Add support to inet v4 raw sockets for binding to nonlocal addresses
through the IP_FREEBIND and IP_TRANSPARENT socket options, as well as
the ipv4.ip_nonlocal_bind kernel parameter.
Add helper function to inet_sock.h to check for bind address validity on
the base of the address type and whether nonlocal address are enabled
for the socket via any of the sockopts/sysctl, deduplicating checks in
ipv4/ping.c, ipv4/af_inet.c, ipv6/af_inet6.c (for mapped v4->v6
addresses), and ipv4/raw.c.
Add test cases with IP[V6]_FREEBIND verifying that both v4 and v6 raw
sockets support binding to nonlocal addresses after the change. Add
necessary support for the test cases to nettest.
Signed-off-by: Riccardo Paolo Bestetti <pbl@bestov.io>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://lore.kernel.org/r/20211117090010.125393-1-pbl@bestov.io
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
siphash keys use 16 bytes.
Define siphash_aligned_key_t macro so that we can make sure they
are not crossing a cache line boundary.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Daniel Borkmann says:
====================
pull-request: bpf 2021-11-16
We've added 12 non-merge commits during the last 5 day(s) which contain
a total of 23 files changed, 573 insertions(+), 73 deletions(-).
The main changes are:
1) Fix pruning regression where verifier went overly conservative rejecting
previsouly accepted programs, from Alexei Starovoitov and Lorenz Bauer.
2) Fix verifier TOCTOU bug when using read-only map's values as constant
scalars during verification, from Daniel Borkmann.
3) Fix a crash due to a double free in XSK's buffer pool, from Magnus Karlsson.
4) Fix libbpf regression when cross-building runqslower, from Jean-Philippe Brucker.
5) Forbid use of bpf_ktime_get_coarse_ns() and bpf_timer_*() helpers in tracing
programs due to deadlock possibilities, from Dmitrii Banshchikov.
6) Fix checksum validation in sockmap's udp_read_sock() callback, from Cong Wang.
7) Various BPF sample fixes such as XDP stats in xdp_sample_user, from Alexander Lobakin.
8) Fix libbpf gen_loader error handling wrt fd cleanup, from Kumar Kartikeya Dwivedi.
* https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf:
udp: Validate checksum in udp_read_sock()
bpf: Fix toctou on read-only map's constant scalar tracking
samples/bpf: Fix build error due to -isystem removal
selftests/bpf: Add tests for restricted helpers
bpf: Forbid bpf_ktime_get_coarse_ns and bpf_timer_* in tracing progs
libbpf: Perform map fd cleanup for gen_loader in case of error
samples/bpf: Fix incorrect use of strlen in xdp_redirect_cpu
tools/runqslower: Fix cross-build
samples/bpf: Fix summary per-sec stats in xdp_sample_user
selftests/bpf: Check map in map pruning
bpf: Fix inner map state pruning regression.
xsk: Fix crash on double free in buffer pool
====================
Link: https://lore.kernel.org/r/20211116141134.6490-1-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
This is distracting really, let's make this simpler,
because many callers had to take care of this
by themselves, even if on x86 this adds more
code than really needed.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This helper is used once, no need to keep it in fat net/core/skbuff.c
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
include/linux/netdevice.h became too big, move gro stuff
into include/net/gro.h
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Under pressure, tcp recvmsg() has logic to process the socket backlog,
but calls tcp_cleanup_rbuf() right before.
Avoiding sending ACK right before processing new segments makes
a lot of sense, as this decrease the number of ACK packets,
with no impact on effective ACK clocking.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Testing timeo before sk_err/sk_state/sk_shutdown makes more sense.
Modern applications use non-blocking IO, while a socket is terminated
only once during its life time.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
tcp recvmsg() (or rx zerocopy) spends a fair amount of time
freeing skbs after their payload has been consumed.
A typical ~64KB GRO packet has to release ~45 page
references, eventually going to page allocator
for each of them.
Currently, this freeing is performed while socket lock
is held, meaning that there is a high chance that
BH handler has to queue incoming packets to tcp socket backlog.
This can cause additional latencies, because the user
thread has to process the backlog at release_sock() time,
and while doing so, additional frames can be added
by BH handler.
This patch adds logic to defer these frees after socket
lock is released, or directly from BH handler if possible.
Being able to free these skbs from BH handler helps a lot,
because this avoids the usual alloc/free assymetry,
when BH handler and user thread do not run on same cpu or
NUMA node.
One cpu can now be fully utilized for the kernel->user copy,
and another cpu is handling BH processing and skb/page
allocs/frees (assuming RFS is not forcing use of a single CPU)
Tested:
100Gbit NIC
Max throughput for one TCP_STREAM flow, over 10 runs
MTU : 1500
Before: 55 Gbit
After: 66 Gbit
MTU : 4096+(headers)
Before: 82 Gbit
After: 95 Gbit
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
TCP uses sk_eat_skb() when skbs can be removed from receive queue.
