This improves the fix for CVE-2026-43500.
Fix the pagecache corruption from in-place decryption of a DATA packet
transmitted locally by splice() by getting rid of the packet sharing in the
I/O thread and unconditionally extracting the packet content into a bounce
buffer in which the buffer is decrypted. recvmsg() (or the kernel
equivalent) then copies the data from the bounce buffer to the destination
buffer. The sk_buff then remains unmodified.
This has an additional advantage in that the packet is then arranged in the
buffer with the correct alignment required for the crypto algorithms to
process directly. The performance of the crypto does seem to be a little
faster and, surprisingly, the unencrypted performance doesn't seem to
change much - possibly due to removing complexity from the I/O thread.
Yet another advantage is that the I/O thread doesn't have to copy packets
which would slow down packet distribution, ACK generation, etc..
The buffer belongs to the call and is allocated initially at 2K,
sufficiently large to hold a whole jumbo subpacket, but the buffer will be
increased in size if needed. However, to take this work, MSG_PEEK may
cause a later packet to be decrypted into the buffer, in which case the
earlier one will need re-decrypting for a subsequent recvmsg().
Note that rx_pkt_offset may legitimately see 0 as a valid offset now, so
switch to using USHRT_MAX to indicate an invalid offset.
Note also that I would generally prefer to replace the buffers of the
current sk_buff with a new kmalloc'd buffer of the right size, ditching the
old data and frags as this makes the handling of MSG_PEEK easier and
removes the re-decryption issue, but this looks like quite a complicated
thing to achieve. skb_morph() looks half way to what I want, but I don't
want to have to allocate a new sk_buff.
Fixes: d0d5c0cd1e ("rxrpc: Use skb_unshare() rather than skb_cow_data()")
Reported-by: Hyunwoo Kim <imv4bel@gmail.com>
Closes: https://lore.kernel.org/r/afKV2zGR6rrelPC7@v4bel/
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Simon Horman <horms@kernel.org>
cc: Jiayuan Chen <jiayuan.chen@linux.dev>
cc: linux-afs@lists.infradead.org
Reviewed-by: Jeffrey Altman <jaltman@auristor.com>
Tested-by: Marc Dionne <marc.dionne@auristor.com>
Link: https://patch.msgid.link/20260515230516.2718212-3-dhowells@redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
The DATA-packet handler in rxrpc_input_call_event() and the RESPONSE
handler in rxrpc_verify_response() copy the skb to a linear one before
calling into the security ops only when skb_cloned() is true. An skb
that is not cloned but still carries externally-owned paged fragments
(e.g. SKBFL_SHARED_FRAG set by splice() into a UDP socket via
__ip_append_data, or a chained skb_has_frag_list()) falls through to
the in-place decryption path, which binds the frag pages directly into
the AEAD/skcipher SGL via skb_to_sgvec().
Extend the gate to also unshare when skb_has_frag_list() or
skb_has_shared_frag() is true. This catches the splice-loopback vector
and other externally-shared frag sources while preserving the
zero-copy fast path for skbs whose frags are kernel-private (e.g. NIC
page_pool RX, GRO). The OOM/trace handling already in place is reused.
Fixes: d0d5c0cd1e ("rxrpc: Use skb_unshare() rather than skb_cow_data()")
Cc: stable@vger.kernel.org
Signed-off-by: Hyunwoo Kim <imv4bel@gmail.com>
Reviewed-by: Jiayuan Chen <jiayuan.chen@linux.dev>
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
In rxrpc_preparse(), there are two paths for parsing key payloads: the
XDR path (for large payloads) and the non-XDR path (for payloads <= 28
bytes). While the XDR path (rxrpc_preparse_xdr_rxkad()) correctly
validates the ticket length against AFSTOKEN_RK_TIX_MAX, the non-XDR
path fails to do so.
This allows an unprivileged user to provide a very large ticket length.
When this key is later read via rxrpc_read(), the total
token size (toksize) calculation results in a value that exceeds
AFSTOKEN_LENGTH_MAX, triggering a WARN_ON().
