Commit Graph

10161 Commits

Author SHA1 Message Date
Jakub Kicinski
4e655028c2 net: ethtool: remove the compat code for _rxfh_context ops
All drivers are now converted to dedicated _rxfh_context ops.
Remove the use of >set_rxfh() to manage additional contexts.

Reviewed-by: Gal Pressman <gal@nvidia.com>
Reviewed-by: Edward Cree <ecree.xilinx@gmail.com>
Link: https://patch.msgid.link/20250707184115.2285277-5-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-07-08 11:56:40 -07:00
Fengyuan Gong
a41851bea7 net: account for encap headers in qdisc pkt len
Refine qdisc_pkt_len_init to include headers up through
the inner transport header when computing header size
for encapsulations. Also refine net/sched/sch_cake.c
borrowed from qdisc_pkt_len_init().

Signed-off-by: Fengyuan Gong <gfengyuan@google.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Acked-by: Toke Høiland-Jørgensen <toke@redhat.com>
Link: https://patch.msgid.link/20250702160741.1204919-1-gfengyuan@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-07-08 08:55:33 -07:00
Michal Luczaj
ab34e14258 net: skbuff: Drop unused @skb
Since its introduction in commit 6fa01ccd88 ("skbuff: Add pskb_extract()
helper function"), pskb_carve_frag_list() never used the argument @skb.
Drop it and adapt the only caller.

No functional change intended.

Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: Michal Luczaj <mhal@rbox.co>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-07-08 08:37:22 -07:00
Michal Luczaj
ad0ac6cd9c net: skbuff: Drop unused @skb
Since its introduction in commit ce098da149 ("skbuff: Introduce
slab_build_skb()"), __slab_build_skb() never used the @skb argument. Remove
it and adapt both callers.

No functional change intended.

Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: Michal Luczaj <mhal@rbox.co>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-07-08 08:37:22 -07:00
Michal Luczaj
25489a4f55 net: splice: Drop unused @gfp
Since its introduction in commit 2e910b9532 ("net: Add a function to
splice pages into an skbuff for MSG_SPLICE_PAGES"), skb_splice_from_iter()
never used the @gfp argument. Remove it and adapt callers.

No functional change intended.

Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: Michal Luczaj <mhal@rbox.co>
Link: https://patch.msgid.link/20250702-splice-drop-unused-v3-2-55f68b60d2b7@rbox.co
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-07-08 08:37:15 -07:00
Michal Luczaj
1024f12071 net: splice: Drop unused @pipe
Since commit 41c73a0d44 ("net: speedup skb_splice_bits()"),
__splice_segment() and spd_fill_page() do not use the @pipe argument. Drop
it.

While adapting the callers, move one line to enforce reverse xmas tree
order.

No functional change intended.

Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: Michal Luczaj <mhal@rbox.co>
Link: https://patch.msgid.link/20250702-splice-drop-unused-v3-1-55f68b60d2b7@rbox.co
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-07-08 08:37:14 -07:00
Breno Leitao
eb4e773f13 netpoll: move Ethernet setup to push_eth() helper
Refactor Ethernet header population into dedicated function, completing
the layered abstraction with:

- push_eth() for link layer
- push_udp() for transport
- push_ipv4()/push_ipv6() for network

Signed-off-by: Breno Leitao <leitao@debian.org>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20250702-netpoll_untagle_ip-v2-6-13cf3db24e2b@debian.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-07-07 18:52:56 -07:00
Breno Leitao
cacfb1f4e9 netpoll: factor out UDP header setup into push_udp() helper
Move UDP header construction from netpoll_send_udp() into a new
static helper function push_udp(). This completes the protocol
layer refactoring by:

1. Creating a dedicated helper for UDP header assembly
2. Removing UDP-specific logic from the main send function
3. Establishing a consistent pattern with existing IPv4/IPv6 helpers:
   - push_udp()
   - push_ipv4()
   - push_ipv6()

The change improves code organization and maintains the encapsulation
pattern established in previous refactorings.

Signed-off-by: Breno Leitao <leitao@debian.org>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20250702-netpoll_untagle_ip-v2-5-13cf3db24e2b@debian.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-07-07 18:52:56 -07:00
Breno Leitao
8c27639dbe netpoll: factor out IPv4 header setup into push_ipv4() helper
Move IPv4 header construction from netpoll_send_udp() into a new
static helper function push_ipv4(). This completes the refactoring
started with IPv6 header handling, creating symmetric helper functions
for both IP versions.

Changes include:
1. Extracting IPv4 header setup logic into push_ipv4()
2. Replacing inline IPv4 code with helper call
3. Moving eth assignment after helper calls for consistency

The refactoring reduces code duplication and improves maintainability
by isolating IP version-specific logic.

Signed-off-by: Breno Leitao <leitao@debian.org>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20250702-netpoll_untagle_ip-v2-4-13cf3db24e2b@debian.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-07-07 18:52:56 -07:00
Breno Leitao
839388f39a netpoll: factor out IPv6 header setup into push_ipv6() helper
Move IPv6 header construction from netpoll_send_udp() into a new
static helper function, push_ipv6(). This refactoring reduces code
duplication and improves readability in netpoll_send_udp().

Signed-off-by: Breno Leitao <leitao@debian.org>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20250702-netpoll_untagle_ip-v2-3-13cf3db24e2b@debian.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-07-07 18:52:55 -07:00
Breno Leitao
01dae7a61c netpoll: factor out UDP checksum calculation into helper
Extract UDP checksum calculation logic from netpoll_send_udp()
into a new static helper function netpoll_udp_checksum(). This
reduces code duplication and improves readability for both IPv4
and IPv6 cases.

No functional change intended.

Signed-off-by: Breno Leitao <leitao@debian.org>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20250702-netpoll_untagle_ip-v2-2-13cf3db24e2b@debian.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-07-07 18:52:55 -07:00
Breno Leitao
4b52cdfcce netpoll: Improve code clarity with explicit struct size calculations
Replace pointer-dereference sizeof() operations with explicit struct names
for improved readability and maintainability. This change:

1. Replaces `sizeof(*udph)` with `sizeof(struct udphdr)`
2. Replaces `sizeof(*ip6h)` with `sizeof(struct ipv6hdr)`
3. Replaces `sizeof(*iph)` with `sizeof(struct iphdr)`

This will make it easy to move code in the upcoming patches.

No functional changes are introduced by this patch.

Signed-off-by: Breno Leitao <leitao@debian.org>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20250702-netpoll_untagle_ip-v2-1-13cf3db24e2b@debian.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-07-07 18:52:55 -07:00
Eric Dumazet
6058099da5 net: remove RTNL use for /proc/sys/net/core/rps_default_mask
Use a dedicated mutex instead.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com>
Link: https://patch.msgid.link/20250702061558.1585870-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-07-07 18:42:12 -07:00
Byungchul Park
b56ce86846 page_pool: rename __page_pool_alloc_pages_slow() to __page_pool_alloc_netmems_slow()
Now that __page_pool_alloc_pages_slow() is for allocating netmem, not
struct page, rename it to __page_pool_alloc_netmems_slow() to reflect
what it does.

Signed-off-by: Byungchul Park <byungchul@sk.com>
Reviewed-by: Mina Almasry <almasrymina@google.com>
Reviewed-by: Toke Høiland-Jørgensen <toke@redhat.com>
Link: https://patch.msgid.link/20250702053256.4594-4-byungchul@sk.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-07-07 18:40:09 -07:00
Byungchul Park
4ad125ae38 page_pool: rename __page_pool_release_page_dma() to __page_pool_release_netmem_dma()
Now that __page_pool_release_page_dma() is for releasing netmem, not
struct page, rename it to __page_pool_release_netmem_dma() to reflect
what it does.

Signed-off-by: Byungchul Park <byungchul@sk.com>
Reviewed-by: Mina Almasry <almasrymina@google.com>
Reviewed-by: Toke Høiland-Jørgensen <toke@redhat.com>
Reviewed-by: Pavel Begunkov <asml.silence@gmail.com>
Reviewed-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
Link: https://patch.msgid.link/20250702053256.4594-3-byungchul@sk.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-07-07 18:40:09 -07:00
Byungchul Park
61a3324753 page_pool: rename page_pool_return_page() to page_pool_return_netmem()
Now that page_pool_return_page() is for returning netmem, not struct
page, rename it to page_pool_return_netmem() to reflect what it does.

Signed-off-by: Byungchul Park <byungchul@sk.com>
Reviewed-by: Mina Almasry <almasrymina@google.com>
Reviewed-by: Toke Høiland-Jørgensen <toke@redhat.com>
Reviewed-by: Pavel Begunkov <asml.silence@gmail.com>
Reviewed-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
Link: https://patch.msgid.link/20250702053256.4594-2-byungchul@sk.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-07-07 18:40:08 -07:00
Alexander Mikhalitsyn
c679d17d3f
af_unix: enable handing out pidfds for reaped tasks in SCM_PIDFD
Now everything is ready to pass PIDFD_STALE to pidfd_prepare().
This will allow opening pidfd for reaped tasks.

Cc: linux-kernel@vger.kernel.org
Cc: netdev@vger.kernel.org
Cc: David S. Miller <davem@davemloft.net>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Paolo Abeni <pabeni@redhat.com>
Cc: Simon Horman <horms@kernel.org>
Cc: Willem de Bruijn <willemb@google.com>
Cc: Leon Romanovsky <leon@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Kuniyuki Iwashima <kuniyu@google.com>
Cc: Lennart Poettering <mzxreary@0pointer.de>
Cc: Luca Boccassi <bluca@debian.org>
Cc: David Rheinsberg <david@readahead.eu>
Signed-off-by: Alexander Mikhalitsyn <aleksandr.mikhalitsyn@canonical.com>
Link: https://lore.kernel.org/20250703222314.309967-7-aleksandr.mikhalitsyn@canonical.com
Reviewed-by: Christian Brauner <brauner@kernel.org>
Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-07-04 09:32:35 +02:00
Alexander Mikhalitsyn
2775832f71
af_unix: stash pidfs dentry when needed
We need to ensure that pidfs dentry is allocated when we meet any
struct pid for the first time. This will allows us to open pidfd
even after the task it corresponds to is reaped.

Basically, we need to identify all places where we fill skb/scm_cookie
with struct pid reference for the first time and call pidfs_register_pid().

Tricky thing here is that we have a few places where this happends
depending on what userspace is doing:
- [__scm_replace_pid()] explicitly sending an SCM_CREDENTIALS message
                        and specified pid in a numeric format
- [unix_maybe_add_creds()] enabled SO_PASSCRED/SO_PASSPIDFD but
                           didn't send SCM_CREDENTIALS explicitly
- [scm_send()] force_creds is true. Netlink case, we don't need to touch it.

Cc: linux-kernel@vger.kernel.org
Cc: netdev@vger.kernel.org
Cc: David S. Miller <davem@davemloft.net>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Paolo Abeni <pabeni@redhat.com>
Cc: Simon Horman <horms@kernel.org>
Cc: Leon Romanovsky <leon@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Kuniyuki Iwashima <kuniyu@google.com>
Cc: Lennart Poettering <mzxreary@0pointer.de>
Cc: Luca Boccassi <bluca@debian.org>
Cc: David Rheinsberg <david@readahead.eu>
Signed-off-by: Alexander Mikhalitsyn <aleksandr.mikhalitsyn@canonical.com>
Link: https://lore.kernel.org/20250703222314.309967-6-aleksandr.mikhalitsyn@canonical.com
Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-07-04 09:32:35 +02:00
Alexander Mikhalitsyn
30580dc96a
af_unix: introduce and use scm_replace_pid() helper
Existing logic in __scm_send() related to filling an struct scm_cookie
with a proper struct pid reference is already pretty tricky. Let's
simplify it a bit by introducing a new helper. This helper will be
extended in one of the next patches.

Cc: linux-kernel@vger.kernel.org
Cc: netdev@vger.kernel.org
Cc: David S. Miller <davem@davemloft.net>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Paolo Abeni <pabeni@redhat.com>
Cc: Simon Horman <horms@kernel.org>
Cc: Willem de Bruijn <willemb@google.com>
Cc: Leon Romanovsky <leon@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Kuniyuki Iwashima <kuniyu@google.com>
Cc: Lennart Poettering <mzxreary@0pointer.de>
Cc: Luca Boccassi <bluca@debian.org>
Cc: David Rheinsberg <david@readahead.eu>
Signed-off-by: Alexander Mikhalitsyn <aleksandr.mikhalitsyn@canonical.com>
Link: https://lore.kernel.org/20250703222314.309967-4-aleksandr.mikhalitsyn@canonical.com
Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-07-04 09:32:35 +02:00
Willem de Bruijn
d2527ad3a9 net: preserve MSG_ZEROCOPY with forwarding
MSG_ZEROCOPY data must be copied before data is queued to local
sockets, to avoid indefinite timeout until memory release.