However, the call to skb_orphan() from __kfree_skb() incurs
an indirect call so sock_rfee(), which is more expensive than
a direct call, especially for CONFIG_RETPOLINE=y.
Add tcp_eat_recv_skb() function to make the call before
__kfree_skb().
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
tcp_poll() and tcp_ioctl() are reading tp->urg_data without socket lock
owned.
Also, it is faster to first check tp->urg_data in tcp_poll(),
then tp->urg_seq == tp->copied_seq, because tp->urg_seq is
located in a different/cold cache line.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
tcp_segs_in() can be called from BH, while socket spinlock
is held but socket owned by user, eventually reading these
fields from tcp_get_info()
Found by code inspection, no need to backport this patch
to older kernels.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When reading large chunks of data, incoming packets might
be added to the backlog from BH.
tcp recvmsg() detects the backlog queue is not empty, and uses
a release_sock()/lock_sock() pair to process this backlog.
We now have __sk_flush_backlog() to perform this
a bit faster.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
tcp_memory_allocated and tcp_sockets_allocated often share
a common cache line, source of false sharing.
Also take care of udp_memory_allocated and mptcp_sockets_allocated.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Instead of using a full netdev_features_t, we can use a single bit,
as sk_route_nocaps is only used to remove NETIF_F_GSO_MASK from
sk->sk_route_cap.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
We were only using one bit, and we can replace it by sk_is_tcp()
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
If packet is going to be coalesced, sk_sndbuf/sk_rcvbuf values
are not used. Defer their access to the point we need them.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
It turns out the skb's in sock receive queue could have bad checksums, as
both ->poll() and ->recvmsg() validate checksums. We have to do the same
for ->read_sock() path too before they are redirected in sockmap.
Fixes: d7f571188ecf ("udp: Implement ->read_sock() for sockmap")
Reported-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Cong Wang <cong.wang@bytedance.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20211115044006.26068-1-xiyou.wangcong@gmail.com
Daniel Borkmann says:
====================
pull-request: bpf-next 2021-11-15
We've added 72 non-merge commits during the last 13 day(s) which contain
a total of 171 files changed, 2728 insertions(+), 1143 deletions(-).
The main changes are:
1) Add btf_type_tag attributes to bring kernel annotations like __user/__rcu to
BTF such that BPF verifier will be able to detect misuse, from Yonghong Song.
2) Big batch of libbpf improvements including various fixes, future proofing APIs,
and adding a unified, OPTS-based bpf_prog_load() low-level API, from Andrii Nakryiko.
3) Add ingress_ifindex to BPF_SK_LOOKUP program type for selectively applying the
programmable socket lookup logic to packets from a given netdev, from Mark Pashmfouroush.
4) Remove the 128M upper JIT limit for BPF programs on arm64 and add selftest to
ensure exception handling still works, from Russell King and Alan Maguire.
5) Add a new bpf_find_vma() helper for tracing to map an address to the backing
file such as shared library, from Song Liu.
6) Batch of various misc fixes to bpftool, fixing a memory leak in BPF program dump,
updating documentation and bash-completion among others, from Quentin Monnet.
7) Deprecate libbpf bpf_program__get_prog_info_linear() API and migrate its users as
the API is heavily tailored around perf and is non-generic, from Dave Marchevsky.
8) Enable libbpf's strict mode by default in bpftool and add a --legacy option as an
opt-out for more relaxed BPF program requirements, from Stanislav Fomichev.
9) Fix bpftool to use libbpf_get_error() to check for errors, from Hengqi Chen.
* https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (72 commits)
bpftool: Use libbpf_get_error() to check error
bpftool: Fix mixed indentation in documentation
bpftool: Update the lists of names for maps and prog-attach types
bpftool: Fix indent in option lists in the documentation
bpftool: Remove inclusion of utilities.mak from Makefiles
bpftool: Fix memory leak in prog_dump()
selftests/bpf: Fix a tautological-constant-out-of-range-compare compiler warning
selftests/bpf: Fix an unused-but-set-variable compiler warning
bpf: Introduce btf_tracing_ids
bpf: Extend BTF_ID_LIST_GLOBAL with parameter for number of IDs
bpftool: Enable libbpf's strict mode by default
docs/bpf: Update documentation for BTF_KIND_TYPE_TAG support
selftests/bpf: Clarify llvm dependency with btf_tag selftest
selftests/bpf: Add a C test for btf_type_tag
selftests/bpf: Rename progs/tag.c to progs/btf_decl_tag.c
selftests/bpf: Test BTF_KIND_DECL_TAG for deduplication
selftests/bpf: Add BTF_KIND_TYPE_TAG unit tests
selftests/bpf: Test libbpf API function btf__add_type_tag()
bpftool: Support BTF_KIND_TYPE_TAG
libbpf: Support BTF_KIND_TYPE_TAG
...