[ 2001.302904] WARNING: CPU: 2 PID: 2108 at net/rxrpc/key.c:778 rxrpc_read+0x109/0x5c0 [rxrpc]
Fix this by adding a check in the non-XDR parsing path of rxrpc_preparse()
to ensure the ticket length does not exceed AFSTOKEN_RK_TIX_MAX,
bringing it into parity with the XDR parsing logic.
Fixes: 8a7a3eb4dd ("KEYS: RxRPC: Use key preparsing")
Fixes: 84924aac08 ("rxrpc: Fix checker warning")
Reported-by: Anderson Nascimento <anderson@allelesecurity.com>
Signed-off-by: Anderson Nascimento <anderson@allelesecurity.com>
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Marc Dionne <marc.dionne@auristor.com>
cc: Jeffrey Altman <jaltman@auristor.com>
cc: Simon Horman <horms@kernel.org>
cc: linux-afs@lists.infradead.org
cc: stable@kernel.org
Link: https://patch.msgid.link/20260422161438.2593376-7-dhowells@redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
The AF_RXRPC procfs helpers format local and remote socket addresses into
fixed 50-byte stack buffers with "%pISpc".
That is too small for the longest current-tree IPv6-with-port form the
formatter can produce. In lib/vsprintf.c, the compressed IPv6 path uses a
dotted-quad tail not only for v4mapped addresses, but also for ISATAP
addresses via ipv6_addr_is_isatap().
As a result, a case such as
[ffff:ffff:ffff:ffff:0:5efe:255.255.255.255]:65535
is possible with the current formatter. That is 50 visible characters, so
51 bytes including the trailing NUL, which does not fit in the existing
char[50] buffers used by net/rxrpc/proc.c.
Size the buffers from the formatter's maximum textual form and switch the
call sites to scnprintf().
Changes since v1:
- correct the changelog to cite the actual maximum current-tree case
explicitly
- frame the proof around the ISATAP formatting path instead of the earlier
mapped-v4 example
Fixes: 75b54cb57c ("rxrpc: Add IPv6 support")
Signed-off-by: Pengpeng Hou <pengpeng@iscas.ac.cn>
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Marc Dionne <marc.dionne@auristor.com>
cc: Anderson Nascimento <anderson@allelesecurity.com>
cc: Simon Horman <horms@kernel.org>
cc: linux-afs@lists.infradead.org
cc: stable@kernel.org
Link: https://patch.msgid.link/20260408121252.2249051-22-dhowells@redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
An AF_RXRPC socket can be both client and server at the same time. When
sending new calls (ie. it's acting as a client), it uses rx->key to set the
security, and when accepting incoming calls (ie. it's acting as a server),
it uses rx->securities.
setsockopt(RXRPC_SECURITY_KEY) sets rx->key to point to an rxrpc-type key
and setsockopt(RXRPC_SECURITY_KEYRING) sets rx->securities to point to a
keyring of rxrpc_s-type keys.
Now, it should be possible to use both rx->key and rx->securities on the
same socket - but for userspace AF_RXRPC sockets rxrpc_setsockopt()
prevents that.
Fix this by:
(1) Remove the incorrect check rxrpc_setsockopt(RXRPC_SECURITY_KEYRING)
makes on rx->key.
(2) Move the check that rxrpc_setsockopt(RXRPC_SECURITY_KEY) makes on
rx->key down into rxrpc_request_key().
(3) Remove rxrpc_request_key()'s check on rx->securities.
This (in combination with a previous patch) pushes the checks down into the
functions that set those pointers and removes the cross-checks that prevent
both key and keyring being set.
Fixes: 17926a7932 ("[AF_RXRPC]: Provide secure RxRPC sockets for use by userspace and kernel both")
Closes: https://sashiko.dev/#/patchset/20260401105614.1696001-10-dhowells@redhat.com
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Marc Dionne <marc.dionne@auristor.com>
cc: Anderson Nascimento <anderson@allelesecurity.com>
cc: Luxiao Xu <rakukuip@gmail.com>
cc: Yuan Tan <yuantan098@gmail.com>
cc: Simon Horman <horms@kernel.org>
cc: linux-afs@lists.infradead.org
cc: stable@kernel.org
Link: https://patch.msgid.link/20260408121252.2249051-16-dhowells@redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
rxgk_verify_response() decodes auth_len from the packet and is supposed
to verify that it fits in the remaining bytes. The existing check is
inverted, so oversized RESPONSE authenticators are accepted and passed
to rxgk_decrypt_skb(), which can later reach skb_to_sgvec() with an
impossible length and hit BUG_ON(len).
