idev->cnf.forwarding and net->ipv6.devconf_all->forwarding
might be read locklessly, add appropriate READ_ONCE()
and WRITE_ONCE() annotations.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
In bhash2, IPv4/IPv6 addresses are saved in two union members,
which complicate address checks in inet_bind2_bucket_addr_match()
and inet_bind2_bucket_match_addr_any() considering uninitialised
memory and v4-mapped-v6 conflicts.
Let's simplify that by saving IPv4 address as v4-mapped-v6 address
and defining tb2.rcv_saddr as tb2.v6_rcv_saddr.s6_addr32[3].
Then, we can compare v6 address as is, and after checking v4-mapped-v6,
we can compare v4 address easily. Also, we can remove tb2->family.
Note these functions will be further refactored in the next patch.
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
At the moment ip6_dst_lookup_tunnel() is used only by bareudp.
Ideally, other UDP tunnel implementations should use it, but to do so
the function needs to accept new parameters that are specific for UDP
tunnels, such as the ports.
Prepare for these changes by renaming the function to
udp_tunnel6_dst_lookup() and move it to file
net/ipv6/ip6_udp_tunnel.c.
This is similar to what already done for IPv4 in commit bf3fcbf7e7
("ipv4: rename and move ip_route_output_tunnel()").
Suggested-by: Guillaume Nault <gnault@redhat.com>
Signed-off-by: Beniamino Galvani <b.galvani@gmail.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Move np->autoflowlabel and np->autoflowlabel_set in inet->inet_flags,
to fix data-races.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
This fixes data-races around np->mcast_hops,
and make IPV6_MULTICAST_HOPS lockless.
Note that np->mcast_hops is never negative,
thus can fit an u8 field instead of s16.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Some np->hop_limit accesses are racy, when socket lock is not held.
Add missing annotations and switch to full lockless implementation.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Andrei Vagin reported bind() regression with strace logs.
If we bind() a TCPv6 socket to ::FFFF:0.0.0.0 and then bind() a TCPv4
socket to 127.0.0.1, the 2nd bind() should fail but now succeeds.
from socket import *
s1 = socket(AF_INET6, SOCK_STREAM)
s1.bind(('::ffff:0.0.0.0', 0))
s2 = socket(AF_INET, SOCK_STREAM)
s2.bind(('127.0.0.1', s1.getsockname()[1]))
During the 2nd bind(), if tb->family is AF_INET6 and sk->sk_family is
AF_INET in inet_bind2_bucket_match_addr_any(), we still need to check
if tb has the v4-mapped-v6 wildcard address.
The example above does not work after commit 5456262d2b ("net: Fix
incorrect address comparison when searching for a bind2 bucket"), but
the blamed change is not the commit.
Before the commit, the leading zeros of ::FFFF:0.0.0.0 were treated
as 0.0.0.0, and the sequence above worked by chance. Technically, this
case has been broken since bhash2 was introduced.
Note that if we bind() two sockets to 127.0.0.1 and then ::FFFF:0.0.0.0,
the 2nd bind() fails properly because we fall back to using bhash to
detect conflicts for the v4-mapped-v6 address.
Fixes: 28044fc1d4 ("net: Add a bhash2 table hashed by port and address")
Reported-by: Andrei Vagin <avagin@google.com>
Closes: https://lore.kernel.org/netdev/ZPuYBOFC8zsK6r9T@google.com/
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Pull sysctl updates from Luis Chamberlain:
"Long ago we set out to remove the kitchen sink on kernel/sysctl.c
arrays and placings sysctls to their own sybsystem or file to help
avoid merge conflicts. Matthew Wilcox pointed out though that if we're
going to do that we might as well also *save* space while at it and
try to remove the extra last sysctl entry added at the end of each
array, a sentintel, instead of bloating the kernel by adding a new
sentinel with each array moved.
Doing that was not so trivial, and has required slowing down the moves
of kernel/sysctl.c arrays and measuring the impact on size by each new
move.
The complex part of the effort to help reduce the size of each sysctl
is being done by the patient work of el señor Don Joel Granados. A lot
of this is truly painful code refactoring and testing and then trying
to measure the savings of each move and removing the sentinels.
Although Joel already has code which does most of this work,
experience with sysctl moves in the past shows is we need to be
careful due to the slew of odd build failures that are possible due to
the amount of random Kconfig options sysctls use.
To that end Joel's work is split by first addressing the major
housekeeping needed to remove the sentinels, which is part of this
merge request. The rest of the work to actually remove the sentinels
will be done later in future kernel releases.
