is called on both the input and the output paths of the networking stack. In particular conntrack when it is tracking outbound packets from the local machine calls ip_defrag. So add a struct net parameter and stop making ip_defrag guess which network namespace it needs to defragment packets in. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Acked-by: Pablo Neira Ayuso <pablo@netfilter.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-12packet: fix match_fanout_group()Eric Dumazet
Recent TCP listener patches exposed a prior af_packet bug : match_fanout_group() blindly assumes it is always safe to cast sk to a packet socket to compare fanout with af_packet_priv But SYNACK packets can be sent while attached to request_sock, which are smaller than a "struct sock". We can read non existent memory and crash. Fixes: c0de08d04215 ("af_packet: don't emit packet on orig fanout group") Fixes: ca6fb0651883 ("tcp: attach SYNACK messages to request sockets instead of listener") Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Willem de Bruijn <willemb@google.com> Cc: Eric Leblond <eric@regit.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-12packet: support per-packet fwmark for af_packet sendmsgEdward Jee
Signed-off-by: Edward Hyunkoo Jee <edjee@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Willem de Bruijn <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-11bpf: fix cb access in socket filter programsAlexei Starovoitov
eBPF socket filter programs may see junk in 'u32 cb[5]' area, since it could have been used by protocol layers earlier. For socket filter programs used in af_packet we need to clean 20 bytes of skb->cb area if it could be used by the program. For programs attached to TCP/UDP sockets we need to save/restore these 20 bytes, since it's used by protocol layers. Remove SK_RUN_FILTER macro, since it's no longer used. Long term we may move this bpf cb area to per-cpu scratch, but that requires addition of new 'per-cpu load/store' instructions, so not suitable as a short term fix. Fixes: d691f9e8d440 ("bpf: allow programs to write to certain skb fields") Reported-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Alexei Starovoitov <ast@plumgrid.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-05bpf, seccomp: prepare for upcoming criu supportDaniel Borkmann
The current ongoing effort to dump existing cBPF seccomp filters back to user space requires to hold the pre-transformed instructions like we do in case of socket filters from sk_attach_filter() side, so they can be reloaded in original form at a later point in time by utilities such as criu. To prepare for this, simply extend the bpf_prog_create_from_user() API to hold a flag that tells whether we should store the original or not. Also, fanout filters could make use of that in future for things like diag. While fanout filters already use bpf_prog_destroy(), move seccomp over to them as well to handle original programs when present. Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Cc: Tycho Andersen <tycho.andersen@canonical.com> Cc: Pavel Emelyanov <xemul@parallels.com> Cc: Kees Cook <keescook@chromium.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Alexei Starovoitov <ast@plumgrid.com> Tested-by: Tycho Andersen <tycho.andersen@canonical.com> Acked-by: Alexei Starovoitov <ast@plumgrid.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-23Fix AF_PACKET ABI breakage in 4.2David Woodhouse
Commit 7d82410950aa ("virtio: add explicit big-endian support to memory accessors") accidentally changed the virtio_net header used by AF_PACKET with PACKET_VNET_HDR from host-endian to big-endian. Since virtio_legacy_is_little_endian() is a very long identifier, define a vio_le macro and use that throughout the code instead of the hard-coded 'false' for little-endian. This restores the ABI to match 4.1 and earlier kernels, and makes my test program work again. Signed-off-by: David Woodhouse <David.Woodhouse@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-08-17packet: add extended BPF fanout modeWillem de Bruijn
Add fanout mode PACKET_FANOUT_EBPF that accepts an en extended BPF program to select a socket. Update the internal eBPF program by passing to socket option SOL_PACKET/PACKET_FANOUT_DATA a file descriptor returned by bpf(). Signed-off-by: Willem de Bruijn <willemb@google.com> Acked-by: Alexei Starovoitov <ast@plumgrid.com> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-08-17packet: add classic BPF fanout modeWillem de Bruijn
Add fanout mode PACKET_FANOUT_CBPF that accepts a classic BPF program to select a socket. This avoids having to keep adding special case fanout modes. One example use case is application layer load balancing. The QUIC protocol, for instance, encodes a connection ID in UDP payload. Also add socket option SOL_PACKET/PACKET_FANOUT_DATA that updates data associated with the socket group. Fanout mode PACKET_FANOUT_CBPF is the only user so far. Signed-off-by: Willem de Bruijn <willemb@google.com> Acked-by: Alexei Starovoitov <ast@plumgrid.com> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-31Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller
