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* Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-nextDavid S. Miller2021-02-161-4/+3
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Daniel Borkmann says: ==================== pull-request: bpf-next 2021-02-16 The following pull-request contains BPF updates for your *net-next* tree. There's a small merge conflict between 7eeba1706eba ("tcp: Add receive timestamp support for receive zerocopy.") from net-next tree and 9cacf81f8161 ("bpf: Remove extra lock_sock for TCP_ZEROCOPY_RECEIVE") from bpf-next tree. Resolve as follows: [...] lock_sock(sk); err = tcp_zerocopy_receive(sk, &zc, &tss); err = BPF_CGROUP_RUN_PROG_GETSOCKOPT_KERN(sk, level, optname, &zc, &len, err); release_sock(sk); [...] We've added 116 non-merge commits during the last 27 day(s) which contain a total of 156 files changed, 5662 insertions(+), 1489 deletions(-). The main changes are: 1) Adds support of pointers to types with known size among global function args to overcome the limit on max # of allowed args, from Dmitrii Banshchikov. 2) Add bpf_iter for task_vma which can be used to generate information similar to /proc/pid/maps, from Song Liu. 3) Enable bpf_{g,s}etsockopt() from all sock_addr related program hooks. Allow rewriting bind user ports from BPF side below the ip_unprivileged_port_start range, both from Stanislav Fomichev. 4) Prevent recursion on fentry/fexit & sleepable programs and allow map-in-map as well as per-cpu maps for the latter, from Alexei Starovoitov. 5) Add selftest script to run BPF CI locally. Also enable BPF ringbuffer for sleepable programs, both from KP Singh. 6) Extend verifier to enable variable offset read/write access to the BPF program stack, from Andrei Matei. 7) Improve tc & XDP MTU handling and add a new bpf_check_mtu() helper to query device MTU from programs, from Jesper Dangaard Brouer. 8) Allow bpf_get_socket_cookie() helper also be called from [sleepable] BPF tracing programs, from Florent Revest. 9) Extend x86 JIT to pad JMPs with NOPs for helping image to converge when otherwise too many passes are required, from Gary Lin. 10) Verifier fixes on atomics with BPF_FETCH as well as function-by-function verification both related to zero-extension handling, from Ilya Leoshkevich. 11) Better kernel build integration of resolve_btfids tool, from Jiri Olsa. 12) Batch of AF_XDP selftest cleanups and small performance improvement for libbpf's xsk map redirect for newer kernels, from Björn Töpel. 13) Follow-up BPF doc and verifier improvements around atomics with BPF_FETCH, from Brendan Jackman. 14) Permit zero-sized data sections e.g. if ELF .rodata section contains read-only data from local variables, from Yonghong Song. 15) veth driver skb bulk-allocation for ndo_xdp_xmit, from Lorenzo Bianconi. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
| * bpf: Split cgroup_bpf_enabled per attach typeStanislav Fomichev2021-01-201-4/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When we attach any cgroup hook, the rest (even if unused/unattached) start to contribute small overhead. In particular, the one we want to avoid is __cgroup_bpf_run_filter_skb which does two redirections to get to the cgroup and pushes/pulls skb. Let's split cgroup_bpf_enabled to be per-attach to make sure only used attach types trigger. I've dropped some existing high-level cgroup_bpf_enabled in some places because BPF_PROG_CGROUP_XXX_RUN macros usually have another cgroup_bpf_enabled check. I also had to copy-paste BPF_CGROUP_RUN_SA_PROG_LOCK for GETPEERNAME/GETSOCKNAME because type for cgroup_bpf_enabled[type] has to be constant and known at compile time. Signed-off-by: Stanislav Fomichev <sdf@google.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Song Liu <songliubraving@fb.com> Link: https://lore.kernel.org/bpf/20210115163501.805133-4-sdf@google.com
* | udp: call udp_encap_enable for v6 sockets when enabling encapXin Long2021-02-051-1/+3
|/ | | | | | | | | | | | | | | | | | | | | | When enabling encap for a ipv6 socket without udp_encap_needed_key increased, UDP GRO won't work for v4 mapped v6 address packets as sk will be NULL in udp4_gro_receive(). This patch is to enable it by increasing udp_encap_needed_key for v6 sockets in udp_tunnel_encap_enable(), and correspondingly decrease udp_encap_needed_key in udpv6_destroy_sock(). v1->v2: - add udp_encap_disable() and export it. v2->v3: - add the change for rxrpc and bareudp into one patch, as Alex suggested. v3->v4: - move rxrpc part to another patch. Acked-by: Willem de Bruijn <willemb@google.com> Signed-off-by: Xin Long <lucien.xin@gmail.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
* Merge tag 'selinux-pr-20201214' of ↵Linus Torvalds2020-12-161-1/+1
