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2017-01-27net: adjust skb->truesize in pskb_expand_head()Eric Dumazet1-1/+1
Slava Shwartsman reported a warning in skb_try_coalesce(), when we detect skb->truesize is completely wrong. In his case, issue came from IPv6 reassembly coping with malicious datagrams, that forced various pskb_may_pull() to reallocate a bigger skb->head than the one allocated by NIC driver before entering GRO layer. Current code does not change skb->truesize, leaving this burden to callers if they care enough. Blindly changing skb->truesize in pskb_expand_head() is not easy, as some producers might track skb->truesize, for example in xmit path for back pressure feedback (sk->sk_wmem_alloc) We can detect the cases where it should be safe to change skb->truesize : 1) skb is not attached to a socket. 2) If it is attached to a socket, destructor is sock_edemux() My audit gave only two callers doing their own skb->truesize manipulation. I had to remove skb parameter in sock_edemux macro when CONFIG_INET is not set to avoid a compile error. Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Slava Shwartsman <slavash@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-01-20sock: use hlist_entry_safeGeliang Tang1-2/+1
Use hlist_entry_safe() instead of open-coding it. Signed-off-by: Geliang Tang <geliangtang@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-01-09smc: netlink interface for SMC socketsUrsula Braun1-0/+3
Support for SMC socket monitoring via netlink sockets of protocol NETLINK_SOCK_DIAG. Signed-off-by: Ursula Braun <ubraun@linux.vnet.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-01-09net: introduce keepalive function in struct protoUrsula Braun1-0/+1
Direct call of tcp_set_keepalive() function from protocol-agnostic sock_setsockopt() function in net/core/sock.c violates network layering. And newly introduced protocol (SMC-R) will need its own keepalive function. Therefore, add "keepalive" function pointer to "struct proto", and call it from sock_setsockopt() via this pointer. Signed-off-by: Ursula Braun <ubraun@linux.vnet.ibm.com> Reviewed-by: Utz Bacher <utz.bacher@de.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-12-25ktime: Get rid of the unionThomas Gleixner1-2/+2
ktime is a union because the initial implementation stored the time in scalar nanoseconds on 64 bit machine and in a endianess optimized timespec variant for 32bit machines. The Y2038 cleanup removed the timespec variant and switched everything to scalar nanoseconds. The union remained, but become completely pointless. Get rid of the union and just keep ktime_t as simple typedef of type s64. The conversion was done with coccinelle and some manual mopping up. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org>
2016-12-16Merge branch 'for-linus' of ↵Linus Torvalds1-3/+3
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull vfs updates from Al Viro: - more ->d_init() stuff (work.dcache) - pathname resolution cleanups (work.namei) - a few missing iov_iter primitives - copy_from_iter_full() and friends. Either copy the full requested amount, advance the iterator and return true, or fail, return false and do _not_ advance the iterator. Quite a few open-coded callers converted (and became more readable and harder to fuck up that way) (work.iov_iter) - several assorted patches, the big one being logfs removal * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: logfs: remove from tree vfs: fix put_compat_statfs64() does not handle errors namei: fold should_follow_link() with the step into not-followed link namei: pass both WALK_GET and WALK_MORE to should_follow_link() namei: invert WALK_PUT logics namei: shift interpretation of LOOKUP_FOLLOW inside should_follow_link() namei: saner calling conventions for mountpoint_last() namei.c: get rid of user_path_parent() switch getfrag callbacks to ..._full() primitives make skb_add_data,{_nocache}() and skb_copy_to_page_nocache() advance only on success [iov_iter] new primitives - copy_from_iter_full() and friends don't open-code file_inode() ceph: switch to use of ->d_init() ceph: unify dentry_operations instances lustre: switch to use of ->d_init()
2016-12-08net: do not read sk_drops if application does not careEric Dumazet1-1/+2
