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* netfilter: conntrack: do not enable connection tracking unless neededFlorian Westphal2017-07-316-94/+4
| | | | | | | | | | | | | | | | | | | | | | | Discussion during NFWS 2017 in Faro has shown that the current conntrack behaviour is unreasonable. Even if conntrack module is loaded on behalf of a single net namespace, its turned on for all namespaces, which is expensive. Commit 481fa373476 ("netfilter: conntrack: add nf_conntrack_default_on sysctl") attempted to provide an alternative to the 'default on' behaviour by adding a sysctl to change it. However, as Eric points out, the sysctl only becomes available once the module is loaded, and then its too late. So we either have to move the sysctl to the core, or, alternatively, change conntrack to become active only once the rule set requires this. This does the latter, conntrack is only enabled when a rule needs it. Reported-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
* netfilter: nft_set_rbtree: use seqcount to avoid lock in most casesFlorian Westphal2017-07-311-12/+37
| | | | | | | | | | | | | | | | | | | switch to lockless lockup. write side now also increments sequence counter. On lookup, sample counter value and only take the lock if we did not find a match and the counter has changed. This avoids need to write to private area in normal (lookup) cases. In case we detect a writer (seqretry is true) we fall back to taking the readlock. The readlock is also used during dumps to ensure we get a consistent tree walk. Similar technique (rbtree+seqlock) was used by David Howells in rxrpc. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
* netfilter: nf_tables: Allow object names of up to 255 charsPhil Sutter2017-07-313-4/+11
| | | | | | | | Same conversion as for table names, use NFT_NAME_MAXLEN as upper boundary as well. Signed-off-by: Phil Sutter <phil@nwl.cc> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
* netfilter: nf_tables: Allow set names of up to 255 charsPhil Sutter2017-07-313-6/+16
| | | | | | | | Same conversion as for table names, use NFT_NAME_MAXLEN as upper boundary as well. Signed-off-by: Phil Sutter <phil@nwl.cc> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
* netfilter: nf_tables: Allow chain name of up to 255 charsPhil Sutter2017-07-314-13/+54
| | | | | | | | Same conversion as for table names, use NFT_NAME_MAXLEN as upper boundary as well. Signed-off-by: Phil Sutter <phil@nwl.cc> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
* netfilter: nf_tables: Allow table names of up to 255 charsPhil Sutter2017-07-314-16/+40
| | | | | | | | | Allocate all table names dynamically to allow for arbitrary lengths but introduce NFT_NAME_MAXLEN as an upper sanity boundary. It's value was chosen to allow using a domain name as per RFC 1035. Signed-off-by: Phil Sutter <phil@nwl.cc> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
* netlink: Introduce nla_strdup()Phil Sutter2017-07-312-0/+25
| | | | | | | This is similar to strdup() for netlink string attributes. Signed-off-by: Phil Sutter <phil@nwl.cc> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
* netfilter: nf_tables: No need to check chain existence when tracingPhil Sutter2017-07-311-8/+5
| | | | | | | | | | | | nft_trace_notify() is called only from __nft_trace_packet(), which assigns its parameter 'chain' to info->chain. __nft_trace_packet() in turn later dereferences 'chain' unconditionally, which indicates that it's never NULL. Same does nft_do_chain(), the only user of the tracing infrastructure. Hence it is safe to assume the check removed here is not needed. Signed-off-by: Phil Sutter <phil@nwl.cc> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
* netfilter: nf_hook_ops structs can be constFlorian Westphal2017-07-3118-18/+18
| | | | | | | We no longer place these on a list so they can be const. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
* netfilter: nfnetlink_queue: don't queue dying conntracks to userspaceFlorian Westphal2017-07-311-0/+19
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When skb is queued to userspace it leaves softirq/rcu protection. skb->nfct (via conntrack extensions such as helper) could then reference modules that no longer exist if the conntrack was not yet confirmed. nf_ct_iterate_destroy() will set the DYING bit for unconfirmed conntracks, we therefore solve this race as follows: 1. take the queue spinlock. 2. check if the conntrack is unconfirmed and has dying bit set. In this case, we must discard skb while we're still inside rcu read-side section. 3. If nf_ct_iterate_destroy() is called right after the packet is queued to userspace, it will be removed from the queue via nf_ct_iterate_destroy -> nf_queue_nf_hook_drop. When userspace sends the verdict (nfnetlink takes rcu read lock), there are two cases to consider: 1. nf_ct_iterate_destroy() was called while packet was out. In this case, skb will have been removed from the queue already and no reinject takes place as we won't find a matching entry for the packet id. 2. nf_ct_iterate_destroy() gets called right after verdict callback found and removed the skb from queue list. In this case, skb->nfct is marked as dying but it is still valid. The skb will be dropped either in nf_conntrack_confirm (we don't insert DYING conntracks into hash table) or when we try to queue the skb again, but either events don't occur before the rcu read lock is dropped. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
