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2020-12-04net-zerocopy: Refactor skb frag fast-forward op.Arjun Roy
Refactor skb frag fast-forwarding for tcp receive zerocopy. This is part of a patch set that introduces short-circuited hybrid copies for small receive operations, which results in roughly 33% fewer syscalls for small RPC scenarios. skb_advance_to_frag(), given a skb and an offset into the skb, iterates from the first frag for the skb until we're at the frag specified by the offset. Assuming the offset provided refers to how many bytes in the skb are already read, the returned frag points to the next frag we may read from, while offset_frag is set to the number of bytes from this frag that we have already read. If frag is not null and offset_frag is equal to 0, then we may be able to map this frag's page into the process address space with vm_insert_page(). However, if offset_frag is not equal to 0, then we cannot do so. Signed-off-by: Arjun Roy <arjunroy@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Soheil Hassas Yeganeh <soheil@google.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-12-04net-tcp: Introduce tcp_recvmsg_locked().Arjun Roy
Refactor tcp_recvmsg() by splitting it into locked and unlocked portions. Callers already holding the socket lock and not using ERRQUEUE/cmsg/busy polling can simply call tcp_recvmsg_locked(). This is in preparation for a short-circuit copy performed by TCP receive zerocopy for small (< PAGE_SIZE, or otherwise requested by the user) reads. Signed-off-by: Arjun Roy <arjunroy@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Soheil Hassas Yeganeh <soheil@google.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-12-04net-zerocopy: Copy straggler unaligned data for TCP Rx. zerocopy.Arjun Roy
When TCP receive zerocopy does not successfully map the entire requested space, it outputs a 'hint' that the caller should recvmsg(). Augment zerocopy to accept a user buffer that it tries to copy this hint into - if it is possible to copy the entire hint, it will do so. This elides a recvmsg() call for received traffic that isn't exactly page-aligned in size. This was tested with RPC-style traffic of arbitrary sizes. Normally, each received message required at least one getsockopt() call, and one recvmsg() call for the remaining unaligned data. With this change, almost all of the recvmsg() calls are eliminated, leading to a savings of about 25%-50% in number of system calls for RPC-style workloads. Signed-off-by: Arjun Roy <arjunroy@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Soheil Hassas Yeganeh <soheil@google.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-12-04Merge https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-nextJakub Kicinski
Alexei Starovoitov says: ==================== pull-request: bpf-next 2020-12-03 The main changes are: 1) Support BTF in kernel modules, from Andrii. 2) Introduce preferred busy-polling, from Björn. 3) bpf_ima_inode_hash() and bpf_bprm_opts_set() helpers, from KP Singh. 4) Memcg-based memory accounting for bpf objects, from Roman. 5) Allow bpf_{s,g}etsockopt from cgroup bind{4,6} hooks, from Stanislav. * https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (118 commits) selftests/bpf: Fix invalid use of strncat in test_sockmap libbpf: Use memcpy instead of strncpy to please GCC selftests/bpf: Add fentry/fexit/fmod_ret selftest for kernel module selftests/bpf: Add tp_btf CO-RE reloc test for modules libbpf: Support attachment of BPF tracing programs to kernel modules libbpf: Factor out low-level BPF program loading helper bpf: Allow to specify kernel module BTFs when attaching BPF programs bpf: Remove hard-coded btf_vmlinux assumption from BPF verifier selftests/bpf: Add CO-RE relocs selftest relying on kernel module BTF selftests/bpf: Add support for marking sub-tests as skipped selftests/bpf: Add bpf_testmod kernel module for testing libbpf: Add kernel module BTF support for CO-RE relocations libbpf: Refactor CO-RE relocs to not assume a single BTF object libbpf: Add internal helper to load BTF data by FD bpf: Keep module's btf_data_size intact after load bpf: Fix bpf_put_raw_tracepoint()'s use of __module_address() selftests/bpf: Add Userspace tests for TCP_WINDOW_CLAMP bpf: Adds support for setting window clamp samples/bpf: Fix spelling mistake "recieving" -> "receiving" bpf: Fix cold build of test_progs-no_alu32 ... ==================== Link: https://lore.kernel.org/r/20201204021936.85653-1-alexei.starovoitov@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-12-03bpf: Adds support for setting window clampPrankur gupta
Adds a new bpf_setsockopt for TCP sockets, TCP_BPF_WINDOW_CLAMP, which sets the maximum receiver window size. It will be useful for limiting receiver window based on RTT. Signed-off-by: Prankur gupta <prankgup@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20201202213152.435886-2-prankgup@fb.com
2020-11-16tcp: factor out __tcp_close() helperPaolo Abeni
unlocked version of protocol level close, will be used by MPTCP to allow decouple orphaning and subflow level close. Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-11-16tcp: factor out tcp_build_frag()Paolo Abeni