sk_drops can be an often written field, do not read it unless application showed interest. Note that sk_drops can be read via inet_diag, so applications can avoid getting this info from every received packet. In the future, 'reading' sk_drops might require folding per node or per cpu fields, and thus become even more expensive than today. Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Paolo Abeni <pabeni@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-12-08net: rfs: add a jump labelEric Dumazet1-11/+14
RFS is not commonly used, so add a jump label to avoid some conditionals in fast path. Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Paolo Abeni <pabeni@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-12-07net: sock_rps_record_flow() is for connected socketsEric Dumazet1-1/+11
Paolo noticed a cache line miss in UDP recvmsg() to access sk_rxhash, sharing a cache line with sk_drops. sk_drops might be heavily incremented by cpus handling a flood targeting this socket. We might place sk_drops on a separate cache line, but lets try to avoid wasting 64 bytes per socket just for this, since we have other bottlenecks to take care of. sock_rps_record_flow() should only access sk_rxhash for connected flows. Testing sk_state for TCP_ESTABLISHED covers most of the cases for connected sockets, for a zero cost, since system calls using sock_rps_record_flow() also access sk->sk_prot which is on the same cache line. A follow up patch will provide a static_key (Jump Label) since most hosts do not even use RFS. Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Paolo Abeni <pabeni@redhat.com> Acked-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-12-05make skb_add_data,{_nocache}() and skb_copy_to_page_nocache() advance only ↵Al Viro1-3/+3
on success Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-12-05net: reorganize struct sock for better data localityEric Dumazet1-24/+27
Group fields used in TX path, and keep some cache lines mostly read to permit sharing among cpus. Gained two 4 bytes holes on 64bit arches. Added a place holder for tcp tsq_flags, next to sk_wmem_alloc to speed up tcp_wfree() in the following patch. I have not added ____cacheline_aligned_in_smp, this might be done later. I prefer doing this once inet and tcp/udp sockets reorg is also done. Tested with both TCP and UDP. UDP receiver performance under flood increased by ~20 % : Accessing sk_filter/sk_wq/sk_napi_id no longer stalls because sk_drops was moved away from a critical cache line, now mostly read and shared. /* --- cacheline 4 boundary (256 bytes) --- */ unsigned int sk_napi_id; /* 0x100 0x4 */ int sk_rcvbuf; /* 0x104 0x4 */ struct sk_filter * sk_filter; /* 0x108 0x8 */ union { struct socket_wq * sk_wq; /* 0x8 */ struct socket_wq * sk_wq_raw; /* 0x8 */ }; /* 0x110 0x8 */ struct xfrm_policy * sk_policy[2]; /* 0x118 0x10 */ struct dst_entry * sk_rx_dst; /* 0x128 0x8 */ struct dst_entry * sk_dst_cache; /* 0x130 0x8 */ atomic_t sk_omem_alloc; /* 0x138 0x4 */ int sk_sndbuf; /* 0x13c 0x4 */ /* --- cacheline 5 boundary (320 bytes) --- */ int sk_wmem_queued; /* 0x140 0x4 */ atomic_t sk_wmem_alloc; /* 0x144 0x4 */ long unsigned int sk_tsq_flags; /* 0x148 0x8 */ struct sk_buff * sk_send_head; /* 0x150 0x8 */ struct sk_buff_head sk_write_queue; /* 0x158 0x18 */ __s32 sk_peek_off; /* 0x170 0x4 */ int sk_write_pending; /* 0x174 0x4 */ long int sk_sndtimeo; /* 0x178 0x8 */ Signed-off-by: Eric Dumazet <edumazet@google.com> Tested-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-12-02bpf: Add support for reading socket family, type, protocolDavid Ahern1-0/+15
Add socket family, type and protocol to bpf_sock allowing bpf programs read-only access. Add __sk_flags_offset[0] to struct sock before the bitfield to programmtically determine the offset of the unsigned int containing protocol and type. Signed-off-by: David Ahern <dsa@cumulusnetworks.com> Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-15Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller1-2/+2
Several cases of bug fixes in 'net' overlapping other changes in 'net-next-. Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-14net: fix sleeping for sk_wait_event()WANG Cong1-3/+5
Similar to commit 14135f30e33c ("inet: fix sleeping inside inet_wait_for_connect()"), sk_wait_event() needs to fix too, because release_sock() is blocking, it changes the process state back to running after sleep, which breaks the previous prepare_to_wait(). Switch to the new wait API. Cc: Eric Dumazet <eric.dumazet@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-04net: core: Add a UID field to struct sock.Lorenzo Colitti1-0/+7