* netfilter: conntrack: destroy functions need to free queued packetsFlorian Westphal2017-07-312-0/+5
| | | | | | | | | | | | | | queued skbs might be using conntrack extensions that are being removed, such as timeout. This happens for skbs that have a skb->nfct in unconfirmed state (i.e., not in hash table yet). This is destructive, but there are only two use cases: - module removal (rare) - netns cleanup (most likely no conntracks exist, and if they do, they are removed anyway later on). Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
* netfilter: add and use nf_ct_unconfirmed_destroyFlorian Westphal2017-07-313-4/+15
| | | | | | | | | This also removes __nf_ct_unconfirmed_destroy() call from nf_ct_iterate_cleanup_net, so that function can be used only when missing conntracks from unconfirmed list isn't a problem. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
* netfilter: expect: add and use nf_ct_expect_iterate helpersFlorian Westphal2017-07-314-61/+95
| | | | | | | | We have several spots that open-code a expect walk, add a helper that is similar to nf_ct_iterate_destroy/nf_ct_iterate_cleanup. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
* netfilter: conntrack: Change to deferable work queuesubashab@codeaurora.org2017-07-311-1/+1
| | | | | | | | | Delayed workqueue causes wakeups to idle CPUs. This was causing a power impact for devices. Use deferable work queue instead so that gc_worker runs when CPU is active only. Signed-off-by: Subash Abhinov Kasiviswanathan <subashab@codeaurora.org> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
* netfilter: nf_tables: add fib expression to the netdev familyPablo M. Bermudo Garay2017-07-313-0/+97
| | | | | | | | | | | | | | | Add fib expression support for netdev family. Like inet family, netdev delegates the actual decision to the corresponding backend, either ipv4 or ipv6. This allows to perform very early reverse path filtering, among other things. You can find more information about fib expression in the f6d0cbcf09c5 ("<netfilter: nf_tables: add fib expression>") commit message. Signed-off-by: Pablo M. Bermudo Garay <pablombg@gmail.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
* netfilter: nf_tables: fib: use skb_header_pointerPablo M. Bermudo Garay2017-07-312-10/+39
| | | | | | | | | | | | This is a preparatory patch for adding fib support to the netdev family. The netdev family receives the packets from ingress hook. At this point we have no guarantee that the ip header is linear. So this patch replaces ip_hdr with skb_header_pointer in order to address that possible situation. Signed-off-by: Pablo M. Bermudo Garay <pablombg@gmail.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
* netfilter: nf_tables: Attach process info to NFT_MSG_NEWGEN notificationsPhil Sutter2017-07-242-1/+6
| | | | | | | | This is helpful for 'nft monitor' to track which process caused a given change to the ruleset. Signed-off-by: Phil Sutter <phil@nwl.cc> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
* netfilter: Remove duplicated rcu_read_lock.Taehee Yoo2017-07-2420-128/+13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch removes duplicate rcu_read_lock(). 1. IPVS part: According to Julian Anastasov's mention, contexts of ipvs are described at: http://marc.info/?l=netfilter-devel&m=149562884514072&w=2, in summary: - packet RX/TX: does not need locks because packets come from hooks. - sync msg RX: backup server uses RCU locks while registering new connections. - ip_vs_ctl.c: configuration get/set, RCU locks needed. - xt_ipvs.c: It is a netfilter match, running from hook context. As result, rcu_read_lock and rcu_read_unlock can be removed from: - ip_vs_core.c: all - ip_vs_ctl.c: - only from ip_vs_has_real_service - ip_vs_ftp.c: all - ip_vs_proto_sctp.c: all - ip_vs_proto_tcp.c: all - ip_vs_proto_udp.c: all - ip_vs_xmit.c: all (contains only packet processing) 2. Netfilter part: There are three types of functions that are guaranteed the rcu_read_lock(). First, as result, functions are only called by nf_hook(): - nf_conntrack_broadcast_help(), pptp_expectfn(), set_expected_rtp_rtcp(). - tcpmss_reverse_mtu(), tproxy_laddr4(), tproxy_laddr6(). - match_lookup_rt6(), check_hlist(), hashlimit_mt_common(). - xt_osf_match_packet(). Second, functions that caller already held the rcu_read_lock(). - destroy_conntrack(), ctnetlink_conntrack_event(). - ctnl_timeout_find_get(), nfqnl_nf_hook_drop(). Third, functions that are mixed with type1 and type2. These functions are called by nf_hook() also these are called by ordinary functions that already held the rcu_read_lock(): - __ctnetlink_glue_build(), ctnetlink_expect_event(). - ctnetlink_proto_size(). Applied files are below: - nf_conntrack_broadcast.c, nf_conntrack_core.c, nf_conntrack_netlink.c. - nf_conntrack_pptp.c, nf_conntrack_sip.c, nfnetlink_cttimeout.c. - nfnetlink_queue.c, xt_TCPMSS.c, xt_TPROXY.c, xt_addrtype.c. - xt_connlimit.c, xt_hashlimit.c, xt_osf.c Detailed calltrace can be found at: http://marc.info/?l=netfilter-devel&m=149667610710350&w=2 Signed-off-by: Taehee Yoo <ap420073@gmail.com> Acked-by: Julian Anastasov <ja@ssi.bg> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