This test is performed by skb_orphan_frags_rx, which is called when
looping an egress skb to packet sockets, error queue or ingress path.

To preserve zerocopy for skbs that are looped to ingress but are then
forwarded to an egress device rather than delivered locally, defer
this last check until an skb enters the local IP receive path.

This is analogous to existing behavior of skb_clear_delivery_time.

Signed-off-by: Willem de Bruijn <willemb@google.com>
Link: https://patch.msgid.link/20250630194312.1571410-2-willemdebruijn.kernel@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-07-02 15:07:16 -07:00
Eric Dumazet
88fe14253e net: dst: add four helpers to annotate data-races around dst->dev
dst->dev is read locklessly in many contexts,
and written in dst_dev_put().

Fixing all the races is going to need many changes.

We probably will have to add full RCU protection.

Add three helpers to ease this painful process.

static inline struct net_device *dst_dev(const struct dst_entry *dst)
{
       return READ_ONCE(dst->dev);
}

static inline struct net_device *skb_dst_dev(const struct sk_buff *skb)
{
       return dst_dev(skb_dst(skb));
}

static inline struct net *skb_dst_dev_net(const struct sk_buff *skb)
{
       return dev_net(skb_dst_dev(skb));
}

static inline struct net *skb_dst_dev_net_rcu(const struct sk_buff *skb)
{
       return dev_net_rcu(skb_dst_dev(skb));
}

Fixes: 4a6ce2b6f2 ("net: introduce a new function dst_dev_put()")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com>
Link: https://patch.msgid.link/20250630121934.3399505-7-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-07-02 14:32:30 -07:00
Eric Dumazet
2dce8c52a9 net: dst: annotate data-races around dst->output
dst_dev_put() can overwrite dst->output while other
cpus might read this field (for instance from dst_output())

Add READ_ONCE()/WRITE_ONCE() annotations to suppress
potential issues.

We will likely need RCU protection in the future.

Fixes: 4a6ce2b6f2 ("net: introduce a new function dst_dev_put()")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com>
Link: https://patch.msgid.link/20250630121934.3399505-6-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-07-02 14:32:30 -07:00
Eric Dumazet
f1c5fd3489 net: dst: annotate data-races around dst->input
dst_dev_put() can overwrite dst->input while other
cpus might read this field (for instance from dst_input())

Add READ_ONCE()/WRITE_ONCE() annotations to suppress
potential issues.

We will likely need full RCU protection later.

Fixes: 4a6ce2b6f2 ("net: introduce a new function dst_dev_put()")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com>
Link: https://patch.msgid.link/20250630121934.3399505-5-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-07-02 14:32:29 -07:00
Eric Dumazet
8f2b2282d0 net: dst: annotate data-races around dst->lastuse
(dst_entry)->lastuse is read and written locklessly,
add corresponding annotations.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com>
Link: https://patch.msgid.link/20250630121934.3399505-4-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-07-02 14:32:29 -07:00
Eric Dumazet
8a402bbe54 net: dst: annotate data-races around dst->obsolete
(dst_entry)->obsolete is read locklessly, add corresponding
annotations.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com>
Link: https://patch.msgid.link/20250630121934.3399505-2-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-07-02 14:32:29 -07:00
Eric Dumazet
8308133741 tcp: move tcp_memory_allocated into net_aligned_data
____cacheline_aligned_in_smp attribute only makes sure to align
a field to a cache line. It does not prevent the linker to use
the remaining of the cache line for other variables, causing
potential false sharing.

Move tcp_memory_allocated into a dedicated cache line.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Link: https://patch.msgid.link/20250630093540.3052835-4-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-07-02 14:22:02 -07:00
Eric Dumazet
998642e999 net: move net_cookie into net_aligned_data
Using per-cpu data for net->net_cookie generation is overkill,
because even busy hosts do not create hundreds of netns per second.

Make sure to put net_cookie in a private cache line to avoid
potential false sharing.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Link: https://patch.msgid.link/20250630093540.3052835-3-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-07-02 14:22:02 -07:00
Eric Dumazet
3715b5df09 net: add struct net_aligned_data
This structure will hold networking data that must
consume a full cache line to avoid accidental false sharing.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Link: https://patch.msgid.link/20250630093540.3052835-2-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-07-02 14:22:02 -07:00
RubenKelevra
21deb2d966 net: ieee8021q: fix insufficient table-size assertion
_Static_assert(ARRAY_SIZE(map) != IEEE8021Q_TT_MAX - 1) rejects only a
length of 7 and allows any other mismatch. Replace it with a strict
equality test via a helper macro so that every mapping table must have
exactly IEEE8021Q_TT_MAX (8) entries.

Signed-off-by: RubenKelevra <rubenkelevra@gmail.com>
Link: https://patch.msgid.link/20250626205907.1566384-1-rubenkelevra@gmail.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2025-07-01 12:55:49 +02:00
Eric Dumazet
aed4969f2b net: net->nsid_lock does not need BH safety
At the time of commit bc51dddf98 ("netns: avoid disabling irq
for netns id") peernet2id() was not yet using RCU.

Commit 2dce224f46 ("netns: protect netns
ID lookups with RCU") changed peernet2id() to no longer
acquire net->nsid_lock (potentially from BH context).

We do not need to block soft interrupts when acquiring
net->nsid_lock anymore.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Guillaume Nault <gnault@redhat.com>
Cc: Cong Wang <xiyou.wangcong@gmail.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com>
Link: https://patch.msgid.link/20250627163242.230866-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-06-30 18:58:20 -07:00
Ido Schimmel
03dc03fa04 neighbor: Add NTF_EXT_VALIDATED flag for externally validated entries
tl;dr
=====

Add a new neighbor flag ("extern_valid") that can be used to indicate to
the kernel that a neighbor entry was learned and determined to be valid
externally. The kernel will not try to remove or invalidate such an
entry, leaving these decisions to the user space control plane. This is
needed for EVPN multi-homing where a neighbor entry for a multi-homed
host needs to be synced across all the VTEPs among which the host is
multi-homed.

Background
==========

In a typical EVPN multi-homing setup each host is multi-homed using a
set of links called ES (Ethernet Segment, i.e., LAG) to multiple leaf
switches (VTEPs). VTEPs that are connected to the same ES are called ES
peers.

When a neighbor entry is learned on a VTEP, it is distributed to both ES
peers and remote VTEPs using EVPN MAC/IP advertisement routes. ES peers
use the neighbor entry when routing traffic towards the multi-homed host
and remote VTEPs use it for ARP/NS suppression.

Motivation
==========

If the ES link between a host and the VTEP on which the neighbor entry
was locally learned goes down, the EVPN MAC/IP advertisement route will
be withdrawn and the neighbor entries will be removed from both ES peers
and remote VTEPs. Routing towards the multi-homed host and ARP/NS
suppression can fail until another ES peer locally learns the neighbor
entry and distributes it via an EVPN MAC/IP advertisement route.

"draft-rbickhart-evpn-ip-mac-proxy-adv-03" [1] suggests avoiding these
intermittent failures by having the ES peers install the neighbor
entries as before, but also injecting EVPN MAC/IP advertisement routes
with a proxy indication. When the previously mentioned ES link goes down
and the original EVPN MAC/IP advertisement route is withdrawn, the ES
peers will not withdraw their neighbor entries, but instead start aging
timers for the proxy indication.

If an ES peer locally learns the neighbor entry (i.e., it becomes
"reachable"), it will restart its aging timer for the entry and emit an
EVPN MAC/IP advertisement route without a proxy indication. An ES peer
will stop its aging timer for the proxy indication if it observes the
removal of the proxy indication from at least one of the ES peers
advertising the entry.

In the event that the aging timer for the proxy indication expired, an
ES peer will withdraw its EVPN MAC/IP advertisement route. If the timer
expired on all ES peers and they all withdrew their proxy
advertisements, the neighbor entry will be completely removed from the
EVPN fabric.

Implementation
==============

In the above scheme, when the control plane (e.g., FRR) advertises a
neighbor entry with a proxy indication, it expects the corresponding
entry in the data plane (i.e., the kernel) to remain valid and not be
removed due to garbage collection or loss of carrier. The control plane
also expects the kernel to notify it if the entry was learned locally
(i.e., became "reachable") so that it will remove the proxy indication
from the EVPN MAC/IP advertisement route. That is why these entries
cannot be programmed with dummy states such as "permanent" or "noarp".

Instead, add a new neighbor flag ("extern_valid") which indicates that
the entry was learned and determined to be valid externally and should
not be removed or invalidated by the kernel. The kernel can probe the
entry and notify user space when it becomes "reachable" (it is initially
installed as "stale"). However, if the kernel does not receive a
confirmation, have it return the entry to the "stale" state instead of
the "failed" state.

In other words, an entry marked with the "extern_valid" flag behaves
like any other dynamically learned entry other than the fact that the
kernel cannot remove or invalidate it.

One can argue that the "extern_valid" flag should not prevent garbage
collection and that instead a neighbor entry should be programmed with
both the "extern_valid" and "extern_learn" flags. There are two reasons
for not doing that:

1. Unclear why a control plane would like to program an entry that the
   kernel cannot invalidate but can completely remove.

2. The "extern_learn" flag is used by FRR for neighbor entries learned
   on remote VTEPs (for ARP/NS suppression) whereas here we are
   concerned with local entries. This distinction is currently irrelevant
   for the kernel, but might be relevant in the future.

Given that the flag only makes sense when the neighbor has a valid
state, reject attempts to add a neighbor with an invalid state and with
this flag set. For example:

 # ip neigh add 192.0.2.1 nud none dev br0.10 extern_valid
 Error: Cannot create externally validated neighbor with an invalid state.
 # ip neigh add 192.0.2.1 lladdr 00:11:22:33:44:55 nud stale dev br0.10 extern_valid
 # ip neigh replace 192.0.2.1 nud failed dev br0.10 extern_valid
 Error: Cannot mark neighbor as externally validated with an invalid state.

The above means that a neighbor cannot be created with the
"extern_valid" flag and flags such as "use" or "managed" as they result
in a neighbor being created with an invalid state ("none") and
immediately getting probed:

 # ip neigh add 192.0.2.1 lladdr 00:11:22:33:44:55 nud stale dev br0.10 extern_valid use
 Error: Cannot create externally validated neighbor with an invalid state.

However, these flags can be used together with "extern_valid" after the
neighbor was created with a valid state:

 # ip neigh add 192.0.2.1 lladdr 00:11:22:33:44:55 nud stale dev br0.10 extern_valid
 # ip neigh replace 192.0.2.1 lladdr 00:11:22:33:44:55 nud stale dev br0.10 extern_valid use

One consequence of preventing the kernel from invalidating a neighbor
entry is that by default it will only try to determine reachability
using unicast probes. This can be changed using the "mcast_resolicit"
sysctl:

 # sysctl net.ipv4.neigh.br0/10.mcast_resolicit
 0
 # tcpdump -nn -e -i br0.10 -Q out arp &
 # ip neigh replace 192.0.2.1 lladdr 00:11:22:33:44:55 nud stale dev br0.10 extern_valid use
 62:50:1d:11:93:6f > 00:11:22:33:44:55, ethertype ARP (0x0806), length 42: Request who-has 192.0.2.1 tell 192.0.2.2, length 28
 62:50:1d:11:93:6f > 00:11:22:33:44:55, ethertype ARP (0x0806), length 42: Request who-has 192.0.2.1 tell 192.0.2.2, length 28
 62:50:1d:11:93:6f > 00:11:22:33:44:55, ethertype ARP (0x0806), length 42: Request who-has 192.0.2.1 tell 192.0.2.2, length 28
 # sysctl -wq net.ipv4.neigh.br0/10.mcast_resolicit=3
 # ip neigh replace 192.0.2.1 lladdr 00:11:22:33:44:55 nud stale dev br0.10 extern_valid use
 62:50:1d:11:93:6f > 00:11:22:33:44:55, ethertype ARP (0x0806), length 42: Request who-has 192.0.2.1 tell 192.0.2.2, length 28
 62:50:1d:11:93:6f > 00:11:22:33:44:55, ethertype ARP (0x0806), length 42: Request who-has 192.0.2.1 tell 192.0.2.2, length 28
 62:50:1d:11:93:6f > 00:11:22:33:44:55, ethertype ARP (0x0806), length 42: Request who-has 192.0.2.1 tell 192.0.2.2, length 28
 62:50:1d:11:93:6f > ff:ff:ff:ff:ff:ff, ethertype ARP (0x0806), length 42: Request who-has 192.0.2.1 tell 192.0.2.2, length 28
 62:50:1d:11:93:6f > ff:ff:ff:ff:ff:ff, ethertype ARP (0x0806), length 42: Request who-has 192.0.2.1 tell 192.0.2.2, length 28
 62:50:1d:11:93:6f > ff:ff:ff:ff:ff:ff, ethertype ARP (0x0806), length 42: Request who-has 192.0.2.1 tell 192.0.2.2, length 28

iproute2 patches can be found here [2].