Will be needed by the next patch, as MPTCP needs to handle directly the error/memory-allocation-needed path. No functional changes intended. Additionally let MPTCP code access the tcp_remove_empty_skb() helper. Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-10-23tcp: Prevent low rmem stalls with SO_RCVLOWAT.Arjun Roy
With SO_RCVLOWAT, under memory pressure, it is possible to enter a state where: 1. We have not received enough bytes to satisfy SO_RCVLOWAT. 2. We have not entered buffer pressure (see tcp_rmem_pressure()). 3. But, we do not have enough buffer space to accept more packets. In this case, we advertise 0 rwnd (due to #3) but the application does not drain the receive queue (no wakeup because of #1 and #2) so the flow stalls. Modify the heuristic for SO_RCVLOWAT so that, if we are advertising rwnd<=rcv_mss, force a wakeup to prevent a stall. Without this patch, setting tcp_rmem to 6143 and disabling TCP autotune causes a stalled flow. With this patch, no stall occurs. This is with RPC-style traffic with large messages. Fixes: 03f45c883c6f ("tcp: avoid extra wakeups for SO_RCVLOWAT users") Signed-off-by: Arjun Roy <arjunroy@google.com> Acked-by: Soheil Hassas Yeganeh <soheil@google.com> Acked-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Link: https://lore.kernel.org/r/20201023184709.217614-1-arjunroy.kdev@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-10-05Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netDavid S. Miller
Rejecting non-native endian BTF overlapped with the addition of support for it. The rest were more simple overlapping changes, except the renesas ravb binding update, which had to follow a file move as well as a YAML conversion. Signed-off-by: David S. Miller <davem@davemloft.net>
2020-10-02tcp: use sendpage_ok() to detect misused .sendpageColy Li
commit a10674bf2406 ("tcp: detecting the misuse of .sendpage for Slab objects") adds the checks for Slab pages, but the pages don't have page_count are still missing from the check. Network layer's sendpage method is not designed to send page_count 0 pages neither, therefore both PageSlab() and page_count() should be both checked for the sending page. This is exactly what sendpage_ok() does. This patch uses sendpage_ok() in do_tcp_sendpages() to detect misused .sendpage, to make the code more robust. Fixes: a10674bf2406 ("tcp: detecting the misuse of .sendpage for Slab objects") Suggested-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: Coly Li <colyli@suse.de> Cc: Vasily Averin <vvs@virtuozzo.com> Cc: David S. Miller <davem@davemloft.net> Cc: stable@vger.kernel.org Signed-off-by: David S. Miller <davem@davemloft.net>
2020-09-30inet: remove icsk_ack.blockedEric Dumazet
TCP has been using it to work around the possibility of tcp_delack_timer() finding the socket owned by user. After commit 6f458dfb4092 ("tcp: improve latencies of timer triggered events") we added TCP_DELACK_TIMER_DEFERRED atomic bit for more immediate recovery, so we can get rid of icsk_ack.blocked This frees space that following patch will reuse. Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Soheil Hassas Yeganeh <soheil@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-09-23Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-nextDavid S. Miller
Alexei Starovoitov says: ==================== pull-request: bpf-next 2020-09-23 The following pull-request contains BPF updates for your *net-next* tree. We've added 95 non-merge commits during the last 22 day(s) which contain a total of 124 files changed, 4211 insertions(+), 2040 deletions(-). The main changes are: 1) Full multi function support in libbpf, from Andrii. 2) Refactoring of function argument checks, from Lorenz. 3) Make bpf_tail_call compatible with functions (subprograms), from Maciej. 4) Program metadata support, from YiFei. 5) bpf iterator optimizations, from Yonghong. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
2020-09-14tcp: schedule EPOLLOUT after a partial sendmsgSoheil Hassas Yeganeh
For EPOLLET, applications must call sendmsg until they get EAGAIN. Otherwise, there is no guarantee that EPOLLOUT is sent if there was a failure upon memory allocation. As a result on high-speed NICs, userspace observes multiple small sendmsgs after a partial sendmsg until EAGAIN, since TCP can send 1-2 TSOs in between two sendmsg syscalls: // One large partial send due to memory allocation failure. sendmsg(20MB) = 2MB // Many small sends until EAGAIN. sendmsg(18MB) = 64KB sendmsg(17.9MB) = 128KB sendmsg(17.8MB) = 64KB ... sendmsg(...) = EAGAIN // At this point, userspace can assume an EPOLLOUT. To fix this, set the SOCK_NOSPACE on all partial sendmsg scenarios to guarantee that we send EPOLLOUT after partial sendmsg. After this commit userspace can assume that it will receive an EPOLLOUT after the first partial sendmsg. This EPOLLOUT will benefit from sk_stream_write_space() logic delaying the EPOLLOUT until significant space is available in write queue. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Soheil Hassas Yeganeh <soheil@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-09-14tcp: return EPOLLOUT from tcp_poll only when notsent_bytes is half the limitSoheil Hassas Yeganeh
