Since the udp memory accounting refactor, we don't need any more
to export the *udp*_queue_rcv_skb(). Make them static and fix
a couple of sparse warnings:
net/ipv4/udp.c:1615:5: warning: symbol 'udp_queue_rcv_skb' was not
declared. Should it be static?
net/ipv6/udp.c:572:5: warning: symbol 'udpv6_queue_rcv_skb' was not
declared. Should it be static?
Fixes: 850cbaddb5 ("udp: use it's own memory accounting schema")
Fixes: c915fe13cb ("udplite: fix NULL pointer dereference")
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The conflict was an interaction between a bug fix in the
netvsc driver in 'net' and an optimization of the RX path
in 'net-next'.
Signed-off-by: David S. Miller <davem@davemloft.net>
When same struct dst_entry can be used for many different
neighbours we can not use it for pending confirmations.
The datagram protocols can use MSG_CONFIRM to confirm the
neighbour. When used with MSG_PROBE we do not reach the
code where neighbour is confirmed, so we have to do the
same slow lookup by using the dst_confirm_neigh() helper.
When MSG_PROBE is not used, ip_append_data/ip6_append_data
will set the skb flag dst_pending_confirm.
Reported-by: YueHaibing <yuehaibing@huawei.com>
Fixes: 5110effee8 ("net: Do delayed neigh confirmation.")
Fixes: f2bb4bedf3 ("ipv4: Cache output routes in fib_info nexthops.")
Signed-off-by: Julian Anastasov <ja@ssi.bg>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Dmitry reported that UDP sockets being destroyed would trigger the
WARN_ON(atomic_read(&sk->sk_rmem_alloc)); in inet_sock_destruct()
It turns out we do not properly destroy skb(s) that have wrong UDP
checksum.
Thanks again to syzkaller team.
Fixes : 7c13f97ffd ("udp: do fwd memory scheduling on dequeue")
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Paolo Abeni <pabeni@redhat.com>
Cc: Hannes Frederic Sowa <hannes@stressinduktion.org>
Acked-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Packets arriving in a VRF currently are delivered to UDP sockets that
aren't bound to any interface. TCP defaults to not delivering packets
arriving in a VRF to unbound sockets. IP route lookup and socket
transmit both assume that unbound means using the default table and
UDP applications that haven't been changed to be aware of VRFs may not
function correctly in this case since they may not be able to handle
overlapping IP address ranges, or be able to send packets back to the
original sender if required.
So add a sysctl, udp_l3mdev_accept, to control this behaviour with it
being analgous to the existing tcp_l3mdev_accept, namely to allow a
process to have a VRF-global listen socket. Have this default to off
as this is the behaviour that users will expect, given that there is
no explicit mechanism to set unmodified VRF-unaware application into a
default VRF.
Signed-off-by: Robert Shearman <rshearma@brocade.com>
Acked-by: David Ahern <dsa@cumulusnetworks.com>
Tested-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
We pass these per-protocol equal functions around in various places, but
we can just have one function that checks the sk->sk_family and then do
the right comparison function. I've also changed the ipv4 version to
not cast to inet_sock since it is unneeded.
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
UDP lib inuse checks will walk the entire hash bucket to check if the
portaddr is in use. In the case of reuseport we can stop searching when
we find a matching reuseport.
On a 16-core VM a test program that spawns 16 threads that each bind to
1024 sockets (one per 10ms) takes 1m45s. With this change it takes 11s.
Also add a cond_resched() when the port is not specified.
Signed-off-by: Eric Garver <e@erig.me>
Signed-off-by: David S. Miller <davem@davemloft.net>
This was entirely automated, using the script by Al:
PATT='^[[:blank:]]*#[[:blank:]]*include[[:blank:]]*<asm/uaccess.h>'
sed -i -e "s!$PATT!#include <linux/uaccess.h>!" \
$(git grep -l "$PATT"|grep -v ^include/linux/uaccess.h)
to do the replacement at the end of the merge window.
Requested-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
In flood situations, keeping sk_rmem_alloc at a high value
prevents producers from touching the socket.
