tm->tcpm_lock can be read or written locklessly.
Add needed READ_ONCE()/WRITE_ONCE() to document this.
Fixes: 51c5d0c4b1 ("tcp: Maintain dynamic metrics in local cache.")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Link: https://lore.kernel.org/r/20230802131500.1478140-4-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
tm->tcpm_stamp can be read or written locklessly.
Add needed READ_ONCE()/WRITE_ONCE() to document this.
Also constify tcpm_check_stamp() dst argument.
Fixes: 51c5d0c4b1 ("tcp: Maintain dynamic metrics in local cache.")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Link: https://lore.kernel.org/r/20230802131500.1478140-3-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Because v4 and v6 families use separate inetpeer trees (respectively
net->ipv4.peers and net->ipv6.peers), inetpeer_addr_cmp(a, b) assumes
a & b share the same family.
tcp_metrics use a common hash table, where entries can have different
families.
We must therefore make sure to not call inetpeer_addr_cmp()
if the families do not match.
Fixes: d39d14ffa2 ("net: Add helper function to compare inetpeer addresses")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Link: https://lore.kernel.org/r/20230802131500.1478140-2-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
__ip_append_data() can get into an infinite loop when asked to splice into
a partially-built UDP message that has more than the frag-limit data and up
to the MTU limit. Something like:
pipe(pfd);
sfd = socket(AF_INET, SOCK_DGRAM, 0);
connect(sfd, ...);
send(sfd, buffer, 8161, MSG_CONFIRM|MSG_MORE);
write(pfd[1], buffer, 8);
splice(pfd[0], 0, sfd, 0, 0x4ffe0ul, 0);
where the amount of data given to send() is dependent on the MTU size (in
this instance an interface with an MTU of 8192).
The problem is that the calculation of the amount to copy in
__ip_append_data() goes negative in two places, and, in the second place,
this gets subtracted from the length remaining, thereby increasing it.
This happens when pagedlen > 0 (which happens for MSG_ZEROCOPY and
MSG_SPLICE_PAGES), because the terms in:
copy = datalen - transhdrlen - fraggap - pagedlen;
then mostly cancel when pagedlen is substituted for, leaving just -fraggap.
This causes:
length -= copy + transhdrlen;
to increase the length to more than the amount of data in msg->msg_iter,
which causes skb_splice_from_iter() to be unable to fill the request and it
returns less than 'copied' - which means that length never gets to 0 and we
never exit the loop.
Fix this by:
(1) Insert a note about the dodgy calculation of 'copy'.
(2) If MSG_SPLICE_PAGES, clear copy if it is negative from the above
equation, so that 'offset' isn't regressed and 'length' isn't
increased, which will mean that length and thus copy should match the
amount left in the iterator.
(3) When handling MSG_SPLICE_PAGES, give a warning and return -EIO if
we're asked to splice more than is in the iterator. It might be
better to not give the warning or even just give a 'short' write.
[!] Note that this ought to also affect MSG_ZEROCOPY, but MSG_ZEROCOPY
avoids the problem by simply assuming that everything asked for got copied,
not just the amount that was in the iterator. This is a potential bug for
the future.
Fixes: 7ac7c98785 ("udp: Convert udp_sendpage() to use MSG_SPLICE_PAGES")
Reported-by: syzbot+f527b971b4bdc8e79f9e@syzkaller.appspotmail.com
Link: https://lore.kernel.org/r/000000000000881d0606004541d1@google.com/
Signed-off-by: David Howells <dhowells@redhat.com>
cc: David Ahern <dsahern@kernel.org>
cc: Jens Axboe <axboe@kernel.dk>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Link: https://lore.kernel.org/r/1420063.1690904933@warthog.procyon.org.uk
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
sk_getsockopt() runs locklessly. This means sk->sk_priority
can be read while other threads are changing its value.
Other reads also happen without socket lock being held.
Add missing annotations where needed.
Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
sk->sk_mark is often read while another thread could change the value.
Fixes: 4a19ec5800 ("[NET]: Introducing socket mark socket option.")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch fixes a misuse of IP{6}CB(skb) in GRO, while calling to
`udp6_lib_lookup2` when handling udp tunnels. `udp6_lib_lookup2` fetch the
device from CB. The fix changes it to fetch the device from `skb->dev`.
l3mdev case requires special attention since it has a master and a slave
device.
Fixes: a6024562ff ("udp: Add GRO functions to UDP socket")
Reported-by: Gal Pressman <gal@nvidia.com>
Signed-off-by: Richard Gobert <richardbgobert@gmail.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
do_tcp_getsockopt() and reqsk_timer_handler() read
icsk->icsk_syn_retries while another cpu might change its value.
Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Link: https://lore.kernel.org/r/20230719212857.3943972-7-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
do_tcp_getsockopt() reads tp->tcp_tx_delay while another cpu
might change its value.
Fixes: a842fe1425 ("tcp: add optional per socket transmit delay")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Link: https://lore.kernel.org/r/20230719212857.3943972-2-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
This reverts commit 3f4ca5fafc.
Commit 3f4ca5fafc ("tcp: avoid the lookup process failing to get sk in
ehash table") reversed the order in how a socket is inserted into ehash
to fix an issue that ehash-lookup could fail when reqsk/full sk/twsk are
swapped. However, it introduced another lookup failure.
The full socket in ehash is allocated from a slab with SLAB_TYPESAFE_BY_RCU
and does not have SOCK_RCU_FREE, so the socket could be reused even while
it is being referenced on another CPU doing RCU lookup.
Let's say a socket is reused and inserted into the same hash bucket during
lookup. After the blamed commit, a new socket is inserted at the end of
the list. If that happens, we will skip sockets placed after the previous
position of the reused socket, resulting in ehash lookup failure.
As described in Documentation/RCU/rculist_nulls.rst, we should insert a
new socket at the head of the list to avoid such an issue.
This issue, the swap-lookup-failure, and another variant reported in [0]
can all be handled properly by adding a locked ehash lookup suggested by
Eric Dumazet [1].
However, this issue could occur for every packet, thus more likely than
the other two races, so let's revert the change for now.
Link: https://lore.kernel.org/netdev/20230606064306.9192-1-duanmuquan@baidu.com/ [0]
Link: https://lore.kernel.org/netdev/CANn89iK8snOz8TYOhhwfimC7ykYA78GA3Nyv8x06SZYa1nKdyA@mail.gmail.com/ [1]
Fixes: 3f4ca5fafc ("tcp: avoid the lookup process failing to get sk in ehash table")
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Link: https://lore.kernel.org/r/20230717215918.15723-1-kuniyu@amazon.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
goto free_skb if an unexpected result is returned by pskb_tirm()
in erspan_xmit().
Signed-off-by: Yuanjun Gong <ruc_gongyuanjun@163.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
goto err_free_skb if an unexpected result is returned by pskb_tirm()
in erspan_fb_xmit().
Signed-off-by: Yuanjun Gong <ruc_gongyuanjun@163.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
key might contain private part of the key, so better use
kfree_sensitive to free it.
Fixes: 38320c70d2 ("[IPSEC]: Use crypto_aead and authenc in ESP")
Signed-off-by: Wang Ming <machel@vivo.com>
Reviewed-by: Tariq Toukan <tariqt@nvidia.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Commit 1fd54773c2 ("udp: allow header check for dodgy GSO_UDP_L4
packets.") checks DODGY bit for UDP, but for packets that can be fed
directly to the device after gso_segs reset, it actually falls through
to fragmentation:
https://lore.kernel.org/all/CAJPywTKDdjtwkLVUW6LRA2FU912qcDmQOQGt2WaDo28KzYDg+A@mail.gmail.com/
This change restores the expected behavior of GSO_UDP_L4 packets.