If there was any event available on the TCP socket, tcp_poll() will be called to retrieve all the events. In tcp_poll(), we call sk_stream_is_writeable() which returns true as long as we are at least one byte below notsent_lowat. This will result in quite a few spurious EPLLOUT and frequent tiny sendmsg() calls as a result. Similar to sk_stream_write_space(), use __sk_stream_is_writeable with a wake value of 1, so that we set EPOLLOUT only if half the space is available for write. Signed-off-by: Soheil Hassas Yeganeh <soheil@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-09-14mptcp: call tcp_cleanup_rbuf on subflowsPaolo Abeni
That is needed to let the subflows announce promptly when new space is available in the receive buffer. tcp_cleanup_rbuf() is currently a static function, drop the scope modifier and add a declaration in the TCP header. Reviewed-by: Mat Martineau <mathew.j.martineau@linux.intel.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-09-10tcp: simplify tcp_set_congestion_control(): Always reinitializeNeal Cardwell
Now that the previous patches ensure that all call sites for tcp_set_congestion_control() want to initialize congestion control, we can simplify tcp_set_congestion_control() by removing the reinit argument and the code to support it. Signed-off-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Yuchung Cheng <ycheng@google.com> Acked-by: Kevin Yang <yyd@google.com> Cc: Lawrence Brakmo <brakmo@fb.com>
2020-09-10tcp: Only init congestion control if not initialized alreadyNeal Cardwell
Change tcp_init_transfer() to only initialize congestion control if it has not been initialized already. With this new approach, we can arrange things so that if the EBPF code sets the congestion control by calling setsockopt(TCP_CONGESTION) then tcp_init_transfer() will not re-initialize the CC module. This is an approach that has the following beneficial properties: (1) This allows CC module customizations made by the EBPF called in tcp_init_transfer() to persist, and not be wiped out by a later call to tcp_init_congestion_control() in tcp_init_transfer(). (2) Does not flip the order of EBPF and CC init, to avoid causing bugs for existing code upstream that depends on the current order. (3) Does not cause 2 initializations for for CC in the case where the EBPF called in tcp_init_transfer() wants to set the CC to a new CC algorithm. (4) Allows follow-on simplifications to the code in net/core/filter.c and net/ipv4/tcp_cong.c, which currently both have some complexity to special-case CC initialization to avoid double CC initialization if EBPF sets the CC. Signed-off-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Yuchung Cheng <ycheng@google.com> Acked-by: Kevin Yang <yyd@google.com> Cc: Lawrence Brakmo <brakmo@fb.com>
2020-08-24tcp: bpf: Optionally store mac header in TCP_SAVE_SYNMartin KaFai Lau
This patch is adapted from Eric's patch in an earlier discussion [1]. The TCP_SAVE_SYN currently only stores the network header and tcp header. This patch allows it to optionally store the mac header also if the setsockopt's optval is 2. It requires one more bit for the "save_syn" bit field in tcp_sock. This patch achieves this by moving the syn_smc bit next to the is_mptcp. The syn_smc is currently used with the TCP experimental option. Since syn_smc is only used when CONFIG_SMC is enabled, this patch also puts the "IS_ENABLED(CONFIG_SMC)" around it like the is_mptcp did with "IS_ENABLED(CONFIG_MPTCP)". The mac_hdrlen is also stored in the "struct saved_syn" to allow a quick offset from the bpf prog if it chooses to start getting from the network header or the tcp header. [1]: https://lore.kernel.org/netdev/CANn89iLJNWh6bkH7DNhy_kmcAexuUCccqERqe7z2QsvPhGrYPQ@mail.gmail.com/ Suggested-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Martin KaFai Lau <kafai@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Reviewed-by: Eric Dumazet <edumazet@google.com> Link: https://lore.kernel.org/bpf/20200820190123.2886935-1-kafai@fb.com
2020-08-24tcp: bpf: Add TCP_BPF_RTO_MIN for bpf_setsockoptMartin KaFai Lau
This patch adds bpf_setsockopt(TCP_BPF_RTO_MIN) to allow bpf prog to set the min rto of a connection. It could be used together with the earlier patch which has added bpf_setsockopt(TCP_BPF_DELACK_MAX). A later selftest patch will communicate the max delay ack in a bpf tcp header option and then the receiving side can use bpf_setsockopt(TCP_BPF_RTO_MIN) to set a shorter rto. Signed-off-by: Martin KaFai Lau <kafai@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Reviewed-by: Eric Dumazet <edumazet@google.com> Acked-by: John Fastabend <john.fastabend@gmail.com> Link: https://lore.kernel.org/bpf/20200820190027.2884170-1-kafai@fb.com
2020-08-24tcp: bpf: Add TCP_BPF_DELACK_MAX setsockoptMartin KaFai Lau
This change is mostly from an internal patch and adapts it from sysctl config to the bpf_setsockopt setup. The bpf_prog can set the max delay ack by using bpf_setsockopt(TCP_BPF_DELACK_MAX). This max delay ack can be communicated to its peer through bpf header option. The receiving peer can then use this max delay ack and set a potentially lower rto by using bpf_setsockopt(TCP_BPF_RTO_MIN) which will be introduced in the next patch. Another later selftest patch will also use it like the above to show how to write and parse bpf tcp header option. Signed-off-by: Martin KaFai Lau <kafai@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Reviewed-by: Eric Dumazet <edumazet@google.com> Acked-by: John Fastabend <john.fastabend@gmail.com> Link: https://lore.kernel.org/bpf/20200820190021.2884000-1-kafai@fb.com