Protocol sockets (struct sock) don't have UIDs, but most of the time, they map 1:1 to userspace sockets (struct socket) which do. Various operations such as the iptables xt_owner match need access to the "UID of a socket", and do so by following the backpointer to the struct socket. This involves taking sk_callback_lock and doesn't work when there is no socket because userspace has already called close(). Simplify this by adding a sk_uid field to struct sock whose value matches the UID of the corresponding struct socket. The semantics are as follows: 1. Whenever sk_socket is non-null: sk_uid is the same as the UID in sk_socket, i.e., matches the return value of sock_i_uid. Specifically, the UID is set when userspace calls socket(), fchown(), or accept(). 2. When sk_socket is NULL, sk_uid is defined as follows: - For a socket that no longer has a sk_socket because userspace has called close(): the previous UID. - For a cloned socket (e.g., an incoming connection that is established but on which userspace has not yet called accept): the UID of the socket it was cloned from. - For a socket that has never had an sk_socket: UID 0 inside the user namespace corresponding to the network namespace the socket belongs to. Kernel sockets created by sock_create_kern are a special case of #1 and sk_uid is the user that created them. For kernel sockets created at network namespace creation time, such as the per-processor ICMP and TCP sockets, this is the user that created the network namespace. Signed-off-by: Lorenzo Colitti <lorenzo@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-03dccp: do not release listeners too soonEric Dumazet1-2/+2
Andrey Konovalov reported following error while fuzzing with syzkaller : IPv4: Attempt to release alive inet socket ffff880068e98940 kasan: CONFIG_KASAN_INLINE enabled kasan: GPF could be caused by NULL-ptr deref or user memory access general protection fault: 0000 [#1] SMP KASAN Modules linked in: CPU: 1 PID: 3905 Comm: a.out Not tainted 4.9.0-rc3+ #333 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011 task: ffff88006b9e0000 task.stack: ffff880068770000 RIP: 0010:[<ffffffff819ead5f>] [<ffffffff819ead5f>] selinux_socket_sock_rcv_skb+0xff/0x6a0 security/selinux/hooks.c:4639 RSP: 0018:ffff8800687771c8 EFLAGS: 00010202 RAX: ffff88006b9e0000 RBX: 1ffff1000d0eee3f RCX: 1ffff1000d1d312a RDX: 1ffff1000d1d31a6 RSI: dffffc0000000000 RDI: 0000000000000010 RBP: ffff880068777360 R08: 0000000000000000 R09: 0000000000000002 R10: dffffc0000000000 R11: 0000000000000006 R12: ffff880068e98940 R13: 0000000000000002 R14: ffff880068777338 R15: 0000000000000000 FS: 00007f00ff760700(0000) GS:ffff88006cd00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000020008000 CR3: 000000006a308000 CR4: 00000000000006e0 Stack: ffff8800687771e0 ffffffff812508a5 ffff8800686f3168 0000000000000007 ffff88006ac8cdfc ffff8800665ea500 0000000041b58ab3 ffffffff847b5480 ffffffff819eac60 ffff88006b9e0860 ffff88006b9e0868 ffff88006b9e07f0 Call Trace: [<ffffffff819c8dd5>] security_sock_rcv_skb+0x75/0xb0 security/security.c:1317 [<ffffffff82c2a9e7>] sk_filter_trim_cap+0x67/0x10e0 net/core/filter.c:81 [<ffffffff82b81e60>] __sk_receive_skb+0x30/0xa00 net/core/sock.c:460 [<ffffffff838bbf12>] dccp_v4_rcv+0xdb2/0x1910 net/dccp/ipv4.c:873 [<ffffffff83069d22>] ip_local_deliver_finish+0x332/0xad0 net/ipv4/ip_input.c:216 [< inline >] NF_HOOK_THRESH ./include/linux/netfilter.h:232 [< inline >] NF_HOOK ./include/linux/netfilter.h:255 [<ffffffff8306abd2>] ip_local_deliver+0x1c2/0x4b0 net/ipv4/ip_input.c:257 [< inline >] dst_input ./include/net/dst.h:507 [<ffffffff83068500>] ip_rcv_finish+0x750/0x1c40 net/ipv4/ip_input.c:396 [< inline >] NF_HOOK_THRESH ./include/linux/netfilter.h:232 [< inline >] NF_HOOK ./include/linux/netfilter.h:255 [<ffffffff8306b82f>] ip_rcv+0x96f/0x12f0 net/ipv4/ip_input.c:487 [<ffffffff82bd9fb7>] __netif_receive_skb_core+0x1897/0x2a50 net/core/dev.c:4213 [<ffffffff82bdb19a>] __netif_receive_skb+0x2a/0x170 net/core/dev.c:4251 [<ffffffff82bdb493>] netif_receive_skb_internal+0x1b3/0x390 net/core/dev.c:4279 [<ffffffff82bdb6b8>] netif_receive_skb+0x48/0x250 net/core/dev.c:4303 [<ffffffff8241fc75>] tun_get_user+0xbd5/0x28a0 drivers/net/tun.c:1308 [<ffffffff82421b5a>] tun_chr_write_iter+0xda/0x190 drivers/net/tun.c:1332 [< inline >] new_sync_write fs/read_write.c:499 [<ffffffff8151bd44>] __vfs_write+0x334/0x570 fs/read_write.c:512 [<ffffffff8151f85b>] vfs_write+0x17b/0x500 