====================
Link: https://lore.kernel.org/r/20211115162008.25916-1-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
When kmemdup called failed and register_net_sysctl return NULL, should
return ENOMEM instead of ENOBUFS
Signed-off-by: liuguoqiang <liuguoqiang@uniontech.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
there is a same action when the variable is initialized
Reported-by: Zeal Robot <zealci@zte.com.cn>
Signed-off-by: luo penghao <luo.penghao@zte.com.cn>
Signed-off-by: David S. Miller <davem@davemloft.net>
The assignment in the if statement will be overwritten by the
following statement
Reported-by: Zeal Robot <zealci@zte.com.cn>
Signed-off-by: luo penghao <luo.penghao@zte.com.cn>
Signed-off-by: David S. Miller <davem@davemloft.net>
TCP Receive zerocopy iterates through the SKB queue via
tcp_recv_skb(), acquiring a pointer to an SKB and an offset within
that SKB to read from. From there, it iterates the SKB frags array to
determine which offset to start remapping pages from.
However, this is built on the assumption that the offset read so far
within the SKB is smaller than the SKB length. If this assumption is
violated, we can attempt to read an invalid frags array element, which
would cause a fault.
tcp_recv_skb() can cause such an SKB to be returned when the TCP FIN
flag is set. Therefore, we must guard against this occurrence inside
skb_advance_frag().
One way that we can reproduce this error follows:
1) In a receiver program, call getsockopt(TCP_ZEROCOPY_RECEIVE) with:
char some_array[32 * 1024];
struct tcp_zerocopy_receive zc = {
.copybuf_address = (__u64) &some_array[0],
.copybuf_len = 32 * 1024,
};
2) In a sender program, after a TCP handshake, send the following
sequence of packets:
i) Seq = [X, X+4000]
ii) Seq = [X+4000, X+5000]
iii) Seq = [X+4000, X+5000], Flags = FIN | URG, urgptr=1000
(This can happen without URG, if we have a signal pending, but URG is
a convenient way to reproduce the behaviour).
In this case, the following event sequence will occur on the receiver:
tcp_zerocopy_receive():
-> receive_fallback_to_copy() // copybuf_len >= inq
-> tcp_recvmsg_locked() // reads 5000 bytes, then breaks due to URG
-> tcp_recv_skb() // yields skb with skb->len == offset
-> tcp_zerocopy_set_hint_for_skb()
-> skb_advance_to_frag() // will returns a frags ptr. >= nr_frags
-> find_next_mappable_frag() // will dereference this bad frags ptr.
With this patch, skb_advance_to_frag() will no longer return an
invalid frags pointer, and will return NULL instead, fixing the issue.
Signed-off-by: Arjun Roy <arjunroy@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Fixes: 05255b823a61 ("tcp: add TCP_ZEROCOPY_RECEIVE support for zerocopy receive")
Link: https://lore.kernel.org/r/20211111235215.2605384-1-arjunroy.kdev@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
and netfilter.
Current release - regressions:
- bpf: do not reject when the stack read size is different
from the tracked scalar size
- net: fix premature exit from NAPI state polling in napi_disable()
- riscv, bpf: fix RV32 broken build, and silence RV64 warning
Current release - new code bugs:
- net: fix possible NULL deref in sock_reserve_memory
- amt: fix error return code in amt_init(); fix stopping the workqueue
- ax88796c: use the correct ioctl callback
Previous releases - always broken:
- bpf: stop caching subprog index in the bpf_pseudo_func insn
- security: fixups for the security hooks in sctp
- nfc: add necessary privilege flags in netlink layer, limit operations
to admin only
- vsock: prevent unnecessary refcnt inc for non-blocking connect
- net/smc: fix sk_refcnt underflow on link down and fallback
- nfnetlink_queue: fix OOB when mac header was cleared
- can: j1939: ignore invalid messages per standard
- bpf, sockmap:
- fix race in ingress receive verdict with redirect to self
- fix incorrect sk_skb data_end access when src_reg = dst_reg
- strparser, and tls are reusing qdisc_skb_cb and colliding
- ethtool: fix ethtool msg len calculation for pause stats
- vlan: fix a UAF in vlan_dev_real_dev() when ref-holder tries
to access an unregistering real_dev
- udp6: make encap_rcv() bump the v6 not v4 stats
- drv: prestera: add explicit padding to fix m68k build
- drv: felix: fix broken VLAN-tagged PTP under VLAN-aware bridge
- drv: mvpp2: fix wrong SerDes reconfiguration order
Misc & small latecomers:
- ipvs: auto-load ipvs on genl access
- mctp: sanity check the struct sockaddr_mctp padding fields
- libfs: support RENAME_EXCHANGE in simple_rename()
- avoid double accounting for pure zerocopy skbs
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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Merge tag 'net-5.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Pull networking fixes from Jakub Kicinski:
"Including fixes from bpf, can and netfilter.