Fixes: 1fd54773c2 ("udp: allow header check for dodgy GSO_UDP_L4 packets.")
Suggested-by: Willem de Bruijn <willemdebruijn.kernel@gmail.com>
Signed-off-by: Yan Zhai <yan@cloudflare.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
request sockets are lockless, __tcp_oow_rate_limited() could be called
on the same object from different cpus. This is harmless.
Add READ_ONCE()/WRITE_ONCE() annotations to avoid a KCSAN report.
Fixes: 4ce7e93cb3 ("tcp: rate limit ACK sent by SYN_RECV request sockets")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
As MSG_SENDPAGE_NOTLAST is being phased out along with sendpage(), don't
use it further in than the sendpage methods, but rather translate it to
MSG_MORE and use that instead.
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Willem de Bruijn <willemdebruijn.kernel@gmail.com>
cc: Bernard Metzler <bmt@zurich.ibm.com>
cc: Jason Gunthorpe <jgg@ziepe.ca>
cc: Leon Romanovsky <leon@kernel.org>
cc: John Fastabend <john.fastabend@gmail.com>
cc: Jakub Sitnicki <jakub@cloudflare.com>
cc: David Ahern <dsahern@kernel.org>
cc: Karsten Graul <kgraul@linux.ibm.com>
cc: Wenjia Zhang <wenjia@linux.ibm.com>
cc: Jan Karcher <jaka@linux.ibm.com>
cc: "D. Wythe" <alibuda@linux.alibaba.com>
cc: Tony Lu <tonylu@linux.alibaba.com>
cc: Wen Gu <guwen@linux.alibaba.com>
cc: Boris Pismenny <borisp@nvidia.com>
cc: Steffen Klassert <steffen.klassert@secunet.com>
cc: Herbert Xu <herbert@gondor.apana.org.au>
Link: https://lore.kernel.org/r/20230623225513.2732256-2-dhowells@redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Even when tcp_splice_read() reads all it was asked for, for blocking
sockets it'll release and immediately regrab the socket lock, loop
around and break on the while check.
Check tss.len right after we adjust it, and return if we're done.
That saves us one release_sock(); lock_sock(); pair per successful
blocking splice read.
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://lore.kernel.org/r/80736a2cc6d478c383ea565ba825eaf4d1abd876.1687523671.git.asml.silence@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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Merge tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Daniel Borkmann says:
====================
pull-request: bpf-next 2023-06-23
We've added 49 non-merge commits during the last 24 day(s) which contain
a total of 70 files changed, 1935 insertions(+), 442 deletions(-).
The main changes are:
1) Extend bpf_fib_lookup helper to allow passing the route table ID,
from Louis DeLosSantos.
2) Fix regsafe() in verifier to call check_ids() for scalar registers,
from Eduard Zingerman.
3) Extend the set of cpumask kfuncs with bpf_cpumask_first_and()
and a rework of bpf_cpumask_any*() kfuncs. Additionally,
add selftests, from David Vernet.
4) Fix socket lookup BPF helpers for tc/XDP to respect VRF bindings,
from Gilad Sever.
5) Change bpf_link_put() to use workqueue unconditionally to fix it
under PREEMPT_RT, from Sebastian Andrzej Siewior.
6) Follow-ups to address issues in the bpf_refcount shared ownership
implementation, from Dave Marchevsky.
7) A few general refactorings to BPF map and program creation permissions
checks which were part of the BPF token series, from Andrii Nakryiko.
8) Various fixes for benchmark framework and add a new benchmark
for BPF memory allocator to BPF selftests, from Hou Tao.
9) Documentation improvements around iterators and trusted pointers,
from Anton Protopopov.
10) Small cleanup in verifier to improve allocated object check,
from Daniel T. Lee.
11) Improve performance of bpf_xdp_pointer() by avoiding access
to shared_info when XDP packet does not have frags,
from Jesper Dangaard Brouer.