Conflicts: arch/s390/net/bpf_jit_comp.c drivers/net/ethernet/ti/netcp_ethss.c net/bridge/br_multicast.c net/ipv4/ip_fragment.c All four conflicts were cases of simple overlapping changes. Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-29packet: remove handling of tx_ring from prb_shutdown_retire_blk_timer()Tobias Klauser
Follow e8e85cc5eb57 ("packet: remove handling of tx_ring") and remove the tx_ring parameter from prb_shutdown_retire_blk_timer() as it is only called with tx_ring = 0. Signed-off-by: Tobias Klauser <tklauser@distanz.ch> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-29packet: tpacket_snd(): fix signed/unsigned comparisonAlexander Drozdov
tpacket_fill_skb() can return a negative value (-errno) which is stored in tp_len variable. In that case the following condition will be (but shouldn't be) true: tp_len > dev->mtu + dev->hard_header_len as dev->mtu and dev->hard_header_len are both unsigned. That may lead to just returning an incorrect EMSGSIZE errno to the user. Fixes: 52f1454f629fa ("packet: allow to transmit +4 byte in TX_RING slot for VLAN case") Signed-off-by: Alexander Drozdov <al.drozdov@gmail.com> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-27packet: missing dev_put() in packet_do_bind()Lars Westerhoff
When binding a PF_PACKET socket, the use count of the bound interface is always increased with dev_hold in dev_get_by_{index,name}. However, when rebound with the same protocol and device as in the previous bind the use count of the interface was not decreased. Ultimately, this caused the deletion of the interface to fail with the following message: unregister_netdevice: waiting for dummy0 to become free. Usage count = 1 This patch moves the dev_put out of the conditional part that was only executed when either the protocol or device changed on a bind. Fixes: 902fefb82ef7 ('packet: improve socket create/bind latency in some cases') Signed-off-by: Lars Westerhoff <lars.westerhoff@newtec.eu> Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Reviewed-by: Daniel Borkmann <dborkman@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-06-24Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller
Conflicts: drivers/net/ethernet/mellanox/mlx4/main.c net/packet/af_packet.c Both conflicts were cases of simple overlapping changes. Signed-off-by: David S. Miller <davem@davemloft.net>
2015-06-23packet: remove handling of tx_ringManinder Singh
Remove handling of tx_ring in prb_setup_retire_blk_timer for TPACKET_V3 because init_prb_bdqc is called only for zero tx_ring and thus prb_setup_retire_blk_timer for zero tx_ring only. And also in functon init_prb_bdqc there is no usage of tx_ring. Thus removing tx_ring from init_prb_bdqc. Signed-off-by: Maninder Singh <maninder1.s@samsung.com> Suggested-by: Frans Klaver <fransklaver@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-06-21packet: avoid out of bounds read in round robin fanoutWillem de Bruijn
PACKET_FANOUT_LB computes f->rr_cur such that it is modulo f->num_members. It returns the old value unconditionally, but f->num_members may have changed since the last store. Ensure that the return value is always < num. When modifying the logic, simplify it further by replacing the loop with an unconditional atomic increment. Fixes: dc99f600698d ("packet: Add fanout support.") Suggested-by: Eric Dumazet <edumazet@google.com> 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>
2015-06-21packet: free packet_rollover after synchronize_netWillem de Bruijn
Destruction of the po->rollover must be delayed until there are no more packets in flight that can access it. The field is destroyed in packet_release, before synchronize_net. Delay using rcu. Fixes: 0648ab70afe6 ("packet: rollover prepare: per-socket state") Suggested-by: Eric Dumazet <edumazet@google.com> 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>
2015-06-21packet: read num_members once in packet_rcv_fanout()Eric Dumazet
We need to tell compiler it must not read f->num_members multiple times. Otherwise testing if num is not zero is flaky, and we could attempt an invalid divide by 0 in fanout_demux_cpu() Note bug was present in packet_rcv_fanout_hash() and packet_rcv_fanout_lb() but final 3.1 had a simple location after commit 95ec3eb417115fb ("packet: Add 'cpu' fanout policy.") Fixes: dc99f600698dc ("packet: Add fanout support.") Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Willem de Bruijn <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-17net-packet: fix null pointer exception in rollover modeWillem de Bruijn