It makes sense to lower sk_rmem_alloc only at the end
of udp_rmem_release() after the thread draining receive
queue in udp_recvmsg() finished the writes to sk_forward_alloc.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
If udp_recvmsg() constantly releases sk_rmem_alloc
for every read packet, it gives opportunity for
producers to immediately grab spinlocks and desperatly
try adding another packet, causing false sharing.
We can add a simple heuristic to give the signal
by batches of ~25 % of the queue capacity.
This patch considerably increases performance under
flood by about 50 %, since the thread draining the queue
is no longer slowed by false sharing.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
In UDP RX handler, we currently clear skb->dev before skb
is added to receive queue, because device pointer is no longer
available once we exit from RCU section.
Since this first cache line is always hot, lets reuse this space
to store skb->truesize and thus avoid a cache line miss at
udp_recvmsg()/udp_skb_destructor time while receive queue
spinlock is held.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Idea of busylocks is to let producers grab an extra spinlock
to relieve pressure on the receive_queue spinlock shared by consumer.
This behavior is requested only once socket receive queue is above
half occupancy.
Under flood, this means that only one producer can be in line
trying to acquire the receive_queue spinlock.
These busylock can be allocated on a per cpu manner, instead of a
per socket one (that would consume a cache line per socket)
This patch considerably improves UDP behavior under stress,
depending on number of NIC RX queues and/or RPS spread.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Under UDP flood, many softirq producers try to add packets to
UDP receive queue, and one user thread is burning one cpu trying
to dequeue packets as fast as possible.
Two parts of the per packet cost are :
- copying payload from kernel space to user space,
- freeing memory pieces associated with skb.
If socket is under pressure, softirq handler(s) can try to pull in
skb->head the payload of the packet if it fits.
Meaning the softirq handler(s) can free/reuse the page fragment
immediately, instead of letting udp_recvmsg() do this hundreds of usec
later, possibly from another node.
Additional gains :
- We reduce skb->truesize and thus can store more packets per SO_RCVBUF
- We avoid cache line misses at copyout() time and consume_skb() time,
and avoid one put_page() with potential alien freeing on NUMA hosts.
This comes at the cost of a copy, bounded to available tail room, which
is usually small. (We might have to fix GRO_MAX_HEAD which looks bigger
than necessary)
This patch gave me about 5 % increase in throughput in my tests.
skb_condense() helper could probably used in other contexts.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Before commit 850cbaddb5 ("udp: use it's own memory accounting
schema"), the udp protocol allowed sk_rmem_alloc to grow beyond
the rcvbuf by the whole current packet's truesize. After said commit
we allow sk_rmem_alloc to exceed the rcvbuf only if the receive queue
is empty. As reported by Jesper this cause a performance regression
for some (small) values of rcvbuf.
This commit is intended to fix the regression restoring the old
handling of the rcvbuf limit.
Reported-by: Jesper Dangaard Brouer <brouer@redhat.com>
Fixes: 850cbaddb5 ("udp: use it's own memory accounting schema")
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
udplite conflict is resolved by taking what 'net-next' did
which removed the backlog receive method assignment, since
it is no longer necessary.
Two entries were added to the non-priv ethtool operations
switch statement, one in 'net' and one in 'net-next, so
simple overlapping changes.
Signed-off-by: David S. Miller <davem@davemloft.net>
In commits 93821778de ("udp: Fix rcv socket locking") and
f7ad74fef3 ("net/ipv6/udp: UDP encapsulation: break backlog_rcv into
__udpv6_queue_rcv_skb") UDP backlog handlers were renamed, but UDPlite
was forgotten.
This leads to crashes if UDPlite header is pulled twice, which happens
starting from commit e6afc8ace6 ("udp: remove headers from UDP packets
before queueing")
Bug found by syzkaller team, thanks a lot guys !