fs/read_write.c:560 [< inline >] SYSC_write fs/read_write.c:607 [<ffffffff81523184>] SyS_write+0xd4/0x1a0 fs/read_write.c:599 [<ffffffff83fc02c1>] entry_SYSCALL_64_fastpath+0x1f/0xc2 It turns out DCCP calls __sk_receive_skb(), and this broke when lookups no longer took a reference on listeners. Fix this issue by adding a @refcounted parameter to __sk_receive_skb(), so that sock_put() is used only when needed. Fixes: 3b24d854cb35 ("tcp/dccp: do not touch listener sk_refcnt under synflood") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Andrey Konovalov <andreyknvl@google.com> Tested-by: Andrey Konovalov <andreyknvl@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-10-31net: set SK_MEM_QUANTUM to 4096Eric Dumazet1-6/+17
Systems with large pages (64KB pages for example) do not always have huge quantity of memory. A big SK_MEM_QUANTUM value leads to fewer interactions with the global counters (like tcp_memory_allocated) but might trigger memory pressure much faster, giving suboptimal TCP performance since windows are lowered to ridiculous values. Note that sysctl_mem units being in pages and in ABI, we also need to change sk_prot_mem_limits() accordingly. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-10-30Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller1-1/+3
Mostly simple overlapping changes. For example, David Ahern's adjacency list revamp in 'net-next' conflicted with an adjacency list traversal bug fix in 'net'. Signed-off-by: David S. Miller <davem@davemloft.net>
2016-10-26doc: update docbook annotations for socket and skbStephen Hemminger1-1/+3
The skbuff and sock structure both had missing parameter annotation values. Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-10-22net/socket: factor out helpers for memory and queue manipulationPaolo Abeni1-0/+4
Basic sock operations that udp code can use with its own memory accounting schema. No functional change is introduced in the existing APIs. v4 -> v5: - avoid whitespace changes v2 -> v4: - avoid exporting __sock_enqueue_skb v1 -> v2: - avoid export sock_rmem_free Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: Paolo Abeni <pabeni@redhat.com> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-23Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller1-0/+10
2016-09-17net: avoid sk_forward_alloc overflowsEric Dumazet1-0/+10
A malicious TCP receiver, sending SACK, can force the sender to split skbs in write queue and increase its memory usage. Then, when socket is closed and its write queue purged, we might overflow sk_forward_alloc (It becomes negative) sk_mem_reclaim() does nothing in this case, and more than 2GB are leaked from TCP perspective (tcp_memory_allocated is not changed) Then warnings trigger from inet_sock_destruct() and sk_stream_kill_queues() seeing a not zero sk_forward_alloc All TCP stack can be stuck because TCP is under memory pressure. A simple fix is to preemptively reclaim from sk_mem_uncharge(). This makes sure a socket wont have more than 2 MB forward allocated, after burst and idle period. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-08-23net: remove clear_sk() methodEric Dumazet1-1/+0
We no longer use this handler, we can delete it. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-08-23udp: get rid of sk_prot_clear_portaddr_nulls()Eric Dumazet1-2/+0
Since we no longer use SLAB_DESTROY_BY_RCU for UDP, we do not need sk_prot_clear_portaddr_nulls() helper. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-08-18bpf: get rid of cgroup helper related ifdefsDaniel Borkmann1-0/+10
As recently discussed during the task_under_cgroup_hierarchy() addition, we should get rid of the ifdefs surrounding the bpf_skb_under_cgroup() helper. If related functionality is not built-in, the helper cannot be used anyway, which is also in line with what we do for all other helpers. Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-07-13dccp: limit sk_filter trim to payloadWillem de Bruijn1-1/+7
Dccp verifies packet integrity, including length, at initial rcv in dccp_invalid_packet, later pulls headers in dccp_enqueue_skb. A call to sk_filter in-between can cause __skb_pull to wrap skb->len. skb_copy_datagram_msg interprets this as a negative value, so (correctly) fails with EFAULT. The negative length is reported in ioctl SIOCINQ or possibly in a DCCP_WARN in dccp_close. Introduce an sk_receive_skb variant that caps how small a filter program can trim packets, and call this in dccp with the header length. Excessively trimmed packets are now processed normally and queued for reception as 0B payloads. Fixes: 7c657876b63c ("[DCCP]: Initial implementation") Signed-off-by: Willem de Bruijn <willemb@google.com> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-05-20net: sock: move ->sk_shutdown out of bitfields.Andrey Ryabinin1-1/+8