Rollover can be enabled as flag or mode. Allocate state in both cases. This solves a NULL pointer exception in fanout_demux_rollover on referencing po->rollover if using mode rollover. Also make sure that in rollover mode each silo is tried (contrary to rollover flag, where the main socket is excluded after an initial try_self). Tested: Passes tools/testing/net/psock_fanout.c, which tests both modes and flag. My previous tests were limited to bench_rollover, which only stresses the flag. The test now completes safely. it still gives an error for mode rollover, because it does not expect the new headroom (ROOM_NORMAL) requirement. I will send a separate patch to the test. Fixes: 0648ab70afe6 ("packet: rollover prepare: per-socket state") Signed-off-by: Willem de Bruijn <willemb@google.com> ---- I should have run this test and caught this before submission, of course. Apologies for the oversight. Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-14packet: fix warnings in rollover lock contentionWillem de Bruijn
Avoid two xchg calls whose return values were unused, causing a warning on some architectures. The relevant variable is a hint and read without mutual exclusion. This fix makes all writers hold the receive_queue lock. Suggested-by: David S. Miller <davem@davemloft.net> Signed-off-by: Willem de Bruijn <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-13packet: rollover statisticsWillem de Bruijn
Rollover indicates exceptional conditions. Export a counter to inform socket owners of this state. If no socket with sufficient room is found, rollover fails. Also count these events. Finally, also count when flows are rolled over early thanks to huge flow detection, to validate its correctness. Tested: Read counters in bench_rollover on all other tests in the patchset Signed-off-by: Willem de Bruijn <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-13packet: rollover huge flows before small flowsWillem de Bruijn
Migrate flows from a socket to another socket in the fanout group not only when the socket is full. Start migrating huge flows early, to divert possible 4-tuple attacks without affecting normal traffic. Introduce fanout_flow_is_huge(). This detects huge flows, which are defined as taking up more than half the load. It does so cheaply, by storing the rxhashes of the N most recent packets. If over half of these are the same rxhash as the current packet, then drop it. This only protects against 4-tuple attacks. N is chosen to fit all data in a single cache line. Tested: Ran bench_rollover for 10 sec with 1.5 Mpps of single flow input. lpbb5:/export/hda3/willemb# ./bench_rollover -l 1000 -r -s cpu rx rx.k drop.k rollover r.huge r.failed 0 14 14 0 0 0 0 1 20 20 0 0 0 0 2 16 16 0 0 0 0 3 6168824 6168824 0 4867721 4867721 0 4 4867741 4867741 0 0 0 0 5 12 12 0 0 0 0 6 15 15 0 0 0 0 7 17 17 0 0 0 0 Signed-off-by: Willem de Bruijn <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-13packet: rollover lock contention avoidanceWillem de Bruijn
Rollover has to call packet_rcv_has_room on sockets in the fanout group to find a socket to migrate to. This operation is expensive especially if the packet sockets use rings, when a lock has to be acquired. Avoid pounding on the lock by all sockets by temporarily marking a socket as "under memory pressure" when such pressure is detected. While set, only the socket owner may call packet_rcv_has_room on the socket. Once it detects normal conditions, it clears the flag. The socket is not used as a victim by any other socket in the meantime. Under reasonably balanced load, each socket writer frequently calls packet_rcv_has_room and clears its own pressure field. As a backup for when the socket is rarely written to, also clear the flag on reading (packet_recvmsg, packet_poll) if this can be done cheaply (i.e., without calling packet_rcv_has_room). This is only for edge cases. Tested: Ran bench_rollover: a process with 8 sockets in a single fanout group, each pinned to a single cpu that receives one nic recv interrupt. RPS and RFS are disabled. The benchmark uses packet rx_ring, which has to take a lock when determining whether a socket has room. Sent 3.5 Mpps of UDP traffic with sufficient entropy to spread uniformly across the packet sockets (and inserted an iptables rule to drop in PREROUTING to avoid protocol stack processing). Without this patch, all sockets try to migrate traffic to neighbors, causing lock contention when searching for a non- empty neighbor. The lock is the top 9 entries. perf record -a -g sleep 5 - 17.82% bench_rollover [kernel.kallsyms] [k] _raw_spin_lock - _raw_spin_lock - 99.00% spin_lock + 81.77% packet_rcv_has_room.isra.41 + 18.23% tpacket_rcv + 0.84% packet_rcv_has_room.isra.41 + 5.20% ksoftirqd/6 [kernel.kallsyms] [k] _raw_spin_lock + 5.15% ksoftirqd/1 [kernel.kallsyms] [k] _raw_spin_lock + 5.14% ksoftirqd/2 [kernel.kallsyms] [k] _raw_spin_lock + 5.12% ksoftirqd/7 [kernel.kallsyms] [k] _raw_spin_lock + 5.12% ksoftirqd/5 [kernel.kallsyms] [k] _raw_spin_lock + 5.10% ksoftirqd/4 [kernel.kallsyms] [k] _raw_spin_lock + 4.66% ksoftirqd/0 [kernel.kallsyms] [k] _raw_spin_lock + 4.45% ksoftirqd/3 [kernel.kallsyms] [k] _raw_spin_lock + 1.55% bench_rollover [kernel.kallsyms] [k] packet_rcv_has_room.isra.41 On net-next with this patch, this lock contention is no longer a top entry. Most time is spent in the actual read function. Next up are other locks: + 15.52% bench_rollover bench_rollover [.] reader + 4.68% swapper [kernel.kallsyms] [k] memcpy_erms + 2.77% swapper [kernel.kallsyms] [k] packet_lookup_frame.isra.51 + 2.56% ksoftirqd/1 [kernel.kallsyms] [k] memcpy_erms + 2.16% swapper [kernel.kallsyms] [k] tpacket_rcv + 1.93% swapper [kernel.kallsyms] [k] mlx4_en_process_rx_cq Looking closer at the remaining _raw_spin_lock, the cost of probing in rollover is now comparable to the cost of taking the lock later in tpacket_rcv. - 1.51% swapper [kernel.kallsyms] [k] _raw_spin_lock - _raw_spin_lock + 33.41% packet_rcv_has_room + 28.15% tpacket_rcv + 19.54% enqueue_to_backlog + 6.45% __free_pages_ok + 2.78% packet_rcv_fanout + 2.13% fanout_demux_rollover + 2.01% netif_receive_skb_internal Signed-off-by: Willem de Bruijn <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-13packet: rollover only to socket with headroomWillem de Bruijn
Only migrate flows to sockets that have sufficient headroom, where sufficient is defined as having at least 25% empty space. The kernel has three different buffer types: a regular socket, a ring with frames (TPACKET_V[12]) or a ring with blocks (TPACKET_V3). The latter two do not expose a read pointer to the kernel, so headroom is not computed easily. All three needs a different implementation to estimate free space. Tested: Ran bench_rollover for 10 sec with 1.5 Mpps of single flow input. bench_rollover has as many sockets as there are NIC receive queues in the system. Each socket is owned by a process that is pinned to one of the receive cpus. RFS is disabled. RPS is enabled with an identity mapping (cpu x -> cpu x), to count drops with softnettop. lpbb5:/export/hda3/willemb# ./bench_rollover -r -l 1000 -s Press [Enter] to exit cpu rx rx.k drop.k rollover r.huge r.failed 0 16 16 0 0 0 0 1 21 21 0 0 0 0 2 5227502 5227502 0 0 0 0 3 18 18 0 0 0 0 4 6083289 6083289 0 5227496 0 0 5 22 22 0 0 0 0 6 21 21 0 0 0 0 7 9 9 0 0 0 0 Signed-off-by: Willem de Bruijn <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-13packet: rollover prepare: per-socket stateWillem de Bruijn
Replace rollover state per fanout group with state per socket. Future patches will add fields to the new structure. Signed-off-by: Willem de Bruijn <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-13packet: rollover prepare: move code out of callsitesWillem de Bruijn
packet_rcv_fanout calls fanout_demux_rollover twice. Move all rollover logic into the callee to simplify these callsites, especially with upcoming changes. The main differences between the two callsites is that the FLAG variant tests whether the socket previously selected by another mode (RR, RND, HASH, ..) has room before migrating flows, whereas the rollover mode has no original socket to test. Signed-off-by: Willem de Bruijn <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-13Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller
Four minor merge conflicts: 1) qca_spi.c renamed the local variable used for the SPI device from spi_device to spi, meanwhile the spi_set_drvdata() call got moved further up in the probe function. 2) Two changes were both adding new members to codel params structure, and thus we had overlapping changes to the initializer function. 3) 'net' was making a fix to sk_release_kernel() which is completely removed in 'net-next'. 4) In net_namespace.c, the rtnl_net_fill() call for GET operations had the command value fixed, meanwhile 'net-next' adjusted the argument signature a bit. This also matches example merge resolutions posted by Stephen Rothwell over the past two days. Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-11net: Pass kern from net_proto_family.create to sk_allocEric W. Biederman
In preparation for changing how struct net is refcounted on kernel sockets pass the knowledge that we are creating a kernel socket from sock_create_kern through to sk_alloc. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-10af_packet / TX_RING not fully non-blocking (w/ MSG_DONTWAIT).Kretschmer, Mathias
This patch fixes an issue where the send(MSG_DONTWAIT) call on a TX_RING is not fully non-blocking in cases where the device's sndBuf is full. We pass nonblock=true to sock_alloc_send_skb() and return any possibly occuring error code (most likely EGAIN) to the caller. As the fast-path stays as it is, we keep the unlikely() around skb == NULL. Signed-off-by: Mathias Kretschmer <mathias.kretschmer@fokus.fraunhofer.de> Signed-off-by: David S. Miller <davem@davemloft.net>