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux Pull selinux updates from Paul Moore: "While we have a small number of SELinux patches for v5.11, there are a few changes worth highlighting: - Change the LSM network hooks to pass flowi_common structs instead of the parent flowi struct as the LSMs do not currently need the full flowi struct and they do not have enough information to use it safely (missing information on the address family). This patch was discussed both with Herbert Xu (representing team netdev) and James Morris (representing team LSMs-other-than-SELinux). - Fix how we handle errors in inode_doinit_with_dentry() so that we attempt to properly label the inode on following lookups instead of continuing to treat it as unlabeled. - Tweak the kernel logic around allowx, auditallowx, and dontauditx SELinux policy statements such that the auditx/dontauditx are effective even without the allowx statement. Everything passes our test suite" * tag 'selinux-pr-20201214' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux: lsm,selinux: pass flowi_common instead of flowi to the LSM hooks selinux: Fix fall-through warnings for Clang selinux: drop super_block backpointer from superblock_security_struct selinux: fix inode_doinit_with_dentry() LABEL_INVALID error handling selinux: allow dontauditx and auditallowx rules to take effect without allowx selinux: fix error initialization in inode_doinit_with_dentry()
| * lsm,selinux: pass flowi_common instead of flowi to the LSM hooksPaul Moore2020-11-241-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | As pointed out by Herbert in a recent related patch, the LSM hooks do not have the necessary address family information to use the flowi struct safely. As none of the LSMs currently use any of the protocol specific flowi information, replace the flowi pointers with pointers to the address family independent flowi_common struct. Reported-by: Herbert Xu <herbert@gondor.apana.org.au> Acked-by: James Morris <jamorris@linux.microsoft.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
* | inet: unexport udp{4|6}_lib_lookup_skb()Eric Dumazet2020-11-151-1/+0
| | | | | | | | | | | | | | | | These functions do not need to be exported. Signed-off-by: Eric Dumazet <edumazet@google.com> Link: https://lore.kernel.org/r/20201113113553.3411756-1-eric.dumazet@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
* | inet: udp{4|6}_lib_lookup_skb() skb argument is constEric Dumazet2020-11-111-1/+1
| | | | | | | | | | | | | | | | | | | | | | The skb is needed only to fetch the keys for the lookup. Both functions are used from GRO stack, we do not want accidental modification of the skb. Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Alexander Lobakin <alobakin@pm.me> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
* | net: udp: introduce UDP_MIB_MEMERRORS for udp_memMenglong Dong2020-11-101-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When udp_memory_allocated is at the limit, __udp_enqueue_schedule_skb will return a -ENOBUFS, and skb will be dropped in __udp_queue_rcv_skb without any counters being done. It's hard to find out what happened once this happen. So we introduce a UDP_MIB_MEMERRORS to do this job. Well, this change looks friendly to the existing users, such as netstat: $ netstat -u -s Udp: 0 packets received 639 packets to unknown port received. 158689 packet receive errors 180022 packets sent RcvbufErrors: 20930 MemErrors: 137759 UdpLite: IpExt: InOctets: 257426235 OutOctets: 257460598 InNoECTPkts: 181177 v2: - Fix some alignment problems Signed-off-by: Menglong Dong <dong.menglong@zte.com.cn> Link: https://lore.kernel.org/r/1604627354-43207-1-git-send-email-dong.menglong@zte.com.cn Signed-off-by: Jakub Kicinski <kuba@kernel.org>
* | udp: check udp sock encap_type in __udp_lib_errXin Long2020-10-301-1/+1
|/ | | | | | | | | | | | | | | There is a chance that __udp4/6_lib_lookup() returns a udp encap sock in __udp_lib_err(), like the udp encap listening sock may use the same port as remote encap port, in which case it should go to __udp4/6_lib_err_encap() for more validation before processing the icmp packet. This patch is to check encap_type in __udp_lib_err() for the further validation for a encap sock. Signed-off-by: Xin Long <lucien.xin@gmail.com> Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
* udp, bpf: Ignore connections in reuseport group after BPF sk lookupJakub Sitnicki2020-07-311-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | When BPF sk lookup invokes reuseport handling for the selected socket, it should ignore the fact that reuseport group can contain connected UDP sockets. With BPF sk lookup this is not relevant as we are not scoring sockets to find the best match, which might be a connected UDP socket. Fix it by unconditionally accepting the socket selected by reuseport. This fixes the following two failures reported by test_progs. # ./test_progs -t sk_lookup ... #73/14 UDP IPv4 redir and reuseport with conns:FAIL ... #73/20 UDP IPv6 redir and reuseport with conns:FAIL ... Fixes: a57066b1a019 ("Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net") Reported-by: Alexei Starovoitov <alexei.starovoitov@gmail.com> Signed-off-by: Jakub Sitnicki <jakub@cloudflare.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/bpf/20200726120228.1414348-1-jakub@cloudflare.com
* udp: Don't discard reuseport selection when group has connectionsJakub Sitnicki2020-07-261-3/+0