* netfilter: nf_tables: keep chain counters away from hot pathPablo Neira Ayuso2017-07-243-16/+23
| | | | | | | | | These chain counters are only used by the iptables-compat tool, that allow users to use the x_tables extensions from the existing nf_tables framework. This patch makes nf_tables by ~5% for the general usecase, ie. native nft users, where no chain counters are used at all. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
* netfilter: expect: add to hash table after expect initFlorian Westphal2017-07-241-6/+6
| | | | | | | | | | | | | assuming we have lockless readers we should make sure they can only see expectations that have already been initialized. hlist_add_head_rcu acts as memory barrier, move it after timer setup. Theoretically we could crash due to a del_timer() on other cpu seeing garbage data. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
* Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller2017-07-211200-18852/+38137
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| * Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netLinus Torvalds2017-07-2183-581/+1176
| |\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull networking fixes from David Miller: 1) BPF verifier signed/unsigned value tracking fix, from Daniel Borkmann, Edward Cree, and Josef Bacik. 2) Fix memory allocation length when setting up calls to ->ndo_set_mac_address, from Cong Wang. 3) Add a new cxgb4 device ID, from Ganesh Goudar. 4) Fix FIB refcount handling, we have to set it's initial value before the configure callback (which can bump it). From David Ahern. 5) Fix double-free in qcom/emac driver, from Timur Tabi. 6) A bunch of gcc-7 string format overflow warning fixes from Arnd Bergmann. 7) Fix link level headroom tests in ip_do_fragment(), from Vasily Averin. 8) Fix chunk walking in SCTP when iterating over error and parameter headers. From Alexander Potapenko. 9) TCP BBR congestion control fixes from Neal Cardwell. 10) Fix SKB fragment handling in bcmgenet driver, from Doug Berger. 11) BPF_CGROUP_RUN_PROG_SOCK_OPS needs to check for null __sk, from Cong Wang. 12) xmit_recursion in ppp driver needs to be per-device not per-cpu, from Gao Feng. 13) Cannot release skb->dst in UDP if IP options processing needs it. From Paolo Abeni. 14) Some netdev ioctl ifr_name[] NULL termination fixes. From Alexander Levin and myself. 15) Revert some rtnetlink notification changes that are causing regressions, from David Ahern. * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (83 commits) net: bonding: Fix transmit load balancing in balance-alb mode rds: Make sure updates to cp_send_gen can be observed net: ethernet: ti: cpsw: Push the request_irq function to the end of probe ipv4: initialize fib_trie prior to register_netdev_notifier call. rtnetlink: allocate more memory for dev_set_mac_address() net: dsa: b53: Add missing ARL entries for BCM53125 bpf: more tests for mixed signed and unsigned bounds checks bpf: add test for mixed signed and unsigned bounds checks bpf: fix up test cases with mixed signed/unsigned bounds bpf: allow to specify log level and reduce it for test_verifier bpf: fix mixed signed/unsigned derived min/max value bounds ipv6: avoid overflow of offset in ip6_find_1stfragopt net: tehuti: don't process data if it has not been copied from userspace Revert "rtnetlink: Do not generate notifications for CHANGEADDR event" net: dsa: mv88e6xxx: Enable CMODE config support for 6390X dt-binding: ptp: Add SoC compatibility strings for dte ptp clock NET: dwmac: Make dwmac reset unconditional net: Zero terminate ifr_name in dev_ifname(). wireless: wext: terminate ifr name coming from userspace netfilter: fix netfilter_net_init() return ...
| | * net: bonding: Fix transmit load balancing in balance-alb modeKosuke Tatsukawa2017-07-211-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | balance-alb mode used to have transmit dynamic load balancing feature enabled by default. However, transmit dynamic load balancing no longer works in balance-alb after commit 8b426dc54cf4 ("bonding: remove hardcoded value"). Both balance-tlb and balance-alb use the function bond_do_alb_xmit() to send packets. This function uses the parameter tlb_dynamic_lb. tlb_dynamic_lb used to have the default value of 1 for balance-alb, but now the value is set to 0 except in balance-tlb. Re-enable transmit dyanmic load balancing by initializing tlb_dynamic_lb for balance-alb similar to balance-tlb. Fixes: 8b426dc54cf4 ("bonding: remove hardcoded value") Signed-off-by: Kosuke Tatsukawa <tatsu@ab.jp.nec.com> Acked-by: Andy Gospodarek <andy@greyhouse.net> Signed-off-by: David S. Miller <davem@davemloft.net>