[1] https://datatracker.ietf.org/doc/html/draft-rbickhart-evpn-ip-mac-proxy-adv-03
[2] https://github.com/idosch/iproute2/tree/submit/extern_valid_v1

Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://patch.msgid.link/20250626073111.244534-2-idosch@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-06-30 18:14:23 -07:00
Jakub Kicinski
32155c6fd9 bpf-next-for-netdev
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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 2025-06-27

We've added 6 non-merge commits during the last 8 day(s) which contain
a total of 6 files changed, 120 insertions(+), 20 deletions(-).

The main changes are:

1) Fix RCU usage in task_cls_state() for BPF programs using helpers like
   bpf_get_cgroup_classid_curr() outside of networking, from Charalampos
   Mitrodimas.

2) Fix a sockmap race between map_update and a pending workqueue from
   an earlier map_delete freeing the old psock where both pointed to the
   same psock->sk, from Jiayuan Chen.

3) Fix a data corruption issue when using bpf_msg_pop_data() in kTLS which
   failed to recalculate the ciphertext length, also from Jiayuan Chen.

4) Remove xdp_redirect_map{,_err} trace events since they are unused and
   also hide XDP trace events under CONFIG_BPF_SYSCALL, from Steven Rostedt.

* tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next:
  xdp: tracing: Hide some xdp events under CONFIG_BPF_SYSCALL
  xdp: Remove unused events xdp_redirect_map and xdp_redirect_map_err
  net, bpf: Fix RCU usage in task_cls_state() for BPF programs
  selftests/bpf: Add test to cover ktls with bpf_msg_pop_data
  bpf, ktls: Fix data corruption when using bpf_msg_pop_data() in ktls
  bpf, sockmap: Fix psock incorrectly pointing to sk
====================

Link: https://patch.msgid.link/20250626230111.24772-1-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-06-26 17:13:17 -07:00
Jakub Kicinski
28aa52b618 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Cross-merge networking fixes after downstream PR (net-6.16-rc4).

Conflicts:

Documentation/netlink/specs/mptcp_pm.yaml
  9e6dd4c256 ("netlink: specs: mptcp: replace underscores with dashes in names")
  ec362192aa ("netlink: specs: fix up indentation errors")
https://lore.kernel.org/20250626122205.389c2cd4@canb.auug.org.au

Adjacent changes:

Documentation/netlink/specs/fou.yaml
  791a9ed0a4 ("netlink: specs: fou: replace underscores with dashes in names")
  880d43ca9a ("netlink: specs: clean up spaces in brackets")

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-06-26 10:40:50 -07:00
Jakub Kicinski
8d89661a36 net: selftests: fix TCP packet checksum
The length in the pseudo header should be the length of the L3 payload
AKA the L4 header+payload. The selftest code builds the packet from
the lower layers up, so all the headers are pushed already when it
constructs L4. We need to subtract the lower layer headers from skb->len.

Fixes: 3e1e58d64c ("net: add generic selftest support")
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Reviewed-by: Gerhard Engleder <gerhard@engleder-embedded.com>
Reported-by: Oleksij Rempel <o.rempel@pengutronix.de>
Tested-by: Oleksij Rempel <o.rempel@pengutronix.de>
Reviewed-by: Oleksij Rempel <o.rempel@pengutronix.de>
Link: https://patch.msgid.link/20250624183258.3377740-1-kuba@kernel.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2025-06-26 10:50:49 +02:00
Yue Haibing
f6fa45d67e net: Reoder rxq_idx check in __net_mp_open_rxq()
array_index_nospec() clamp the rxq_idx within the range of
[0, dev->real_num_rx_queues), move the check before it.

Signed-off-by: Yue Haibing <yuehaibing@huawei.com>
Reviewed-by: Mina Almasry <almasrymina@google.com>
Link: https://patch.msgid.link/20250624140159.3929503-1-yuehaibing@huawei.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-06-25 16:53:51 -07:00
Yue Haibing
9b19b50c8d neighbour: Remove redundant assignment to err
'err' has been checked against 0 in the if statement.

Signed-off-by: Yue Haibing <yuehaibing@huawei.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20250624014216.3686659-1-yuehaibing@huawei.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-06-25 15:26:03 -07:00
Eric Dumazet
935b67675a net: make sk->sk_rcvtimeo lockless
Followup of commit 285975dd67 ("net: annotate data-races around
sk->sk_{rcv|snd}timeo").

Remove lock_sock()/release_sock() from ksmbd_tcp_rcv_timeout()
and add READ_ONCE()/WRITE_ONCE() where it is needed.

Also SO_RCVTIMEO_OLD and SO_RCVTIMEO_NEW can call sock_set_timeout()
without holding the socket lock.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20250620155536.335520-3-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-06-23 17:05:12 -07:00
Eric Dumazet
3169e36ae1 net: make sk->sk_sndtimeo lockless
Followup of commit 285975dd67 ("net: annotate data-races around
sk->sk_{rcv|snd}timeo").

Remove lock_sock()/release_sock() from sock_set_sndtimeo(),
and add READ_ONCE()/WRITE_ONCE() where it is needed.

Also SO_SNDTIMEO_OLD and SO_SNDTIMEO_NEW can call sock_set_timeout()
without holding the socket lock.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20250620155536.335520-2-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-06-23 17:05:11 -07:00
Eric Dumazet
c51da3f7a1 net: remove sock_i_uid()
Difference between sock_i_uid() and sk_uid() is that
after sock_orphan(), sock_i_uid() returns GLOBAL_ROOT_UID
while sk_uid() returns the last cached sk->sk_uid value.

None of sock_i_uid() callers care about this.

Use sk_uid() which is much faster and inlined.

Note that diag/dump users are calling sock_i_ino() and
can not see the full benefit yet.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Lorenzo Colitti <lorenzo@google.com>
Reviewed-by: Maciej Żenczykowski <maze@google.com>
Link: https://patch.msgid.link/20250620133001.4090592-3-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-06-23 17:04:03 -07:00
Breno Leitao
f599020702 net: netpoll: Initialize UDP checksum field before checksumming
commit f1fce08e63 ("netpoll: Eliminate redundant assignment") removed
the initialization of the UDP checksum, which was wrong and broke
netpoll IPv6 transmission due to bad checksumming.

udph->check needs to be set before calling csum_ipv6_magic().

Fixes: f1fce08e63 ("netpoll: Eliminate redundant assignment")
Signed-off-by: Breno Leitao <leitao@debian.org>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20250620-netpoll_fix-v1-1-f9f0b82bc059@debian.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-06-23 13:14:51 -07:00
Jakub Kicinski
77f08133bc Merge branch 'ref_tracker-add-ability-to-register-a-debugfs-file-for-a-ref_tracker_dir'
Jeff Layton says:

====================
ref_tracker: add ability to register a debugfs file for a ref_tracker_dir

For those just joining in, this series adds a new top-level
"ref_tracker" debugfs directory, and has each ref_tracker_dir register a
file in there as part of its initialization. It also adds the ability to
register a symlink with a more human-usable name that points to the
file, and does some general cleanup of how the ref_tracker object names
are handled.

v14: https://lore.kernel.org/20250610-reftrack-dbgfs-v14-0-efb532861428@kernel.org
v13: https://lore.kernel.org/20250603-reftrack-dbgfs-v13-0-7b2a425019d8@kernel.org
v12: https://lore.kernel.org/20250529-reftrack-dbgfs-v12-0-11b93c0c0b6e@kernel.org
v11: https://lore.kernel.org/20250528-reftrack-dbgfs-v11-0-94ae0b165841@kernel.org
v10: https://lore.kernel.org/20250527-reftrack-dbgfs-v10-0-dc55f7705691@kernel.org
v9: https://lore.kernel.org/20250509-reftrack-dbgfs-v9-0-8ab888a4524d@kernel.org
v8: https://lore.kernel.org/20250507-reftrack-dbgfs-v8-0-607717d3bb98@kernel.org
v7: https://lore.kernel.org/20250505-reftrack-dbgfs-v7-0-f78c5d97bcca@kernel.org
v6: https://lore.kernel.org/20250430-reftrack-dbgfs-v6-0-867c29aff03a@kernel.org
v5: https://lore.kernel.org/20250428-reftrack-dbgfs-v5-0-1cbbdf2038bd@kernel.org
v4: https://lore.kernel.org/20250418-reftrack-dbgfs-v4-0-5ca5c7899544@kernel.org
v3: https://lore.kernel.org/20250417-reftrack-dbgfs-v3-0-c3159428c8fb@kernel.org
v2: https://lore.kernel.org/20250415-reftrack-dbgfs-v2-0-b18c4abd122f@kernel.org
v1: https://lore.kernel.org/20250414-reftrack-dbgfs-v1-0-f03585832203@kernel.org
====================

Link: https://patch.msgid.link/20250618-reftrack-dbgfs-v15-0-24fc37ead144@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-06-19 17:02:07 -07:00
Jeff Layton
707bd05be7 ref_tracker: eliminate the ref_tracker_dir name field
Now that we have dentries and the ability to create meaningful symlinks
to them, don't keep a name string in each tracker. Switch the output
format to print "class@address", and drop the name field.

Also, add a kerneldoc header for ref_tracker_dir_init().

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Link: https://patch.msgid.link/20250618-reftrack-dbgfs-v15-9-24fc37ead144@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-06-19 17:02:04 -07:00
Jeff Layton
8f2079f8da net: add symlinks to ref_tracker_dir for netns
After assigning the inode number to the namespace, use it to create a
unique name for each netns refcount tracker with the ns.inum and
net_cookie values in it, and register a symlink to the debugfs file for
it.

init_net is registered before the ref_tracker dir is created, so add a
late_initcall() to register its files and symlinks.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Link: https://patch.msgid.link/20250618-reftrack-dbgfs-v15-8-24fc37ead144@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-06-19 17:02:04 -07:00
Jeff Layton
aa7d26c3c3 ref_tracker: add a static classname string to each ref_tracker_dir
A later patch in the series will be adding debugfs files for each
ref_tracker that get created in ref_tracker_dir_init(). The format will
be "class@%px". The current "name" string can vary between
ref_tracker_dir objects of the same type, so it's not suitable for this
purpose.

Add a new "class" string to the ref_tracker dir that describes the
the type of object (sans any individual info for that object).

Also, in the i915 driver, gate the creation of debugfs files on whether
the dentry pointer is still set to NULL. CI has shown that the
ref_tracker_dir can be initialized more than once.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Link: https://patch.msgid.link/20250618-reftrack-dbgfs-v15-4-24fc37ead144@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-06-19 17:02:04 -07:00
Breno Leitao
6ad7969a36 netpoll: Extract IPv6 address retrieval function
Extract the IPv6 address retrieval logic from netpoll_setup() into
a dedicated helper function netpoll_take_ipv6() to improve code
organization and readability.

The function handles obtaining the local IPv6 address from the
network device, including proper address type matching between
local and remote addresses (link-local vs global), and includes
appropriate error handling when IPv6 is not supported or no
suitable address is available.