| | | | | | | | | | | | | | | | | | | When BPF socket lookup prog selects a socket that belongs to a reuseport group, and the reuseport group has connected sockets in it, the socket selected by reuseport will be discarded, and socket returned by BPF socket lookup will be used instead. Modify this behavior so that the socket selected by reuseport running after BPF socket lookup always gets used. Ignore the fact that the reuseport group might have connections because it is only relevant when scoring sockets during regular hashtable-based lookup. Fixes: 72f7e9440e9b ("udp: Run SK_LOOKUP BPF program on socket lookup") Fixes: 6d4201b1386b ("udp6: Run SK_LOOKUP BPF program on socket lookup") Signed-off-by: Jakub Sitnicki <jakub@cloudflare.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Kuniyuki Iwashima <kuniyu@amazon.co.jp> Link: https://lore.kernel.org/bpf/20200722161720.940831-2-jakub@cloudflare.com
* Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netDavid S. Miller2020-07-261-10/+11
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The UDP reuseport conflict was a little bit tricky. The net-next code, via bpf-next, extracted the reuseport handling into a helper so that the BPF sk lookup code could invoke it. At the same time, the logic for reuseport handling of unconnected sockets changed via commit efc6b6f6c3113e8b203b9debfb72d81e0f3dcace which changed the logic to carry on the reuseport result into the rest of the lookup loop if we do not return immediately. This requires moving the reuseport_has_conns() logic into the callers. While we are here, get rid of inline directives as they do not belong in foo.c files. The other changes were cases of more straightforward overlapping modifications. Signed-off-by: David S. Miller <davem@davemloft.net>
| * net: udp: Fix wrong clean up for IS_UDPLITE macroMiaohe Lin2020-07-221-1/+1
| | | | | | | | | | | | | | | | | | We can't use IS_UDPLITE to replace udp_sk->pcflag when UDPLITE_RECV_CC is checked. Fixes: b2bf1e2659b1 ("[UDP]: Clean up for IS_UDPLITE macro") Signed-off-by: Miaohe Lin <linmiaohe@huawei.com> Signed-off-by: David S. Miller <davem@davemloft.net>
| * udp: Improve load balancing for SO_REUSEPORT.Kuniyuki Iwashima2020-07-221-6/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently, SO_REUSEPORT does not work well if connected sockets are in a UDP reuseport group. Then reuseport_has_conns() returns true and the result of reuseport_select_sock() is discarded. Also, unconnected sockets have the same score, hence only does the first unconnected socket in udp_hslot always receive all packets sent to unconnected sockets. So, the result of reuseport_select_sock() should be used for load balancing. The noteworthy point is that the unconnected sockets placed after connected sockets in sock_reuseport.socks will receive more packets than others because of the algorithm in reuseport_select_sock(). index | connected | reciprocal_scale | result --------------------------------------------- 0 | no | 20% | 40% 1 | no | 20% | 20% 2 | yes | 20% | 0% 3 | no | 20% | 40% 4 | yes | 20% | 0% If most of the sockets are connected, this can be a problem, but it still works better than now. Fixes: acdcecc61285 ("udp: correct reuseport selection with connected sockets") CC: Willem de Bruijn <willemb@google.com> Reviewed-by: Benjamin Herrenschmidt <benh@amazon.com> Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.co.jp> Acked-by: Willem de Bruijn <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | net: pass a sockptr_t into ->setsockoptChristoph Hellwig2020-07-251-3/+3
| | | | | | | | | | | | | | | | | | | | | | Rework the remaining setsockopt code to pass a sockptr_t instead of a plain user pointer. This removes the last remaining set_fs(KERNEL_DS) outside of architecture specific code. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Stefan Schmidt <stefan@datenfreihafen.org> [ieee802154] Acked-by: Matthieu Baerts <matthieu.baerts@tessares.net> Signed-off-by: David S. Miller <davem@davemloft.net>
* | net/udp: switch udp_lib_setsockopt to sockptr_tChristoph Hellwig2020-07-251-1/+2
| | | | | | | | | | | | | | | | Pass a sockptr_t to prepare for set_fs-less handling of the kernel pointer from bpf-cgroup. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: David S. Miller <davem@davemloft.net>
* | Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-nextDavid S. Miller2020-07-221-20/+77
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Alexei Starovoitov says: ==================== pull-request: bpf-next 2020-07-21 The following pull-request contains BPF updates for your *net-next* tree. We've added 46 non-merge commits during the last 6 day(s) which contain a total of 68 files changed, 4929 insertions(+), 526 deletions(-). The main changes are: 1) Run BPF program on socket lookup, from Jakub. 2) Introduce cpumap, from Lorenzo. 3) s390 JIT fixes, from Ilya. 4) teach riscv JIT to emit compressed insns, from Luke. 5) use build time computed BTF ids in bpf iter, from Yonghong. ==================== Purely independent overlapping changes in both filter.h and xdp.h Signed-off-by: David S. Miller <davem@davemloft.net>
| * | udp6: Run SK_LOOKUP BPF program on socket lookupJakub Sitnicki2020-07-181-9/+51