Current release - regressions:
- bpf: do not reject when the stack read size is different from the
tracked scalar size
- net: fix premature exit from NAPI state polling in napi_disable()
- riscv, bpf: fix RV32 broken build, and silence RV64 warning
Current release - new code bugs:
- net: fix possible NULL deref in sock_reserve_memory
- amt: fix error return code in amt_init(); fix stopping the
workqueue
- ax88796c: use the correct ioctl callback
Previous releases - always broken:
- bpf: stop caching subprog index in the bpf_pseudo_func insn
- security: fixups for the security hooks in sctp
- nfc: add necessary privilege flags in netlink layer, limit
operations to admin only
- vsock: prevent unnecessary refcnt inc for non-blocking connect
- net/smc: fix sk_refcnt underflow on link down and fallback
- nfnetlink_queue: fix OOB when mac header was cleared
- can: j1939: ignore invalid messages per standard
- bpf, sockmap:
- fix race in ingress receive verdict with redirect to self
- fix incorrect sk_skb data_end access when src_reg = dst_reg
- strparser, and tls are reusing qdisc_skb_cb and colliding
- ethtool: fix ethtool msg len calculation for pause stats
- vlan: fix a UAF in vlan_dev_real_dev() when ref-holder tries to
access an unregistering real_dev
- udp6: make encap_rcv() bump the v6 not v4 stats
- drv: prestera: add explicit padding to fix m68k build
- drv: felix: fix broken VLAN-tagged PTP under VLAN-aware bridge
- drv: mvpp2: fix wrong SerDes reconfiguration order
Misc & small latecomers:
- ipvs: auto-load ipvs on genl access
- mctp: sanity check the struct sockaddr_mctp padding fields
- libfs: support RENAME_EXCHANGE in simple_rename()
- avoid double accounting for pure zerocopy skbs"
* tag 'net-5.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (123 commits)
selftests/net: udpgso_bench_rx: fix port argument
net: wwan: iosm: fix compilation warning
cxgb4: fix eeprom len when diagnostics not implemented
net: fix premature exit from NAPI state polling in napi_disable()
net/smc: fix sk_refcnt underflow on linkdown and fallback
net/mlx5: Lag, fix a potential Oops with mlx5_lag_create_definer()
gve: fix unmatched u64_stats_update_end()
net: ethernet: lantiq_etop: Fix compilation error
selftests: forwarding: Fix packet matching in mirroring selftests
vsock: prevent unnecessary refcnt inc for nonblocking connect
net: marvell: mvpp2: Fix wrong SerDes reconfiguration order
net: ethernet: ti: cpsw_ale: Fix access to un-initialized memory
net: stmmac: allow a tc-taprio base-time of zero
selftests: net: test_vxlan_under_vrf: fix HV connectivity test
net: hns3: allow configure ETS bandwidth of all TCs
net: hns3: remove check VF uc mac exist when set by PF
net: hns3: fix some mac statistics is always 0 in device version V2
net: hns3: fix kernel crash when unload VF while it is being reset
net: hns3: sync rx ring head in echo common pull
net: hns3: fix pfc packet number incorrect after querying pfc parameters
...
It may be helpful to have access to the ifindex during bpf socket
lookup. An example may be to scope certain socket lookup logic to
specific interfaces, i.e. an interface may be made exempt from custom
lookup code.
Add the ifindex of the arriving connection to the bpf_sk_lookup API.
Signed-off-by: Mark Pashmfouroush <markpash@cloudflare.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20211110111016.5670-2-markpash@cloudflare.com
A socket in a sockmap may have different combinations of programs attached
depending on configuration. There can be no programs in which case the socket
acts as a sink only. There can be a TX program in this case a BPF program is
attached to sending side, but no RX program is attached. There can be an RX
program only where sends have no BPF program attached, but receives are hooked
with BPF. And finally, both TX and RX programs may be attached. Giving us the
permutations:
None, Tx, Rx, and TxRx
To date most of our use cases have been TX case being used as a fast datapath
to directly copy between local application and a userspace proxy. Or Rx cases
and TxRX applications that are operating an in kernel based proxy. The traffic
in the first case where we hook applications into a userspace application looks
like this:
AppA redirect AppB
Tx <-----------> Rx
| |
+ +
TCP <--> lo <--> TCP
In this case all traffic from AppA (after 3whs) is copied into the AppB
ingress queue and no traffic is ever on the TCP recieive_queue.
In the second case the application never receives, except in some rare error
cases, traffic on the actual user space socket. Instead the send happens in
the kernel.
AppProxy socket pool
sk0 ------------->{sk1,sk2, skn}
^ |
| |
| v
ingress lb egress
TCP TCP
Here because traffic is never read off the socket with userspace recv() APIs
there is only ever one reader on the sk receive_queue. Namely the BPF programs.
However, we've started to introduce a third configuration where the BPF program
on receive should process the data, but then the normal case is to push the
data into the receive queue of AppB.
AppB
recv() (userspace)
-----------------------
tcp_bpf_recvmsg() (kernel)
| |
| |
| |
ingress_msgQ |
| |
RX_BPF |
| |
v v
sk->receive_queue
This is different from the App{A,B} redirect because traffic is first received
on the sk->receive_queue.