Signed-off-by: Breno Leitao <leitao@debian.org>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20250618-netpoll_ip_ref-v1-3-c2ac00fe558f@debian.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-06-19 16:15:35 -07:00
Breno Leitao
3699f992e8 netpoll: extract IPv4 address retrieval into helper function
Move the IPv4 address retrieval logic from netpoll_setup() into a
separate netpoll_take_ipv4() function to improve code organization
and readability. This change consolidates the IPv4-specific logic
and error handling into a dedicated function while maintaining
the same functionality.

No functional changes.

Signed-off-by: Breno Leitao <leitao@debian.org>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20250618-netpoll_ip_ref-v1-2-c2ac00fe558f@debian.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-06-19 16:15:35 -07:00
Breno Leitao
76d30b51e8 netpoll: Extract carrier wait function
Extract the carrier waiting logic into a dedicated helper function
netpoll_wait_carrier() to improve code readability and reduce
duplication in netpoll_setup().

Signed-off-by: Breno Leitao <leitao@debian.org>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20250618-netpoll_ip_ref-v1-1-c2ac00fe558f@debian.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-06-19 16:15:35 -07:00
Nicolas Escande
c7d78566bb neighbour: add support for NUD_PERMANENT proxy entries
As discussesd before in [0] proxy entries (which are more configuration
than runtime data) should stay when the link (carrier) goes does down.
This is what happens for regular neighbour entries.

So lets fix this by:
  - storing in proxy entries the fact that it was added as NUD_PERMANENT
  - not removing NUD_PERMANENT proxy entries when the carrier goes down
    (same as how it's done in neigh_flush_dev() for regular neigh entries)

[0]: https://lore.kernel.org/netdev/c584ef7e-6897-01f3-5b80-12b53f7b4bf4@kernel.org/

Signed-off-by: Nicolas Escande <nico.escande@gmail.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com>
Link: https://patch.msgid.link/20250617141334.3724863-1-nico.escande@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-06-19 16:15:34 -07:00
Jakub Kicinski
62deb67fc5 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Cross-merge networking fixes after downstream PR (net-6.16-rc3).

No conflicts or adjacent changes.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-06-19 13:00:24 -07:00
Stanislav Fomichev
3a321b6b1f net: remove redundant ASSERT_RTNL() in queue setup functions
The existing netdev_ops_assert_locked() already asserts that either
the RTNL lock or the per-device lock is held, making the explicit
ASSERT_RTNL() redundant.

Cc: Michael Chan <michael.chan@broadcom.com>
Signed-off-by: Stanislav Fomichev <stfomichev@gmail.com>
Link: https://patch.msgid.link/20250616162117.287806-5-stfomichev@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-06-18 18:53:51 -07:00
Stanislav Fomichev
1ead750109 udp_tunnel: remove rtnl_lock dependency
Drivers that are using ops lock and don't depend on RTNL lock
still need to manage it because udp_tunnel's RTNL dependency.
Introduce new udp_tunnel_nic_lock and use it instead of
rtnl_lock. Drop non-UDP_TUNNEL_NIC_INFO_MAY_SLEEP mode from
udp_tunnel infra (udp_tunnel_nic_device_sync_work needs to
grab udp_tunnel_nic_lock mutex and might sleep).

Cover more places in v4:

- netlink
  - udp_tunnel_notify_add_rx_port (ndo_open)
    - triggers udp_tunnel_nic_device_sync_work
  - udp_tunnel_notify_del_rx_port (ndo_stop)
    - triggers udp_tunnel_nic_device_sync_work
  - udp_tunnel_get_rx_info (__netdev_update_features)
    - triggers NETDEV_UDP_TUNNEL_PUSH_INFO
  - udp_tunnel_drop_rx_info (__netdev_update_features)
    - triggers NETDEV_UDP_TUNNEL_DROP_INFO
  - udp_tunnel_nic_reset_ntf (ndo_open)

- notifiers
  - udp_tunnel_nic_netdevice_event, depending on the event:
    - triggers NETDEV_UDP_TUNNEL_PUSH_INFO
    - triggers NETDEV_UDP_TUNNEL_DROP_INFO

- ethnl_tunnel_info_reply_size
- udp_tunnel_nic_set_port_priv (two intel drivers)

Cc: Michael Chan <michael.chan@broadcom.com>
Suggested-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Stanislav Fomichev <stfomichev@gmail.com>
Link: https://patch.msgid.link/20250616162117.287806-4-stfomichev@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-06-18 18:53:51 -07:00
Mina Almasry
6f793a1d05 net: netmem: fix skb_ensure_writable with unreadable skbs
skb_ensure_writable should succeed when it's trying to write to the
header of the unreadable skbs, so it doesn't need an unconditional
skb_frags_readable check. The preceding pskb_may_pull() call will
succeed if write_len is within the head and fail if we're trying to
write to the unreadable payload, so we don't need an additional check.

Removing this check restores DSCP functionality with unreadable skbs as
it's called from dscp_tg.

Cc: willemb@google.com
Cc: asml.silence@gmail.com
Fixes: 65249feb6b ("net: add support for skbs with unreadable frags")
Signed-off-by: Mina Almasry <almasrymina@google.com>
Acked-by: Stanislav Fomichev <sdf@fomichev.me>
Link: https://patch.msgid.link/20250615200733.520113-1-almasrymina@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-06-17 15:48:20 -07:00
Breno Leitao
ccc7edf0ad netpoll: move netpoll_print_options to netconsole
Move netpoll_print_options() from net/core/netpoll.c to
drivers/net/netconsole.c and make it static. This function is only used
by netconsole, so there's no need to export it or keep it in the public
netpoll API.

This reduces the netpoll API surface and improves code locality
by keeping netconsole-specific functionality within the netconsole
driver.

Signed-off-by: Breno Leitao <leitao@debian.org>
Link: https://patch.msgid.link/20250613-rework-v3-4-0752bf2e6912@debian.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-06-16 15:18:33 -07:00
Breno Leitao
5a34c9a853 netpoll: relocate netconsole-specific functions to netconsole module
Move netpoll_parse_ip_addr() and netpoll_parse_options() from the generic
netpoll module to the netconsole module where they are actually used.

These functions were originally placed in netpoll but are only consumed by
netconsole. This refactoring improves code organization by:

 - Removing unnecessary exported symbols from netpoll
 - Making netpoll_parse_options() static (no longer needs global visibility)
 - Reducing coupling between netpoll and netconsole modules

The functions remain functionally identical - this is purely a code
reorganization to better reflect their actual usage patterns. Here are
the changes:

 1) Move both functions from netpoll to netconsole
 2) Add static to netpoll_parse_options()
 3) Removed the EXPORT_SYMBOL()

PS: This diff does not change the function format, so, it is easy to
review, but, checkpatch will not be happy. A follow-up patch will
address the current issues reported by checkpatch.

Signed-off-by: Breno Leitao <leitao@debian.org>
Link: https://patch.msgid.link/20250613-rework-v3-3-0752bf2e6912@debian.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-06-16 15:18:33 -07:00
Breno Leitao
afb023329c netpoll: expose netpoll logging macros in public header
Move np_info(), np_err(), and np_notice() macros from internal
implementation to the public netpoll header file to make them
available for use by netpoll consumers.

These logging macros provide consistent formatting for netpoll-related
messages by automatically prefixing log output with the netpoll instance
name.

The goal is to use the exact same format that is being displayed today,
instead of creating something netconsole-specific.

Signed-off-by: Breno Leitao <leitao@debian.org>
Link: https://patch.msgid.link/20250613-rework-v3-2-0752bf2e6912@debian.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-06-16 15:18:33 -07:00
Breno Leitao
260948993a netpoll: remove __netpoll_cleanup from exported API
Since commit 97714695ef ("net: netconsole: Defer netpoll cleanup to
avoid lock release during list traversal"), netconsole no longer uses
__netpoll_cleanup(). With no remaining users, remove this function
from the exported netpoll API.

The function remains available internally within netpoll for use by
netpoll_cleanup().

Signed-off-by: Breno Leitao <leitao@debian.org>
Link: https://patch.msgid.link/20250613-rework-v3-1-0752bf2e6912@debian.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-06-16 15:18:33 -07:00
Yajun Deng
0c17270f9b net: sysfs: Implement is_visible for phys_(port_id, port_name, switch_id)
phys_port_id_show, phys_port_name_show and phys_switch_id_show would
return -EOPNOTSUPP if the netdev didn't implement the corresponding
method.

There is no point in creating these files if they are unsupported.

Put these attributes in netdev_phys_group and implement the is_visible
method. make phys_(port_id, port_name, switch_id) invisible if the netdev
dosen't implement the corresponding method.

Signed-off-by: Yajun Deng <yajun.deng@linux.dev>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20250612142707.4644-1-yajun.deng@linux.dev
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-06-14 11:26:59 -07:00
Jakub Kicinski
535de52801 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Cross-merge networking fixes after downstream PR (net-6.16-rc2).

No conflicts or adjacent changes.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-06-12 10:09:10 -07:00
Linus Torvalds
27605c8c0f Including fixes from bluetooth and wireless.
Current release - regressions:
 
  - af_unix: allow passing cred for embryo without SO_PASSCRED/SO_PASSPIDFD
 
 Current release - new code bugs:
 
  - eth: airoha: correct enable mask for RX queues 16-31
 
  - veth: prevent NULL pointer dereference in veth_xdp_rcv when peer
    disappears under traffic
 
  - ipv6: move fib6_config_validate() to ip6_route_add(), prevent invalid
    routes
 
 Previous releases - regressions:
 
  - phy: phy_caps: don't skip better duplex match on non-exact match
 
  - dsa: b53: fix untagged traffic sent via cpu tagged with VID 0
 
  - Revert "wifi: mwifiex: Fix HT40 bandwidth issue.", it caused transient
    packet loss, exact reason not fully understood, yet
 
 Previous releases - always broken:
 
  - net: clear the dst when BPF is changing skb protocol (IPv4 <> IPv6)
 
  - sched: sfq: fix a potential crash on gso_skb handling
 
  - Bluetooth: intel: improve rx buffer posting to avoid causing issues
    in the firmware
 
  - eth: intel: i40e: make reset handling robust against multiple requests
 
  - eth: mlx5: ensure FW pages are always allocated on the local NUMA
    node, even when device is configure to 'serve' another node
 
  - wifi: ath12k: fix GCC_GCC_PCIE_HOT_RST definition for WCN7850,
    prevent kernel crashes
 
  - wifi: ath11k: avoid burning CPU in ath11k_debugfs_fw_stats_request()
    for 3 sec if fw_stats_done is not set
 
 Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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Merge tag 'net-6.16-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net

Pull networking fixes from Jakub Kicinski:
 "Including fixes from bluetooth and wireless.