| | * rds: Make sure updates to cp_send_gen can be observedHåkon Bugge2017-07-211-3/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | cp->cp_send_gen is treated as a normal variable, although it may be used by different threads. This is fixed by using {READ,WRITE}_ONCE when it is incremented and READ_ONCE when it is read outside the {acquire,release}_in_xmit protection. Normative reference from the Linux-Kernel Memory Model: Loads from and stores to shared (but non-atomic) variables should be protected with the READ_ONCE(), WRITE_ONCE(), and ACCESS_ONCE(). Clause 5.1.2.4/25 in the C standard is also relevant. Signed-off-by: Håkon Bugge <haakon.bugge@oracle.com> Reviewed-by: Knut Omang <knut.omang@oracle.com> Acked-by: Santosh Shilimkar <santosh.shilimkar@oracle.com> Signed-off-by: David S. Miller <davem@davemloft.net>
| | * net: ethernet: ti: cpsw: Push the request_irq function to the end of probeKeerthy2017-07-211-24/+25
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Push the request_irq function to the end of probe so as to ensure all the required fields are populated in the event of an ISR getting executed right after requesting the irq. Currently while loading the crash kernel a crash was seen as soon as devm_request_threaded_irq was called. This was due to n->poll being NULL which is called as part of net_rx_action function. Suggested-by: Sekhar Nori <nsekhar@ti.com> Signed-off-by: Keerthy <j-keerthy@ti.com> Signed-off-by: David S. Miller <davem@davemloft.net>
| | * ipv4: initialize fib_trie prior to register_netdev_notifier call.Mahesh Bandewar2017-07-211-4/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Net stack initialization currently initializes fib-trie after the first call to netdevice_notifier() call. In fact fib_trie initialization needs to happen before first rtnl_register(). It does not cause any problem since there are no devices UP at this moment, but trying to bring 'lo' UP at initialization would make this assumption wrong and exposes the issue. Fixes following crash Call Trace: ? alternate_node_alloc+0x76/0xa0 fib_table_insert+0x1b7/0x4b0 fib_magic.isra.17+0xea/0x120 fib_add_ifaddr+0x7b/0x190 fib_netdev_event+0xc0/0x130 register_netdevice_notifier+0x1c1/0x1d0 ip_fib_init+0x72/0x85 ip_rt_init+0x187/0x1e9 ip_init+0xe/0x1a inet_init+0x171/0x26c ? ipv4_offload_init+0x66/0x66 do_one_initcall+0x43/0x160 kernel_init_freeable+0x191/0x219 ? rest_init+0x80/0x80 kernel_init+0xe/0x150 ret_from_fork+0x22/0x30 Code: f6 46 23 04 74 86 4c 89 f7 e8 ae 45 01 00 49 89 c7 4d 85 ff 0f 85 7b ff ff ff 31 db eb 08 4c 89 ff e8 16 47 01 00 48 8b 44 24 38 <45> 8b 6e 14 4d 63 76 74 48 89 04 24 0f 1f 44 00 00 48 83 c4 08 RIP: kmem_cache_alloc+0xcf/0x1c0 RSP: ffff9b1500017c28 CR2: 0000000000000014 Fixes: 7b1a74fdbb9e ("[NETNS]: Refactor fib initialization so it can handle multiple namespaces.") Fixes: 7f9b80529b8a ("[IPV4]: fib hash|trie initialization") Signed-off-by: Mahesh Bandewar <maheshb@google.com> Acked-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
| | * rtnetlink: allocate more memory for dev_set_mac_address()WANG Cong2017-07-211-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | virtnet_set_mac_address() interprets mac address as struct sockaddr, but upper layer only allocates dev->addr_len which is ETH_ALEN + sizeof(sa_family_t) in this case. We lack a unified definition for mac address, so just fix the upper layer, this also allows drivers to interpret it to struct sockaddr freely. Reported-by: David Ahern <dsahern@gmail.com> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
| | * net: dsa: b53: Add missing ARL entries for BCM53125Florian Fainelli2017-07-211-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The BCM53125 entry was missing an arl_entries member which would basically prevent the ARL search from terminating properly. This switch has 4 ARL entries, so add that. Fixes: 1da6df85c6fb ("net: dsa: b53: Implement ARL add/del/dump operations") Signed-off-by: Florian Fainelli <f.fainelli@gmail.com> Reviewed-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com> Signed-off-by: David S. Miller <davem@davemloft.net>
| | * Merge branch 'BPF-map-value-adjust-fix'David S. Miller2017-07-216-23/+574
| | |\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Daniel Borkmann says: ==================== BPF map value adjust fix First patch in the series is the actual fix and the remaining patches are just updates to selftests. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
| | | * bpf: more tests for mixed signed and unsigned bounds checksDaniel Borkmann2017-07-211-0/+418
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add a couple of more test cases to BPF selftests that are related to mixed signed and unsigned checks. Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
| | | * bpf: add test for mixed signed and unsigned bounds checksEdward Cree2017-07-211-0/+52
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | These failed due to a bug in verifier bounds handling. Signed-off-by: Edward Cree <ecree@solarflare.com> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
| | | * bpf: fix up test cases with mixed signed/unsigned boundsDaniel Borkmann2017-07-211-4/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Fix the few existing test cases that used mixed signed/unsigned bounds and switch them only to one flavor. Reason why we need this is that proper boundaries cannot be derived from mixed tests. Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