Now for the issue. The tcp_bpf_recvmsg() handler first checks the ingress_msg
queue for any data handled by the BPF rx program and returned with PASS code
so that it was enqueued on the ingress msg queue. Then if no data exists on
that queue it checks the socket receive queue. Unfortunately, this is the same
receive_queue the BPF program is reading data off of. So we get a race. Its
possible for the recvmsg() hook to pull data off the receive_queue before the
BPF hook has a chance to read it. It typically happens when an application is
banging on recv() and getting EAGAINs. Until they manage to race with the RX
BPF program.
To fix this we note that before this patch at attach time when the socket is
loaded into the map we check if it needs a TX program or just the base set of
proto bpf hooks. Then it uses the above general RX hook regardless of if we
have a BPF program attached at rx or not. This patch now extends this check to
handle all cases enumerated above, TX, RX, TXRX, and none. And to fix above
race when an RX program is attached we use a new hook that is nearly identical
to the old one except now we do not let the recv() call skip the RX BPF program.
Now only the BPF program pulls data from sk->receive_queue and recv() only
pulls data from the ingress msgQ post BPF program handling.
With this resolved our AppB from above has been up and running for many hours
without detecting any errors. We do this by correlating counters in RX BPF
events and the AppB to ensure data is never skipping the BPF program. Selftests,
was not able to detect this because we only run them for a short period of time
on well ordered send/recvs so we don't get any of the noise we see in real
application environments.
Fixes: 51199405f9672 ("bpf: skb_verdict, support SK_PASS on RX BPF path")
Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Tested-by: Jussi Maki <joamaki@gmail.com>
Reviewed-by: Jakub Sitnicki <jakub@cloudflare.com>
Link: https://lore.kernel.org/bpf/20211103204736.248403-4-john.fastabend@gmail.com
We do not need to handle unhash from BPF side we can simply wait for the
close to happen. The original concern was a socket could transition from
ESTABLISHED state to a new state while the BPF hook was still attached.
But, we convinced ourself this is no longer possible and we also improved
BPF sockmap to handle listen sockets so this is no longer a problem.
More importantly though there are cases where unhash is called when data is
in the receive queue. The BPF unhash logic will flush this data which is
wrong. To be correct it should keep the data in the receive queue and allow
a receiving application to continue reading the data. This may happen when
tcp_abort() is received for example. Instead of complicating the logic in
unhash simply moving all this to tcp_close() hook solves this.
Fixes: 51199405f9672 ("bpf: skb_verdict, support SK_PASS on RX BPF path")
Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Tested-by: Jussi Maki <joamaki@gmail.com>
Reviewed-by: Jakub Sitnicki <jakub@cloudflare.com>
Link: https://lore.kernel.org/bpf/20211103204736.248403-3-john.fastabend@gmail.com
Merge misc updates from Andrew Morton:
"257 patches.
Subsystems affected by this patch series: scripts, ocfs2, vfs, and
mm (slab-generic, slab, slub, kconfig, dax, kasan, debug, pagecache,
gup, swap, memcg, pagemap, mprotect, mremap, iomap, tracing, vmalloc,
pagealloc, memory-failure, hugetlb, userfaultfd, vmscan, tools,
memblock, oom-kill, hugetlbfs, migration, thp, readahead, nommu, ksm,
vmstat, madvise, memory-hotplug, rmap, zsmalloc, highmem, zram,
cleanups, kfence, and damon)"
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (257 commits)
mm/damon: remove return value from before_terminate callback
mm/damon: fix a few spelling mistakes in comments and a pr_debug message
mm/damon: simplify stop mechanism
Docs/admin-guide/mm/pagemap: wordsmith page flags descriptions
Docs/admin-guide/mm/damon/start: simplify the content
Docs/admin-guide/mm/damon/start: fix a wrong link
Docs/admin-guide/mm/damon/start: fix wrong example commands
mm/damon/dbgfs: add adaptive_targets list check before enable monitor_on
mm/damon: remove unnecessary variable initialization
Documentation/admin-guide/mm/damon: add a document for DAMON_RECLAIM
mm/damon: introduce DAMON-based Reclamation (DAMON_RECLAIM)
selftests/damon: support watermarks
mm/damon/dbgfs: support watermarks
mm/damon/schemes: activate schemes based on a watermarks mechanism
tools/selftests/damon: update for regions prioritization of schemes
mm/damon/dbgfs: support prioritization weights
mm/damon/vaddr,paddr: support pageout prioritization
mm/damon/schemes: prioritize regions within the quotas
mm/damon/selftests: support schemes quotas
mm/damon/dbgfs: support quotas of schemes
...
nr_free_buffer_pages could be exposed through mm.h instead of swap.h.
The advantage of this change is that it can reduce the obsolete
includes. For example, net/ipv4/tcp.c wouldn't need swap.h any more
since it has already included mm.h. Similarly, after checking all the
other files, it comes that tcp.c, udp.c meter.c ,... follow the same
rule, so these files can have swap.h removed too.
Moreover, after preprocessing all the files that use
nr_free_buffer_pages, it turns out that those files have already
included mm.h.Thus, we can move nr_free_buffer_pages from swap.h to mm.h
safely. This change will not affect the compilation of other files.