12) Silence a harmless syzbot-reported warning in btf_type_id_size(),
from Yonghong Song.
13) Remove duplicate bpfilter_umh_cleanup in favor of umd_cleanup_helper,
from Jarkko Sakkinen.
14) Fix BPF selftests build for resolve_btfids under custom HOSTCFLAGS,
from Viktor Malik.
* tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (49 commits)
bpf, docs: Document existing macros instead of deprecated
bpf, docs: BPF Iterator Document
selftests/bpf: Fix compilation failure for prog vrf_socket_lookup
selftests/bpf: Add vrf_socket_lookup tests
bpf: Fix bpf socket lookup from tc/xdp to respect socket VRF bindings
bpf: Call __bpf_sk_lookup()/__bpf_skc_lookup() directly via TC hookpoint
bpf: Factor out socket lookup functions for the TC hookpoint.
selftests/bpf: Set the default value of consumer_cnt as 0
selftests/bpf: Ensure that next_cpu() returns a valid CPU number
selftests/bpf: Output the correct error code for pthread APIs
selftests/bpf: Use producer_cnt to allocate local counter array
xsk: Remove unused inline function xsk_buff_discard()
bpf: Keep BPF_PROG_LOAD permission checks clear of validations
bpf: Centralize permissions checks for all BPF map types
bpf: Inline map creation logic in map_create() function
bpf: Move unprivileged checks into map_create() and bpf_prog_load()
bpf: Remove in_atomic() from bpf_link_put().
selftests/bpf: Verify that check_ids() is used for scalars in regsafe()
bpf: Verify scalar ids mapping in regsafe() using check_ids()
selftests/bpf: Check if mark_chain_precision() follows scalar ids
...
====================
Link: https://lore.kernel.org/r/20230623211256.8409-1-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Per-VMA locking allows us to lock a struct vm_area_struct without
taking the process-wide mmap lock in read mode.
Consider a process workload where the mmap lock is taken constantly in
write mode. In this scenario, all zerocopy receives are periodically
blocked during that period of time - though in principle, the memory
ranges being used by TCP are not touched by the operations that need
the mmap write lock. This results in performance degradation.
Now consider another workload where the mmap lock is never taken in
write mode, but there are many TCP connections using receive zerocopy
that are concurrently receiving. These connections all take the mmap
lock in read mode, but this does induce a lot of contention and atomic
ops for this process-wide lock. This results in additional CPU
overhead caused by contending on the cache line for this lock.
However, with per-vma locking, both of these problems can be avoided.
As a test, I ran an RPC-style request/response workload with 4KB
payloads and receive zerocopy enabled, with 100 simultaneous TCP
connections. I measured perf cycles within the
find_tcp_vma/mmap_read_lock/mmap_read_unlock codepath, with and
without per-vma locking enabled.
When using process-wide mmap semaphore read locking, about 1% of
measured perf cycles were within this path. With per-VMA locking, this
value dropped to about 0.45%.
Signed-off-by: Arjun Roy <arjunroy@google.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Under certain circumstances, the tcp receive buffer memory limit
set by autotuning (sk_rcvbuf) is increased due to incoming data
packets as a result of the window not closing when it should be.
This can result in the receive buffer growing all the way up to
tcp_rmem[2], even for tcp sessions with a low BDP.
To reproduce: Connect a TCP session with the receiver doing
nothing and the sender sending small packets (an infinite loop
of socket send() with 4 bytes of payload with a sleep of 1 ms
in between each send()). This will cause the tcp receive buffer
to grow all the way up to tcp_rmem[2].
As a result, a host can have individual tcp sessions with receive
buffers of size tcp_rmem[2], and the host itself can reach tcp_mem
limits, causing the host to go into tcp memory pressure mode.
The fundamental issue is the relationship between the granularity
of the window scaling factor and the number of byte ACKed back
to the sender. This problem has previously been identified in
RFC 7323, appendix F [1].