The preliminary math is showing this will all help reduce the overall
build time size of the kernel and run time memory consumed by the
kernel by about ~64 bytes per array where we are able to remove each
sentinel in the future. That also means there is no more bloating the
kernel with the extra ~64 bytes per array moved as no new sentinels
are created"
* tag 'sysctl-6.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux:
sysctl: Use ctl_table_size as stopping criteria for list macro
sysctl: SIZE_MAX->ARRAY_SIZE in register_net_sysctl
vrf: Update to register_net_sysctl_sz
networking: Update to register_net_sysctl_sz
netfilter: Update to register_net_sysctl_sz
ax.25: Update to register_net_sysctl_sz
sysctl: Add size to register_net_sysctl function
sysctl: Add size arg to __register_sysctl_init
sysctl: Add size to register_sysctl
sysctl: Add a size arg to __register_sysctl_table
sysctl: Add size argument to init_header
sysctl: Add ctl_table_size to ctl_table_header
sysctl: Use ctl_table_header in list_for_each_table_entry
sysctl: Prefer ctl_table_header in proc_sysctl
IP_TRANSPARENT socket option can now be set/read
without locking the socket.
v2: removed unused issk variable in mptcp_setsockopt_sol_ip_set_transparent()
v4: rebased after commit 3f326a821b ("mptcp: change the mpc check helper to return a sk")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Paolo Abeni <pabeni@redhat.com>
Acked-by: Soheil Hassas Yeganeh <soheil@google.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Move from register_net_sysctl to register_net_sysctl_sz for all the
networking related files. Do this while making sure to mirror the NULL
assignments with a table_size of zero for the unprivileged users.
We need to move to the new function in preparation for when we change
SIZE_MAX to ARRAY_SIZE() in the register_net_sysctl macro. Failing to do
so would erroneously allow ARRAY_SIZE() to be called on a pointer. We
hold off the SIZE_MAX to ARRAY_SIZE change until we have migrated all
the relevant net sysctl registering functions to register_net_sysctl_sz
in subsequent commits.
An additional size function was added to the following files in order to
calculate the size of an array that is defined in another file:
include/net/ipv6.h
net/ipv6/icmp.c
net/ipv6/route.c
net/ipv6/sysctl_net_ipv6.c
Signed-off-by: Joel Granados <j.granados@samsung.com>
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
The mptcp protocol maintains an additional socket just to easily
invoke a few stream operations on the first subflow. One of
them is bind().
Factor out the helpers operating directly on the struct sock, to
allow get rid of the above dependency in the next patch without
duplicating the existing code.
No functional changes intended.
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Acked-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
For both IPv4 and IPv6 incoming TCP connections are tracked in a hash
table with a hash over the source & destination addresses and ports.
However, the IPv6 hash is insufficient and can lead to a high rate of
collisions.
The IPv6 hash used an XOR to fit everything into the 96 bits for the
fast jenkins hash, meaning it is possible for an external entity to
ensure the hash collides, thus falling back to a linear search in the
bucket, which is slow.
We take the approach of hash the full length of IPv6 address in
__ipv6_addr_jhash() so that all users can benefit from a more secure
version.
While this may look like it adds overhead, the reality of modern CPUs
means that this is unmeasurable in real world scenarios.
In simulating with llvm-mca, the increase in cycles for the hashing
code was ~16 cycles on Skylake (from a base of ~155), and an extra ~9
on Nehalem (base of ~173).
In commit dd6d2910c5 ("netfilter: conntrack: switch to siphash")
netfilter switched from a jenkins hash to a siphash, but even the faster
hsiphash is a more significant overhead (~20-30%) in some preliminary
testing. So, in this patch, we keep to the more conservative approach to
ensure we don't add much overhead per SYN.
In testing, this results in a consistently even spread across the
connection buckets. In both testing and real-world scenarios, we have
not found any measurable performance impact.
Fixes: 08dcdbf6a7 ("ipv6: use a stronger hash for tcp")
Signed-off-by: Stewart Smith <trawets@amazon.com>
Signed-off-by: Samuel Mendoza-Jonas <samjonas@amazon.com>
Suggested-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://lore.kernel.org/r/20230721222410.17914-1-kuniyu@amazon.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Accurately reports what happened in icmpv6_notify() when handling
a packet.
This makes use of the new IPV6_BAD_EXTHDR drop reason.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
IPv6/TCP and GRO stacks can build big TCP packets with an added
temporary Hop By Hop header.
Is GSO is not involved, then the temporary header needs to be removed in
the driver. This patch provides a generic helper for drivers that need
to modify their headers in place.