Link: https://lkml.kernel.org/r/20210912133640.1624-1-liumh1@shanghaitech.edu.cn
Signed-off-by: Mianhan Liu <liumh1@shanghaitech.edu.cn>
Cc: Jakub Kicinski <kuba@kernel.org>
CC: Ulf Hansson <ulf.hansson@linaro.org>
Cc: "David S . Miller" <davem@davemloft.net>
Cc: Simon Horman <horms@verge.net.au>
Cc: Pravin B Shelar <pshelar@ovn.org>
Cc: Vlad Yasevich <vyasevich@gmail.com>
Cc: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Cc: Matthew Wilcox <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Extending these flags using the existing (1 << x) pattern triggers
complaints from checkpatch. Instead of ignoring checkpatch modify the
existing values to use BIT(x) style in a separate commit.
Signed-off-by: Leonard Crestez <cdleonard@gmail.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Track skbs containing only zerocopy data and avoid charging them to
kernel memory to correctly account the memory utilization for
msg_zerocopy. All of the data in such skbs is held in user pages which
are already accounted to user. Before this change, they are charged
again in kernel in __zerocopy_sg_from_iter. The charging in kernel is
excessive because data is not being copied into skb frags. This
excessive charging can lead to kernel going into memory pressure
state which impacts all sockets in the system adversely. Mark pure
zerocopy skbs with a SKBFL_PURE_ZEROCOPY flag and remove
charge/uncharge for data in such skbs.
Initially, an skb is marked pure zerocopy when it is empty and in
zerocopy path. skb can then change from a pure zerocopy skb to mixed
data skb (zerocopy and copy data) if it is at tail of write queue and
there is room available in it and non-zerocopy data is being sent in
the next sendmsg call. At this time sk_mem_charge is done for the pure
zerocopied data and the pure zerocopy flag is unmarked. We found that
this happens very rarely on workloads that pass MSG_ZEROCOPY.
A pure zerocopy skb can later be coalesced into normal skb if they are
next to each other in queue but this patch prevents coalescing from
happening. This avoids complexity of charging when skb downgrades from
pure zerocopy to mixed. This is also rare.
In sk_wmem_free_skb, if it is a pure zerocopy skb, an sk_mem_uncharge
for SKB_TRUESIZE(skb_end_offset(skb)) is done for sk_mem_charge in
tcp_skb_entail for an skb without data.
Testing with the msg_zerocopy.c benchmark between two hosts(100G nics)
with zerocopy showed that before this patch the 'sock' variable in
memory.stat for cgroup2 that tracks sum of sk_forward_alloc,
sk_rmem_alloc and sk_wmem_queued is around 1822720 and with this
change it is 0. This is due to no charge to sk_forward_alloc for
zerocopy data and shows memory utilization for kernel is lowered.
With this commit we don't see the warning we saw in previous commit
which resulted in commit 84882cf72cd774cf16fd338bdbf00f69ac9f9194.
Signed-off-by: Talal Ahmad <talalahmad@google.com>
Acked-by: Arjun Roy <arjunroy@google.com>
Acked-by: Soheil Hassas Yeganeh <soheil@google.com>
Signed-off-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
While commit 097b9146c0e2 ("net: fix up truesize of cloned
skb in skb_prepare_for_shift()") fixed immediate issues found
when KFENCE was enabled/tested, there are still similar issues,
when tcp_trim_head() hits KFENCE while the master skb
is cloned.
This happens under heavy networking TX workloads,
when the TX completion might be delayed after incoming ACK.
This patch fixes the WARNING in sk_stream_kill_queues
when sk->sk_mem_queued/sk->sk_forward_alloc are not zero.
Fixes: d3fb45f370d9 ("mm, kfence: insert KFENCE hooks for SLAB")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Marco Elver <elver@google.com>
Link: https://lore.kernel.org/r/20211102004555.1359210-1-eric.dumazet@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Alexei Starovoitov says:
====================
pull-request: bpf-next 2021-11-01
We've added 181 non-merge commits during the last 28 day(s) which contain
a total of 280 files changed, 11791 insertions(+), 5879 deletions(-).
The main changes are:
1) Fix bpf verifier propagation of 64-bit bounds, from Alexei.
2) Parallelize bpf test_progs, from Yucong and Andrii.
3) Deprecate various libbpf apis including af_xdp, from Andrii, Hengqi, Magnus.
4) Improve bpf selftests on s390, from Ilya.
5) bloomfilter bpf map type, from Joanne.
6) Big improvements to JIT tests especially on Mips, from Johan.
7) Support kernel module function calls from bpf, from Kumar.
8) Support typeless and weak ksym in light skeleton, from Kumar.
9) Disallow unprivileged bpf by default, from Pawan.
10) BTF_KIND_DECL_TAG support, from Yonghong.
11) Various bpftool cleanups, from Quentin.