Note that backlog use in UDP/UDPlite is scheduled to be removed starting
from linux-4.10, so this patch is only needed up to linux-4.9
Fixes: 93821778de ("udp: Fix rcv socket locking")
Fixes: f7ad74fef3 ("net/ipv6/udp: UDP encapsulation: break backlog_rcv into __udpv6_queue_rcv_skb")
Fixes: e6afc8ace6 ("udp: remove headers from UDP packets before queueing")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Andrey Konovalov <andreyknvl@google.com>
Cc: Benjamin LaHaise <bcrl@kvack.org>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
All conflicts were simple overlapping changes except perhaps
for the Thunder driver.
That driver has a change_mtu method explicitly for sending
a message to the hardware. If that fails it returns an
error.
Normally a driver doesn't need an ndo_change_mtu method becuase those
are usually just range changes, which are now handled generically.
But since this extra operation is needed in the Thunder driver, it has
to stay.
However, if the message send fails we have to restore the original
MTU before the change because the entire call chain expects that if
an error is thrown by ndo_change_mtu then the MTU did not change.
Therefore code is added to nicvf_change_mtu to remember the original
MTU, and to restore it upon nicvf_update_hw_max_frs() failue.
Signed-off-by: David S. Miller <davem@davemloft.net>
UDP_SKB_CB(skb)->partial_cov is located at offset 66 in skb,
requesting a cold cache line being read in cpu cache.
We can avoid this cache line miss for UDP sockets,
as partial_cov has a meaning only for UDPLite.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
UDP busy polling is restricted to connected UDP sockets.
This is because sk_busy_loop() only takes care of one NAPI context.
There are cases where it could be extended.
1) Some hosts receive traffic on a single NIC, with one RX queue.
2) Some applications use SO_REUSEPORT and associated BPF filter
to split the incoming traffic on one UDP socket per RX
queue/thread/cpu
3) Some UDP sockets are used to send/receive traffic for one flow, but
they do not bother with connect()
This patch records the napi_id of first received skb, giving more
reach to busy polling.
Tested:
lpaa23:~# echo 70 >/proc/sys/net/core/busy_read
lpaa24:~# echo 70 >/proc/sys/net/core/busy_read
lpaa23:~# for f in `seq 1 10`; do ./super_netperf 1 -H lpaa24 -t UDP_RR -l 5; done
Before patch :
27867 28870 37324 41060 41215
36764 36838 44455 41282 43843
After patch :
73920 73213 70147 74845 71697
68315 68028 75219 70082 73707
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Honor udptable parameter that is passed to __udp*_lib_mcast_deliver(),
otherwise udplite broadcast/multicast use the wrong table and it breaks.
Fixes: 2dc41cff75 ("udp: Use hash2 for long hash1 chains in __udp*_lib_mcast_deliver.")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The commit 850cbaddb5 ("udp: use it's own memory accounting schema")
assumes that the socket proto has memory accounting enabled,
but this is not the case for UDPLITE.
Fix it enabling memory accounting for UDPLITE and performing
fwd allocated memory reclaiming on socket shutdown.
UDP and UDPLITE share now the same memory accounting limits.
Also drop the backlog receive operation, since is no more needed.
Fixes: 850cbaddb5 ("udp: use it's own memory accounting schema")
Reported-by: Andrei Vagin <avagin@gmail.com>
Suggested-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Pablo Neira Ayuso says:
====================
Netfilter updates for net-next
The following patchset contains a second batch of Netfilter updates for
your net-next tree. This includes a rework of the core hook
infrastructure that improves Netfilter performance by ~15% according to
synthetic benchmarks. Then, a large batch with ipset updates, including
a new hash:ipmac set type, via Jozsef Kadlecsik. This also includes a
couple of assorted updates.
Regarding the core hook infrastructure rework to improve performance,
using this simple drop-all packets ruleset from ingress:
nft add table netdev x
nft add chain netdev x y { type filter hook ingress device eth0 priority 0\; }
nft add rule netdev x y drop
And generating traffic through Jesper Brouer's
samples/pktgen/pktgen_bench_xmit_mode_netif_receive.sh script using -i
option. perf report shows nf_tables calls in its top 10:
17.30% kpktgend_0 [nf_tables] [k] nft_do_chain
15.75% kpktgend_0 [kernel.vmlinux] [k] __netif_receive_skb_core
10.39% kpktgend_0 [nf_tables_netdev] [k] nft_do_chain_netdev
I'm measuring here an improvement of ~15% in performance with this
patchset, so we got +2.5Mpps more. I have used my old laptop Intel(R)
Core(TM) i5-3320M CPU @ 2.60GHz 4-cores.