| | | * bpf: allow to specify log level and reduce it for test_verifierDaniel Borkmann2017-07-214-5/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | For the test_verifier case, it's quite hard to parse log level 2 to figure out what's causing an issue when used to log level 1. We do want to use bpf_verify_program() in order to simulate some of the tests with strict alignment. So just add an argument to pass the level and put it to 1 for test_verifier. Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
| | | * bpf: fix mixed signed/unsigned derived min/max value boundsDaniel Borkmann2017-07-212-14/+95
| | |/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Edward reported that there's an issue in min/max value bounds tracking when signed and unsigned compares both provide hints on limits when having unknown variables. E.g. a program such as the following should have been rejected: 0: (7a) *(u64 *)(r10 -8) = 0 1: (bf) r2 = r10 2: (07) r2 += -8 3: (18) r1 = 0xffff8a94cda93400 5: (85) call bpf_map_lookup_elem#1 6: (15) if r0 == 0x0 goto pc+7 R0=map_value(ks=8,vs=8,id=0),min_value=0,max_value=0 R10=fp 7: (7a) *(u64 *)(r10 -16) = -8 8: (79) r1 = *(u64 *)(r10 -16) 9: (b7) r2 = -1 10: (2d) if r1 > r2 goto pc+3 R0=map_value(ks=8,vs=8,id=0),min_value=0,max_value=0 R1=inv,min_value=0 R2=imm-1,max_value=18446744073709551615,min_align=1 R10=fp 11: (65) if r1 s> 0x1 goto pc+2 R0=map_value(ks=8,vs=8,id=0),min_value=0,max_value=0 R1=inv,min_value=0,max_value=1 R2=imm-1,max_value=18446744073709551615,min_align=1 R10=fp 12: (0f) r0 += r1 13: (72) *(u8 *)(r0 +0) = 0 R0=map_value_adj(ks=8,vs=8,id=0),min_value=0,max_value=1 R1=inv,min_value=0,max_value=1 R2=imm-1,max_value=18446744073709551615,min_align=1 R10=fp 14: (b7) r0 = 0 15: (95) exit What happens is that in the first part ... 8: (79) r1 = *(u64 *)(r10 -16) 9: (b7) r2 = -1 10: (2d) if r1 > r2 goto pc+3 ... r1 carries an unsigned value, and is compared as unsigned against a register carrying an immediate. Verifier deduces in reg_set_min_max() that since the compare is unsigned and operation is greater than (>), that in the fall-through/false case, r1's minimum bound must be 0 and maximum bound must be r2. Latter is larger than the bound and thus max value is reset back to being 'invalid' aka BPF_REGISTER_MAX_RANGE. Thus, r1 state is now 'R1=inv,min_value=0'. The subsequent test ... 11: (65) if r1 s> 0x1 goto pc+2 ... is a signed compare of r1 with immediate value 1. Here, verifier deduces in reg_set_min_max() that since the compare is signed this time and operation is greater than (>), that in the fall-through/false case, we can deduce that r1's maximum bound must be 1, meaning with prior test, we result in r1 having the following state: R1=inv,min_value=0,max_value=1. Given that the actual value this holds is -8, the bounds are wrongly deduced. When this is being added to r0 which holds the map_value(_adj) type, then subsequent store access in above case will go through check_mem_access() which invokes check_map_access_adj(), that will then probe whether the map memory is in bounds based on the min_value and max_value as well as access size since the actual unknown value is min_value <= x <= max_value; commit fce366a9dd0d ("bpf, verifier: fix alu ops against map_value{, _adj} register types") provides some more explanation on the semantics. It's worth to note in this context that in the current code, min_value and max_value tracking are used for two things, i) dynamic map value access via check_map_access_adj() and since commit 06c1c049721a ("bpf: allow helpers access to variable memory") ii) also enforced at check_helper_mem_access() when passing a memory address (pointer to packet, map value, stack) and length pair to a helper and the length in this case is an unknown value defining an access range through min_value/max_value in that case. The min_value/max_value tracking is /not/ used in the direct packet access case to track ranges. However, the issue also affects case ii), for example, the following crafted program based on the same principle must be rejected as well: 0: (b7) r2 = 0 1: (bf) r3 = r10 2: (07) r3 += -512 3: (7a) *(u64 *)(r10 -16) = -8 4: (79) r4 = *(u64 *)(r10 -16) 5: (b7) r6 = -1 6: (2d) if r4 > r6 goto pc+5 R1=ctx R2=imm0,min_value=0,max_value=0,min_align=2147483648 R3=fp-512 R4=inv,min_value=0 R6=imm-1,max_value=18446744073709551615,min_align=1 R10=fp 7: (65) if r4 s> 0x1 goto pc+4 R1=ctx R2=imm0,min_value=0,max_value=0,min_align=2147483648 R3=fp-512 R4=inv,min_value=0,max_value=1 R6=imm-1,max_value=18446744073709551615,min_align=1 R10=fp 8: (07) r4 += 1 9: (b7) r5 = 0 10: (6a) *(u16 *)(r10 -512) = 0 11: (85) call bpf_skb_load_bytes#26 12: (b7) r0 = 0 13: (95) exit Meaning, while we initialize the max_value stack slot that the verifier thinks we access in the [1,2] range, in reality we pass -7 as length which is interpreted as u32 in the helper. Thus, this issue is relevant also for the case of helper ranges. Resetting both bounds in check_reg_overflow() in case only one of them exceeds limits is also not enough as similar test can