Decoded from the original latest-net reproduction logs with
scripts/decode_stacktrace.sh:
RIP: __skb_to_sgvec()
[net/core/skbuff.c:5285 (discriminator 1)]
Call Trace:
skb_to_sgvec() [net/core/skbuff.c:5305]
rxgk_decrypt_skb() [net/rxrpc/rxgk_common.h:81]
rxgk_verify_response() [net/rxrpc/rxgk.c:1268]
rxrpc_process_connection()
[net/rxrpc/conn_event.c:266 net/rxrpc/conn_event.c:364
net/rxrpc/conn_event.c:386]
process_one_work() [kernel/workqueue.c:3281]
worker_thread()
[kernel/workqueue.c:3353 kernel/workqueue.c:3440]
kthread() [kernel/kthread.c:436]
ret_from_fork() [arch/x86/kernel/process.c:164]
Reject authenticator lengths that exceed the remaining packet payload.
Fixes: 9d1d2b5934 ("rxrpc: rxgk: Implement the yfs-rxgk security class (GSSAPI)")
Signed-off-by: Keenan Dong <keenanat2000@gmail.com>
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Marc Dionne <marc.dionne@auristor.com>
cc: Simon Horman <horms@kernel.org>
cc: Willy Tarreau <w@1wt.eu>
cc: linux-afs@lists.infradead.org
cc: stable@kernel.org
Link: https://patch.msgid.link/20260408121252.2249051-14-dhowells@redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
rxgk_verify_authenticator() copies auth_len bytes into a temporary
buffer and then passes p + auth_len as the parser limit to
rxgk_do_verify_authenticator(). Since p is a __be32 *, that inflates the
parser end pointer by a factor of four and lets malformed RESPONSE
authenticators read past the kmalloc() buffer.
Decoded from the original latest-net reproduction logs with
scripts/decode_stacktrace.sh:
BUG: KASAN: slab-out-of-bounds in rxgk_verify_response()
Call Trace:
dump_stack_lvl() [lib/dump_stack.c:123]
print_report() [mm/kasan/report.c:379 mm/kasan/report.c:482]
kasan_report() [mm/kasan/report.c:597]
rxgk_verify_response()
[net/rxrpc/rxgk.c:1103 net/rxrpc/rxgk.c:1167
net/rxrpc/rxgk.c:1274]
rxrpc_process_connection()
[net/rxrpc/conn_event.c:266 net/rxrpc/conn_event.c:364
net/rxrpc/conn_event.c:386]
process_one_work() [kernel/workqueue.c:3281]
worker_thread()
[kernel/workqueue.c:3353 kernel/workqueue.c:3440]
kthread() [kernel/kthread.c:436]
ret_from_fork() [arch/x86/kernel/process.c:164]
Allocated by task 54:
rxgk_verify_response()
[include/linux/slab.h:954 net/rxrpc/rxgk.c:1155
net/rxrpc/rxgk.c:1274]
rxrpc_process_connection()
[net/rxrpc/conn_event.c:266 net/rxrpc/conn_event.c:364
net/rxrpc/conn_event.c:386]
Convert the byte count to __be32 units before constructing the parser
limit.
Fixes: 9d1d2b5934 ("rxrpc: rxgk: Implement the yfs-rxgk security class (GSSAPI)")
Signed-off-by: Keenan Dong <keenanat2000@gmail.com>
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Marc Dionne <marc.dionne@auristor.com>
cc: Simon Horman <horms@kernel.org>
cc: Willy Tarreau <w@1wt.eu>
cc: linux-afs@lists.infradead.org
cc: stable@kernel.org
Link: https://patch.msgid.link/20260408121252.2249051-13-dhowells@redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
rxrpc_preparse_xdr_yfs_rxgk() reads the raw key length and ticket length
from the XDR token as u32 values and passes each through round_up(x, 4)
before using the rounded value for validation and allocation. When the raw
length is >= 0xfffffffd, round_up() wraps to 0, so the bounds check and
kzalloc both use 0 while the subsequent memcpy still copies the original
~4 GiB value, producing a heap buffer overflow reachable from an
unprivileged add_key() call.