2020-08-24tcp: Use a struct to represent a saved_synMartin KaFai Lau
The TCP_SAVE_SYN has both the network header and tcp header. The total length of the saved syn packet is currently stored in the first 4 bytes (u32) of an array and the actual packet data is stored after that. A later patch will add a bpf helper that allows to get the tcp header alone from the saved syn without the network header. It will be more convenient to have a direct offset to a specific header instead of re-parsing it. This requires to separately store the network hdrlen. The total header length (i.e. network + tcp) is still needed for the current usage in getsockopt. Although this total length can be obtained by looking into the tcphdr and then get the (th->doff << 2), this patch chooses to directly store the tcp hdrlen in the second four bytes of this newly created "struct saved_syn". By using a new struct, it can give a readable name to each individual header length. Signed-off-by: Martin KaFai Lau <kafai@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Reviewed-by: Eric Dumazet <edumazet@google.com> Acked-by: John Fastabend <john.fastabend@gmail.com> Link: https://lore.kernel.org/bpf/20200820190014.2883694-1-kafai@fb.com
2020-08-10tcp: correct read of TFO keys on big endian systemsJason Baron
When TFO keys are read back on big endian systems either via the global sysctl interface or via getsockopt() using TCP_FASTOPEN_KEY, the values don't match what was written. For example, on s390x: # echo "1-2-3-4" > /proc/sys/net/ipv4/tcp_fastopen_key # cat /proc/sys/net/ipv4/tcp_fastopen_key 02000000-01000000-04000000-03000000 Instead of: # cat /proc/sys/net/ipv4/tcp_fastopen_key 00000001-00000002-00000003-00000004 Fix this by converting to the correct endianness on read. This was reported by Colin Ian King when running the 'tcp_fastopen_backup_key' net selftest on s390x, which depends on the read value matching what was written. I've confirmed that the test now passes on big and little endian systems. Signed-off-by: Jason Baron <jbaron@akamai.com> Fixes: 438ac88009bc ("net: fastopen: robustness and endianness fixes for SipHash") Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Eric Dumazet <edumazet@google.com> Reported-and-tested-by: Colin Ian King <colin.king@canonical.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-07-31tcp: add earliest departure time to SCM_TIMESTAMPING_OPT_STATSYousuk Seung
This change adds TCP_NLA_EDT to SCM_TIMESTAMPING_OPT_STATS that reports the earliest departure time(EDT) of the timestamped skb. By tracking EDT values of the skb from different timestamps, we can observe when and how much the value changed. This allows to measure the precise delay injected on the sender host e.g. by a bpf-base throttler. Signed-off-by: Yousuk Seung <ysseung@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Neal Cardwell <ncardwell@google.com> Acked-by: Soheil Hassas Yeganeh <soheil@google.com> Acked-by: Yuchung Cheng <ycheng@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-07-28net: remove sockptr_advanceChristoph Hellwig
sockptr_advance never properly worked. Replace it with _offset variants of copy_from_sockptr and copy_to_sockptr. Fixes: ba423fdaa589 ("net: add a new sockptr_t type") Reported-by: Jason A. Donenfeld <Jason@zx2c4.com> Reported-by: Ido Schimmel <idosch@idosch.org> Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Jason A. Donenfeld <Jason@zx2c4.com> Tested-by: Ido Schimmel <idosch@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-07-24net: pass a sockptr_t into ->setsockoptChristoph Hellwig
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>
2020-07-24net/tcp: switch do_tcp_setsockopt to sockptr_tChristoph Hellwig
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>
2020-07-24net/tcp: switch ->md5_parse to sockptr_tChristoph Hellwig
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>
2020-07-19net/ipv6: remove compat_ipv6_{get,set}sockoptChristoph Hellwig
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>
2020-07-11Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netDavid S. Miller
All conflicts seemed rather trivial, with some guidance from Saeed Mameed on the tc_ct.c one. Signed-off-by: David S. Miller <davem@davemloft.net>
2020-07-09tcp: make sure listeners don't initialize congestion-control stateChristoph Paasch