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Same as for udp4, let BPF program override the socket lookup result, by selecting a receiving socket of its choice or failing the lookup, if no connected UDP socket matched packet 4-tuple. Suggested-by: Marek Majkowski <marek@cloudflare.com> Signed-off-by: Jakub Sitnicki <jakub@cloudflare.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Andrii Nakryiko <andriin@fb.com> Link: https://lore.kernel.org/bpf/20200717103536.397595-11-jakub@cloudflare.com
| * | udp6: Extract helper for selecting socket from reuseport groupJakub Sitnicki2020-07-181-11/+26
| | | | | | | | | | | | | | | | | | | | | | | | | | | Prepare for calling into reuseport from __udp6_lib_lookup as well. Signed-off-by: Jakub Sitnicki <jakub@cloudflare.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Andrii Nakryiko <andriin@fb.com> Link: https://lore.kernel.org/bpf/20200717103536.397595-10-jakub@cloudflare.com
* | | net/ipv6: remove compat_ipv6_{get,set}sockoptChristoph Hellwig2020-07-201-25/+0
|/ / | | | | | | | | | | | | | | | | Handle the few cases that need special treatment in-line using in_compat_syscall(). This also removes all the now unused compat_{get,set}sockopt methods. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: David S. Miller <davem@davemloft.net>
* / net: ipv6: kerneldoc fixesAndrew Lunn2020-07-141-0/+3
|/ | | | | | | | | Simple fixes which require no deep knowledge of the code. Cc: Alexey Kuznetsov <kuznet@ms2.inr.ac.ru> Cc: Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org> Signed-off-by: Andrew Lunn <andrew@lunn.ch> Signed-off-by: David S. Miller <davem@davemloft.net>
* net: Track socket refcounts in skb_steal_sock()Joe Stringer2020-03-301-3/+6
| | | | | | | | | | | Refactor the UDP/TCP handlers slightly to allow skb_steal_sock() to make the determination of whether the socket is reference counted in the case where it is prefetched by earlier logic such as early_demux. Signed-off-by: Joe Stringer <joe@wand.net.nz> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Martin KaFai Lau <kafai@fb.com> Link: https://lore.kernel.org/bpf/20200329225342.16317-3-joe@wand.net.nz
* net: udp: use skb_list_walk_safe helper for gso segmentsJason A. Donenfeld2020-01-141-2/+1
| | | | | | | | | This is a straight-forward conversion case for the new function, iterating over the return value from udp_rcv_segment, which actually is a wrapper around skb_gso_segment. Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* net: annotate accesses to sk->sk_incoming_cpuEric Dumazet2019-10-301-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This socket field can be read and written by concurrent cpus. Use READ_ONCE() and WRITE_ONCE() annotations to document this, and avoid some compiler 'optimizations'. KCSAN reported : BUG: KCSAN: data-race in tcp_v4_rcv / tcp_v4_rcv write to 0xffff88812220763c of 4 bytes by interrupt on cpu 0: sk_incoming_cpu_update include/net/sock.h:953 [inline] tcp_v4_rcv+0x1b3c/0x1bb0 net/ipv4/tcp_ipv4.c:1934 ip_protocol_deliver_rcu+0x4d/0x420 net/ipv4/ip_input.c:204 ip_local_deliver_finish+0x110/0x140 net/ipv4/ip_input.c:231 NF_HOOK include/linux/netfilter.h:305 [inline] NF_HOOK include/linux/netfilter.h:299 [inline] ip_local_deliver+0x133/0x210 net/ipv4/ip_input.c:252 dst_input include/net/dst.h:442 [inline] ip_rcv_finish+0x121/0x160 net/ipv4/ip_input.c:413 NF_HOOK include/linux/netfilter.h:305 [inline] NF_HOOK include/linux/netfilter.h:299 [inline] ip_rcv+0x18f/0x1a0 net/ipv4/ip_input.c:523 __netif_receive_skb_one_core+0xa7/0xe0 net/core/dev.c:5010 __netif_receive_skb+0x37/0xf0 net/core/dev.c:5124 process_backlog+0x1d3/0x420 net/core/dev.c:5955 napi_poll net/core/dev.c:6392 [inline] net_rx_action+0x3ae/0xa90 net/core/dev.c:6460 __do_softirq+0x115/0x33f kernel/softirq.c:292 do_softirq_own_stack+0x2a/0x40 arch/x86/entry/entry_64.S:1082 do_softirq.part.0+0x6b/0x80 kernel/softirq.c:337 do_softirq kernel/softirq.c:329 [inline] __local_bh_enable_ip+0x76/0x80 kernel/softirq.c:189 read to 0xffff88812220763c of 4 bytes by interrupt on cpu 1: sk_incoming_cpu_update include/net/sock.h:952 [inline] tcp_v4_rcv+0x181a/0x1bb0 net/ipv4/tcp_ipv4.c:1934 ip_protocol_deliver_rcu+0x4d/0x420 net/ipv4/ip_input.c:204 ip_local_deliver_finish+0x110/0x140 net/ipv4/ip_input.c:231 NF_HOOK include/linux/netfilter.h:305 [inline] NF_HOOK include/linux/netfilter.h:299 [inline] ip_local_deliver+0x133/0x210 net/ipv4/ip_input.c:252 dst_input include/net/dst.h:442 [inline] ip_rcv_finish+0x121/0x160 net/ipv4/ip_input.c:413 NF_HOOK include/linux/netfilter.h:305 [inline] NF_HOOK include/linux/netfilter.h:299 [inline] ip_rcv+0x18f/0x1a0 net/ipv4/ip_input.c:523 __netif_receive_skb_one_core+0xa7/0xe0 net/core/dev.c:5010 __netif_receive_skb+0x37/0xf0 net/core/dev.c:5124 process_backlog+0x1d3/0x420 net/core/dev.c:5955 napi_poll net/core/dev.c:6392 [inline] net_rx_action+0x3ae/0xa90 net/core/dev.c:6460 __do_softirq+0x115/0x33f kernel/softirq.c:292 run_ksoftirqd+0x46/0x60 kernel/softirq.c:603 smpboot_thread_fn+0x37d/0x4a0 kernel/smpboot.c:165 Reported by Kernel Concurrency Sanitizer on: CPU: 1 PID: 16 Comm: ksoftirqd/1 Not tainted 5.4.0-rc3+ #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* udp: only do GSO if # of segs > 1Josh Hunt2019-10-031-4/+7