This rework contains more specifically, in strict order, these patches:
1) Remove compile-time debugging from core.
2) Remove obsolete comments that predate the rcu era. These days it is
well known that a Netfilter hook always runs under rcu_read_lock().
3) Remove threshold handling, this is only used by br_netfilter too.
We already have specific code to handle this from br_netfilter,
so remove this code from the core path.
4) Deprecate NF_STOP, as this is only used by br_netfilter.
5) Place nf_state_hook pointer into xt_action_param structure, so
this structure fits into one single cacheline according to pahole.
This also implicit affects nftables since it also relies on the
xt_action_param structure.
6) Move state->hook_entries into nf_queue entry. The hook_entries
pointer is only required by nf_queue(), so we can store this in the
queue entry instead.
7) use switch() statement to handle verdict cases.
8) Remove hook_entries field from nf_hook_state structure, this is only
required by nf_queue, so store it in nf_queue_entry structure.
9) Merge nf_iterate() into nf_hook_slow() that results in a much more
simple and readable function.
10) Handle NF_REPEAT away from the core, so far the only client is
nf_conntrack_in() and we can restart the packet processing using a
simple goto to jump back there when the TCP requires it.
This update required a second pass to fix fallout, fix from
Arnd Bergmann.
11) Set random seed from nft_hash when no seed is specified from
userspace.
12) Simplify nf_tables expression registration, in a much smarter way
to save lots of boiler plate code, by Liping Zhang.
13) Simplify layer 4 protocol conntrack tracker registration, from
Davide Caratti.
14) Missing CONFIG_NF_SOCKET_IPV4 dependency for udp4_lib_lookup, due
to recent generalization of the socket infrastructure, from Arnd
Bergmann.
15) Then, the ipset batch from Jozsef, he describes it as it follows:
* Cleanup: Remove extra whitespaces in ip_set.h
* Cleanup: Mark some of the helpers arguments as const in ip_set.h
* Cleanup: Group counter helper functions together in ip_set.h
* struct ip_set_skbinfo is introduced instead of open coded fields
in skbinfo get/init helper funcions.
* Use kmalloc() in comment extension helper instead of kzalloc()
because it is unnecessary to zero out the area just before
explicit initialization.
* Cleanup: Split extensions into separate files.
* Cleanup: Separate memsize calculation code into dedicated function.
* Cleanup: group ip_set_put_extensions() and ip_set_get_extensions()
together.
* Add element count to hash headers by Eric B Munson.
* Add element count to all set types header for uniform output
across all set types.
* Count non-static extension memory into memsize calculation for
userspace.
* Cleanup: Remove redundant mtype_expire() arguments, because
they can be get from other parameters.
* Cleanup: Simplify mtype_expire() for hash types by removing
one level of intendation.
* Make NLEN compile time constant for hash types.
* Make sure element data size is a multiple of u32 for the hash set
types.
* Optimize hash creation routine, exit as early as possible.
* Make struct htype per ipset family so nets array becomes fixed size
and thus simplifies the struct htype allocation.
* Collapse same condition body into a single one.
* Fix reported memory size for hash:* types, base hash bucket structure
was not taken into account.
* hash:ipmac type support added to ipset by Tomasz Chilinski.
* Use setup_timer() and mod_timer() instead of init_timer()
by Muhammad Falak R Wani, individually for the set type families.
16) Remove useless connlabel field in struct netns_ct, patch from
Florian Westphal.
17) xt_find_table_lock() doesn't return ERR_PTR() anymore, so simplify
{ip,ip6,arp}tables code that uses this.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Since commit ca065d0cf8 ("udp: no longer use SLAB_DESTROY_BY_RCU")
the udp6_lib_lookup and udp4_lib_lookup functions are only
provided when it is actually possible to call them.