syzkaller found its way into setsockopt with TCP_CONGESTION "cdg". tcp_cdg_init() does a kcalloc to store the gradients. As sk_clone_lock just copies all the memory, the allocated pointer will be copied as well, if the app called setsockopt(..., TCP_CONGESTION) on the listener. If now the socket will be destroyed before the congestion-control has properly been initialized (through a call to tcp_init_transfer), we will end up freeing memory that does not belong to that particular socket, opening the door to a double-free: [ 11.413102] ================================================================== [ 11.414181] BUG: KASAN: double-free or invalid-free in tcp_cleanup_congestion_control+0x58/0xd0 [ 11.415329] [ 11.415560] CPU: 3 PID: 4884 Comm: syz-executor.5 Not tainted 5.8.0-rc2 #80 [ 11.416544] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.12.1-0-ga5cab58e9a3f-prebuilt.qemu.org 04/01/2014 [ 11.418148] Call Trace: [ 11.418534] <IRQ> [ 11.418834] dump_stack+0x7d/0xb0 [ 11.419297] print_address_description.constprop.0+0x1a/0x210 [ 11.422079] kasan_report_invalid_free+0x51/0x80 [ 11.423433] __kasan_slab_free+0x15e/0x170 [ 11.424761] kfree+0x8c/0x230 [ 11.425157] tcp_cleanup_congestion_control+0x58/0xd0 [ 11.425872] tcp_v4_destroy_sock+0x57/0x5a0 [ 11.426493] inet_csk_destroy_sock+0x153/0x2c0 [ 11.427093] tcp_v4_syn_recv_sock+0xb29/0x1100 [ 11.427731] tcp_get_cookie_sock+0xc3/0x4a0 [ 11.429457] cookie_v4_check+0x13d0/0x2500 [ 11.433189] tcp_v4_do_rcv+0x60e/0x780 [ 11.433727] tcp_v4_rcv+0x2869/0x2e10 [ 11.437143] ip_protocol_deliver_rcu+0x23/0x190 [ 11.437810] ip_local_deliver+0x294/0x350 [ 11.439566] __netif_receive_skb_one_core+0x15d/0x1a0 [ 11.441995] process_backlog+0x1b1/0x6b0 [ 11.443148] net_rx_action+0x37e/0xc40 [ 11.445361] __do_softirq+0x18c/0x61a [ 11.445881] asm_call_on_stack+0x12/0x20 [ 11.446409] </IRQ> [ 11.446716] do_softirq_own_stack+0x34/0x40 [ 11.447259] do_softirq.part.0+0x26/0x30 [ 11.447827] __local_bh_enable_ip+0x46/0x50 [ 11.448406] ip_finish_output2+0x60f/0x1bc0 [ 11.450109] __ip_queue_xmit+0x71c/0x1b60 [ 11.451861] __tcp_transmit_skb+0x1727/0x3bb0 [ 11.453789] tcp_rcv_state_process+0x3070/0x4d3a [ 11.456810] tcp_v4_do_rcv+0x2ad/0x780 [ 11.457995] __release_sock+0x14b/0x2c0 [ 11.458529] release_sock+0x4a/0x170 [ 11.459005] __inet_stream_connect+0x467/0xc80 [ 11.461435] inet_stream_connect+0x4e/0xa0 [ 11.462043] __sys_connect+0x204/0x270 [ 11.465515] __x64_sys_connect+0x6a/0xb0 [ 11.466088] do_syscall_64+0x3e/0x70 [ 11.466617] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 11.467341] RIP: 0033:0x7f56046dc469 [ 11.467844] Code: Bad RIP value. [ 11.468282] RSP: 002b:00007f5604dccdd8 EFLAGS: 00000246 ORIG_RAX: 000000000000002a [ 11.469326] RAX: ffffffffffffffda RBX: 000000000068bf00 RCX: 00007f56046dc469 [ 11.470379] RDX: 0000000000000010 RSI: 0000000020000000 RDI: 0000000000000004 [ 11.471311] RBP: 00000000ffffffff R08: 0000000000000000 R09: 0000000000000000 [ 11.472286] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 [ 11.473341] R13: 000000000041427c R14: 00007f5604dcd5c0 R15: 0000000000000003 [ 11.474321] [ 11.474527] Allocated by task 4884: [ 11.475031] save_stack+0x1b/0x40 [ 11.475548] __kasan_kmalloc.constprop.0+0xc2/0xd0 [ 11.476182] tcp_cdg_init+0xf0/0x150 [ 11.476744] tcp_init_congestion_control+0x9b/0x3a0 [ 11.477435] tcp_set_congestion_control+0x270/0x32f [ 11.478088] do_tcp_setsockopt.isra.0+0x521/0x1a00 [ 11.478744] __sys_setsockopt+0xff/0x1e0 [ 11.479259] __x64_sys_setsockopt+0xb5/0x150 [ 11.479895] do_syscall_64+0x3e/0x70 [ 11.480395] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 11.481097] [ 11.481321] Freed by task 4872: [ 11.481783] save_stack+0x1b/0x40 [ 11.482230] __kasan_slab_free+0x12c/0x170 [ 11.482839] kfree+0x8c/0x230 [ 11.483240] tcp_cleanup_congestion_control+0x58/0xd0 [ 11.483948] tcp_v4_destroy_sock+0x57/0x5a0 [ 11.484502] inet_csk_destroy_sock+0x153/0x2c0 [ 11.485144] tcp_close+0x932/0xfe0 [ 11.485642] inet_release+0xc1/0x1c0 [ 11.486131] __sock_release+0xc0/0x270 [ 11.486697] sock_close+0xc/0x10 [ 11.487145] __fput+0x277/0x780 [ 11.487632] task_work_run+0xeb/0x180 [ 11.488118] __prepare_exit_to_usermode+0x15a/0x160 [ 11.488834] do_syscall_64+0x4a/0x70 [ 11.489326] entry_SYSCALL_64_after_hwframe+0x44/0xa9 Wei Wang fixed a part of these CDG-malloc issues with commit c12014440750 ("tcp: memset ca_priv data to 0 properly"). This patch here fixes the listener-scenario: We make sure that listeners setting the congestion-control through setsockopt won't initialize it (thus CDG never allocates on listeners). For those who use AF_UNSPEC to reuse a socket, tcp_disconnect() is changed to cleanup afterwards. (The issue can be reproduced at least down to v4.4.x.) Cc: Wei Wang <weiwan@google.com> Cc: Eric Dumazet <edumazet@google.com> Fixes: 2b0a8c9eee81 ("tcp: add CDG congestion control") Signed-off-by: Christoph Paasch <cpaasch@apple.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-07-02tcp: md5: allow changing MD5 keys in all socket statesEric Dumazet
This essentially reverts commit 721230326891 ("tcp: md5: reject TCP_MD5SIG or TCP_MD5SIG_EXT on established sockets") Mathieu reported that many vendors BGP implementations can actually switch TCP MD5 on established flows. Quoting Mathieu : Here is a list of a few network vendors along with their behavior with respect to TCP MD5: - Cisco: Allows for password to be changed, but within the hold-down timer (~180 seconds). - Juniper: When password is initially set on active connection it will reset, but after that any subsequent password changes no network resets. - Nokia: No notes on if they flap the tcp connection or not. - Ericsson/RedBack: Allows for 2 password (old/new) to co-exist until both sides are ok with new passwords. - Meta-Switch: Expects the password to be set before a connection is attempted, but no further info on whether they reset the TCP connection on a change. - Avaya: Disable the neighbor, then set password, then re-enable. - Zebos: Would normally allow the change when socket connected. We can revert my prior change because commit 9424e2e7ad93 ("tcp: md5: fix potential overestimation of TCP option space") removed the leak of 4 kernel bytes to the wire that was the main reason for my patch. While doing my investigations, I found a bug when a MD5 key is changed, leading to these commits that stable teams want to consider before backporting this revert : Commit 6a2febec338d ("tcp: md5: add missing memory barriers in tcp_md5_do_add()/tcp_md5_hash_key()") Commit e6ced831ef11 ("tcp: md5: refine tcp_md5_do_add()/tcp_md5_hash_key() barriers") Fixes: 721230326891 "tcp: md5: reject TCP_MD5SIG or TCP_MD5SIG_EXT on established sockets" Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-07-01tcp: md5: refine tcp_md5_do_add()/tcp_md5_hash_key() barriersEric Dumazet
My prior fix went a bit too far, according to Herbert and Mathieu. Since we accept that concurrent TCP MD5 lookups might see inconsistent keys, we can use READ_ONCE()/WRITE_ONCE() instead of smp_rmb()/smp_wmb() Clearing all key->key[] is needed to avoid possible KMSAN reports, if key->keylen is increased. Since tcp_md5_do_add() is not fast path, using __GFP_ZERO to clear all struct tcp_md5sig_key is simpler. data_race() was added in linux-5.8 and will prevent KCSAN reports, this can safely be removed in stable backports, if data_race() is not yet backported. v2: use data_race() both in tcp_md5_hash_key() and tcp_md5_do_add() Fixes: 6a2febec338d ("tcp: md5: add missing memory barriers in tcp_md5_do_add()/tcp_md5_hash_key()") Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Herbert Xu <herbert@gondor.apana.org.au> Cc: Marco Elver <elver@google.com> Reviewed-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Acked-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-06-30tcp: md5: add missing memory barriers in tcp_md5_do_add()/tcp_md5_hash_key()Eric Dumazet
MD5 keys are read with RCU protection, and tcp_md5_do_add() might update in-place a prior key. Normally, typical RCU updates would allocate a new piece of memory. In this case only key->key and key->keylen might be updated, and we do not care if an incoming packet could see the old key, the new one, or some intermediate value, since changing the key on a live flow is known to be problematic anyway. We only want to make sure that in the case key->keylen is changed, cpus in tcp_md5_hash_key() wont try to use uninitialized data, or crash because key->keylen was read twice to feed sg_init_one() and ahash_request_set_crypt() Fixes: 9ea88a153001 ("tcp: md5: check md5 signature without socket lock") Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-06-24tcp: Expose tcp_sock_set_keepidle_lockedDmitry Yakunin
This is preparation for usage in bpf_setsockopt. v2: - remove redundant EXPORT_SYMBOL (Alexei Starovoitov) Signed-off-by: Dmitry Yakunin <zeil@yandex-team.ru> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20200620153052.9439-2-zeil@yandex-team.ru
2020-06-13Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netLinus Torvalds
Pull networking fixes from David Miller: 1) Fix cfg80211 deadlock, from Johannes Berg. 2) RXRPC fails to send norigications, from David Howells. 3) MPTCP RM_ADDR parsing has an off by one pointer error, fix from Geliang Tang. 4) Fix crash when using MSG_PEEK with sockmap, from Anny Hu. 5) The ucc_geth driver needs __netdev_watchdog_up exported, from Valentin Longchamp. 6) Fix hashtable memory leak in dccp, from Wang Hai. 7) Fix how nexthops are marked as FDB nexthops, from David Ahern. 8) Fix mptcp races between shutdown and recvmsg, from Paolo Abeni. 9) Fix crashes in tipc_disc_rcv(), from Tuong Lien. 10) Fix link speed reporting in iavf driver, from Brett Creeley. 11) When a channel is used for XSK and then reused again later for XSK, we forget to clear out the relevant data structures in mlx5 which causes all kinds of problems. Fix from Maxim Mikityanskiy. 12) Fix memory leak in genetlink, from Cong Wang. 13) Disallow sockmap attachments to UDP sockets, it simply won't work. From Lorenz Bauer. * git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (83 commits) net: ethernet: ti: ale: fix allmulti for nu type ale net: ethernet: ti: am65-cpsw-nuss: fix ale parameters init net: atm: Remove the error message according to the atomic context bpf: Undo internal BPF_PROBE_MEM in BPF insns dump libbpf: Support pre-initializing .bss global variables tools/bpftool: Fix skeleton codegen bpf: Fix memlock accounting for sock_hash bpf: sockmap: Don't attach programs to UDP sockets bpf: tcp: Recv() should return 0 when the peer socket is closed ibmvnic: Flush existing work items before device removal genetlink: clean up family attributes allocations net: ipa: header pad field only valid for AP->modem endpoint net: ipa: program upper nibbles of sequencer type net: ipa: fix modem LAN RX endpoint id net: ipa: program metadata mask differently ionic: add pcie_print_link_status rxrpc: Fix race between incoming ACK parser and retransmitter net/mlx5: E-Switch, Fix some error pointer dereferences net/mlx5: Don't fail driver on failure to create debugfs net/mlx5e: CT: Fix ipv6 nat header rewrite actions ...