| | | | | | | | | | | | | | | | | | | Prior to this change an application sending <= 1MSS worth of data and enabling UDP GSO would fail if the system had SW GSO enabled, but the same send would succeed if HW GSO offload is enabled. In addition to this inconsistency the error in the SW GSO case does not get back to the application if sending out of a real device so the user is unaware of this failure. With this change we only perform GSO if the # of segments is > 1 even if the application has enabled segmentation. I've also updated the relevant udpgso selftests. Fixes: bec1f6f69736 ("udp: generate gso with UDP_SEGMENT") Signed-off-by: Josh Hunt <johunt@akamai.com> Reviewed-by: Willem de Bruijn <willemb@google.com> Reviewed-by: Alexander Duyck <alexander.h.duyck@linux.intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* udp: fix gso_segs calculationsJosh Hunt2019-10-031-0/+2
| | | | | | | | | | | | | Commit dfec0ee22c0a ("udp: Record gso_segs when supporting UDP segmentation offload") added gso_segs calculation, but incorrectly got sizeof() the pointer and not the underlying data type. In addition let's fix the v6 case. Fixes: bec1f6f69736 ("udp: generate gso with UDP_SEGMENT") Fixes: dfec0ee22c0a ("udp: Record gso_segs when supporting UDP segmentation offload") Signed-off-by: Josh Hunt <johunt@akamai.com> Reviewed-by: Alexander Duyck <alexander.h.duyck@linux.intel.com> Acked-by: Willem de Bruijn <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* Merge ra.kernel.org:/pub/scm/linux/kernel/git/netdev/netDavid S. Miller2019-09-171-2/+3
|\ | | | | | | | | | | Pull in bug fixes from 'net' tree for the merge window. Signed-off-by: David S. Miller <davem@davemloft.net>
| * udp: correct reuseport selection with connected socketsWillem de Bruijn2019-09-161-2/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | UDP reuseport groups can hold a mix unconnected and connected sockets. Ensure that connections only receive all traffic to their 4-tuple. Fast reuseport returns on the first reuseport match on the assumption that all matches are equal. Only if connections are present, return to the previous behavior of scoring all sockets. Record if connections are present and if so (1) treat such connected sockets as an independent match from the group, (2) only return 2-tuple matches from reuseport and (3) do not return on the first 2-tuple reuseport match to allow for a higher scoring match later. New field has_conns is set without locks. No other fields in the bitmap are modified at runtime and the field is only ever set unconditionally, so an RMW cannot miss a change. Fixes: e32ea7e74727 ("soreuseport: fast reuseport UDP socket selection") Link: http://lkml.kernel.org/r/CA+FuTSfRP09aJNYRt04SS6qj22ViiOEWaWmLAwX0psk8-PGNxw@mail.gmail.com Signed-off-by: Willem de Bruijn <willemb@google.com> Acked-by: Paolo Abeni <pabeni@redhat.com> Acked-by: Craig Gallek <kraig@google.com> Signed-off-by: Willem de Bruijn <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | ip: support SO_MARK cmsgWillem de Bruijn2019-09-131-1/+2
|/ | | | | | | | | | | | | | | | | | | | | Enable setting skb->mark for UDP and RAW sockets using cmsg. This is analogous to existing support for TOS, TTL, txtime, etc. Packet sockets already support this as of commit c7d39e32632e ("packet: support per-packet fwmark for af_packet sendmsg"). Similar to other fields, implement by 1. initialize the sockcm_cookie.mark from socket option sk_mark 2. optionally overwrite this in ip_cmsg_send/ip6_datagram_send_ctl 3. initialize inet_cork.mark from sockcm_cookie.mark 4. initialize each (usually just one) skb->mark from inet_cork.mark Step 1 is handled in one location for most protocols by ipcm_init_sk as of commit 351782067b6b ("ipv4: ipcm_cookie initializers"). Signed-off-by: Willem de Bruijn <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* ipv6: elide flowlabel check if no exclusive leases existWillem de Bruijn2019-07-091-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Processes can request ipv6 flowlabels with cmsg IPV6_FLOWINFO. If not set, by default an autogenerated flowlabel is selected. Explicit flowlabels require a control operation per label plus a datapath check on every connection (every datagram if unconnected). This is particularly expensive on unconnected sockets multiplexing many flows, such as QUIC. In the common case, where no lease is exclusive, the check can be safely elided, as both lease request and check trivially succeed. Indeed, autoflowlabel does the same even with exclusive leases. Elide the check if no process has requested an exclusive lease. fl6_sock_lookup previously returns either a reference to a lease or NULL to denote failure. Modify to return a real error and update all callers. On return NULL, they can use the label and will elide the atomic_dec in fl6_sock_release. This is an optimization. Robust applications still have to revert to requesting leases if the fast path fails due to an exclusive lease. Changes RFC->v1: - use static_key_false_deferred to rate limit jump label operations - call static_key_deferred_flush to stop timers on exit - move decrement out of RCU context - defer optimization also if opt data is associated with a lease - updated all fp6_sock_lookup callers, not just udp Signed-off-by: Willem de Bruijn <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* net: remove unused parameter from skb_checksum_try_convertLi RongQing2019-07-061-2/+1