However, moving the callers now caused a link error:
net/built-in.o: In function `nf_sk_lookup_slow_v6':
(.text+0x131a39): undefined reference to `udp6_lib_lookup'
net/ipv4/netfilter/nf_socket_ipv4.o: In function `nf_sk_lookup_slow_v4':
nf_socket_ipv4.c:(.text.nf_sk_lookup_slow_v4+0x114): undefined reference to `udp4_lib_lookup'
This extends the #ifdef so we also provide the functions when
CONFIG_NF_SOCKET_IPV4 or CONFIG_NF_SOCKET_IPV6, respectively
are set.
Fixes: 8db4c5be88 ("netfilter: move socket lookup infrastructure to nf_socket_ipv{4,6}.c")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
A new argument is added to __skb_recv_datagram to provide
an explicit skb destructor, invoked under the receive queue
lock.
The UDP protocol uses such argument to perform memory
reclaiming on dequeue, so that the UDP protocol does not
set anymore skb->desctructor.
Instead explicit memory reclaiming is performed at close() time and
when skbs are removed from the receive queue.
The in kernel UDP protocol users now need to call a
skb_recv_udp() variant instead of skb_recv_datagram() to
properly perform memory accounting on dequeue.
Overall, this allows acquiring only once the receive queue
lock on dequeue.
Tested using pktgen with random src port, 64 bytes packet,
wire-speed on a 10G link as sender and udp_sink as the receiver,
using an l4 tuple rxhash to stress the contention, and one or more
udp_sink instances with reuseport.
nr sinks vanilla patched
1 440 560
3 2150 2300
6 3650 3800
9 4450 4600
12 6250 6450
v1 -> v2:
- do rmem and allocated memory scheduling under the receive lock
- do bulk scheduling in first_packet_length() and in udp_destruct_sock()
- avoid the typdef for the dequeue callback
Suggested-by: Eric Dumazet <edumazet@google.com>
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>
So that we can use it even after orphaining the skbuff.
Suggested-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
- Use the UID in routing lookups made by protocol connect() and
sendmsg() functions.
- Make sure that routing lookups triggered by incoming packets
(e.g., Path MTU discovery) take the UID of the socket into
account.
- For packets not associated with a userspace socket, (e.g., ping
replies) use UID 0 inside the user namespace corresponding to
the network namespace the socket belongs to. This allows
all namespaces to apply routing and iptables rules to
kernel-originated traffic in that namespaces by matching UID 0.
This is better than using the UID of the kernel socket that is
sending the traffic, because the UID of kernel sockets created
at namespace creation time (e.g., the per-processor ICMP and
TCP sockets) is the UID of the user that created the socket,
which might not be mapped in the namespace.
Tested: compiles allnoconfig, allyesconfig, allmodconfig
Tested: https://android-review.googlesource.com/253302
Signed-off-by: Lorenzo Colitti <lorenzo@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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>
First bug was added in commit ad6f939ab1 ("ip: Add offset parameter to
ip_cmsg_recv") : Tom missed that ipv4 udp messages could be received on
AF_INET6 socket. ip_cmsg_recv(msg, skb) should have been replaced by
ip_cmsg_recv_offset(msg, skb, sizeof(struct udphdr));
Then commit e6afc8ace6 ("udp: remove headers from UDP packets before
queueing") forgot to adjust the offsets now UDP headers are pulled
before skb are put in receive queue.
Fixes: ad6f939ab1 ("ip: Add offset parameter to ip_cmsg_recv")
Fixes: e6afc8ace6 ("udp: remove headers from UDP packets before queueing")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Sam Kumar <samanthakumar@google.com>
Cc: Willem de Bruijn <willemb@google.com>
Tested-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Completely avoid default sock memory accounting and replace it
with udp-specific accounting.
Since the new memory accounting model encapsulates completely
the required locking, remove the socket lock on both enqueue and
dequeue, and avoid using the backlog on enqueue.
Be sure to clean-up rx queue memory on socket destruction, using
udp its own sk_destruct.