  Current release - regressions:

   - af_unix: allow passing cred for embryo without SO_PASSCRED/SO_PASSPIDFD

  Current release - new code bugs:

   - eth: airoha: correct enable mask for RX queues 16-31

   - veth: prevent NULL pointer dereference in veth_xdp_rcv when peer
     disappears under traffic

   - ipv6: move fib6_config_validate() to ip6_route_add(), prevent
     invalid routes

  Previous releases - regressions:

   - phy: phy_caps: don't skip better duplex match on non-exact match

   - dsa: b53: fix untagged traffic sent via cpu tagged with VID 0

   - Revert "wifi: mwifiex: Fix HT40 bandwidth issue.", it caused
     transient packet loss, exact reason not fully understood, yet

  Previous releases - always broken:

   - net: clear the dst when BPF is changing skb protocol (IPv4 <> IPv6)

   - sched: sfq: fix a potential crash on gso_skb handling

   - Bluetooth: intel: improve rx buffer posting to avoid causing issues
     in the firmware

   - eth: intel: i40e: make reset handling robust against multiple
     requests

   - eth: mlx5: ensure FW pages are always allocated on the local NUMA
     node, even when device is configure to 'serve' another node

   - wifi: ath12k: fix GCC_GCC_PCIE_HOT_RST definition for WCN7850,
     prevent kernel crashes

   - wifi: ath11k: avoid burning CPU in ath11k_debugfs_fw_stats_request()
     for 3 sec if fw_stats_done is not set"

* tag 'net-6.16-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (70 commits)
  selftests: drv-net: rss_ctx: Add test for ntuple rules targeting default RSS context
  net: ethtool: Don't check if RSS context exists in case of context 0
  af_unix: Allow passing cred for embryo without SO_PASSCRED/SO_PASSPIDFD.
  ipv6: Move fib6_config_validate() to ip6_route_add().
  net: drv: netdevsim: don't napi_complete() from netpoll
  net/mlx5: HWS, Add error checking to hws_bwc_rule_complex_hash_node_get()
  veth: prevent NULL pointer dereference in veth_xdp_rcv
  net_sched: remove qdisc_tree_flush_backlog()
  net_sched: ets: fix a race in ets_qdisc_change()
  net_sched: tbf: fix a race in tbf_change()
  net_sched: red: fix a race in __red_change()
  net_sched: prio: fix a race in prio_tune()
  net_sched: sch_sfq: reject invalid perturb period
  net: phy: phy_caps: Don't skip better duplex macth on non-exact match
  MAINTAINERS: Update Kuniyuki Iwashima's email address.
  selftests: net: add test case for NAT46 looping back dst
  net: clear the dst when changing skb protocol
  net/mlx5e: Fix number of lanes to UNKNOWN when using data_rate_oper
  net/mlx5e: Fix leak of Geneve TLV option object
  net/mlx5: HWS, make sure the uplink is the last destination
  ...
2025-06-12 09:50:36 -07:00
Jakub Kicinski
ba9db6f907 net: clear the dst when changing skb protocol
A not-so-careful NAT46 BPF program can crash the kernel
if it indiscriminately flips ingress packets from v4 to v6:

  BUG: kernel NULL pointer dereference, address: 0000000000000000
    ip6_rcv_core (net/ipv6/ip6_input.c:190:20)
    ipv6_rcv (net/ipv6/ip6_input.c:306:8)
    process_backlog (net/core/dev.c:6186:4)
    napi_poll (net/core/dev.c:6906:9)
    net_rx_action (net/core/dev.c:7028:13)
    do_softirq (kernel/softirq.c:462:3)
    netif_rx (net/core/dev.c:5326:3)
    dev_loopback_xmit (net/core/dev.c:4015:2)
    ip_mc_finish_output (net/ipv4/ip_output.c:363:8)
    NF_HOOK (./include/linux/netfilter.h:314:9)
    ip_mc_output (net/ipv4/ip_output.c:400:5)
    dst_output (./include/net/dst.h:459:9)
    ip_local_out (net/ipv4/ip_output.c:130:9)
    ip_send_skb (net/ipv4/ip_output.c:1496:8)
    udp_send_skb (net/ipv4/udp.c:1040:8)
    udp_sendmsg (net/ipv4/udp.c:1328:10)

The output interface has a 4->6 program attached at ingress.
We try to loop the multicast skb back to the sending socket.
Ingress BPF runs as part of netif_rx(), pushes a valid v6 hdr
and changes skb->protocol to v6. We enter ip6_rcv_core which
tries to use skb_dst(). But the dst is still an IPv4 one left
after IPv4 mcast output.

Clear the dst in all BPF helpers which change the protocol.
Try to preserve metadata dsts, those may carry non-routing
metadata.

Cc: stable@vger.kernel.org
Reviewed-by: Maciej Żenczykowski <maze@google.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Fixes: d219df60a7 ("bpf: Add ipip6 and ip6ip decap support for bpf_skb_adjust_room()")
Fixes: 1b00e0dfe7 ("bpf: update skb->protocol in bpf_skb_net_grow")
Fixes: 6578171a7f ("bpf: add bpf_skb_change_proto helper")
Reviewed-by: Willem de Bruijn <willemb@google.com>
Link: https://patch.msgid.link/20250610001245.1981782-1-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-06-11 17:02:29 -07:00
Charalampos Mitrodimas
7f12c33850 net, bpf: Fix RCU usage in task_cls_state() for BPF programs
The commit ee971630f2 ("bpf: Allow some trace helpers for all prog
types") made bpf_get_cgroup_classid_curr helper available to all BPF
program types, not just networking programs.

This helper calls __task_get_classid() which internally calls
task_cls_state() requiring rcu_read_lock_bh_held(). This works
in networking/tc context where RCU BH is held, but triggers an RCU
warning when called from other contexts like BPF syscall programs
that run under rcu_read_lock_trace():

  WARNING: suspicious RCU usage
  6.15.0-rc4-syzkaller-g079e5c56a5c4 #0 Not tainted
  -----------------------------
  net/core/netclassid_cgroup.c:24 suspicious rcu_dereference_check() usage!

Fix this by also accepting rcu_read_lock_held() and
rcu_read_lock_trace_held() as valid RCU contexts in the
task_cls_state() function. This ensures the helper works correctly
in all needed RCU contexts where it might be called, regular RCU,
RCU BH (for networking), and RCU trace (for BPF syscall programs).

Fixes: ee971630f2 ("bpf: Allow some trace helpers for all prog types")
Reported-by: syzbot+b4169a1cfb945d2ed0ec@syzkaller.appspotmail.com
Signed-off-by: Charalampos Mitrodimas <charmitro@posteo.net>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20250611-rcu-fix-task_cls_state-v3-1-3d30e1de753f@posteo.net
Closes: https://syzkaller.appspot.com/bug?extid=b4169a1cfb945d2ed0ec
2025-06-11 21:30:29 +02:00
Christian Brauner
9b0240b3cc
netns: use stable inode number for initial mount ns
Apart from the network and mount namespace all other namespaces expose a
stable inode number and userspace has been relying on that for a very
long time now. It's very much heavily used API. Align the network
namespace and use a stable inode number from the reserved procfs inode
number space so this is consistent across all namespaces.

Link: https://lore.kernel.org/20250606-work-nsfs-v1-2-b8749c9a8844@kernel.org
Reviewed-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-06-11 11:59:08 +02:00
Samiullah Khawaja
689883de94 net: stop napi kthreads when THREADED napi is disabled
Once the THREADED napi is disabled, the napi kthread should also be
stopped. Keeping the kthread intact after disabling THREADED napi makes
the PID of this kthread show up in the output of netlink 'napi-get' and
ps -ef output.

The is discussed in the patch below:
https://lore.kernel.org/all/20250502191548.559cc416@kernel.org

NAPI kthread should stop only if,

- There are no pending napi poll scheduled for this thread.
- There are no new napi poll scheduled for this thread while it has
  stopped.
- The ____napi_schedule can correctly fallback to the softirq for napi
  polling.

Since napi_schedule_prep provides mutual exclusion over STATE_SCHED bit,
it is safe to unset the STATE_THREADED when SCHED_THREADED is set or the
SCHED bit is not set. SCHED_THREADED being set means that SCHED is
already set and the kthread owns this napi.

To disable threaded napi, unset STATE_THREADED bit safely if
SCHED_THREADED is set or SCHED is unset. Once STATE_THREADED is unset
safely then wait for the kthread to unset the SCHED_THREADED bit so it
safe to stop the kthread.

Add a new test in nl_netdev to verify this behaviour.

Tested:
 ./tools/testing/selftests/net/nl_netdev.py
 TAP version 13
 1..6
 ok 1 nl_netdev.empty_check
 ok 2 nl_netdev.lo_check
 ok 3 nl_netdev.page_pool_check
 ok 4 nl_netdev.napi_list_check
 ok 5 nl_netdev.dev_set_threaded
 ok 6 nl_netdev.nsim_rxq_reset_down
 # Totals: pass:6 fail:0 xfail:0 xpass:0 skip:0 error:0

Ran neper for 300 seconds and did enable/disable of thread napi in a
loop continuously.

Signed-off-by: Samiullah Khawaja <skhawaja@google.com>
Link: https://patch.msgid.link/20250609173015.3851695-1-skhawaja@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-06-10 17:52:03 -07:00
Willem de Bruijn
561939ed44 net: remove unused sock_enable_timestamps
This function was introduced in commit 783da70e83 ("net: add
sock_enable_timestamps"), with one caller in rxrpc.

That only caller was removed in commit 7903d4438b ("rxrpc: Don't use
received skbuff timestamps").

Signed-off-by: Willem de Bruijn <willemb@google.com>
Reviewed-by: Jason Xing <kerneljasonxing@gmail.com>
Link: https://patch.msgid.link/20250609153254.3504909-1-willemdebruijn.kernel@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-06-10 14:43:40 -07:00
Jiayuan Chen
76be5fae32 bpf, sockmap: Fix psock incorrectly pointing to sk
We observed an issue from the latest selftest: sockmap_redir where
sk_psock(psock->sk) != psock in the backlog. The root cause is the special
behavior in sockmap_redir - it frequently performs map_update() and
map_delete() on the same socket. During map_update(), we create a new
psock and during map_delete(), we eventually free the psock via rcu_work
in sk_psock_drop(). However, pending workqueues might still exist and not
be processed yet. If users immediately perform another map_update(), a new
psock will be allocated for the same sk, resulting in two psocks pointing
to the same sk.

When the pending workqueue is later triggered, it uses the old psock to
access sk for I/O operations, which is incorrect.

Timing Diagram:

cpu0                        cpu1

map_update(sk):
    sk->psock = psock1
    psock1->sk = sk
map_delete(sk):
   rcu_work_free(psock1)

map_update(sk):
    sk->psock = psock2
    psock2->sk = sk
                            workqueue:
                                wakeup with psock1, but the sk of psock1
                                doesn't belong to psock1
rcu_handler:
    clean psock1
    free(psock1)

Previously, we used reference counting to address the concurrency issue
between backlog and sock_map_close(). This logic remains necessary as it
prevents the sk from being freed while processing the backlog. But this
patch prevents pending backlogs from using a psock after it has been
stopped.

Note: We cannot call cancel_delayed_work_sync() in map_delete() since this
might be invoked in BPF context by BPF helper, and the function may sleep.

Fixes: 604326b41a ("bpf, sockmap: convert to generic sk_msg interface")
Signed-off-by: Jiayuan Chen <jiayuan.chen@linux.dev>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20250609025908.79331-1-jiayuan.chen@linux.dev
2025-06-10 18:16:15 +02:00
Ingo Molnar
41cb08555c treewide, timers: Rename from_timer() to timer_container_of()
Move this API to the canonical timer_*() namespace.

[ tglx: Redone against pre rc1 ]

Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/all/aB2X0jCKQO56WdMt@gmail.com
2025-06-08 09:07:37 +02:00
Eric Dumazet
feafc73f3e net: prevent a NULL deref in rtnl_create_link()
At the time rtnl_create_link() is running, dev->netdev_ops is NULL,
we must not use netdev_lock_ops() or risk a NULL deref if
CONFIG_NET_SHAPER is defined.

Use netif_set_group() instead of dev_set_group().

 RIP: 0010:netdev_need_ops_lock include/net/netdev_lock.h:33 [inline]
 RIP: 0010:netdev_lock_ops include/net/netdev_lock.h:41 [inline]
 RIP: 0010:dev_set_group+0xc0/0x230 net/core/dev_api.c:82
Call Trace:
 <TASK>
  rtnl_create_link+0x748/0xd10 net/core/rtnetlink.c:3674
  rtnl_newlink_create+0x25c/0xb00 net/core/rtnetlink.c:3813
  __rtnl_newlink net/core/rtnetlink.c:3940 [inline]
  rtnl_newlink+0x16d6/0x1c70 net/core/rtnetlink.c:4055
  rtnetlink_rcv_msg+0x7cf/0xb70 net/core/rtnetlink.c:6944
  netlink_rcv_skb+0x208/0x470 net/netlink/af_netlink.c:2534
  netlink_unicast_kernel net/netlink/af_netlink.c:1313 [inline]
  netlink_unicast+0x75b/0x8d0 net/netlink/af_netlink.c:1339
  netlink_sendmsg+0x805/0xb30 net/netlink/af_netlink.c:1883
  sock_sendmsg_nosec net/socket.c:712 [inline]

Reported-by: syzbot+9fc858ba0312b42b577e@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/netdev/6840265f.a00a0220.d4325.0009.GAE@google.com/T/#u
Signed-off-by: Eric Dumazet <edumazet@google.com>
Fixes: 7e4d784f58 ("net: hold netdev instance lock during rtnetlink operations")
Acked-by: Stanislav Fomichev <sdf@fomichev.me>
Link: https://patch.msgid.link/20250604105815.1516973-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-06-05 08:03:00 -07:00
Eric Dumazet
535caaca92 net: annotate data-races around cleanup_net_task
from_cleanup_net() reads cleanup_net_task locklessly.

Add READ_ONCE()/WRITE_ONCE() annotations to avoid
a potential KCSAN warning, even if the race is harmless.