be created that uses values which are within range, thus also here learned min value in r1 is incorrect when mixed with later signed test to create a range: 0: (7a) *(u64 *)(r10 -8) = 0 1: (bf) r2 = r10 2: (07) r2 += -8 3: (18) r1 = 0xffff880ad081fa00 5: (85) call bpf_map_lookup_elem#1 6: (15) if r0 == 0x0 goto pc+7 R0=map_value(ks=8,vs=8,id=0),min_value=0,max_value=0 R10=fp 7: (7a) *(u64 *)(r10 -16) = -8 8: (79) r1 = *(u64 *)(r10 -16) 9: (b7) r2 = 2 10: (3d) if r2 >= r1 goto pc+3 R0=map_value(ks=8,vs=8,id=0),min_value=0,max_value=0 R1=inv,min_value=3 R2=imm2,min_value=2,max_value=2,min_align=2 R10=fp 11: (65) if r1 s> 0x4 goto pc+2 R0=map_value(ks=8,vs=8,id=0),min_value=0,max_value=0 R1=inv,min_value=3,max_value=4 R2=imm2,min_value=2,max_value=2,min_align=2 R10=fp 12: (0f) r0 += r1 13: (72) *(u8 *)(r0 +0) = 0 R0=map_value_adj(ks=8,vs=8,id=0),min_value=3,max_value=4 R1=inv,min_value=3,max_value=4 R2=imm2,min_value=2,max_value=2,min_align=2 R10=fp 14: (b7) r0 = 0 15: (95) exit This leaves us with two options for fixing this: i) to invalidate all prior learned information once we switch signed context, ii) to track min/max signed and unsigned boundaries separately as done in [0]. (Given latter introduces major changes throughout the whole verifier, it's rather net-next material, thus this patch follows option i), meaning we can derive bounds either from only signed tests or only unsigned tests.) There is still the case of adjust_reg_min_max_vals(), where we adjust bounds on ALU operations, meaning programs like the following where boundaries on the reg get mixed in context later on when bounds are merged on the dst reg must get rejected, too: 0: (7a) *(u64 *)(r10 -8) = 0 1: (bf) r2 = r10 2: (07) r2 += -8 3: (18) r1 = 0xffff89b2bf87ce00 5: (85) call bpf_map_lookup_elem#1 6: (15) if r0 == 0x0 goto pc+6 R0=map_value(ks=8,vs=8,id=0),min_value=0,max_value=0 R10=fp 7: (7a) *(u64 *)(r10 -16) = -8 8: (79) r1 = *(u64 *)(r10 -16) 9: (b7) r2 = 2 10: (3d) if r2 >= r1 goto pc+2 R0=map_value(ks=8,vs=8,id=0),min_value=0,max_value=0 R1=inv,min_value=3 R2=imm2,min_value=2,max_value=2,min_align=2 R10=fp 11: (b7) r7 = 1 12: (65) if r7 s> 0x0 goto pc+2 R0=map_value(ks=8,vs=8,id=0),min_value=0,max_value=0 R1=inv,min_value=3 R2=imm2,min_value=2,max_value=2,min_align=2 R7=imm1,max_value=0 R10=fp 13: (b7) r0 = 0 14: (95) exit from 12 to 15: R0=map_value(ks=8,vs=8,id=0),min_value=0,max_value=0 R1=inv,min_value=3 R2=imm2,min_value=2,max_value=2,min_align=2 R7=imm1,min_value=1 R10=fp 15: (0f) r7 += r1 16: (65) if r7 s> 0x4 goto pc+2 R0=map_value(ks=8,vs=8,id=0),min_value=0,max_value=0 R1=inv,min_value=3 R2=imm2,min_value=2,max_value=2,min_align=2 R7=inv,min_value=4,max_value=4 R10=fp 17: (0f) r0 += r7 18: (72) *(u8 *)(r0 +0) = 0 R0=map_value_adj(ks=8,vs=8,id=0),min_value=4,max_value=4 R1=inv,min_value=3 R2=imm2,min_value=2,max_value=2,min_align=2 R7=inv,min_value=4,max_value=4 R10=fp 19: (b7) r0 = 0 20: (95) exit Meaning, in adjust_reg_min_max_vals() we must also reset range values on the dst when src/dst registers have mixed signed/ unsigned derived min/max value bounds with one unbounded value as otherwise they can be added together deducing false boundaries. Once both boundaries are established from either ALU ops or compare operations w/o mixing signed/unsigned insns, then they can safely be added to other regs also having both boundaries established. Adding regs with one unbounded side to a map value where the bounded side has been learned w/o mixing ops is possible, but the resulting map value won't recover from that, meaning such op is considered invalid on the time of actual access. Invalid bounds are set on the dst reg in case i) src reg, or ii) in case dst reg already had them. The only way to recover would be to perform i) ALU ops but only 'add' is allowed on map value types or ii) comparisons, but these are disallowed on pointers in case they span a range. This is fine as only BPF_JEQ and BPF_JNE may be performed on PTR_TO_MAP_VALUE_OR_NULL registers which potentially turn them into PTR_TO_MAP_VALUE type depending on the branch, so only here min/max value cannot be invalidated for them. In terms of state pruning, value_from_signed is considered as well in states_equal() when dealing with adjusted map values. With regards to breaking existing programs, there is a small risk, but use-cases are rather quite narrow where this could occur and mixing compares probably unlikely. Joint work with Josef and Edward. [0] https://lists.iovisor.org/pipermail/iovisor-dev/2017-June/000822.html Fixes: 484611357c19 ("bpf: allow access into map value arrays") Reported-by: Edward Cree <ecree@solarflare.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: Edward Cree <ecree@solarflare.com> Signed-off-by: Josef Bacik <jbacik@fb.com> Signed-off-by: David S. Miller <davem@davemloft.net>
| | * ipv6: avoid overflow of offset in ip6_find_1stfragoptSabrina Dubroca2017-07-201-2/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In some cases, offset can overflow and can cause an infinite loop in ip6_find_1stfragopt(). Make it unsigned int to prevent the overflow, and cap it at IPV6_MAXPLEN, since packets larger than that should be invalid. This problem has been here since before the beginning of git history. Signed-off-by: Sabrina Dubroca <sd@queasysnail.net> Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: David S. Miller <davem@davemloft.net>