2020-06-09mmap locking API: convert mmap_sem API commentsMichel Lespinasse
Convert comments that reference old mmap_sem APIs to reference corresponding new mmap locking APIs instead. Signed-off-by: Michel Lespinasse <walken@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Vlastimil Babka <vbabka@suse.cz> Reviewed-by: Davidlohr Bueso <dbueso@suse.de> Reviewed-by: Daniel Jordan <daniel.m.jordan@oracle.com> Cc: David Rientjes <rientjes@google.com> Cc: Hugh Dickins <hughd@google.com> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: Jerome Glisse <jglisse@redhat.com> Cc: John Hubbard <jhubbard@nvidia.com> Cc: Laurent Dufour <ldufour@linux.ibm.com> Cc: Liam Howlett <Liam.Howlett@oracle.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ying Han <yinghan@google.com> Link: http://lkml.kernel.org/r/20200520052908.204642-12-walken@google.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-09mmap locking API: use coccinelle to convert mmap_sem rwsem call sitesMichel Lespinasse
This change converts the existing mmap_sem rwsem calls to use the new mmap locking API instead. The change is generated using coccinelle with the following rule: // spatch --sp-file mmap_lock_api.cocci --in-place --include-headers --dir . @@ expression mm; @@ ( -init_rwsem +mmap_init_lock | -down_write +mmap_write_lock | -down_write_killable +mmap_write_lock_killable | -down_write_trylock +mmap_write_trylock | -up_write +mmap_write_unlock | -downgrade_write +mmap_write_downgrade | -down_read +mmap_read_lock | -down_read_killable +mmap_read_lock_killable | -down_read_trylock +mmap_read_trylock | -up_read +mmap_read_unlock ) -(&mm->mmap_sem) +(mm) Signed-off-by: Michel Lespinasse <walken@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Daniel Jordan <daniel.m.jordan@oracle.com> Reviewed-by: Laurent Dufour <ldufour@linux.ibm.com> Reviewed-by: Vlastimil Babka <vbabka@suse.cz> Cc: Davidlohr Bueso <dbueso@suse.de> Cc: David Rientjes <rientjes@google.com> Cc: Hugh Dickins <hughd@google.com> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: Jerome Glisse <jglisse@redhat.com> Cc: John Hubbard <jhubbard@nvidia.com> Cc: Liam Howlett <Liam.Howlett@oracle.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ying Han <yinghan@google.com> Link: http://lkml.kernel.org/r/20200520052908.204642-5-walken@google.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-08net-zerocopy: use vm_insert_pages() for tcp rcv zerocopyArjun Roy
Use vm_insert_pages() for tcp receive zerocopy. Spin lock cycles (as reported by perf) drop from a couple of percentage points to a fraction of a percent. This results in a roughly 6% increase in efficiency, measured roughly as zerocopy receive count divided by CPU utilization. The intention of this patchset is to reduce atomic ops for tcp zerocopy receives, which normally hits the same spinlock multiple times consecutively. [akpm@linux-foundation.org: suppress gcc-7.2.0 warning] Link: http://lkml.kernel.org/r/20200128025958.43490-3-arjunroy.kdev@gmail.com Signed-off-by: Arjun Roy <arjunroy@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Soheil Hassas Yeganeh <soheil@google.com> Cc: David Miller <davem@davemloft.net> Cc: Matthew Wilcox <willy@infradead.org> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-05-28tcp: add tcp_sock_set_keepcntChristoph Hellwig
Add a helper to directly set the TCP_KEEPCNT sockopt from kernel space without going through a fake uaccess. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-05-28tcp: add tcp_sock_set_keepintvlChristoph Hellwig
Add a helper to directly set the TCP_KEEPINTVL sockopt from kernel space without going through a fake uaccess. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-05-28tcp: add tcp_sock_set_keepidleChristoph Hellwig
Add a helper to directly set the TCP_KEEP_IDLE sockopt from kernel space without going through a fake uaccess. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-05-28tcp: add tcp_sock_set_user_timeoutChristoph Hellwig
Add a helper to directly set the TCP_USER_TIMEOUT sockopt from kernel space without going through a fake uaccess. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-05-28tcp: add tcp_sock_set_syncntChristoph Hellwig
Add a helper to directly set the TCP_SYNCNT sockopt from kernel space without going through a fake uaccess. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Sagi Grimberg <sagi@grimberg.me> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-05-28tcp: add tcp_sock_set_quickackChristoph Hellwig
Add a helper to directly set the TCP_QUICKACK sockopt from kernel space without going through a fake uaccess. Cleanup the callers to avoid pointless wrappers now that this is a simple function call. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-05-28tcp: add tcp_sock_set_nodelayChristoph Hellwig