Fixes: 0734d7c3d9 ("net: expedite synchronize_net() for cleanup_net()")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Jason Xing <kerneljasonxing@gmail.com>
Link: https://patch.msgid.link/20250604093928.1323333-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-06-05 08:02:26 -07:00
Paul Chaignon
ead7f9b8de bpf: Fix L4 csum update on IPv6 in CHECKSUM_COMPLETE
In Cilium, we use bpf_csum_diff + bpf_l4_csum_replace to, among other
things, update the L4 checksum after reverse SNATing IPv6 packets. That
use case is however not currently supported and leads to invalid
skb->csum values in some cases. This patch adds support for IPv6 address
changes in bpf_l4_csum_update via a new flag.

When calling bpf_l4_csum_replace in Cilium, it ends up calling
inet_proto_csum_replace_by_diff:

    1:  void inet_proto_csum_replace_by_diff(__sum16 *sum, struct sk_buff *skb,
    2:                                       __wsum diff, bool pseudohdr)
    3:  {
    4:      if (skb->ip_summed != CHECKSUM_PARTIAL) {
    5:          csum_replace_by_diff(sum, diff);
    6:          if (skb->ip_summed == CHECKSUM_COMPLETE && pseudohdr)
    7:              skb->csum = ~csum_sub(diff, skb->csum);
    8:      } else if (pseudohdr) {
    9:          *sum = ~csum_fold(csum_add(diff, csum_unfold(*sum)));
    10:     }
    11: }

The bug happens when we're in the CHECKSUM_COMPLETE state. We've just
updated one of the IPv6 addresses. The helper now updates the L4 header
checksum on line 5. Next, it updates skb->csum on line 7. It shouldn't.

For an IPv6 packet, the updates of the IPv6 address and of the L4
checksum will cancel each other. The checksums are set such that
computing a checksum over the packet including its checksum will result
in a sum of 0. So the same is true here when we update the L4 checksum
on line 5. We'll update it as to cancel the previous IPv6 address
update. Hence skb->csum should remain untouched in this case.

The same bug doesn't affect IPv4 packets because, in that case, three
fields are updated: the IPv4 address, the IP checksum, and the L4
checksum. The change to the IPv4 address and one of the checksums still
cancel each other in skb->csum, but we're left with one checksum update
and should therefore update skb->csum accordingly. That's exactly what
inet_proto_csum_replace_by_diff does.

This special case for IPv6 L4 checksums is also described atop
inet_proto_csum_replace16, the function we should be using in this case.

This patch introduces a new bpf_l4_csum_replace flag, BPF_F_IPV6,
to indicate that we're updating the L4 checksum of an IPv6 packet. When
the flag is set, inet_proto_csum_replace_by_diff will skip the
skb->csum update.

Fixes: 7d672345ed ("bpf: add generic bpf_csum_diff helper")
Signed-off-by: Paul Chaignon <paul.chaignon@gmail.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://patch.msgid.link/96a6bc3a443e6f0b21ff7b7834000e17fb549e05.1748509484.git.paul.chaignon@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-05-30 19:53:51 -07:00
Paul Chaignon
6043b794c7 net: Fix checksum update for ILA adj-transport
During ILA address translations, the L4 checksums can be handled in
different ways. One of them, adj-transport, consist in parsing the
transport layer and updating any found checksum. This logic relies on
inet_proto_csum_replace_by_diff and produces an incorrect skb->csum when
in state CHECKSUM_COMPLETE.

This bug can be reproduced with a simple ILA to SIR mapping, assuming
packets are received with CHECKSUM_COMPLETE:

  $ ip a show dev eth0
  14: eth0@if15: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default qlen 1000
      link/ether 62:ae:35:9e:0f:8d brd ff:ff:ff:ff:ff:ff link-netnsid 0
      inet6 3333:0:0:1::c078/64 scope global
         valid_lft forever preferred_lft forever
      inet6 fd00:10:244:1::c078/128 scope global nodad
         valid_lft forever preferred_lft forever
      inet6 fe80::60ae:35ff:fe9e:f8d/64 scope link proto kernel_ll
         valid_lft forever preferred_lft forever
  $ ip ila add loc_match fd00:10:244:1 loc 3333:0:0:1 \
      csum-mode adj-transport ident-type luid dev eth0

Then I hit [fd00:10:244:1::c078]:8000 with a server listening only on
[3333:0:0:1::c078]:8000. With the bug, the SYN packet is dropped with
SKB_DROP_REASON_TCP_CSUM after inet_proto_csum_replace_by_diff changed
skb->csum. The translation and drop are visible on pwru [1] traces:

  IFACE   TUPLE                                                        FUNC
  eth0:9  [fd00:10:244:3::3d8]:51420->[fd00:10:244:1::c078]:8000(tcp)  ipv6_rcv
  eth0:9  [fd00:10:244:3::3d8]:51420->[fd00:10:244:1::c078]:8000(tcp)  ip6_rcv_core
  eth0:9  [fd00:10:244:3::3d8]:51420->[fd00:10:244:1::c078]:8000(tcp)  nf_hook_slow
  eth0:9  [fd00:10:244:3::3d8]:51420->[fd00:10:244:1::c078]:8000(tcp)  inet_proto_csum_replace_by_diff
  eth0:9  [fd00:10:244:3::3d8]:51420->[3333:0:0:1::c078]:8000(tcp)     tcp_v6_early_demux
  eth0:9  [fd00:10:244:3::3d8]:51420->[3333:0:0:1::c078]:8000(tcp)     ip6_route_input
  eth0:9  [fd00:10:244:3::3d8]:51420->[3333:0:0:1::c078]:8000(tcp)     ip6_input
  eth0:9  [fd00:10:244:3::3d8]:51420->[3333:0:0:1::c078]:8000(tcp)     ip6_input_finish
  eth0:9  [fd00:10:244:3::3d8]:51420->[3333:0:0:1::c078]:8000(tcp)     ip6_protocol_deliver_rcu
  eth0:9  [fd00:10:244:3::3d8]:51420->[3333:0:0:1::c078]:8000(tcp)     raw6_local_deliver
  eth0:9  [fd00:10:244:3::3d8]:51420->[3333:0:0:1::c078]:8000(tcp)     ipv6_raw_deliver
  eth0:9  [fd00:10:244:3::3d8]:51420->[3333:0:0:1::c078]:8000(tcp)     tcp_v6_rcv
  eth0:9  [fd00:10:244:3::3d8]:51420->[3333:0:0:1::c078]:8000(tcp)     __skb_checksum_complete
  eth0:9  [fd00:10:244:3::3d8]:51420->[3333:0:0:1::c078]:8000(tcp)     kfree_skb_reason(SKB_DROP_REASON_TCP_CSUM)
  eth0:9  [fd00:10:244:3::3d8]:51420->[3333:0:0:1::c078]:8000(tcp)     skb_release_head_state
  eth0:9  [fd00:10:244:3::3d8]:51420->[3333:0:0:1::c078]:8000(tcp)     skb_release_data
  eth0:9  [fd00:10:244:3::3d8]:51420->[3333:0:0:1::c078]:8000(tcp)     skb_free_head
  eth0:9  [fd00:10:244:3::3d8]:51420->[3333:0:0:1::c078]:8000(tcp)     kfree_skbmem

This is happening because inet_proto_csum_replace_by_diff is updating
skb->csum when it shouldn't. The L4 checksum is updated such that it
"cancels" the IPv6 address change in terms of checksum computation, so
the impact on skb->csum is null.

Note this would be different for an IPv4 packet since three fields
would be updated: the IPv4 address, the IP checksum, and the L4
checksum. Two would cancel each other and skb->csum would still need
to be updated to take the L4 checksum change into account.

This patch fixes it by passing an ipv6 flag to
inet_proto_csum_replace_by_diff, to skip the skb->csum update if we're
in the IPv6 case. Note the behavior of the only other user of
inet_proto_csum_replace_by_diff, the BPF subsystem, is left as is in
this patch and fixed in the subsequent patch.

With the fix, using the reproduction from above, I can confirm
skb->csum is not touched by inet_proto_csum_replace_by_diff and the TCP
SYN proceeds to the application after the ILA translation.

Link: https://github.com/cilium/pwru [1]
Fixes: 65d7ab8de5 ("net: Identifier Locator Addressing module")
Signed-off-by: Paul Chaignon <paul.chaignon@gmail.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://patch.msgid.link/b5539869e3550d46068504feb02d37653d939c0b.1748509484.git.paul.chaignon@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-05-30 19:53:51 -07:00
Saurabh Sengar
3ec5233049 hv_netvsc: fix potential deadlock in netvsc_vf_setxdp()
The MANA driver's probe registers netdevice via the following call chain:

mana_probe()
  register_netdev()
    register_netdevice()

register_netdevice() calls notifier callback for netvsc driver,
holding the netdev mutex via netdev_lock_ops().

Further this netvsc notifier callback end up attempting to acquire the
same lock again in dev_xdp_propagate() leading to deadlock.

netvsc_netdev_event()
  netvsc_vf_setxdp()
    dev_xdp_propagate()

This deadlock was not observed so far because net_shaper_ops was never set,
and thus the lock was effectively a no-op in this case. Fix this by using
netif_xdp_propagate() instead of dev_xdp_propagate() to avoid recursive
locking in this path.

And, since no deadlock is observed on the other path which is via
netvsc_probe, add the lock exclusivly for that path.

Also, clean up the unregistration path by removing the unnecessary call to
netvsc_vf_setxdp(), since unregister_netdevice_many_notify() already
performs this cleanup via dev_xdp_uninstall().

Fixes: 97246d6d21 ("net: hold netdev instance lock during ndo_bpf")
Cc: stable@vger.kernel.org
Signed-off-by: Saurabh Sengar <ssengar@linux.microsoft.com>
Tested-by: Erni Sri Satya Vennela <ernis@linux.microsoft.com>
Reviewed-by: Haiyang Zhang <haiyangz@microsoft.com>
Reviewed-by: Subbaraya Sundeep <sbhatta@marvell.com>
Link: https://patch.msgid.link/1748513910-23963-1-git-send-email-ssengar@linux.microsoft.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-05-30 19:31:25 -07:00
Pranjal Shrivastava
c1f4cb8a8d net: Fix net_devmem_bind_dmabuf for non-devmem configs
Fix the signature of the net_devmem_bind_dmabuf API for
CONFIG_NET_DEVMEM=n.

Fixes: bd61848900 ("net: devmem: Implement TX path")
Signed-off-by: Pranjal Shrivastava <praan@google.com>
Link: https://patch.msgid.link/20250528211058.1826608-1-praan@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-05-30 19:23:36 -07:00
Dong Chenchen
271683bb2c page_pool: Fix use-after-free in page_pool_recycle_in_ring
syzbot reported a uaf in page_pool_recycle_in_ring:

BUG: KASAN: slab-use-after-free in lock_release+0x151/0xa30 kernel/locking/lockdep.c:5862
Read of size 8 at addr ffff8880286045a0 by task syz.0.284/6943

CPU: 0 UID: 0 PID: 6943 Comm: syz.0.284 Not tainted 6.13.0-rc3-syzkaller-gdfa94ce54f41 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:378 [inline]
 print_report+0x169/0x550 mm/kasan/report.c:489
 kasan_report+0x143/0x180 mm/kasan/report.c:602
 lock_release+0x151/0xa30 kernel/locking/lockdep.c:5862
 __raw_spin_unlock_bh include/linux/spinlock_api_smp.h:165 [inline]
 _raw_spin_unlock_bh+0x1b/0x40 kernel/locking/spinlock.c:210
 spin_unlock_bh include/linux/spinlock.h:396 [inline]
 ptr_ring_produce_bh include/linux/ptr_ring.h:164 [inline]
 page_pool_recycle_in_ring net/core/page_pool.c:707 [inline]
 page_pool_put_unrefed_netmem+0x748/0xb00 net/core/page_pool.c:826
 page_pool_put_netmem include/net/page_pool/helpers.h:323 [inline]
 page_pool_put_full_netmem include/net/page_pool/helpers.h:353 [inline]
 napi_pp_put_page+0x149/0x2b0 net/core/skbuff.c:1036
 skb_pp_recycle net/core/skbuff.c:1047 [inline]
 skb_free_head net/core/skbuff.c:1094 [inline]
 skb_release_data+0x6c4/0x8a0 net/core/skbuff.c:1125
 skb_release_all net/core/skbuff.c:1190 [inline]
 __kfree_skb net/core/skbuff.c:1204 [inline]
 sk_skb_reason_drop+0x1c9/0x380 net/core/skbuff.c:1242
 kfree_skb_reason include/linux/skbuff.h:1263 [inline]
 __skb_queue_purge_reason include/linux/skbuff.h:3343 [inline]

root cause is:

page_pool_recycle_in_ring
  ptr_ring_produce
    spin_lock(&r->producer_lock);
    WRITE_ONCE(r->queue[r->producer++], ptr)
      //recycle last page to pool
				page_pool_release
				  page_pool_scrub
				    page_pool_empty_ring
				      ptr_ring_consume
				      page_pool_return_page  //release all page
				  __page_pool_destroy
				     free_percpu(pool->recycle_stats);
				     free(pool) //free

     spin_unlock(&r->producer_lock); //pool->ring uaf read
  recycle_stat_inc(pool, ring);

page_pool can be free while page pool recycle the last page in ring.
Add producer-lock barrier to page_pool_release to prevent the page
pool from being free before all pages have been recycled.

recycle_stat_inc() is empty when CONFIG_PAGE_POOL_STATS is not
enabled, which will trigger Wempty-body build warning. Add definition
for pool stat macro to fix warning.