| | | | | | | the check parameter is never used Signed-off-by: Li RongQing <lirongqing@baidu.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller2019-06-181-2/+6
|\ | | | | | | | | | | | | Honestly all the conflicts were simple overlapping changes, nothing really interesting to report. Signed-off-by: David S. Miller <davem@davemloft.net>
| * Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpfDavid S. Miller2019-06-071-2/+6
| |\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Daniel Borkmann says: ==================== pull-request: bpf 2019-06-07 The following pull-request contains BPF updates for your *net* tree. The main changes are: 1) Fix several bugs in riscv64 JIT code emission which forgot to clear high 32-bits for alu32 ops, from Björn and Luke with selftests covering all relevant BPF alu ops from Björn and Jiong. 2) Two fixes for UDP BPF reuseport that avoid calling the program in case of __udp6_lib_err and UDP GRO which broke reuseport_select_sock() assumption that skb->data is pointing to transport header, from Martin. 3) Two fixes for BPF sockmap: a use-after-free from sleep in psock's backlog workqueue, and a missing restore of sk_write_space when psock gets dropped, from Jakub and John. 4) Fix unconnected UDP sendmsg hook API which is insufficient as-is since it breaks standard applications like DNS if reverse NAT is not performed upon receive, from Daniel. 5) Fix an out-of-bounds read in __bpf_skc_lookup which in case of AF_INET6 fails to verify that the length of the tuple is long enough, from Lorenz. 6) Fix libbpf's libbpf__probe_raw_btf to return an fd instead of 0/1 (for {un,}successful probe) as that is expected to be propagated as an fd to load_sk_storage_btf() and thus closing the wrong descriptor otherwise, from Michal. 7) Fix bpftool's JSON output for the case when a lookup fails, from Krzesimir. 8) Minor misc fixes in docs, samples and selftests, from various others. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
| | * bpf: fix unconnected udp hooksDaniel Borkmann2019-06-071-0/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Intention of cgroup bind/connect/sendmsg BPF hooks is to act transparently to applications as also stated in original motivation in 7828f20e3779 ("Merge branch 'bpf-cgroup-bind-connect'"). When recently integrating the latter two hooks into Cilium to enable host based load-balancing with Kubernetes, I ran into the issue that pods couldn't start up as DNS got broken. Kubernetes typically sets up DNS as a service and is thus subject to load-balancing. Upon further debugging, it turns out that the cgroupv2 sendmsg BPF hooks API is currently insufficient and thus not usable as-is for standard applications shipped with most distros. To break down the issue we ran into with a simple example: # cat /etc/resolv.conf nameserver 147.75.207.207 nameserver 147.75.207.208 For the purpose of a simple test, we set up above IPs as service IPs and transparently redirect traffic to a different DNS backend server for that node: # cilium service list ID Frontend Backend 1 147.75.207.207:53 1 => 8.8.8.8:53 2 147.75.207.208:53 1 => 8.8.8.8:53 The attached BPF program is basically selecting one of the backends if the service IP/port matches on the cgroup hook. DNS breaks here, because the hooks are not transparent enough to applications which have built-in msg_name address checks: # nslookup 1.1.1.1 ;; reply from unexpected source: 8.8.8.8#53, expected 147.75.207.207#53 ;; reply from unexpected source: 8.8.8.8#53, expected 147.75.207.208#53 ;; reply from unexpected source: 8.8.8.8#53, expected 147.75.207.207#53 [...] ;; connection timed out; no servers could be reached # dig 1.1.1.1 ;; reply from unexpected source: 8.8.8.8#53, expected 147.75.207.207#53 ;; reply from unexpected source: 8.8.8.8#53, expected 147.75.207.208#53 ;; reply from unexpected source: 8.8.8.8#53, expected 147.75.207.207#53 [...] ; <<>> DiG 9.11.3-1ubuntu1.7-Ubuntu <<>> 1.1.1.1 ;; global options: +cmd ;; connection timed out; no servers could be reached For comparison, if none of the service IPs is used, and we tell nslookup to use 8.8.8.8 directly it works just fine, of course: # nslookup 1.1.1.1 8.8.8.8 1.1.1.1.in-addr.arpa name = one.one.one.one. In order to fix this and thus act more transparent to the application, this needs reverse translation on recvmsg() side. A minimal fix for this API is to add similar recvmsg() hooks behind the BPF cgroups static key such that the program can track state and replace the current sockaddr_in{,6} with the original service IP. From BPF side, this basically tracks the service tuple plus socket cookie in an LRU map where the reverse NAT can then be retrieved via map value as one example. Side-note: the BPF cgroups static key should be converted to a per-hook static key in future. Same example after this fix: # cilium service list ID Frontend Backend 1 147.75.207.207:53 1 => 8.8.8.8:53 2 147.75.207.208:53 1 => 8.8.8.8:53 Lookups work fine now: # nslookup 1.1.1.1 1.1.1.1.in-addr.arpa name = one.one.one.one. Authoritative answers can be found from: # dig 1.1.1.1 ; <<>> DiG 9.11.3-1ubuntu1.7-Ubuntu <<>> 1.1.1.1 ;; global options: +cmd ;; Got answer: ;; ->>HEADER<<- opcode: QUERY, status: NXDOMAIN, id: 51550 ;; flags: qr rd ra ad; QUERY: 1, ANSWER: 0, AUTHORITY: 1, ADDITIONAL: 1 ;; OPT PSEUDOSECTION: ; EDNS: version: 0, flags:; udp: 512 ;; QUESTION SECTION: ;1.1.1.1. IN A ;; AUTHORITY SECTION: . 