* https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (181 commits)
libbpf: Deprecate AF_XDP support
kbuild: Unify options for BTF generation for vmlinux and modules
selftests/bpf: Add a testcase for 64-bit bounds propagation issue.
bpf: Fix propagation of signed bounds from 64-bit min/max into 32-bit.
bpf: Fix propagation of bounds from 64-bit min/max into 32-bit and var_off.
selftests/bpf: Fix also no-alu32 strobemeta selftest
bpf: Add missing map_delete_elem method to bloom filter map
selftests/bpf: Add bloom map success test for userspace calls
bpf: Add alignment padding for "map_extra" + consolidate holes
bpf: Bloom filter map naming fixups
selftests/bpf: Add test cases for struct_ops prog
bpf: Add dummy BPF STRUCT_OPS for test purpose
bpf: Factor out helpers for ctx access checking
bpf: Factor out a helper to prepare trampoline for struct_ops prog
selftests, bpf: Fix broken riscv build
riscv, libbpf: Add RISC-V (RV64) support to bpf_tracing.h
tools, build: Add RISC-V to HOSTARCH parsing
riscv, bpf: Increase the maximum number of iterations
selftests, bpf: Add one test for sockmap with strparser
selftests, bpf: Fix test_txmsg_ingress_parser error
...
====================
Link: https://lore.kernel.org/r/20211102013123.9005-1-alexei.starovoitov@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
This change introduces a new sysctl parameter, arp_evict_nocarrier.
When set (default) the ARP cache will be cleared on a NOCARRIER event.
This new option has been defaulted to '1' which maintains existing
behavior.
Clearing the ARP cache on NOCARRIER is relatively new, introduced by:
commit 859bd2ef1fc1110a8031b967ee656c53a6260a76
Author: David Ahern <dsahern@gmail.com>
Date: Thu Oct 11 20:33:49 2018 -0700
net: Evict neighbor entries on carrier down
The reason for this changes is to prevent the ARP cache from being
cleared when a wireless device roams. Specifically for wireless roams
the ARP cache should not be cleared because the underlying network has not
changed. Clearing the ARP cache in this case can introduce significant
delays sending out packets after a roam.
A user reported such a situation here:
https://lore.kernel.org/linux-wireless/CACsRnHWa47zpx3D1oDq9JYnZWniS8yBwW1h0WAVZ6vrbwL_S0w@mail.gmail.com/
After some investigation it was found that the kernel was holding onto
packets until ARP finished which resulted in this 1 second delay. It
was also found that the first ARP who-has was never responded to,
which is actually what caues the delay. This change is more or less
working around this behavior, but again, there is no reason to clear
the cache on a roam anyways.
As for the unanswered who-has, we know the packet made it OTA since
it was seen while monitoring. Why it never received a response is
unknown. In any case, since this is a problem on the AP side of things
all that can be done is to work around it until it is solved.
Some background on testing/reproducing the packet delay:
Hardware:
- 2 access points configured for Fast BSS Transition (Though I don't
see why regular reassociation wouldn't have the same behavior)
- Wireless station running IWD as supplicant
- A device on network able to respond to pings (I used one of the APs)
Procedure:
- Connect to first AP
- Ping once to establish an ARP entry
- Start a tcpdump
- Roam to second AP
- Wait for operstate UP event, and note the timestamp
- Start pinging
Results:
Below is the tcpdump after UP. It was recorded the interface went UP at
10:42:01.432875.
10:42:01.461871 ARP, Request who-has 192.168.254.1 tell 192.168.254.71, length 28
10:42:02.497976 ARP, Request who-has 192.168.254.1 tell 192.168.254.71, length 28
10:42:02.507162 ARP, Reply 192.168.254.1 is-at ac:86:74:55:b0:20, length 46
10:42:02.507185 IP 192.168.254.71 > 192.168.254.1: ICMP echo request, id 52792, seq 1, length 64
10:42:02.507205 IP 192.168.254.71 > 192.168.254.1: ICMP echo request, id 52792, seq 2, length 64
10:42:02.507212 IP 192.168.254.71 > 192.168.254.1: ICMP echo request, id 52792, seq 3, length 64
10:42:02.507219 IP 192.168.254.71 > 192.168.254.1: ICMP echo request, id 52792, seq 4, length 64
10:42:02.507225 IP 192.168.254.71 > 192.168.254.1: ICMP echo request, id 52792, seq 5, length 64
10:42:02.507232 IP 192.168.254.71 > 192.168.254.1: ICMP echo request, id 52792, seq 6, length 64
10:42:02.515373 IP 192.168.254.1 > 192.168.254.71: ICMP echo reply, id 52792, seq 1, length 64
10:42:02.521399 IP 192.168.254.1 > 192.168.254.71: ICMP echo reply, id 52792, seq 2, length 64
10:42:02.521612 IP 192.168.254.1 > 192.168.254.71: ICMP echo reply, id 52792, seq 3, length 64
10:42:02.521941 IP 192.168.254.1 > 192.168.254.71: ICMP echo reply, id 52792, seq 4, length 64
10:42:02.522419 IP 192.168.254.1 > 192.168.254.71: ICMP echo reply, id 52792, seq 5, length 64
10:42:02.523085 IP 192.168.254.1 > 192.168.254.71: ICMP echo reply, id 52792, seq 6, length 64
You can see the first ARP who-has went out very quickly after UP, but
was never responded to. Nearly a second later the kernel retries and
gets a response. Only then do the ping packets go out. If an ARP entry
is manually added prior to UP (after the cache is cleared) it is seen
that the first ping is never responded to, so its not only an issue with
ARP but with data packets in general.