The Linux kernel currently adheres to never shrinking the window.
In addition to the overallocation of memory mentioned above, the
current behavior is functionally incorrect, because once tcp_rmem[2]
is reached when no remediations remain (i.e. tcp collapse fails to
free up any more memory and there are no packets to prune from the
out-of-order queue), the receiver will drop in-window packets
resulting in retransmissions and an eventual timeout of the tcp
session. A receive buffer full condition should instead result
in a zero window and an indefinite wait.
In practice, this problem is largely hidden for most flows. It
is not applicable to mice flows. Elephant flows can send data
fast enough to "overrun" the sk_rcvbuf limit (in a single ACK),
triggering a zero window.
But this problem does show up for other types of flows. Examples
are websockets and other type of flows that send small amounts of
data spaced apart slightly in time. In these cases, we directly
encounter the problem described in [1].
RFC 7323, section 2.4 [2], says there are instances when a retracted
window can be offered, and that TCP implementations MUST ensure
that they handle a shrinking window, as specified in RFC 1122,
section 4.2.2.16 [3]. All prior RFCs on the topic of tcp window
management have made clear that sender must accept a shrunk window
from the receiver, including RFC 793 [4] and RFC 1323 [5].
This patch implements the functionality to shrink the tcp window
when necessary to keep the right edge within the memory limit by
autotuning (sk_rcvbuf). This new functionality is enabled with
the new sysctl: net.ipv4.tcp_shrink_window
Additional information can be found at:
https://blog.cloudflare.com/unbounded-memory-usage-by-tcp-for-receive-buffers-and-how-we-fixed-it/
[1] https://www.rfc-editor.org/rfc/rfc7323#appendix-F
[2] https://www.rfc-editor.org/rfc/rfc7323#section-2.4
[3] https://www.rfc-editor.org/rfc/rfc1122#page-91
[4] https://www.rfc-editor.org/rfc/rfc793
[5] https://www.rfc-editor.org/rfc/rfc1323
Signed-off-by: Mike Freemon <mfreemon@cloudflare.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Splicing to SOCK_RAW sockets may set MSG_SPLICE_PAGES, but in such a case,
__ip_append_data() will call skb_splice_from_iter() to access the 'from'
data, assuming it to point to a msghdr struct with an iter, instead of
using the provided getfrag function to access it.
In the case of raw_sendmsg(), however, this is not the case and 'from' will
point to a raw_frag_vec struct and raw_getfrag() will be the frag-getting
function. A similar issue may occur with rawv6_sendmsg().
Fix this by ignoring MSG_SPLICE_PAGES if getfrag != ip_generic_getfrag as
ip_generic_getfrag() expects "from" to be a msghdr*, but the other getfrags
don't. Note that this will prevent MSG_SPLICE_PAGES from being effective
for udplite.
This likely affects ping sockets too. udplite looks like it should be okay
as it expects "from" to be a msghdr.
Signed-off-by: David Howells <dhowells@redhat.com>
Reported-by: syzbot+d8486855ef44506fd675@syzkaller.appspotmail.com
Link: https://lore.kernel.org/r/000000000000ae4cbf05fdeb8349@google.com/
Fixes: 2dc334f1a6 ("splice, net: Use sendmsg(MSG_SPLICE_PAGES) rather than ->sendpage()")
Tested-by: syzbot+d8486855ef44506fd675@syzkaller.appspotmail.com
cc: David Ahern <dsahern@kernel.org>
cc: Jens Axboe <axboe@kernel.dk>
cc: Matthew Wilcox <willy@infradead.org>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Link: https://lore.kernel.org/r/1410156.1686729856@warthog.procyon.org.uk
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
With offloading enabled, esp_xmit() gets invoked very late, from within
validate_xmit_xfrm() which is after validate_xmit_skb() validates and
linearizes the skb if the underlying device does not support fragments.
esp_output_tail() may add a fragment to the skb while adding the auth
tag/ IV. Devices without the proper support will then send skb->data
points to with the correct length so the packet will have garbage at the
end. A pcap sniffer will claim that the proper data has been sent since
it parses the skb properly.