Tested using pktgen with random src port, 64 bytes packet,
wire-speed on a 10G link as sender and udp_sink as the receiver,
using an l4 tuple rxhash to stress the contention, and one or more
udp_sink instances with reuseport.
nr readers Kpps (vanilla) Kpps (patched)
1 170 440
3 1250 2150
6 3000 3650
9 4200 4450
12 5700 6250
v4 -> v5:
- avoid unneeded test in first_packet_length
v3 -> v4:
- remove useless sk_rcvqueues_full() call
v2 -> v3:
- do not set the now unsed backlog_rcv callback
v1 -> v2:
- add memory pressure support
- fixed dropwatch accounting for ipv6
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>
Avoid using the generic helpers.
Use the receive queue spin lock to protect the memory
accounting operation, both on enqueue and on dequeue.
On dequeue perform partial memory reclaiming, trying to
leave a quantum of forward allocated memory.
On enqueue use a custom helper, to allow some optimizations:
- use a plain spin_lock() variant instead of the slightly
costly spin_lock_irqsave(),
- avoid dst_force check, since the calling code has already
dropped the skb dst
- avoid orphaning the skb, since skb_steal_sock() already did
the work for us
The above needs custom memory reclaiming on shutdown, provided
by the udp_destruct_sock().
v5 -> v6:
- don't orphan the skb on enqueue
v4 -> v5:
- replace the mem_lock with the receive queue spin lock
- ensure that the bh is always allowed to enqueue at least
a skb, even if sk_rcvbuf is exceeded
v3 -> v4:
- reworked memory accunting, simplifying the schema
- provide an helper for both memory scheduling and enqueuing
v1 -> v2:
- use a udp specific destrctor to perform memory reclaiming
- remove a couple of helpers, unneeded after the above cleanup
- do not reclaim memory on dequeue if not under memory
pressure
- reworked the fwd accounting schema to avoid potential
integer overflow
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>
Baozeng Ding reported KASAN traces showing uses after free in
udp_lib_get_port() and other related UDP functions.
A CONFIG_DEBUG_PAGEALLOC=y kernel would eventually crash.
I could write a reproducer with two threads doing :
static int sock_fd;
static void *thr1(void *arg)
{
for (;;) {
connect(sock_fd, (const struct sockaddr *)arg,
sizeof(struct sockaddr_in));
}
}
static void *thr2(void *arg)
{
struct sockaddr_in unspec;
for (;;) {
memset(&unspec, 0, sizeof(unspec));
connect(sock_fd, (const struct sockaddr *)&unspec,
sizeof(unspec));
}
}
Problem is that udp_disconnect() could run without holding socket lock,
and this was causing list corruptions.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Baozeng Ding <sploving1@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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>
This implements SOCK_DESTROY for UDP sockets similar to what was done
for TCP with commit c1e64e298b ("net: diag: Support destroying TCP
sockets.") A process with a UDP socket targeted for destroy is awakened
and recvmsg fails with ECONNABORTED.
Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
After commit ca065d0cf8 ("udp: no longer use SLAB_DESTROY_BY_RCU")
we do not need this special allocation mode anymore, even if it is
harmless.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Laura tracked poll() [and friends] regression caused by commit
e6afc8ace6 ("udp: remove headers from UDP packets before queueing")
udp_poll() needs to know if there is a valid packet in receive queue,
even if its payload length is 0.
Change first_packet_length() to return an signed int, and use -1
as the indication of an empty queue.
Fixes: e6afc8ace6 ("udp: remove headers from UDP packets before queueing")
Reported-by: Laura Abbott <labbott@redhat.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Tested-by: Laura Abbott <labbott@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Include ipv4_rcv_saddr_equal() definition to avoid this sparse error :
net/ipv4/udp.c:362:5: warning: symbol 'ipv4_rcv_saddr_equal' was not
declared. Should it be static?
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
After a612769774 ("udp: prevent bugcheck if filter truncates packet
too much"), there followed various other fixes for similar cases such
as f4979fcea7 ("rose: limit sk_filter trim to payload").
Latter introduced a new helper sk_filter_trim_cap(), where we can pass
the trim limit directly to the socket filter handling. Make use of it
here as well with sizeof(struct udphdr) as lower cap limit and drop the
extra skb->len test in UDP's input path.