->sk_shutdown bits share one bitfield with some other bits in sock struct, such as ->sk_no_check_[r,t]x, ->sk_userlocks ... sock_setsockopt() may write to these bits, while holding the socket lock. In case of AF_UNIX sockets, we change ->sk_shutdown bits while holding only unix_state_lock(). So concurrent setsockopt() and shutdown() may lead to corrupting these bits. Fix this by moving ->sk_shutdown bits out of bitfield into a separate byte. This will not change the 'struct sock' size since ->sk_shutdown moved into previously unused 16-bit hole. Signed-off-by: Andrey Ryabinin <aryabinin@virtuozzo.com> Suggested-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-05-04tcp: fix lockdep splat in tcp_snd_una_update()Eric Dumazet1-1/+6
tcp_snd_una_update() and tcp_rcv_nxt_update() call u64_stats_update_begin() either from process context or BH handler. This triggers a lockdep splat on 32bit & SMP builds. We could add u64_stats_update_begin_bh() variant but this would slow down 32bit builds with useless local_disable_bh() and local_enable_bh() pairs, since we own the socket lock at this point. I add sock_owned_by_me() helper to have proper lockdep support even on 64bit builds, and new u64_stats_update_begin_raw() and u64_stats_update_end_raw methods. Fixes: c10d9310edf5 ("tcp: do not assume TCP code is non preemptible") Reported-by: Fabio Estevam <festevam@gmail.com> Diagnosed-by: Francois Romieu <romieu@fr.zoreil.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Tested-by: Fabio Estevam <fabio.estevam@nxp.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-05-03net: add __sock_wfree() helperEric Dumazet1-0/+1
Hosts sending lot of ACK packets exhibit high sock_wfree() cost because of cache line miss to test SOCK_USE_WRITE_QUEUE We could move this flag close to sk_wmem_alloc but it is better to perform the atomic_sub_and_test() on a clean cache line, as it avoid one extra bus transaction. skb_orphan_partial() can also have a fast track for packets that either are TCP acks, or already went through another skb_orphan_partial() Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-05-02tcp: make tcp_sendmsg() aware of socket backlogEric Dumazet1-0/+11
Large sendmsg()/write() hold socket lock for the duration of the call, unless sk->sk_sndbuf limit is hit. This is bad because incoming packets are parked into socket backlog for a long time. Critical decisions like fast retransmit might be delayed. Receivers have to maintain a big out of order queue with additional cpu overhead, and also possible stalls in TX once windows are full. Bidirectional flows are particularly hurt since the backlog can become quite big if the copy from user space triggers IO (page faults) Some applications learnt to use sendmsg() (or sendmmsg()) with small chunks to avoid this issue. Kernel should know better, right ? Add a generic sk_flush_backlog() helper and use it right before a new skb is allocated. Typically we put 64KB of payload per skb (unless MSG_EOR is requested) and checking socket backlog every 64KB gives good results. As a matter of fact, tests with TSO/GSO disabled give very nice results, as we manage to keep a small write queue and smaller perceived rtt. Note that sk_flush_backlog() maintains socket ownership, so is not equivalent to a {release_sock(sk); lock_sock(sk);}, to ensure implicit atomicity rules that sendmsg() was giving to (possibly buggy) applications. In this simple implementation, I chose to not call tcp_release_cb(), but we might consider this later. Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Alexei Starovoitov <ast@fb.com> Cc: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Acked-by: Soheil Hassas Yeganeh <soheil@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-04-27net: SOCKWQ_ASYNC_WAITDATA optimizationsEric Dumazet1-2/+4
SOCKWQ_ASYNC_WAITDATA is set/cleared in sk_wait_data() and equivalent functions, so that sock_wake_async() can send a SIGIO only when necessary. Since these atomic operations are really not needed unless socket expressed interest in FASYNC, we can omit them in most cases. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-04-27net: SOCKWQ_ASYNC_NOSPACE optimizationsEric Dumazet1-0/+6