It is not affected with INET_ESP_OFFLOAD disabled.
Linearize the skb after offloading if the sending hardware requires it.
It was tested on v4, v6 has been adopted.
Fixes: 7785bba299 ("esp: Add a software GRO codepath")
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Most of the ioctls to net protocols operates directly on userspace
argument (arg). Usually doing get_user()/put_user() directly in the
ioctl callback. This is not flexible, because it is hard to reuse these
functions without passing userspace buffers.
Change the "struct proto" ioctls to avoid touching userspace memory and
operate on kernel buffers, i.e., all protocol's ioctl callbacks is
adapted to operate on a kernel memory other than on userspace (so, no
more {put,get}_user() and friends being called in the ioctl callback).
This changes the "struct proto" ioctl format in the following way:
int (*ioctl)(struct sock *sk, int cmd,
- unsigned long arg);
+ int *karg);
(Important to say that this patch does not touch the "struct proto_ops"
protocols)
So, the "karg" argument, which is passed to the ioctl callback, is a
pointer allocated to kernel space memory (inside a function wrapper).
This buffer (karg) may contain input argument (copied from userspace in
a prep function) and it might return a value/buffer, which is copied
back to userspace if necessary. There is not one-size-fits-all format
(that is I am using 'may' above), but basically, there are three type of
ioctls:
1) Do not read from userspace, returns a result to userspace
2) Read an input parameter from userspace, and does not return anything
to userspace
3) Read an input from userspace, and return a buffer to userspace.
The default case (1) (where no input parameter is given, and an "int" is
returned to userspace) encompasses more than 90% of the cases, but there
are two other exceptions. Here is a list of exceptions:
* Protocol RAW:
* cmd = SIOCGETVIFCNT:
* input and output = struct sioc_vif_req
* cmd = SIOCGETSGCNT
* input and output = struct sioc_sg_req
* Explanation: for the SIOCGETVIFCNT case, userspace passes the input
argument, which is struct sioc_vif_req. Then the callback populates
the struct, which is copied back to userspace.
* Protocol RAW6:
* cmd = SIOCGETMIFCNT_IN6
* input and output = struct sioc_mif_req6
* cmd = SIOCGETSGCNT_IN6
* input and output = struct sioc_sg_req6
* Protocol PHONET:
* cmd == SIOCPNADDRESOURCE | SIOCPNDELRESOURCE
* input int (4 bytes)
* Nothing is copied back to userspace.
For the exception cases, functions sock_sk_ioctl_inout() will
copy the userspace input, and copy it back to kernel space.
The wrapper that prepare the buffer and put the buffer back to user is
sk_ioctl(), so, instead of calling sk->sk_prot->ioctl(), the callee now
calls sk_ioctl(), which will handle all cases.
Signed-off-by: Breno Leitao <leitao@debian.org>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Link: https://lore.kernel.org/r/20230609152800.830401-1-leitao@debian.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Recently syzkaller reported a 7-year-old null-ptr-deref [0] that occurs
when a UDP-Lite socket tries to allocate a buffer under memory pressure.
Someone should have stumbled on the bug much earlier if UDP-Lite had been
used in a real app. Also, we do not always need a large UDP-Lite workload
to hit the bug since UDP and UDP-Lite share the same memory accounting
limit.
Removing UDP-Lite would simplify UDP code removing a bunch of conditionals
in fast path.
Let's add a deprecation notice when UDP-Lite socket is created and schedule
its removal to 2025.