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Cc: Willem de Bruijn <willemb@google.com>
Acked-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
If socket filter truncates an udp packet below the length of UDP header
in udpv6_queue_rcv_skb() or udp_queue_rcv_skb(), it will trigger a
BUG_ON in skb_pull_rcsum(). This BUG_ON (and therefore a system crash if
kernel is configured that way) can be easily enforced by an unprivileged
user which was reported as CVE-2016-6162. For a reproducer, see
http://seclists.org/oss-sec/2016/q3/8
Fixes: e6afc8ace6 ("udp: remove headers from UDP packets before queueing")
Reported-by: Marco Grassi <marco.gra@gmail.com>
Signed-off-by: Michal Kubecek <mkubecek@suse.cz>
Acked-by: Eric Dumazet <edumazet@google.com>
Acked-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
There is a corner case in which udp packets belonging to a same
flow are hashed to different socket when hslot->count changes from 10
to 11:
1) When hslot->count <= 10, __udp_lib_lookup() searches udp_table->hash,
and always passes 'daddr' to udp_ehashfn().
2) When hslot->count > 10, __udp_lib_lookup() searches udp_table->hash2,
but may pass 'INADDR_ANY' to udp_ehashfn() if the sockets are bound to
INADDR_ANY instead of some specific addr.
That means when hslot->count changes from 10 to 11, the hash calculated by
udp_ehashfn() is also changed, and the udp packets belonging to a same
flow will be hashed to different socket.
This is easily reproduced:
1) Create 10 udp sockets and bind all of them to 0.0.0.0:40000.
2) From the same host send udp packets to 127.0.0.1:40000, record the
socket index which receives the packets.
3) Create 1 more udp socket and bind it to 0.0.0.0:44096. The number 44096
is 40000 + UDP_HASH_SIZE(4096), this makes the new socket put into the
same hslot as the aformentioned 10 sockets, and makes the hslot->count
change from 10 to 11.
4) From the same host send udp packets to 127.0.0.1:40000, and the socket
index which receives the packets will be different from the one received
in step 2.
This should not happen as the socket bound to 0.0.0.0:44096 should not
change the behavior of the sockets bound to 0.0.0.0:40000.
It's the same case for IPv6, and this patch also fixes that.
Signed-off-by: Su, Xuemin <suxm@chinanetcenter.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Reported-by: Cong Wang <xiyou.wangcong@gmail.com>
Cc: Cong Wang <xiyou.wangcong@gmail.com>
Cc: Tom Herbert <tom@herbertland.com>
Fixes: 4068579e1e ("net: Implmement RFC 6936 (zero RX csums for UDP/IPv6")
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Paul Moore tracked a regression caused by a recent commit, which
mistakenly assumed that sk_filter() could be avoided if socket
had no current BPF filter.
The intent was to avoid udp_lib_checksum_complete() overhead.
But sk_filter() also checks skb_pfmemalloc() and
security_sock_rcv_skb(), so better call it.
Fixes: e6afc8ace6 ("udp: remove headers from UDP packets before queueing")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Paul Moore <paul@paul-moore.com>
Tested-by: Paul Moore <paul@paul-moore.com>
Tested-by: Stephen Smalley <sds@tycho.nsa.gov>
Cc: samanthakumar <samanthakumar@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
In case we find a socket with encapsulation enabled we should call
the encap_recv function even if just a udp header without payload is
available. The callbacks are responsible for correctly verifying and
dropping the packets.
Also, in case the header validation fails for geneve and vxlan we
shouldn't put the skb back into the socket queue, no one will pick
them up there. Instead we can simply discard them in the respective
encap_recv functions.
