linux/net/core/dev.c, branch v4.9

bpf: Fix bpf_redirect to an ipip/ip6tnl dev

2016-11-13T04:38:07Z

If the bpf program calls bpf_redirect(dev, 0) and dev is an ipip/ip6tnl, it currently includes the mac header. e.g. If dev is ipip, the end result is IP-EthHdr-IP instead of IP-IP. The fix is to pull the mac header. At ingress, skb_postpull_rcsum() is not needed because the ethhdr should have been pulled once already and then got pushed back just before calling the bpf_prog. At egress, this patch calls skb_postpull_rcsum(). If bpf_redirect(dev, BPF_F_INGRESS) is called, it also fails now because it calls dev_forward_skb() which eventually calls eth_type_trans(skb, dev). The eth_type_trans() will set skb->type = PACKET_OTHERHOST because the mac address does not match the redirecting dev->dev_addr. The PACKET_OTHERHOST will eventually cause the ip_rcv() errors out. To fix this, ____dev_forward_skb() is added. Joint work with Daniel Borkmann. Fixes: cfc7381b3002 ("ip_tunnel: add collect_md mode to IPIP tunnel") Fixes: 8d79266bc48c ("ip6_tunnel: add collect_md mode to IPv6 tunnels") Acked-by: Daniel Borkmann Acked-by: Alexei Starovoitov Signed-off-by: Martin KaFai Lau Signed-off-by: David S. Miller

net: mangle zero checksum in skb_checksum_help()

2016-10-31T19:29:11Z

Sending zero checksum is ok for TCP, but not for UDP. UDPv6 receiver should by default drop a frame with a 0 checksum, and UDPv4 would not verify the checksum and might accept a corrupted packet. Simply replace such checksum by 0xffff, regardless of transport. This error was caught on SIT tunnels, but seems generic. Signed-off-by: Eric Dumazet Cc: Maciej Żenczykowski Cc: Willem de Bruijn Acked-by: Maciej Żenczykowski Signed-off-by: David S. Miller

Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net

2016-10-30T03:33:20Z

Pull networking fixes from David Miller: "Lots of fixes, mostly drivers as is usually the case. 1) Don't treat zero DMA address as invalid in vmxnet3, from Alexey Khoroshilov. 2) Fix element timeouts in netfilter's nft_dynset, from Anders K. Pedersen. 3) Don't put aead_req crypto struct on the stack in mac80211, from Ard Biesheuvel. 4) Several uninitialized variable warning fixes from Arnd Bergmann. 5) Fix memory leak in cxgb4, from Colin Ian King. 6) Fix bpf handling of VLAN header push/pop, from Daniel Borkmann. 7) Several VRF semantic fixes from David Ahern. 8) Set skb->protocol properly in ip6_tnl_xmit(), from Eli Cooper. 9) Socket needs to be locked in udp_disconnect(), from Eric Dumazet. 10) Div-by-zero on 32-bit fix in mlx4 driver, from Eugenia Emantayev. 11) Fix stale link state during failover in NCSCI driver, from Gavin Shan. 12) Fix netdev lower adjacency list traversal, from Ido Schimmel. 13) Propvide proper handle when emitting notifications of filter deletes, from Jamal Hadi Salim. 14) Memory leaks and big-endian issues in rtl8xxxu, from Jes Sorensen. 15) Fix DESYNC_FACTOR handling in ipv6, from Jiri Bohac. 16) Several routing offload fixes in mlxsw driver, from Jiri Pirko. 17) Fix broadcast sync problem in TIPC, from Jon Paul Maloy. 18) Validate chunk len before using it in SCTP, from Marcelo Ricardo Leitner. 19) Revert a netns locking change that causes regressions, from Paul Moore. 20) Add recursion limit to GRO handling, from Sabrina Dubroca. 21) GFP_KERNEL in irq context fix in ibmvnic, from Thomas Falcon. 22) Avoid accessing stale vxlan/geneve socket in data path, from Pravin Shelar" * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (189 commits) geneve: avoid using stale geneve socket. vxlan: avoid using stale vxlan socket. qede: Fix out-of-bound fastpath memory access net: phy: dp83848: add dp83822 PHY support enic: fix rq disable tipc: fix broadcast link synchronization problem ibmvnic: Fix missing brackets in init_sub_crq_irqs ibmvnic: Fix releasing of sub-CRQ IRQs in interrupt context Revert "ibmvnic: Fix releasing of sub-CRQ IRQs in interrupt context" arch/powerpc: Update parameters for csum_tcpudp_magic & csum_tcpudp_nofold net/mlx4_en: Save slave ethtool stats command net/mlx4_en: Fix potential deadlock in port statistics flow net/mlx4: Fix firmware command timeout during interrupt test net/mlx4_core: Do not access comm channel if it has not yet been initialized net/mlx4_en: Fix panic during reboot net/mlx4_en: Process all completions in RX rings after port goes up net/mlx4_en: Resolve dividing by zero in 32-bit system net/mlx4_core: Change the default value of enable_qos net/mlx4_core: Avoid setting ports to auto when only one port type is supported net/mlx4_core: Fix the resource-type enum in res tracker to conform to FW spec ...