| | * net: tehuti: don't process data if it has not been copied from userspaceColin Ian King2017-07-201-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The array data is only populated with valid information from userspace if cmd != SIOCDEVPRIVATE, other cases the array contains garbage on the stack. The subsequent switch statement acts on a subcommand in data[0] which could be any garbage value if cmd is SIOCDEVPRIVATE which seems incorrect to me. Instead, just return EOPNOTSUPP for the case where cmd == SIOCDEVPRIVATE to avoid this issue. As a side note, I suspect that the original intention of the code was for this ioctl to work just for cmd == SIOCDEVPRIVATE (and the current logic is reversed). However, I don't wont to change the current semantics in case any userspace code relies on this existing behaviour. Detected by CoverityScan, CID#139647 ("Uninitialized scalar variable") Signed-off-by: Colin Ian King <colin.king@canonical.com> Signed-off-by: David S. Miller <davem@davemloft.net>
| | * Revert "rtnetlink: Do not generate notifications for CHANGEADDR event"David Ahern2017-07-201-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This reverts commit cd8966e75ed3c6b41a37047a904617bc44fa481f. The duplicate CHANGEADDR event message is sent regardless of link status whereas the setlink changes only generate a notification when the link is up. Not sending a notification when the link is down breaks dhcpcd which only processes hwaddr changes when the link is down. Fixes reported regression: https://bugzilla.kernel.org/show_bug.cgi?id=196355 Reported-by: Yaroslav Isakov <yaroslav.isakov@gmail.com> Signed-off-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
| | * net: dsa: mv88e6xxx: Enable CMODE config support for 6390XMartin Hundebøll2017-07-201-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit f39908d3b1c45 ('net: dsa: mv88e6xxx: Set the CMODE for mv88e6390 ports 9 & 10') added support for setting the CMODE for the 6390X family, but only enabled it for 9290 and 6390 - and left out 6390X. Fix support for setting the CMODE on 6390X also by assigning mv88e6390x_port_set_cmode() to the .port_set_cmode function pointer in mv88e6390x_ops too. Fixes: f39908d3b1c4 ("net: dsa: mv88e6xxx: Set the CMODE for mv88e6390 ports 9 & 10") Signed-off-by: Martin Hundebøll <mnhu@prevas.dk> Reviewed-by: Andrew Lunn <andrew@lunn.ch> Reviewed-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com> Signed-off-by: David S. Miller <davem@davemloft.net>
| | * dt-binding: ptp: Add SoC compatibility strings for dte ptp clockArun Parameswaran2017-07-201-4/+11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add SoC specific compatibility strings to the Broadcom DTE based PTP clock binding document. Fixed the document heading and node name. Fixes: 80d6076140b2 ("dt-binding: ptp: add bindings document for dte based ptp clock") Signed-off-by: Arun Parameswaran <arun.parameswaran@broadcom.com> Acked-by: Rob Herring <robh@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
| | * NET: dwmac: Make dwmac reset unconditionalEugeniy Paltsev2017-07-191-1/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Unconditional reset dwmac before HW init if reset controller is present. In existing implementation we reset dwmac only after second module probing: (module load -> unload -> load again [reset happens]) Now we reset dwmac at every module load: (module load [reset happens] -> unload -> load again [reset happens]) Also some reset controllers have only reset callback instead of assert + deassert callbacks pair, so handle this case. Signed-off-by: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com> Signed-off-by: David S. Miller <davem@davemloft.net>
| | * net: Zero terminate ifr_name in dev_ifname().David S. Miller2017-07-191-0/+1
| | | | | | | | | | | | | | | | | | The ifr.ifr_name is passed around and assumed to be NULL terminated. Signed-off-by: David S. Miller <davem@davemloft.net>
| | * wireless: wext: terminate ifr name coming from userspaceLevin, Alexander2017-07-191-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | ifr name is assumed to be a valid string by the kernel, but nothing was forcing username to pass a valid string. In turn, this would cause panics as we tried to access the string past it's valid memory. Signed-off-by: Sasha Levin <alexander.levin@verizon.com> Signed-off-by: David S. Miller <davem@davemloft.net>
| | * netfilter: fix netfilter_net_init() returnDan Carpenter2017-07-181-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | We accidentally return an uninitialized variable. Fixes: cf56c2f892a8 ("netfilter: remove old pre-netns era hook api") Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Acked-by: Pablo Neira Ayuso <pablo@netfilter.org> Signed-off-by: David S. Miller <davem@davemloft.net>
| | * Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nfDavid S. Miller2017-07-186-166/+14