As mentioned prior, the wireless interface was also monitored to verify
the ping/ARP packet made it OTA which was observed to be true.
Signed-off-by: James Prestwood <prestwoj@gmail.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Track skbs with only zerocopy data and avoid charging them to kernel
memory to correctly account the memory utilization for msg_zerocopy.
All of the data in such skbs is held in user pages which are already
accounted to user. Before this change, they are charged again in
kernel in __zerocopy_sg_from_iter. The charging in kernel is
excessive because data is not being copied into skb frags. This
excessive charging can lead to kernel going into memory pressure
state which impacts all sockets in the system adversely. Mark pure
zerocopy skbs with a SKBFL_PURE_ZEROCOPY flag and remove
charge/uncharge for data in such skbs.
Initially, an skb is marked pure zerocopy when it is empty and in
zerocopy path. skb can then change from a pure zerocopy skb to mixed
data skb (zerocopy and copy data) if it is at tail of write queue and
there is room available in it and non-zerocopy data is being sent in
the next sendmsg call. At this time sk_mem_charge is done for the pure
zerocopied data and the pure zerocopy flag is unmarked. We found that
this happens very rarely on workloads that pass MSG_ZEROCOPY.
A pure zerocopy skb can later be coalesced into normal skb if they are
next to each other in queue but this patch prevents coalescing from
happening. This avoids complexity of charging when skb downgrades from
pure zerocopy to mixed. This is also rare.
In sk_wmem_free_skb, if it is a pure zerocopy skb, an sk_mem_uncharge
for SKB_TRUESIZE(MAX_TCP_HEADER) is done for sk_mem_charge in
tcp_skb_entail for an skb without data.
Testing with the msg_zerocopy.c benchmark between two hosts(100G nics)
with zerocopy showed that before this patch the 'sock' variable in
memory.stat for cgroup2 that tracks sum of sk_forward_alloc,
sk_rmem_alloc and sk_wmem_queued is around 1822720 and with this
change it is 0. This is due to no charge to sk_forward_alloc for
zerocopy data and shows memory utilization for kernel is lowered.
Signed-off-by: Talal Ahmad <talalahmad@google.com>
Acked-by: Arjun Roy <arjunroy@google.com>
Acked-by: Soheil Hassas Yeganeh <soheil@google.com>
Signed-off-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
sk_wmem_free_skb() is only used by TCP.
Rename it to make this clear, and move its declaration to
include/net/tcp.h
Signed-off-by: Talal Ahmad <talalahmad@google.com>
Acked-by: Soheil Hassas Yeganeh <soheil@google.com>
Acked-by: Arjun Roy <arjunroy@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Factor out two helpers to check the read access of ctx for raw tp
and BTF function. bpf_tracing_ctx_access() is used to check
the read access to argument is valid, and bpf_tracing_btf_ctx_access()
checks whether the btf type of argument is valid besides the checking
of argument read. bpf_tracing_btf_ctx_access() will be used by the
following patch.
Signed-off-by: Hou Tao <houtao1@huawei.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20211025064025.2567443-3-houtao1@huawei.com
Steffen Klassert says:
====================
pull request (net-next): ipsec-next 2021-10-30
Just two minor changes this time:
1) Remove some superfluous header files from xfrm4_tunnel.c
From Mianhan Liu.
2) Simplify some error checks in xfrm_input().
From luo penghao.
Please pull or let me know if there are problems.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
While waiting for a carrier to come on one of the netdevices, some
devices will require to take the rtnl lock at some point to fully
initialize all parts of the link.
That's the case for SFP, where the rtnl is taken when a module gets
detected. This prevents mounting an NFS rootfs over an SFP link.
This means that while ipconfig waits for carriers to be detected, no SFP
modules can be detected in the meantime, it's only detected after
ipconfig times out.
This commit releases the rtnl_lock while waiting for the carrier to come
up, and re-takes it to check the for the init device and carrier status.
Signed-off-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Freshly allocated skbs have zero in skb->cb[] already.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Freshly allocated skbs have their csum field cleared already.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Setting skb->ip_summed to CHECKSUM_PARTIAL can be centralized
in tcp_stream_alloc_skb() and __mptcp_do_alloc_tx_skb()
instead of being done multiple times.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
TCP/MPTCP sendmsg() no longer puts payload in skb->head,
we can remove not needed code.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
TCP sendmsg() no longer puts payload in skb->head,
remove some dead code from tcp_collapse_retrans().
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
All tcp_remove_empty_skb() callers now use tcp_write_queue_tail()
for the skb argument, we can therefore factorize code.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