packet: on direct_xmit, limit tso and csum to supported devices

2016-10-29T19:02:15Z

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 Acked-by: Eric Dumazet Acked-by: Daniel Borkmann Signed-off-by: David S. Miller

net: add recursion limit to GRO

2016-10-20T18:32:22Z

Currently, GRO can do unlimited recursion through the gro_receive handlers. This was fixed for tunneling protocols by limiting tunnel GRO to one level with encap_mark, but both VLAN and TEB still have this problem. Thus, the kernel is vulnerable to a stack overflow, if we receive a packet composed entirely of VLAN headers. This patch adds a recursion counter to the GRO layer to prevent stack overflow. When a gro_receive function hits the recursion limit, GRO is aborted for this skb and it is processed normally. This recursion counter is put in the GRO CB, but could be turned into a percpu counter if we run out of space in the CB. Thanks to Vladimír Beneš for the initial bug report. Fixes: CVE-2016-7039 Fixes: 9b174d88c257 ("net: Add Transparent Ethernet Bridging GRO support.") Fixes: 66e5133f19e9 ("vlan: Add GRO support for non hardware accelerated vlan") Signed-off-by: Sabrina Dubroca Reviewed-by: Jiri Benc Acked-by: Hannes Frederic Sowa Acked-by: Tom Herbert Signed-off-by: David S. Miller

net: core: Correctly iterate over lower adjacency list

2016-10-19T14:38:08Z

Tamir reported the following trace when processing ARP requests received via a vlan device on top of a VLAN-aware bridge: NMI watchdog: BUG: soft lockup - CPU#1 stuck for 22s! [swapper/1:0] [...] CPU: 1 PID: 0 Comm: swapper/1 Tainted: G W 4.8.0-rc7 #1 Hardware name: Mellanox Technologies Ltd. "MSN2100-CB2F"/"SA001017", BIOS 5.6.5 06/07/2016 task: ffff88017edfea40 task.stack: ffff88017ee10000 RIP: 0010:[] [] netdev_all_lower_get_next_rcu+0x33/0x60 [...] Call Trace: [] mlxsw_sp_port_lower_dev_hold+0x5a/0xa0 [mlxsw_spectrum] [] mlxsw_sp_router_netevent_event+0x80/0x150 [mlxsw_spectrum] [] notifier_call_chain+0x4a/0x70 [] atomic_notifier_call_chain+0x1a/0x20 [] call_netevent_notifiers+0x1b/0x20 [] neigh_update+0x306/0x740 [] neigh_event_ns+0x4e/0xb0 [] arp_process+0x66f/0x700 [] ? common_interrupt+0x8c/0x8c [] arp_rcv+0x139/0x1d0 [] ? vlan_do_receive+0xda/0x320 [] __netif_receive_skb_core+0x524/0xab0 [] ? dev_queue_xmit+0x10/0x20 [] ? br_forward_finish+0x3d/0xc0 [bridge] [] ? br_handle_vlan+0xf6/0x1b0 [bridge] [] __netif_receive_skb+0x18/0x60 [] netif_receive_skb_internal+0x40/0xb0 [] netif_receive_skb+0x1c/0x70 [] br_pass_frame_up+0xc6/0x160 [bridge] [] ? deliver_clone+0x37/0x50 [bridge] [] ? br_flood+0xcc/0x160 [bridge] [] br_handle_frame_finish+0x224/0x4f0 [bridge] [] br_handle_frame+0x174/0x300 [bridge] [] __netif_receive_skb_core+0x329/0xab0 [] ? find_next_bit+0x15/0x20 [] ? cpumask_next_and+0x32/0x50 [] ? load_balance+0x178/0x9b0 [] __netif_receive_skb+0x18/0x60 [] netif_receive_skb_internal+0x40/0xb0 [] netif_receive_skb+0x1c/0x70 [] mlxsw_sp_rx_listener_func+0x61/0xb0 [mlxsw_spectrum] [] mlxsw_core_skb_receive+0x187/0x200 [mlxsw_core] [] mlxsw_pci_cq_tasklet+0x63a/0x9b0 [mlxsw_pci] [] tasklet_action+0xf6/0x110 [] __do_softirq+0xf6/0x280 [] irq_exit+0xdf/0xf0 [] do_IRQ+0x54/0xd0 [] common_interrupt+0x8c/0x8c The problem is that netdev_all_lower_get_next_rcu() never advances the iterator, thereby causing the loop over the lower adjacency list to run forever. Fix this by advancing the iterator and avoid the infinite loop. Fixes: 7ce856aaaf13 ("mlxsw: spectrum: Add couple of lower device helper functions") Signed-off-by: Ido Schimmel Reported-by: Tamir Winetroub Reviewed-by: Jiri Pirko Acked-by: David Ahern Signed-off-by: David S. Miller