SOCKWQ_ASYNC_NOSPACE is tested in sock_wake_async() so that a SIGIO signal is sent when needed. tcp_sendmsg() clears the bit. tcp_poll() sets the bit when stream is not writeable. We can avoid two atomic operations by first checking if socket is actually interested in the FASYNC business (most sockets in real applications do not use AIO, but select()/poll()/epoll()) This also removes one cache line miss to access sk->sk_wq->flags in tcp_sendmsg() Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-04-25soreuseport: Resolve merge conflict for v4/v6 ordering fixCraig Gallek1-1/+5
d894ba18d4e4 ("soreuseport: fix ordering for mixed v4/v6 sockets") was merged as a bug fix to the net tree. Two conflicting changes were committed to net-next before the above fix was merged back to net-next: ca065d0cf80f ("udp: no longer use SLAB_DESTROY_BY_RCU") 3b24d854cb35 ("tcp/dccp: do not touch listener sk_refcnt under synflood") These changes switched the datastructure used for TCP and UDP sockets from hlist_nulls to hlist. This patch applies the necessary parts of the net tree fix to net-next which were not automatic as part of the merge. Fixes: 1602f49b58ab ("Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net") Signed-off-by: Craig Gallek <kraig@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-04-25sock: relax WARN_ON() in sock_owned_by_user()Eric Dumazet1-1/+1
Valdis reported tons of stack dumps caused by WARN_ON() in sock_owned_by_user() This test needs to be relaxed if/when lockdep disables itself. Note that other lockdep_sock_is_held() callers are all from rcu_dereference_protected() sections which already are disabled if/when lockdep has been disabled. Fixes: fafc4e1ea1a4 ("sock: tigthen lockdep checks for sock_owned_by_user") Reported-by: Valdis Kletnieks <Valdis.Kletnieks@vt.edu> Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-04-23Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller1-1/+5
Conflicts were two cases of simple overlapping changes, nothing serious. In the UDP case, we need to add a hlist_add_tail_rcu() to linux/rculist.h, because we've moved UDP socket handling away from using nulls lists. Signed-off-by: David S. Miller <davem@davemloft.net>
2016-04-14soreuseport: fix ordering for mixed v4/v6 socketsCraig Gallek1-1/+5
With the SO_REUSEPORT socket option, it is possible to create sockets in the AF_INET and AF_INET6 domains which are bound to the same IPv4 address. This is only possible with SO_REUSEPORT and when not using IPV6_V6ONLY on the AF_INET6 sockets. Prior to the commits referenced below, an incoming IPv4 packet would always be routed to a socket of type AF_INET when this mixed-mode was used. After those changes, the same packet would be routed to the most recently bound socket (if this happened to be an AF_INET6 socket, it would have an IPv4 mapped IPv6 address). The change in behavior occurred because the recent SO_REUSEPORT optimizations short-circuit the socket scoring logic as soon as they find a match. They did not take into account the scoring logic that favors AF_INET sockets over AF_INET6 sockets in the event of a tie. To fix this problem, this patch changes the insertion order of AF_INET and AF_INET6 addresses in the TCP and UDP socket lists when the sockets have SO_REUSEPORT set. AF_INET sockets will be inserted at the head of the list and AF_INET6 sockets with SO_REUSEPORT set will always be inserted at the tail of the list. This will force AF_INET sockets to always be considered first. Fixes: e32ea7e74727 ("soreuseport: fast reuseport UDP socket selection") Fixes: 125e80b88687 ("soreuseport: fast reuseport TCP socket selection") Reported-by: Maciej Żenczykowski <maze@google.com> Signed-off-by: Craig Gallek <kraig@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-04-13net: force inlining of netif_tx_start/stop_queue, sock_hold, __sock_putDenys Vlasenko1-2/+2