23426 IN SOA a.root-servers.net. nstld.verisign-grs.com. 2019052001 1800 900 604800 86400 ;; Query time: 17 msec ;; SERVER: 147.75.207.207#53(147.75.207.207) ;; WHEN: Tue May 21 12:59:38 UTC 2019 ;; MSG SIZE rcvd: 111 And from an actual packet level it shows that we're using the back end server when talking via 147.75.207.20{7,8} front end: # tcpdump -i any udp [...] 12:59:52.698732 IP foo.42011 > google-public-dns-a.google.com.domain: 18803+ PTR? 1.1.1.1.in-addr.arpa. (38) 12:59:52.698735 IP foo.42011 > google-public-dns-a.google.com.domain: 18803+ PTR? 1.1.1.1.in-addr.arpa. (38) 12:59:52.701208 IP google-public-dns-a.google.com.domain > foo.42011: 18803 1/0/0 PTR one.one.one.one. (67) 12:59:52.701208 IP google-public-dns-a.google.com.domain > foo.42011: 18803 1/0/0 PTR one.one.one.one. (67) [...] In order to be flexible and to have same semantics as in sendmsg BPF programs, we only allow return codes in [1,1] range. In the sendmsg case the program is called if msg->msg_name is present which can be the case in both, connected and unconnected UDP. The former only relies on the sockaddr_in{,6} passed via connect(2) if passed msg->msg_name was NULL. Therefore, on recvmsg side, we act in similar way to call into the BPF program whenever a non-NULL msg->msg_name was passed independent of sk->sk_state being TCP_ESTABLISHED or not. Note that for TCP case, the msg->msg_name is ignored in the regular recvmsg path and therefore not relevant. For the case of ip{,v6}_recv_error() paths, picked up via MSG_ERRQUEUE, the hook is not called. This is intentional as it aligns with the same semantics as in case of TCP cgroup BPF hooks right now. This might be better addressed in future through a different bpf_attach_type such that this case can be distinguished from the regular recvmsg paths, for example. Fixes: 1cedee13d25a ("bpf: Hooks for sys_sendmsg") Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Andrey Ignatov <rdna@fb.com> Acked-by: Martin KaFai Lau <kafai@fb.com> Acked-by: Martynas Pumputis <m@lambda.lt> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
| | * bpf: udp: Avoid calling reuseport's bpf_prog from udp_groMartin KaFai Lau2019-06-031-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When the commit a6024562ffd7 ("udp: Add GRO functions to UDP socket") added udp[46]_lib_lookup_skb to the udp_gro code path, it broke the reuseport_select_sock() assumption that skb->data is pointing to the transport header. This patch follows an earlier __udp6_lib_err() fix by passing a NULL skb to avoid calling the reuseport's bpf_prog. Fixes: a6024562ffd7 ("udp: Add GRO functions to UDP socket") Cc: Tom Herbert <tom@herbertland.com> Signed-off-by: Martin KaFai Lau <kafai@fb.com> Acked-by: Song Liu <songliubraving@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
| | * bpf: udp: ipv6: Avoid running reuseport's bpf_prog from __udp6_lib_errMartin KaFai Lau2019-06-031-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | __udp6_lib_err() may be called when handling icmpv6 message. For example, the icmpv6 toobig(type=2). __udp6_lib_lookup() is then called which may call reuseport_select_sock(). reuseport_select_sock() will call into a bpf_prog (if there is one). reuseport_select_sock() is expecting the skb->data pointing to the transport header (udphdr in this case). For example, run_bpf_filter() is pulling the transport header. However, in the __udp6_lib_err() path, the skb->data is pointing to the ipv6hdr instead of the udphdr. One option is to pull and push the ipv6hdr in __udp6_lib_err(). Instead of doing this, this patch follows how the original commit 538950a1b752 ("soreuseport: setsockopt SO_ATTACH_REUSEPORT_[CE]BPF") was done in IPv4, which has passed a NULL skb pointer to reuseport_select_sock(). Fixes: 538950a1b752 ("soreuseport: setsockopt SO_ATTACH_REUSEPORT_[CE]BPF") Cc: Craig Gallek <kraig@google.com> Signed-off-by: Martin KaFai Lau <kafai@fb.com> Acked-by: Song Liu <songliubraving@fb.com> Acked-by: Craig Gallek <kraig@google.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
* | | udp: Remove unused variable/function (exact_dif)Tim Beale2019-06-151-11/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This was originally passed through to the VRF logic in compute_score(). But that logic has now been replaced by udp_sk_bound_dev_eq() and so this code is no longer used or needed. Signed-off-by: Tim Beale <timbeale@catalyst.net.nz> Reviewed-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | | udp: Remove unused parameter (exact_dif)Tim Beale2019-06-151-7/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Originally this was used by the VRF logic in compute_score(), but that was later replaced by udp_sk_bound_dev_eq() and the parameter became unused. Note this change adds an 'unused variable' compiler warning that will be removed in the next patch (I've split the removal in two to make review slightly easier). Signed-off-by: Tim Beale <timbeale@catalyst.net.nz> Reviewed-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | | Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller2019-06-071-5/+1