Add a helper to directly set the TCP_NODELAY sockopt from kernel space without going through a fake uaccess. Cleanup the callers to avoid pointless wrappers now that this is a simple function call. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Sagi Grimberg <sagi@grimberg.me> Acked-by: Jason Gunthorpe <jgg@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-05-28tcp: add tcp_sock_set_corkChristoph Hellwig
Add a helper to directly set the TCP_CORK sockopt from kernel space without going through a fake uaccess. Cleanup the callers to avoid pointless wrappers now that this is a simple function call. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-05-15Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netDavid S. Miller
Move the bpf verifier trace check into the new switch statement in HEAD. Resolve the overlapping changes in hinic, where bug fixes overlap the addition of VF support. Signed-off-by: David S. Miller <davem@davemloft.net>
2020-05-14tcp: fix error recovery in tcp_zerocopy_receive()Eric Dumazet
If user provides wrong virtual address in TCP_ZEROCOPY_RECEIVE operation we want to return -EINVAL error. But depending on zc->recv_skip_hint content, we might return -EIO error if the socket has SOCK_DONE set. Make sure to return -EINVAL in this case. BUG: KMSAN: uninit-value in tcp_zerocopy_receive net/ipv4/tcp.c:1833 [inline] BUG: KMSAN: uninit-value in do_tcp_getsockopt+0x4494/0x6320 net/ipv4/tcp.c:3685 CPU: 1 PID: 625 Comm: syz-executor.0 Not tainted 5.7.0-rc4-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1c9/0x220 lib/dump_stack.c:118 kmsan_report+0xf7/0x1e0 mm/kmsan/kmsan_report.c:121 __msan_warning+0x58/0xa0 mm/kmsan/kmsan_instr.c:215 tcp_zerocopy_receive net/ipv4/tcp.c:1833 [inline] do_tcp_getsockopt+0x4494/0x6320 net/ipv4/tcp.c:3685 tcp_getsockopt+0xf8/0x1f0 net/ipv4/tcp.c:3728 sock_common_getsockopt+0x13f/0x180 net/core/sock.c:3131 __sys_getsockopt+0x533/0x7b0 net/socket.c:2177 __do_sys_getsockopt net/socket.c:2192 [inline] __se_sys_getsockopt+0xe1/0x100 net/socket.c:2189 __x64_sys_getsockopt+0x62/0x80 net/socket.c:2189 do_syscall_64+0xb8/0x160 arch/x86/entry/common.c:297 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x45c829 Code: 0d b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 db b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f1deeb72c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000037 RAX: ffffffffffffffda RBX: 00000000004e01e0 RCX: 000000000045c829 RDX: 0000000000000023 RSI: 0000000000000006 RDI: 0000000000000009 RBP: 000000000078bf00 R08: 0000000020000200 R09: 0000000000000000 R10: 00000000200001c0 R11: 0000000000000246 R12: 00000000ffffffff R13: 00000000000001d8 R14: 00000000004d3038 R15: 00007f1deeb736d4 Local variable ----zc@do_tcp_getsockopt created at: do_tcp_getsockopt+0x1a74/0x6320 net/ipv4/tcp.c:3670 do_tcp_getsockopt+0x1a74/0x6320 net/ipv4/tcp.c:3670 Fixes: 05255b823a61 ("tcp: add TCP_ZEROCOPY_RECEIVE support for zerocopy receive") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: syzbot <syzkaller@googlegroups.com> Acked-by: Soheil Hassas Yeganeh <soheil@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-05-12tcp: fix SO_RCVLOWAT hangs with fat skbsEric Dumazet
We autotune rcvbuf whenever SO_RCVLOWAT is set to account for 100% overhead in tcp_set_rcvlowat() This works well when skb->len/skb->truesize ratio is bigger than 0.5 But if we receive packets with small MSS, we can end up in a situation where not enough bytes are available in the receive queue to satisfy RCVLOWAT setting. As our sk_rcvbuf limit is hit, we send zero windows in ACK packets, preventing remote peer from sending more data. Even autotuning does not help, because it only triggers at the time user process drains the queue. If no EPOLLIN is generated, this can not happen. Note poll() has a similar issue, after commit c7004482e8dc ("tcp: Respect SO_RCVLOWAT in tcp_poll().") Fixes: 03f45c883c6f ("tcp: avoid extra wakeups for SO_RCVLOWAT users") Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Soheil Hassas Yeganeh <soheil@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-05-08net: tcp: fix rx timestamp behavior for tcp_recvmsgKelly Littlepage
The stated intent of the original commit is to is to "return the timestamp corresponding to the highest sequence number data returned." The current implementation returns the timestamp for the last byte of the last fully read skb, which is not necessarily the last byte in the recv buffer. This patch converts behavior to the original definition, and to the behavior of the previous draft versions of commit 98aaa913b4ed ("tcp: Extend SOF_TIMESTAMPING_RX_SOFTWARE to TCP recvmsg") which also match this behavior. Fixes: 98aaa913b4ed ("tcp: Extend SOF_TIMESTAMPING_RX_SOFTWARE to TCP recvmsg") Co-developed-by: Iris Liu <iris@onechronos.com> Signed-off-by: Iris Liu <iris@onechronos.com> Signed-off-by: Kelly Littlepage <kelly@onechronos.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Soheil Hassas Yeganeh <soheil@google.com> Acked-by: Willem de Bruijn <willemb@google.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>