Fix this by:
(1) Rejecting raw key lengths above AFSTOKEN_GK_KEY_MAX and raw ticket
lengths above AFSTOKEN_GK_TOKEN_MAX before rounding, consistent with
the caps that the RxKAD path already enforces via AFSTOKEN_RK_TIX_MAX.
(2) Sizing the flexible-array allocation from the validated raw key
length via struct_size_t() instead of the rounded value.
(3) Caching the raw lengths so that the later field assignments and
memcpy calls do not re-read from the token, eliminating a class of
TOCTOU re-parse.
The control path (valid token with lengths within bounds) is unaffected.
Fixes: 0ca100ff4d ("rxrpc: Add YFS RxGK (GSSAPI) security class")
Signed-off-by: Oleh Konko <security@1seal.org>
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Jeffrey Altman <jaltman@auristor.com>
cc: Marc Dionne <marc.dionne@auristor.com>
cc: Simon Horman <horms@kernel.org>
cc: linux-afs@lists.infradead.org
cc: stable@kernel.org
Link: https://patch.msgid.link/20260408121252.2249051-6-dhowells@redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Fix rxrpc call removal from the rxnet->calls list to use list_del_rcu()
rather than list_del_init() to prevent stuffing up reading
/proc/net/rxrpc/calls from potentially getting into an infinite loop.
This, however, means that list_empty() no longer works on an entry that's
been deleted from the list, making it harder to detect prior deletion. Fix
this by:
Firstly, make rxrpc_destroy_all_calls() only dump the first ten calls that
are unexpectedly still on the list. Limiting the number of steps means
there's no need to call cond_resched() or to remove calls from the list
here, thereby eliminating the need for rxrpc_put_call() to check for that.
rxrpc_put_call() can then be fixed to unconditionally delete the call from
the list as it is the only place that the deletion occurs.
Fixes: 2baec2c3f8 ("rxrpc: Support network namespacing")
Closes: https://sashiko.dev/#/patchset/20260319150150.4189381-1-dhowells%40redhat.com
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Marc Dionne <marc.dionne@auristor.com>
cc: Jeffrey Altman <jaltman@auristor.com>
cc: Linus Torvalds <torvalds@linux-foundation.org>
cc: Simon Horman <horms@kernel.org>
cc: linux-afs@lists.infradead.org
cc: stable@kernel.org
Link: https://patch.msgid.link/20260408121252.2249051-5-dhowells@redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
In rxrpc_new_client_call_for_sendmsg(), a key with no payload is meant to
be substituted for a NULL key pointer, but the variable this is done with
is subsequently not used.
Fix this by using "key" rather than "rx->key" when filling in the
connection parameters.
Note that this only affects direct use of AF_RXRPC; the kAFS filesystem
doesn't use sendmsg() directly and so bypasses the issue. Further,
AF_RXRPC passes a NULL key in if no key is set, so using an anonymous key
in that manner works. Since this hasn't been noticed to this point, it
might be better just to remove the "key" variable and the code that sets it
- and, arguably, rxrpc_init_client_call_security() would be a better place
to handle it.
Fixes: 19ffa01c9c ("rxrpc: Use structs to hold connection params and protocol info")
Closes: https://sashiko.dev/#/patchset/20260319150150.4189381-1-dhowells%40redhat.com
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Marc Dionne <marc.dionne@auristor.com>
cc: Jeffrey Altman <jaltman@auristor.com>
cc: Simon Horman <horms@kernel.org>
cc: linux-afs@lists.infradead.org
cc: stable@kernel.org
Link: https://patch.msgid.link/20260408121252.2249051-4-dhowells@redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Maintaining a modular IPv6 stack offers image size savings for specific
setups, this benefit is outweighed by the architectural burden it
imposes on the subsystems on implementation and maintenance. Therefore,
drop it.