Suggested-by: Jakub Kicinski <kuba@kernel.org>
Link: https://lore.kernel.org/netdev/20250513083123.3514193-1-dongchenchen2@huawei.com
Fixes: ff7d6b27f8 ("page_pool: refurbish version of page_pool code")
Reported-by: syzbot+204a4382fcb3311f3858@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=204a4382fcb3311f3858
Signed-off-by: Dong Chenchen <dongchenchen2@huawei.com>
Reviewed-by: Toke Høiland-Jørgensen <toke@redhat.com>
Reviewed-by: Mina Almasry <almasrymina@google.com>
Link: https://patch.msgid.link/20250527114152.3119109-1-dongchenchen2@huawei.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-05-28 19:19:36 -07:00
Tengteng Yang
8542d6fac2 Fix sock_exceed_buf_limit not being triggered in __sk_mem_raise_allocated
When a process under memory pressure is not part of any cgroup and
the charged flag is false, trace_sock_exceed_buf_limit was not called
as expected.

This regression was introduced by commit 2def8ff3fd ("sock:
Code cleanup on __sk_mem_raise_allocated()"). The fix changes the
default value of charged to true while preserving existing logic.

Fixes: 2def8ff3fd ("sock: Code cleanup on __sk_mem_raise_allocated()")
Signed-off-by: Abel Wu <wuyun.abel@bytedance.com>
Signed-off-by: Tengteng Yang <yangtengteng@bytedance.com>
Link: https://patch.msgid.link/20250527030419.67693-1-yangtengteng@bytedance.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-05-28 19:07:53 -07:00
Linus Torvalds
90b83efa67 bpf-next-6.16
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Merge tag 'bpf-next-6.16' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next

Pull bpf updates from Alexei Starovoitov:

 - Fix and improve BTF deduplication of identical BTF types (Alan
   Maguire and Andrii Nakryiko)

 - Support up to 12 arguments in BPF trampoline on arm64 (Xu Kuohai and
   Alexis Lothoré)

 - Support load-acquire and store-release instructions in BPF JIT on
   riscv64 (Andrea Parri)

 - Fix uninitialized values in BPF_{CORE,PROBE}_READ macros (Anton
   Protopopov)

 - Streamline allowed helpers across program types (Feng Yang)

 - Support atomic update for hashtab of BPF maps (Hou Tao)

 - Implement json output for BPF helpers (Ihor Solodrai)

 - Several s390 JIT fixes (Ilya Leoshkevich)

 - Various sockmap fixes (Jiayuan Chen)

 - Support mmap of vmlinux BTF data (Lorenz Bauer)

 - Support BPF rbtree traversal and list peeking (Martin KaFai Lau)

 - Tests for sockmap/sockhash redirection (Michal Luczaj)

 - Introduce kfuncs for memory reads into dynptrs (Mykyta Yatsenko)

 - Add support for dma-buf iterators in BPF (T.J. Mercier)

 - The verifier support for __bpf_trap() (Yonghong Song)

* tag 'bpf-next-6.16' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (135 commits)
  bpf, arm64: Remove unused-but-set function and variable.
  selftests/bpf: Add tests with stack ptr register in conditional jmp
  bpf: Do not include stack ptr register in precision backtracking bookkeeping
  selftests/bpf: enable many-args tests for arm64
  bpf, arm64: Support up to 12 function arguments
  bpf: Check rcu_read_lock_trace_held() in bpf_map_lookup_percpu_elem()
  bpf: Avoid __bpf_prog_ret0_warn when jit fails
  bpftool: Add support for custom BTF path in prog load/loadall
  selftests/bpf: Add unit tests with __bpf_trap() kfunc
  bpf: Warn with __bpf_trap() kfunc maybe due to uninitialized variable
  bpf: Remove special_kfunc_set from verifier
  selftests/bpf: Add test for open coded dmabuf_iter
  selftests/bpf: Add test for dmabuf_iter
  bpf: Add open coded dmabuf iterator
  bpf: Add dmabuf iterator
  dma-buf: Rename debugfs symbols
  bpf: Fix error return value in bpf_copy_from_user_dynptr
  libbpf: Use mmap to parse vmlinux BTF from sysfs
  selftests: bpf: Add a test for mmapable vmlinux BTF
  btf: Allow mmap of vmlinux btf
  ...
2025-05-28 15:52:42 -07:00
Linus Torvalds
1b98f357da Networking changes for 6.16.
Core
 ----
 
  - Implement the Device Memory TCP transmit path, allowing zero-copy
    data transmission on top of TCP from e.g. GPU memory to the wire.
 
  - Move all the IPv6 routing tables management outside the RTNL scope,
    under its own lock and RCU. The route control path is now 3x times
    faster.
 
  - Convert queue related netlink ops to instance lock, reducing
    again the scope of the RTNL lock. This improves the control plane
    scalability.
 
  - Refactor the software crc32c implementation, removing unneeded
    abstraction layers and improving significantly the related
    micro-benchmarks.
 
  - Optimize the GRO engine for UDP-tunneled traffic, for a 10%
    performance improvement in related stream tests.
 
  - Cover more per-CPU storage with local nested BH locking; this is a
    prep work to remove the current per-CPU lock in local_bh_disable()
    on PREMPT_RT.
 
  - Introduce and use nlmsg_payload helper, combining buffer bounds
    verification with accessing payload carried by netlink messages.
 
 Netfilter
 ---------
 
  - Rewrite the procfs conntrack table implementation, improving
    considerably the dump performance. A lot of user-space tools
    still use this interface.
 
  - Implement support for wildcard netdevice in netdev basechain
    and flowtables.
 
  - Integrate conntrack information into nft trace infrastructure.
 
  - Export set count and backend name to userspace, for better
    introspection.
 
 BPF
 ---
 
  - BPF qdisc support: BPF-qdisc can be implemented with BPF struct_ops
    programs and can be controlled in similar way to traditional qdiscs
    using the "tc qdisc" command.
 
  - Refactor the UDP socket iterator, addressing long standing issues
    WRT duplicate hits or missed sockets.
 
 Protocols
 ---------
 
  - Improve TCP receive buffer auto-tuning and increase the default
    upper bound for the receive buffer; overall this improves the single
    flow maximum thoughput on 200Gbs link by over 60%.
 
  - Add AFS GSSAPI security class to AF_RXRPC; it provides transport
    security for connections to the AFS fileserver and VL server.
 
  - Improve TCP multipath routing, so that the sources address always
    matches the nexthop device.
 
  - Introduce SO_PASSRIGHTS for AF_UNIX, to allow disabling SCM_RIGHTS,
    and thus preventing DoS caused by passing around problematic FDs.
 
  - Retire DCCP socket. DCCP only receives updates for bugs, and major
    distros disable it by default. Its removal allows for better
    organisation of TCP fields to reduce the number of cache lines hit
    in the fast path.
 
  - Extend TCP drop-reason support to cover PAWS checks.
 
 Driver API
 ----------
 
  - Reorganize PTP ioctl flag support to require an explicit opt-in for
    the drivers, avoiding the problem of drivers not rejecting new
    unsupported flags.
 
  - Converted several device drivers to timestamping APIs.
 
  - Introduce per-PHY ethtool dump helpers, improving the support for
    dump operations targeting PHYs.
 
 Tests and tooling
 -----------------
 
  - Add support for classic netlink in user space C codegen, so that
    ynl-c can now read, create and modify links, routes addresses and
    qdisc layer configuration.
 
  - Add ynl sub-types for binary attributes, allowing ynl-c to output
    known struct instead of raw binary data, clarifying the classic
    netlink output.
 
  - Extend MPTCP selftests to improve the code-coverage.
 
  - Add tests for XDP tail adjustment in AF_XDP.
 
 New hardware / drivers
 ----------------------
 
  - OpenVPN virtual driver: offload OpenVPN data channels processing
    to the kernel-space, increasing the data transfer throughput WRT
    the user-space implementation.
 
  - Renesas glue driver for the gigabit ethernet RZ/V2H(P) SoC.
 
  - Broadcom asp-v3.0 ethernet driver.
 
  - AMD Renoir ethernet device.
 
  - ReakTek MT9888 2.5G ethernet PHY driver.
 
  - Aeonsemi 10G C45 PHYs driver.
 
 Drivers
 -------
 
  - Ethernet high-speed NICs:
    - nVidia/Mellanox (mlx5):
      - refactor the stearing table handling to reduce significantly
        the amount of memory used
      - add support for complex matches in H/W flow steering
      - improve flow streeing error handling
      - convert to netdev instance locking
    - Intel (100G, ice, igb, ixgbe, idpf):
      - ice: add switchdev support for LLDP traffic over VF
      - ixgbe: add firmware manipulation and regions devlink support
      - igb: introduce support for frame transmission premption
      - igb: adds persistent NAPI configuration
      - idpf: introduce RDMA support
      - idpf: add initial PTP support
    - Meta (fbnic):
      - extend hardware stats coverage
      - add devlink dev flash support
    - Broadcom (bnxt):
      - add support for RX-side device memory TCP
    - Wangxun (txgbe):
      - implement support for udp tunnel offload
      - complete PTP and SRIOV support for AML 25G/10G devices
 
  - Ethernet NICs embedded and virtual:
    - Google (gve):
      - add device memory TCP TX support
    - Amazon (ena):
      - support persistent per-NAPI config
    - Airoha:
      - add H/W support for L2 traffic offload
      - add per flow stats for flow offloading
    - RealTek (rtl8211): add support for WoL magic packet
    - Synopsys (stmmac):
      - dwmac-socfpga 1000BaseX support
      - add Loongson-2K3000 support
      - introduce support for hardware-accelerated VLAN stripping
    - Broadcom (bcmgenet):
      - expose more H/W stats
    - Freescale (enetc, dpaa2-eth):
      - enetc: add MAC filter, VLAN filter RSS and loopback support
      - dpaa2-eth: convert to H/W timestamping APIs
    - vxlan: convert FDB table to rhashtable, for better scalabilty
    - veth: apply qdisc backpressure on full ring to reduce TX drops
 
  - Ethernet switches:
    - Microchip (kzZ88x3): add ETS scheduler support
 
  - Ethernet PHYs:
    - RealTek (rtl8211):
      - add support for WoL magic packet
      - add support for PHY LEDs
 
  - CAN:
    - Adds RZ/G3E CANFD support to the rcar_canfd driver.
    - Preparatory work for CAN-XL support.
    - Add self-tests framework with support for CAN physical interfaces.
 