Link: https://lore.kernel.org/netdev/20230523163305.66466-1-kuniyu@amazon.com/ [0]
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Make tcp_bpf_sendpage() a wrapper around tcp_bpf_sendmsg(MSG_SPLICE_PAGES)
rather than a loop calling tcp_sendpage(). sendpage() will be removed in
the future.
Signed-off-by: David Howells <dhowells@redhat.com>
cc: John Fastabend <john.fastabend@gmail.com>
cc: Jakub Sitnicki <jakub@cloudflare.com>
cc: Jens Axboe <axboe@kernel.dk>
cc: Matthew Wilcox <willy@infradead.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Now all tcp_stream_alloc_skb() callers pass @size == 0, we can
remove this parameter.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Now all skbs in write queue do not contain any payload in skb->head,
we can remove some dead code.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
tcp_send_syn_data() is the last component in TCP transmit
path to put payload in skb->head.
Switch it to use page frags, so that we can remove dead
code later.
This allows to put more payload than previous implementation.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Move declarations into include/net/gso.h and code into net/core/gso.c
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Stanislav Fomichev <sdf@google.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://lore.kernel.org/r/20230608191738.3947077-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Before Linux v5.8 an AF_INET6 SOCK_DGRAM (udp/udplite) socket
with SOL_UDP, UDP_ENCAP, UDP_ENCAP_ESPINUDP{,_NON_IKE} enabled
would just unconditionally use xfrm4_udp_encap_rcv(), afterwards
such a socket would use the newly added xfrm6_udp_encap_rcv()
which only handles IPv6 packets.
Cc: Sabrina Dubroca <sd@queasysnail.net>
Cc: Steffen Klassert <steffen.klassert@secunet.com>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Benedict Wong <benedictwong@google.com>
Cc: Yan Yan <evitayan@google.com>
Fixes: 0146dca70b ("xfrm: add support for UDPv6 encapsulation of ESP")
Signed-off-by: Maciej Żenczykowski <maze@google.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Reviewed-by: Sabrina Dubroca <sd@queasysnail.net>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Allow splice to undo the effects of MSG_MORE after prematurely ending a
splice/sendfile due to getting an EOF condition (->splice_read() returned
0) after splice had called sendmsg() with MSG_MORE set when the user didn't
set MSG_MORE.
For UDP, a pending packet will not be emitted if the socket is closed
before it is flushed; with this change, it be flushed by ->splice_eof().
For TCP, it's not clear that MSG_MORE is actually effective.
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Link: https://lore.kernel.org/r/CAHk-=wh=V579PDYvkpnTobCLGczbgxpMgGmmhqiTyE34Cpi5Gg@mail.gmail.com/
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Kuniyuki Iwashima <kuniyu@amazon.com>
cc: Willem de Bruijn <willemdebruijn.kernel@gmail.com>
cc: David Ahern <dsahern@kernel.org>
cc: Jens Axboe <axboe@kernel.dk>
cc: Matthew Wilcox <willy@infradead.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
tcp_mtu_probe() is still copying payload from skbs in the write queue,
using skb_copy_bits(), ignoring potential errors.
Modern TCP stack wants to only deal with payload found in page frags,
as this is a prereq for TCPDirect (host stack might not have access
to the payload)
Signed-off-by: Eric Dumazet <edumazet@google.com>
Link: https://lore.kernel.org/r/20230607214113.1992947-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Cross-merge networking fixes after downstream PR.
Conflicts:
net/sched/sch_taprio.c
d636fc5dd6 ("net: sched: add rcu annotations around qdisc->qdisc_sleeping")
dced11ef84 ("net/sched: taprio: don't overwrite "sch" variable in taprio_dump_class_stats()")
net/ipv4/sysctl_net_ipv4.c
e209fee411 ("net/ipv4: ping_group_range: allow GID from 2147483648 to 4294967294")
ccce324dab ("tcp: make the first N SYN RTO backoffs linear")
https://lore.kernel.org/all/20230605100816.08d41a7b@canb.auug.org.au/
No adjacent changes.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