Change CONFIG_IPV6 from tristate to bool. Remove all Kconfig
dependencies across the tree that explicitly checked for IPV6=m. In
addition, remove MODULE_DESCRIPTION(), MODULE_ALIAS(), MODULE_AUTHOR()
and MODULE_LICENSE().
This is also replacing module_init() by device_initcall(). It is not
possible to use fs_initcall() as IPv4 does because that creates a race
condition on IPv6 addrconf.
Finally, modify the default configs from CONFIG_IPV6=m to CONFIG_IPV6=y
except for m68k as according to the bloat-o-meter the image is
increasing by 330KB~ and that isn't acceptable. Instead, disable IPv6 on
this architecture by default. This is aligned with m68k RAM requirements
and recommendations [1].
[1] http://www.linux-m68k.org/faq/ram.html
Signed-off-by: Fernando Fernandez Mancera <fmancera@suse.de>
Tested-by: Ricardo B. Marlière <rbm@suse.com>
Acked-by: Krzysztof Kozlowski <krzk@kernel.org> # arm64
Link: https://patch.msgid.link/20260325120928.15848-2-fmancera@suse.de
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
As announced in commit be28c14ac8 ("udplite: Print deprecation
notice."), it's time to deprecate UDP-Lite.
As a first step, let's drop support for IPv6 UDP-Lite sockets.
We will remove the remaining dead code gradually.
Along with the removal of udplite.c, most of the functions exposed
via udp_impl.h are made static.
The prototypes of udpv6_sendmsg() and udpv6_recvmsg() are moved
to udp.h, but only udpv6_recvmsg() has INDIRECT_CALLABLE_DECLARE()
because udpv6_sendmsg() is exported for rxrpc since commit ed472b0c87
("rxrpc: Call udp_sendmsg() directly").
Also, udpv6_recvmsg() needs INDIRECT_CALLABLE_SCOPE for
CONFIG_MITIGATION_RETPOLINE=n.
Note that udplite.h is included temporarily for udplite_csum().
Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Link: https://patch.msgid.link/20260311052020.1213705-3-kuniyu@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
This was done entirely with mindless brute force, using
git grep -l '\<k[vmz]*alloc_objs*(.*, GFP_KERNEL)' |
xargs sed -i 's/\(alloc_objs*(.*\), GFP_KERNEL)/\1)/'
to convert the new alloc_obj() users that had a simple GFP_KERNEL
argument to just drop that argument.
Note that due to the extreme simplicity of the scripting, any slightly
more complex cases spread over multiple lines would not be triggered:
they definitely exist, but this covers the vast bulk of the cases, and
the resulting diff is also then easier to check automatically.
For the same reason the 'flex' versions will be done as a separate
conversion.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This is the result of running the Coccinelle script from
scripts/coccinelle/api/kmalloc_objs.cocci. The script is designed to
avoid scalar types (which need careful case-by-case checking), and
instead replace kmalloc-family calls that allocate struct or union
object instances:
Single allocations: kmalloc(sizeof(TYPE), ...)
are replaced with: kmalloc_obj(TYPE, ...)
Array allocations: kmalloc_array(COUNT, sizeof(TYPE), ...)
are replaced with: kmalloc_objs(TYPE, COUNT, ...)
Flex array allocations: kmalloc(struct_size(PTR, FAM, COUNT), ...)
are replaced with: kmalloc_flex(*PTR, FAM, COUNT, ...)
(where TYPE may also be *VAR)
The resulting allocations no longer return "void *", instead returning
"TYPE *".
Signed-off-by: Kees Cook <kees@kernel.org>
Fix the following:
BUG: KCSAN: data-race in rxrpc_peer_keepalive_worker / rxrpc_send_data_packet
which is reporting an issue with the reads and writes to ->last_tx_at in:
conn->peer->last_tx_at = ktime_get_seconds();
and:
keepalive_at = peer->last_tx_at + RXRPC_KEEPALIVE_TIME;
The lockless accesses to these to values aren't actually a problem as the
read only needs an approximate time of last transmission for the purposes
of deciding whether or not the transmission of a keepalive packet is
warranted yet.
Also, as ->last_tx_at is a 64-bit value, tearing can occur on a 32-bit
arch.