| | |\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pablo Neira Ayuso says: ==================== Netfilter fixes for net The following patchset contains Netfilter fixes for your net tree, they are: 1) Missing netlink message sanity check in nfnetlink, patch from Mateusz Jurczyk. 2) We now have netfilter per-netns hooks, so let's kill global hook infrastructure, this infrastructure is known to be racy with netns. We don't care about out of tree modules. Patch from Florian Westphal. 3) find_appropriate_src() is buggy when colissions happens after the conversion of the nat bysource to rhashtable. Also from Florian. 4) Remove forward chain in nf_tables arp family, it's useless and it is causing quite a bit of confusion, from Florian Westphal. 5) nf_ct_remove_expect() is called with the wrong parameter, causing kernel oops, patch from Florian Westphal. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
| | | * netfilter: expect: fix crash when putting uninited expectationFlorian Westphal2017-07-171-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We crash in __nf_ct_expect_check, it calls nf_ct_remove_expect on the uninitialised expectation instead of existing one, so del_timer chokes on random memory address. Fixes: ec0e3f01114ad32711243 ("netfilter: nf_ct_expect: Add nf_ct_remove_expect()") Reported-by: Sergey Kvachonok <ravenexp@gmail.com> Tested-by: Sergey Kvachonok <ravenexp@gmail.com> Cc: Gao Feng <fgao@ikuai8.com> Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
| | | * netfilter: nf_tables: only allow in/output for arp packetsFlorian Westphal2017-07-171-2/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | arp packets cannot be forwarded. They can be bridged, but then they can be filtered using either ebtables or nftables bridge family. The bridge netfilter exposes a "call-arptables" switch which pushes packets into arptables, but lets not expose this for nftables, so better close this asap. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
| | | * netfilter: nat: fix src map lookupFlorian Westphal2017-07-171-8/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When doing initial conversion to rhashtable I replaced the bucket walk with a single rhashtable_lookup_fast(). When moving to rhlist I failed to properly walk the list of identical tuples, but that is what is needed for this to work correctly. The table contains the original tuples, so the reply tuples are all distinct. We currently decide that mapping is (not) in range only based on the first entry, but in case its not we need to try the reply tuple of the next entry until we either find an in-range mapping or we checked all the entries. This bug makes nat core attempt collision resolution while it might be able to use the mapping as-is. Fixes: 870190a9ec90 ("netfilter: nat: convert nat bysrc hash to rhashtable") Reported-by: Jaco Kroon <jaco@uls.co.za> Tested-by: Jaco Kroon <jaco@uls.co.za> Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
| | | * netfilter: remove old pre-netns era hook apiFlorian Westphal2017-07-172-152/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | no more users in the tree, remove this. The old api is racy wrt. module removal, all users have been converted to the netns-aware api. The old api pretended we still have global hooks but that has not been true for a long time. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
| | | * netfilter: nfnetlink: Improve input length sanitization in nfnetlink_rcvMateusz Jurczyk2017-07-171-3/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Verify that the length of the socket buffer is sufficient to cover the nlmsghdr structure before accessing the nlh->nlmsg_len field for further input sanitization. If the client only supplies 1-3 bytes of data in sk_buff, then nlh->nlmsg_len remains partially uninitialized and contains leftover memory from the corresponding kernel allocation. Operating on such data may result in indeterminate evaluation of the nlmsg_len < NLMSG_HDRLEN expression. The bug was discovered by a runtime instrumentation designed to detect use of uninitialized memory in the kernel. The patch prevents this and other similar tools (e.g. KMSAN) from flagging this behavior in the future. Signed-off-by: Mateusz Jurczyk <mjurczyk@google.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
| | * | udp: preserve skb->dst if required for IP options processingPaolo Abeni2017-07-181-2/+11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Eric noticed that in udp_recvmsg() we still need to access skb->dst while processing the IP options. Since commit 0a463c78d25b ("udp: avoid a cache miss on dequeue") skb->dst is no more available at recvmsg() time and bad things will happen if we enter the relevant code path. This commit address the issue, avoid clearing skb->dst if any IP options are present into the relevant skb. Since the IP CB is contained in the first skb cacheline, we can test it to decide to leverage the consume_stateless_skb() optimization, without measurable additional cost in the faster path. v1 -> v2: updated commit message tags Fixes: 0a463c78d25b ("udp: avoid a cache miss on dequeue") Reported-by: Andrey Konovalov <andreyknvl@google.com> Reported-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>