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
While testing an OpenStack configuration using VXLANs I saw the following
call trace:
RIP: 0010:[<ffffffff815fad49>] udp4_lib_lookup_skb+0x49/0x80
RSP: 0018:ffff88103867bc50 EFLAGS: 00010286
RAX: ffff88103269bf00 RBX: ffff88103269bf00 RCX: 00000000ffffffff
RDX: 0000000000004300 RSI: 0000000000000000 RDI: ffff880f2932e780
RBP: ffff88103867bc60 R08: 0000000000000000 R09: 000000009001a8c0
R10: 0000000000004400 R11: ffffffff81333a58 R12: ffff880f2932e794
R13: 0000000000000014 R14: 0000000000000014 R15: ffffe8efbfd89ca0
FS: 0000000000000000(0000) GS:ffff88103fd80000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000488 CR3: 0000000001c06000 CR4: 00000000001426e0
Stack:
ffffffff81576515 ffffffff815733c0 ffff88103867bc98 ffffffff815fcc17
ffff88103269bf00 ffffe8efbfd89ca0 0000000000000014 0000000000000080
ffffe8efbfd89ca0 ffff88103867bcc8 ffffffff815fcf8b ffff880f2932e794
Call Trace:
[<ffffffff81576515>] ? skb_checksum+0x35/0x50
[<ffffffff815733c0>] ? skb_push+0x40/0x40
[<ffffffff815fcc17>] udp_gro_receive+0x57/0x130
[<ffffffff815fcf8b>] udp4_gro_receive+0x10b/0x2c0
[<ffffffff81605863>] inet_gro_receive+0x1d3/0x270
[<ffffffff81589e59>] dev_gro_receive+0x269/0x3b0
[<ffffffff8158a1b8>] napi_gro_receive+0x38/0x120
[<ffffffffa0871297>] gro_cell_poll+0x57/0x80 [vxlan]
[<ffffffff815899d0>] net_rx_action+0x160/0x380
[<ffffffff816965c7>] __do_softirq+0xd7/0x2c5
[<ffffffff8107d969>] run_ksoftirqd+0x29/0x50
[<ffffffff8109a50f>] smpboot_thread_fn+0x10f/0x160
[<ffffffff8109a400>] ? sort_range+0x30/0x30
[<ffffffff81096da8>] kthread+0xd8/0xf0
[<ffffffff81693c82>] ret_from_fork+0x22/0x40
[<ffffffff81096cd0>] ? kthread_park+0x60/0x60
The following trace is seen when receiving a DHCP request over a flow-based
VXLAN tunnel. I believe this is caused by the metadata dst having a NULL
dev value and as a result dev_net(dev) is causing a NULL pointer dereference.
To resolve this I am replacing the check for skb_dst(skb)->dev with just
skb->dev. This makes sense as the callers of this function are usually in
the receive path and as such skb->dev should always be populated. In
addition other functions in the area where these are called are already
using dev_net(skb->dev) to determine the namespace the UDP packet belongs
in.
Fixes: 63058308cd ("udp: Add udp6_lib_lookup_skb and udp4_lib_lookup_skb")
Signed-off-by: Alexander Duyck <aduyck@mirantis.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
UDP uses the generic socket backlog code, and this will soon
be changed to not disable BH when protocol is called back.
We need to use appropriate SNMP accessors.
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>
Rename UDP_INC_STATS_BH() to __UDP_INC_STATS(),
and UDP6_INC_STATS_BH() to __UDP6_INC_STATS()
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Rename ICMP_INC_STATS_BH() to __ICMP_INC_STATS()
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
In the old days (before linux-3.0), SNMP counters were duplicated,
one for user context, and one for BH context.
After commit 8f0ea0fe3a ("snmp: reduce percpu needs by 50%")
we have a single copy, and what really matters is preemption being
enabled or disabled, since we use this_cpu_inc() or __this_cpu_inc()
respectively.
We therefore kill SNMP_INC_STATS_USER(), SNMP_ADD_STATS_USER(),
NET_INC_STATS_USER(), NET_ADD_STATS_USER(), SCTP_INC_STATS_USER(),
SNMP_INC_STATS64_USER(), SNMP_ADD_STATS64_USER(), TCP_ADD_STATS_USER(),
UDP_INC_STATS_USER(), UDP6_INC_STATS_USER(), and XFRM_INC_STATS_USER()
Following patches will rename __BH helpers to make clear their
usage is not tied to BH being disabled.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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>
Paolo Abeni