Tested:
Compiled and ran with ethtool -K eth1 tso off
Could send Big TCP packets
Signed-off-by: Coco Li <lixiaoyan@google.com>
Link: https://lore.kernel.org/r/20221210041646.3587757-1-lixiaoyan@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
kernel test robot reported warnings when build bonding module with
make W=1 O=build_dir ARCH=x86_64 SHELL=/bin/bash drivers/net/bonding/:
from ../drivers/net/bonding/bond_main.c:35:
In function ‘fortify_memcpy_chk’,
inlined from ‘iph_to_flow_copy_v4addrs’ at ../include/net/ip.h:566:2,
inlined from ‘bond_flow_ip’ at ../drivers/net/bonding/bond_main.c:3984:3:
../include/linux/fortify-string.h:413:25: warning: call to ‘__read_overflow2_field’ declared with attribute warning: detected read beyond size of f
ield (2nd parameter); maybe use struct_group()? [-Wattribute-warning]
413 | __read_overflow2_field(q_size_field, size);
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
In function ‘fortify_memcpy_chk’,
inlined from ‘iph_to_flow_copy_v6addrs’ at ../include/net/ipv6.h:900:2,
inlined from ‘bond_flow_ip’ at ../drivers/net/bonding/bond_main.c:3994:3:
../include/linux/fortify-string.h:413:25: warning: call to ‘__read_overflow2_field’ declared with attribute warning: detected read beyond size of f
ield (2nd parameter); maybe use struct_group()? [-Wattribute-warning]
413 | __read_overflow2_field(q_size_field, size);
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
This is because we try to copy the whole ip/ip6 address to the flow_key,
while we only point the to ip/ip6 saddr. Note that since these are UAPI
headers, __struct_group() is used to avoid the compiler warnings.
Reported-by: kernel test robot <lkp@intel.com>
Fixes: c3f8324188 ("net: Add full IPv6 addresses to flow_keys")
Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>
Link: https://lore.kernel.org/r/20221115142400.1204786-1-liuhangbin@gmail.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Originally, inet6_sk(sk)->XXX were changed under lock_sock(), so we were
able to clean them up by calling inet6_destroy_sock() during the IPv6 ->
IPv4 conversion by IPV6_ADDRFORM. However, commit 03485f2adc ("udpv6:
Add lockless sendmsg() support") added a lockless memory allocation path,
which could cause a memory leak:
setsockopt(IPV6_ADDRFORM) sendmsg()
+-----------------------+ +-------+
- do_ipv6_setsockopt(sk, ...) - udpv6_sendmsg(sk, ...)
- sockopt_lock_sock(sk) ^._ called via udpv6_prot
- lock_sock(sk) before WRITE_ONCE()
- WRITE_ONCE(sk->sk_prot, &tcp_prot)
- inet6_destroy_sock() - if (!corkreq)
- sockopt_release_sock(sk) - ip6_make_skb(sk, ...)
- release_sock(sk) ^._ lockless fast path for
the non-corking case
- __ip6_append_data(sk, ...)
- ipv6_local_rxpmtu(sk, ...)
- xchg(&np->rxpmtu, skb)
^._ rxpmtu is never freed.
- goto out_no_dst;
- lock_sock(sk)
For now, rxpmtu is only the case, but not to miss the future change
and a similar bug fixed in commit e27326009a ("net: ping6: Fix
memleak in ipv6_renew_options()."), let's set a new function to IPv6
sk->sk_destruct() and call inet6_cleanup_sock() there. Since the
conversion does not change sk->sk_destruct(), we can guarantee that
we can clean up IPv6 resources finally.
We can now remove all inet6_destroy_sock() calls from IPv6 protocol
specific ->destroy() functions, but such changes are invasive to
backport. So they can be posted as a follow-up later for net-next.
Fixes: 03485f2adc ("udpv6: Add lockless sendmsg() support")
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Commit 4b340ae20d ("IPv6: Complete IPV6_DONTFRAG support") forgot
to add a change to free inet6_sk(sk)->rxpmtu while converting an IPv6
socket into IPv4 with IPV6_ADDRFORM. After conversion, sk_prot is
changed to udp_prot and ->destroy() never cleans it up, resulting in
a memory leak.
This is due to the discrepancy between inet6_destroy_sock() and
IPV6_ADDRFORM, so let's call inet6_destroy_sock() from IPV6_ADDRFORM
to remove the difference.
However, this is not enough for now because rxpmtu can be changed
without lock_sock() after commit 03485f2adc ("udpv6: Add lockless
sendmsg() support"). We will fix this case in the following patch.
Note we will rename inet6_destroy_sock() to inet6_cleanup_sock() and
remove unnecessary inet6_destroy_sock() calls in sk_prot->destroy()
in the future.
Fixes: 4b340ae20d ("IPv6: Complete IPV6_DONTFRAG support")
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