|\| | | | | | | | | | | | | | | | | | | | Some ISDN files that got removed in net-next had some changes done in mainline, take the removals. Signed-off-by: David S. Miller <davem@davemloft.net>
| * | treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152Thomas Gleixner2019-05-301-5/+1
| |/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license as published by the free software foundation either version 2 of the license or at your option any later version extracted by the scancode license scanner the SPDX license identifier GPL-2.0-or-later has been chosen to replace the boilerplate/reference in 3029 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Allison Randal <allison@lohutok.net> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* / net: ipv6: drop unneeded likely() call around IS_ERR()Enrico Weigelt2019-06-061-1/+1
|/ | | | | | | | IS_ERR() already calls unlikely(), so this extra unlikely() call around IS_ERR() is not needed. Signed-off-by: Enrico Weigelt <info@metux.net> Signed-off-by: David S. Miller <davem@davemloft.net>
* net: use indirect calls helpers at early demux stagePaolo Abeni2019-05-051-1/+1
| | | | | | | | So that we avoid another indirect call per RX packet, if early demux is enabled. Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* net: use indirect calls helpers for L3 handler hooksPaolo Abeni2019-05-051-1/+2
| | | | | | | | So that we avoid another indirect call per RX packet in the common case. Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller2019-04-171-0/+2
|\ | | | | | | | | | | Conflict resolution of af_smc.c from Stephen Rothwell. Signed-off-by: David S. Miller <davem@davemloft.net>
| * udpv6: Check address length before reading address familyTetsuo Handa2019-04-121-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | KMSAN will complain if valid address length passed to udpv6_pre_connect() is shorter than sizeof("struct sockaddr"->sa_family) bytes. (This patch is bogus if it is guaranteed that udpv6_pre_connect() is always called after checking "struct sockaddr"->sa_family. In that case, we want a comment why we don't need to check valid address length here.) Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Acked-by: Song Liu <songliubraving@fb.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | datagram: remove rendundant 'peeked' argumentPaolo Abeni2019-04-081-6/+4
|/ | | | | | | | | | | | | | After commit a297569fe00a ("net/udp: do not touch skb->peeked unless really needed") the 'peeked' argument of __skb_try_recv_datagram() and friends is always equal to !!'flags & MSG_PEEK'. Since such argument is really a boolean info, and the callers have already 'flags & MSG_PEEK' handy, we can remove it and clean-up the code a bit. Signed-off-by: Paolo Abeni <pabeni@redhat.com> Acked-by: Willem de Bruijn <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* udpv6: fix possible user after free in error handlerPaolo Abeni2019-02-231-4/+6
| | | | | | | | | | | | | Before derefencing the encap pointer, commit e7cc082455cb ("udp: Support for error handlers of tunnels with arbitrary destination port") checks for a NULL value, but the two fetch operation can race with removal. Fix the above using a single access. Also fix a couple of type annotations, to make sparse happy. Fixes: e7cc082455cb ("udp: Support for error handlers of tunnels with arbitrary destination port") Signed-off-by: Paolo Abeni <pabeni@redhat.com> Acked-by: Stefano Brivio <sbrivio@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* udpv6: add the required annotation to mib typePaolo Abeni2019-02-231-1/+1
| | | | | | | | | | In commit 029a37434880 ("udp6: cleanup stats accounting in recvmsg()") I forgot to add the percpu annotation for the mib pointer. Add it, and make sparse happy. Fixes: 029a37434880 ("udp6: cleanup stats accounting in recvmsg()") Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* udp6: add missing rehash callback to udpliteAlexey Kodanev2019-01-181-1/+1
| | | | | | | | | | | | | | | | | After commit 23b0269e58ae ("net: udp6: prefer listeners bound to an address"), UDP-Lite only works when specifying a local address for the sockets. This is related to the problem addressed in the commit 719f835853a9 ("udp: add rehash on connect()"). Moreover, __udp6_lib_lookup() now looks for a socket immediately in the secondary hash table. And this issue was found with LTP/network tests as well. Fixes: 23b0269e58ae ("net: udp6: prefer listeners bound to an address") Signed-off-by: Alexey Kodanev <alexey.kodanev@oracle.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* udp: with udp_segment release on error pathWillem de Bruijn2019-01-171-4/+12
| | | | | | | | | | Failure __ip_append_data triggers udp_flush_pending_frames, but these tests happen later. The skb must be freed directly. Fixes: bec1f6f697362 ("udp: generate gso with UDP_SEGMENT") Reported-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Willem de Bruijn <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>