Sometimes gcc mysteriously doesn't inline very small functions we expect to be inlined. See https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66122 Arguably, gcc should do better, but gcc people aren't willing to invest time into it, asking to use __always_inline instead. With this .config: http://busybox.net/~vda/kernel_config_OPTIMIZE_INLINING_and_Os, the following functions get deinlined many times. netif_tx_stop_queue: 207 copies, 590 calls: 55 push %rbp 48 89 e5 mov %rsp,%rbp f0 80 8f e0 01 00 00 01 lock orb $0x1,0x1e0(%rdi) 5d pop %rbp c3 retq netif_tx_start_queue: 47 copies, 111 calls 55 push %rbp 48 89 e5 mov %rsp,%rbp f0 80 a7 e0 01 00 00 fe lock andb $0xfe,0x1e0(%rdi) 5d pop %rbp c3 retq sock_hold: 39 copies, 124 calls 55 push %rbp 48 89 e5 mov %rsp,%rbp f0 ff 87 80 00 00 00 lock incl 0x80(%rdi) 5d pop %rbp c3 retq __sock_put: 6 copies, 13 calls 55 push %rbp 48 89 e5 mov %rsp,%rbp f0 ff 8f 80 00 00 00 lock decl 0x80(%rdi) 5d pop %rbp c3 retq This patch fixes this via s/inline/__always_inline/. Code size decrease after the patch is ~2.5k: text data bss dec hex filename 56719876 56364551 36196352 149280779 8e5d80b vmlinux_before 56717440 56364551 36196352 149278343 8e5ce87 vmlinux Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com> CC: David S. Miller <davem@davemloft.net> CC: linux-kernel@vger.kernel.org CC: netdev@vger.kernel.org CC: netfilter-devel@vger.kernel.org Signed-off-by: David S. Miller <davem@davemloft.net>
2016-04-13sock: tigthen lockdep checks for sock_owned_by_userHannes Frederic Sowa1-15/+29
sock_owned_by_user should not be used without socket lock held. It seems to be a common practice to check .owned before lock reclassification, so provide a little help to abstract this check away. Cc: linux-cifs@vger.kernel.org Cc: linux-bluetooth@vger.kernel.org Cc: linux-nfs@vger.kernel.org Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-04-07net: Fix build failure due to lockdep_sock_is_held().David S. Miller1-0/+2
Needs to be protected with CONFIG_LOCKDEP. Based upon a patch by Hannes Frederic Sowa. Signed-off-by: David S. Miller <davem@davemloft.net>
2016-04-07sock: make lockdep_sock_is_held static inlineHannes Frederic Sowa1-1/+1
I forgot to add inline to lockdep_sock_is_held, so it generated all kinds of build warnings if not build with lockdep support. Reported-by: kbuild test robot <fengguang.wu@intel.com> Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-04-07net: introduce lockdep_is_held and update various places to use itHannes Frederic Sowa1-2/+10
The socket is either locked if we hold the slock spin_lock for lock_sock_fast and unlock_sock_fast or we own the lock (sk_lock.owned != 0). Check for this and at the same time improve that the current thread/cpu is really holding the lock. Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-04-07sock: fix lockdep annotation in release_sockHannes Frederic Sowa1-1/+6
During release_sock we use callbacks to finish the processing of outstanding skbs on the socket. We actually are still locked, sk_locked.owned == 1, but we already told lockdep that the mutex is released. This could lead to false positives in lockdep for lockdep_sock_is_held (we don't hold the slock spinlock during processing the outstanding skbs). I took over this patch from Eric Dumazet and tested it. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-04-05udp: enable MSG_PEEK at non-zero offsetsamanthakumar1-0/+2
Enable peeking at UDP datagrams at the offset specified with socket option SOL_SOCKET/SO_PEEK_OFF. Peek at any datagram in the queue, up to the end of the given datagram. Implement the SO_PEEK_OFF semantics introduced in commit ef64a54f6e55 ("sock: Introduce the SO_PEEK_OFF sock option"). Increase the offset on peek, decrease it on regular reads. When peeking, always checksum the packet immediately, to avoid recomputation on subsequent peeks and final read. The socket lock is not held for the duration of udp_recvmsg, so peek and read operations can run concurrently. Only the last store to sk_peek_off is preserved. Signed-off-by: Sam Kumar <samanthakumar@google.com> Signed-off-by: Willem de Bruijn <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-04-05udp: remove headers from UDP packets before queueingsamanthakumar1-0/+1
Remove UDP transport headers before queueing packets for reception. This change simplifies a follow-up patch to add MSG_PEEK support. Signed-off-by: Sam Kumar <samanthakumar@google.com> Signed-off-by: Willem de Bruijn <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-04-05sock: convert sk_peek_offset functions to WRITE_ONCEWillem de Bruijn1-11/+13
Make the peek offset interface safe to use in lockless environments. Use READ_ONCE and WRITE_ONCE to avoid race conditions between testing and updating the peek offset. Suggested-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Willem de Bruijn <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-04-04tcp: increment sk_drops for dropped rx packetsEric Dumazet1-0/+7