Fix both of these by switching to an unsigned int for ->last_tx_at and only
storing the LSW of the time64_t. It can then be reconstructed at need
provided no more than 68 years has elapsed since the last transmission.
Fixes: ace45bec6d ("rxrpc: Fix firewall route keepalive")
Reported-by: syzbot+6182afad5045e6703b3d@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/r/695e7cfb.050a0220.1c677c.036b.GAE@google.com/
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Marc Dionne <marc.dionne@auristor.com>
cc: Simon Horman <horms@kernel.org>
cc: linux-afs@lists.infradead.org
cc: stable@kernel.org
Link: https://patch.msgid.link/1107124.1768903985@warthog.procyon.org.uk
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
If rxrpc_recvmsg() fails because MSG_DONTWAIT was specified but the call at
the front of the recvmsg queue already has its mutex locked, it requeues
the call - whether or not the call is already queued. The call may be on
the queue because MSG_PEEK was also passed and so the call was not dequeued
or because the I/O thread requeued it.
The unconditional requeue may then corrupt the recvmsg queue, leading to
things like UAFs or refcount underruns.
Fix this by only requeuing the call if it isn't already on the queue - and
moving it to the front if it is already queued. If we don't queue it, we
have to put the ref we obtained by dequeuing it.
Also, MSG_PEEK doesn't dequeue the call so shouldn't call
rxrpc_notify_socket() for the call if we didn't use up all the data on the
queue, so fix that also.
Fixes: 540b1c48c3 ("rxrpc: Fix deadlock between call creation and sendmsg/recvmsg")
Reported-by: Faith <faith@zellic.io>
Reported-by: Pumpkin Chang <pumpkin@devco.re>
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Marc Dionne <marc.dionne@auristor.com>
cc: Nir Ohfeld <niro@wiz.io>
cc: Willy Tarreau <w@1wt.eu>
cc: Simon Horman <horms@kernel.org>
cc: linux-afs@lists.infradead.org
cc: stable@kernel.org
Link: https://patch.msgid.link/95163.1768428203@warthog.procyon.org.uk
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Update all struct proto_ops connect() callback function prototypes from
"struct sockaddr *" to "struct sockaddr_unsized *" to avoid lying to the
compiler about object sizes. Calls into struct proto handlers gain casts
that will be removed in the struct proto conversion patch.
No binary changes expected.
Signed-off-by: Kees Cook <kees@kernel.org>
Link: https://patch.msgid.link/20251104002617.2752303-3-kees@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Update all struct proto_ops bind() callback function prototypes from
"struct sockaddr *" to "struct sockaddr_unsized *" to avoid lying to the
compiler about object sizes. Calls into struct proto handlers gain casts
that will be removed in the struct proto conversion patch.
No binary changes expected.
Signed-off-by: Kees Cook <kees@kernel.org>
Link: https://patch.msgid.link/20251104002617.2752303-2-kees@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Currently if a user enqueue a work item using schedule_delayed_work() the
used wq is "system_wq" (per-cpu wq) while queue_delayed_work() use
WORK_CPU_UNBOUND (used when a cpu is not specified). The same applies to
schedule_work() that is using system_wq and queue_work(), that makes use
again of WORK_CPU_UNBOUND.
This lack of consistentcy cannot be addressed without refactoring the API.
alloc_workqueue() treats all queues as per-CPU by default, while unbound
workqueues must opt-in via WQ_UNBOUND.
This default is suboptimal: most workloads benefit from unbound queues,
allowing the scheduler to place worker threads where they’re needed and
reducing noise when CPUs are isolated.
This change adds a new WQ_PERCPU flag at the network subsystem, to explicitly
request the use of the per-CPU behavior. Both flags coexist for one release
cycle to allow callers to transition their calls.
Once migration is complete, WQ_UNBOUND can be removed and unbound will
become the implicit default.
With the introduction of the WQ_PERCPU flag (equivalent to !WQ_UNBOUND),
any alloc_workqueue() caller that doesn’t explicitly specify WQ_UNBOUND
must now use WQ_PERCPU.
All existing users have been updated accordingly.
Suggested-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Marco Crivellari <marco.crivellari@suse.com>
Link: https://patch.msgid.link/20250918142427.309519-4-marco.crivellari@suse.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