Merge tag 'gcc-plugins-v4.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux

2016-10-15T17:03:15Z

Pull gcc plugins update from Kees Cook: "This adds a new gcc plugin named "latent_entropy". It is designed to extract as much possible uncertainty from a running system at boot time as possible, hoping to capitalize on any possible variation in CPU operation (due to runtime data differences, hardware differences, SMP ordering, thermal timing variation, cache behavior, etc). At the very least, this plugin is a much more comprehensive example for how to manipulate kernel code using the gcc plugin internals" * tag 'gcc-plugins-v4.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux: latent_entropy: Mark functions with __latent_entropy gcc-plugins: Add latent_entropy plugin

latent_entropy: Mark functions with __latent_entropy

2016-10-10T21:51:45Z

The __latent_entropy gcc attribute can be used only on functions and variables. If it is on a function then the plugin will instrument it for gathering control-flow entropy. If the attribute is on a variable then the plugin will initialize it with random contents. The variable must be an integer, an integer array type or a structure with integer fields. These specific functions have been selected because they are init functions (to help gather boot-time entropy), are called at unpredictable times, or they have variable loops, each of which provide some level of latent entropy. Signed-off-by: Emese Revfy [kees: expanded commit message] Signed-off-by: Kees Cook

net: Add netdev all_adj_list refcnt propagation to fix panic

2016-10-04T06:05:31Z

This is a respin of a patch to fix a relatively easily reproducible kernel panic related to the all_adj_list handling for netdevs in recent kernels. The following sequence of commands will reproduce the issue: ip link add link eth0 name eth0.100 type vlan id 100 ip link add link eth0 name eth0.200 type vlan id 200 ip link add name testbr type bridge ip link set eth0.100 master testbr ip link set eth0.200 master testbr ip link add link testbr mac0 type macvlan ip link delete dev testbr This creates an upper/lower tree of (excuse the poor ASCII art): /---eth0.100-eth0 mac0-testbr- \---eth0.200-eth0 When testbr is deleted, the all_adj_lists are walked, and eth0 is deleted twice from the mac0 list. Unfortunately, during setup in __netdev_upper_dev_link, only one reference to eth0 is added, so this results in a panic. This change adds reference count propagation so things are handled properly. Matthias Schiffer reported a similar crash in batman-adv: https://github.com/freifunk-gluon/gluon/issues/680 https://www.open-mesh.org/issues/247 which this patch also seems to resolve. Signed-off-by: Andrew Collins Signed-off-by: David S. Miller

Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next

2016-09-25T21:34:19Z

Conflicts: net/netfilter/core.c net/netfilter/nf_tables_netdev.c Resolve two conflicts before pull request for David's net-next tree: 1) Between c73c24849011 ("netfilter: nf_tables_netdev: remove redundant ip_hdr assignment") from the net tree and commit ddc8b6027ad0 ("netfilter: introduce nft_set_pktinfo_{ipv4, ipv6}_validate()"). 2) Between e8bffe0cf964 ("net: Add _nf_(un)register_hooks symbols") and Aaron Conole's patches to replace list_head with single linked list. Signed-off-by: Pablo Neira Ayuso