Now ss can report sk_drops, we can instruct TCP to increment this per socket counter when it drops an incoming frame, to refine monitoring and debugging. Following patch takes care of listeners drops. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-04-04udp: no longer use SLAB_DESTROY_BY_RCUEric Dumazet1-6/+6
Tom Herbert would like not touching UDP socket refcnt for encapsulated traffic. For this to happen, we need to use normal RCU rules, with a grace period before freeing a socket. UDP sockets are not short lived in the high usage case, so the added cost of call_rcu() should not be a concern. This actually removes a lot of complexity in UDP stack. Multicast receives no longer need to hold a bucket spinlock. Note that ip early demux still needs to take a reference on the socket. Same remark for functions used by xt_socket and xt_PROXY netfilter modules, but this might be changed later. Performance for a single UDP socket receiving flood traffic from many RX queues/cpus. Simple udp_rx using simple recvfrom() loop : 438 kpps instead of 374 kpps : 17 % increase of the peak rate. v2: Addressed Willem de Bruijn feedback in multicast handling - keep early demux break in __udp4_lib_demux_lookup() Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Tom Herbert <tom@herbertland.com> Cc: Willem de Bruijn <willemb@google.com> Tested-by: Tom Herbert <tom@herbertland.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-04-04net: add SOCK_RCU_FREE socket flagEric Dumazet1-0/+2
We want a generic way to insert an RCU grace period before socket freeing for cases where RCU_SLAB_DESTROY_BY_RCU is adding too much overhead. SLAB_DESTROY_BY_RCU strict rules force us to take a reference on the socket sk_refcnt, and it is a performance problem for UDP encapsulation, or TCP synflood behavior, as many CPUs might attempt the atomic operations on a shared sk_refcnt UDP sockets and TCP listeners can set SOCK_RCU_FREE so that their lookup can use traditional RCU rules, without refcount changes. They can set the flag only once hashed and visible by other cpus. Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Tom Herbert <tom@herbertland.com> Tested-by: Tom Herbert <tom@herbertland.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-04-04sock: enable timestamping using control messagesSoheil Hassas Yeganeh1-4/+6
Currently, SOL_TIMESTAMPING can only be enabled using setsockopt. This is very costly when users want to sample writes to gather tx timestamps. Add support for enabling SO_TIMESTAMPING via control messages by using tsflags added in `struct sockcm_cookie` (added in the previous patches in this series) to set the tx_flags of the last skb created in a sendmsg. With this patch, the timestamp recording bits in tx_flags of the skbuff is overridden if SO_TIMESTAMPING is passed in a cmsg. Please note that this is only effective for overriding the recording timestamps flags. Users should enable timestamp reporting (e.g., SOF_TIMESTAMPING_SOFTWARE | SOF_TIMESTAMPING_OPT_ID) using socket options and then should ask for SOF_TIMESTAMPING_TX_* using control messages per sendmsg to sample timestamps for each write. Signed-off-by: Soheil Hassas Yeganeh <soheil@google.com> Acked-by: Willem de Bruijn <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-04-04sock: accept SO_TIMESTAMPING flags in socket cmsgSoheil Hassas Yeganeh1-0/+1
Accept SO_TIMESTAMPING in control messages of the SOL_SOCKET level as a basis to accept timestamping requests per write. This implementation only accepts TX recording flags (i.e., SOF_TIMESTAMPING_TX_HARDWARE, SOF_TIMESTAMPING_TX_SOFTWARE, SOF_TIMESTAMPING_TX_SCHED, and SOF_TIMESTAMPING_TX_ACK) in control messages. Users need to set reporting flags (e.g., SOF_TIMESTAMPING_OPT_ID) per socket via socket options. This commit adds a tsflags field in sockcm_cookie which is set in __sock_cmsg_send. It only override the SOF_TIMESTAMPING_TX_* bits in sockcm_cookie.tsflags allowing the control message to override the recording behavior per write, yet maintaining the value of other flags. This patch implements validating the control message and setting tsflags in struct sockcm_cookie. Next commits in this series will actually implement timestamping per write for different protocols. Signed-off-by: Soheil Hassas Yeganeh <soheil@google.com> Acked-by: Willem de Bruijn <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>