  - WiFi:
    - mac80211:
      - scan improvements with multi-link operation (MLO)
    - Qualcomm (ath12k):
      - enable AHB support for IPQ5332
      - add monitor interface support to QCN9274
      - add multi-link operation support to WCN7850
      - add 802.11d scan offload support to WCN7850
      - monitor mode for WCN7850, better 6 GHz regulatory
    - Qualcomm (ath11k):
      - restore hibernation support
    - MediaTek (mt76):
      - WiFi-7 improvements
      - implement support for mt7990
    - Intel (iwlwifi):
      - enhanced multi-link single-radio (EMLSR) support on 5 GHz links
      - rework device configuration
    - RealTek (rtw88):
      - improve throughput for RTL8814AU
    - RealTek (rtw89):
      - add multi-link operation support
      - STA/P2P concurrency improvements
      - support different SAR configs by antenna
 
  - Bluetooth:
    - introduce HCI Driver protocol
    - btintel_pcie: do not generate coredump for diagnostic events
    - btusb: add HCI Drv commands for configuring altsetting
    - btusb: add RTL8851BE device 0x0bda:0xb850
    - btusb: add new VID/PID 13d3/3584 for MT7922
    - btusb: add new VID/PID 13d3/3630 and 13d3/3613 for MT7925
    - btnxpuart: implement host-wakeup feature
 
 Signed-off-by: Paolo Abeni <pabeni@redhat.com>
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Merge tag 'net-next-6.16' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next

Pull networking updates from Paolo Abeni:
 "Core:

   - Implement the Device Memory TCP transmit path, allowing zero-copy
     data transmission on top of TCP from e.g. GPU memory to the wire.

   - Move all the IPv6 routing tables management outside the RTNL scope,
     under its own lock and RCU. The route control path is now 3x times
     faster.

   - Convert queue related netlink ops to instance lock, reducing again
     the scope of the RTNL lock. This improves the control plane
     scalability.

   - Refactor the software crc32c implementation, removing unneeded
     abstraction layers and improving significantly the related
     micro-benchmarks.

   - Optimize the GRO engine for UDP-tunneled traffic, for a 10%
     performance improvement in related stream tests.

   - Cover more per-CPU storage with local nested BH locking; this is a
     prep work to remove the current per-CPU lock in local_bh_disable()
     on PREMPT_RT.

   - Introduce and use nlmsg_payload helper, combining buffer bounds
     verification with accessing payload carried by netlink messages.

  Netfilter:

   - Rewrite the procfs conntrack table implementation, improving
     considerably the dump performance. A lot of user-space tools still
     use this interface.

   - Implement support for wildcard netdevice in netdev basechain and
     flowtables.

   - Integrate conntrack information into nft trace infrastructure.

   - Export set count and backend name to userspace, for better
     introspection.

  BPF:

   - BPF qdisc support: BPF-qdisc can be implemented with BPF struct_ops
     programs and can be controlled in similar way to traditional qdiscs
     using the "tc qdisc" command.

   - Refactor the UDP socket iterator, addressing long standing issues
     WRT duplicate hits or missed sockets.

  Protocols:

   - Improve TCP receive buffer auto-tuning and increase the default
     upper bound for the receive buffer; overall this improves the
     single flow maximum thoughput on 200Gbs link by over 60%.

   - Add AFS GSSAPI security class to AF_RXRPC; it provides transport
     security for connections to the AFS fileserver and VL server.

   - Improve TCP multipath routing, so that the sources address always
     matches the nexthop device.

   - Introduce SO_PASSRIGHTS for AF_UNIX, to allow disabling SCM_RIGHTS,
     and thus preventing DoS caused by passing around problematic FDs.

   - Retire DCCP socket. DCCP only receives updates for bugs, and major
     distros disable it by default. Its removal allows for better
     organisation of TCP fields to reduce the number of cache lines hit
     in the fast path.

   - Extend TCP drop-reason support to cover PAWS checks.

  Driver API:

   - Reorganize PTP ioctl flag support to require an explicit opt-in for
     the drivers, avoiding the problem of drivers not rejecting new
     unsupported flags.

   - Converted several device drivers to timestamping APIs.

   - Introduce per-PHY ethtool dump helpers, improving the support for
     dump operations targeting PHYs.

  Tests and tooling:

   - Add support for classic netlink in user space C codegen, so that
     ynl-c can now read, create and modify links, routes addresses and
     qdisc layer configuration.

   - Add ynl sub-types for binary attributes, allowing ynl-c to output
     known struct instead of raw binary data, clarifying the classic
     netlink output.

   - Extend MPTCP selftests to improve the code-coverage.

   - Add tests for XDP tail adjustment in AF_XDP.

  New hardware / drivers:

   - OpenVPN virtual driver: offload OpenVPN data channels processing to
     the kernel-space, increasing the data transfer throughput WRT the
     user-space implementation.

   - Renesas glue driver for the gigabit ethernet RZ/V2H(P) SoC.

   - Broadcom asp-v3.0 ethernet driver.

   - AMD Renoir ethernet device.

   - ReakTek MT9888 2.5G ethernet PHY driver.

   - Aeonsemi 10G C45 PHYs driver.

  Drivers:

   - Ethernet high-speed NICs:
       - nVidia/Mellanox (mlx5):
           - refactor the steering table handling to significantly
             reduce the amount of memory used
           - add support for complex matches in H/W flow steering
           - improve flow streeing error handling
           - convert to netdev instance locking
       - Intel (100G, ice, igb, ixgbe, idpf):
           - ice: add switchdev support for LLDP traffic over VF
           - ixgbe: add firmware manipulation and regions devlink support
           - igb: introduce support for frame transmission premption
           - igb: adds persistent NAPI configuration
           - idpf: introduce RDMA support
           - idpf: add initial PTP support
       - Meta (fbnic):
           - extend hardware stats coverage
           - add devlink dev flash support
       - Broadcom (bnxt):
           - add support for RX-side device memory TCP
       - Wangxun (txgbe):
           - implement support for udp tunnel offload
           - complete PTP and SRIOV support for AML 25G/10G devices

   - Ethernet NICs embedded and virtual:
       - Google (gve):
           - add device memory TCP TX support
       - Amazon (ena):
           - support persistent per-NAPI config
       - Airoha:
           - add H/W support for L2 traffic offload
           - add per flow stats for flow offloading
       - RealTek (rtl8211): add support for WoL magic packet
       - Synopsys (stmmac):
           - dwmac-socfpga 1000BaseX support
           - add Loongson-2K3000 support
           - introduce support for hardware-accelerated VLAN stripping
       - Broadcom (bcmgenet):
           - expose more H/W stats
       - Freescale (enetc, dpaa2-eth):
           - enetc: add MAC filter, VLAN filter RSS and loopback support
           - dpaa2-eth: convert to H/W timestamping APIs
       - vxlan: convert FDB table to rhashtable, for better scalabilty
       - veth: apply qdisc backpressure on full ring to reduce TX drops

   - Ethernet switches:
       - Microchip (kzZ88x3): add ETS scheduler support

   - Ethernet PHYs:
       - RealTek (rtl8211):
           - add support for WoL magic packet
           - add support for PHY LEDs

   - CAN:
       - Adds RZ/G3E CANFD support to the rcar_canfd driver.
       - Preparatory work for CAN-XL support.
       - Add self-tests framework with support for CAN physical interfaces.

   - WiFi:
       - mac80211:
           - scan improvements with multi-link operation (MLO)
       - Qualcomm (ath12k):
           - enable AHB support for IPQ5332
           - add monitor interface support to QCN9274
           - add multi-link operation support to WCN7850
           - add 802.11d scan offload support to WCN7850
           - monitor mode for WCN7850, better 6 GHz regulatory
       - Qualcomm (ath11k):
           - restore hibernation support
       - MediaTek (mt76):
           - WiFi-7 improvements
           - implement support for mt7990
       - Intel (iwlwifi):
           - enhanced multi-link single-radio (EMLSR) support on 5 GHz links
           - rework device configuration
       - RealTek (rtw88):
           - improve throughput for RTL8814AU
       - RealTek (rtw89):
           - add multi-link operation support
           - STA/P2P concurrency improvements
           - support different SAR configs by antenna

   - Bluetooth:
       - introduce HCI Driver protocol
       - btintel_pcie: do not generate coredump for diagnostic events
       - btusb: add HCI Drv commands for configuring altsetting
       - btusb: add RTL8851BE device 0x0bda:0xb850
       - btusb: add new VID/PID 13d3/3584 for MT7922
       - btusb: add new VID/PID 13d3/3630 and 13d3/3613 for MT7925
       - btnxpuart: implement host-wakeup feature"

* tag 'net-next-6.16' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1611 commits)
  selftests/bpf: Fix bpf selftest build warning
  selftests: netfilter: Fix skip of wildcard interface test
  net: phy: mscc: Stop clearing the the UDPv4 checksum for L2 frames
  net: openvswitch: Fix the dead loop of MPLS parse
  calipso: Don't call calipso functions for AF_INET sk.
  selftests/tc-testing: Add a test for HFSC eltree double add with reentrant enqueue behaviour on netem
  net_sched: hfsc: Address reentrant enqueue adding class to eltree twice
  octeontx2-pf: QOS: Refactor TC_HTB_LEAF_DEL_LAST callback
  octeontx2-pf: QOS: Perform cache sync on send queue teardown
  net: mana: Add support for Multi Vports on Bare metal
  net: devmem: ncdevmem: remove unused variable
  net: devmem: ksft: upgrade rx test to send 1K data
  net: devmem: ksft: add 5 tuple FS support
  net: devmem: ksft: add exit_wait to make rx test pass
  net: devmem: ksft: add ipv4 support
  net: devmem: preserve sockc_err
  page_pool: fix ugly page_pool formatting
  net: devmem: move list_add to net_devmem_bind_dmabuf.
  selftests: netfilter: nft_queue.sh: include file transfer duration in log message
  net: phy: mscc: Fix memory leak when using one step timestamping
  ...
2025-05-28 15:24:36 -07:00
Mina Almasry
170ebc60b7 page_pool: fix ugly page_pool formatting
Minor cleanup; this line is badly formatted.

Signed-off-by: Mina Almasry <almasrymina@google.com>
Acked-by: Stanislav Fomichev <sdf@fomichev.me>
Link: https://patch.msgid.link/20250523230524.1107879-3-almasrymina@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-05-27 19:19:35 -07:00
Mina Almasry
88e47c93b3 net: devmem: move list_add to net_devmem_bind_dmabuf.
It's annoying for the list_add to be outside net_devmem_bind_dmabuf, but
the list_del is in net_devmem_unbind_dmabuf. Make it consistent by
having both the list_add/del be inside the net_devmem_[un]bind_dmabuf.

Cc: ap420073@gmail.com
Signed-off-by: Mina Almasry <almasrymina@google.com>
Tested-by: Taehee Yoo <ap420073@gmail.com>
Acked-by: Stanislav Fomichev <sdf@fomichev.me>
Link: https://patch.msgid.link/20250523230524.1107879-2-almasrymina@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-05-27 19:19:35 -07:00
Bui Quang Minh
28fcb4b56f xsk: add missing virtual address conversion for page
In commit 7ead4405e0 ("xsk: convert xdp_copy_frags_from_zc() to use
page_pool_dev_alloc()"), when converting from netmem to page, I missed a
call to page_address() around skb_frag_page(frag) to get the virtual
address of the page. This commit uses skb_frag_address() helper to fix
the issue.

Fixes: 7ead4405e0 ("xsk: convert xdp_copy_frags_from_zc() to use page_pool_dev_alloc()")
Reviewed-by: Alexander Lobakin <aleksander.lobakin@intel.com>
Signed-off-by: Bui Quang Minh <minhquangbui99@gmail.com>
Link: https://patch.msgid.link/20250522040115.5057-1-minhquangbui99@gmail.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2025-05-27 11:46:47 +02:00
Kees Cook
ae9fcd5a0f net: core: Convert dev_set_mac_address_user() to use struct sockaddr_storage
Convert callers of dev_set_mac_address_user() to use struct
sockaddr_storage. Add sanity checks on dev->addr_len usage.

Signed-off-by: Kees Cook <kees@kernel.org>
Acked-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Link: https://patch.msgid.link/20250521204619.2301870-8-kees@kernel.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2025-05-27 08:25:43 +02:00
Kees Cook
6b12e0a3c3 rtnetlink: do_setlink: Use struct sockaddr_storage
Instead of a heap allocating a variably sized struct sockaddr and lying
about the type in the call to netif_set_mac_address(), use a stack
allocated struct sockaddr_storage. This lets us drop the cast and avoid
the allocation.

Putting "ss" on the stack means it will get a reused stack slot since
it is the same size (128B) as other existing single-scope stack variables,
like the vfinfo array (128B), so no additional stack space is used by
this function.

Acked-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Signed-off-by: Kees Cook <kees@kernel.org>
Link: https://patch.msgid.link/20250521204619.2301870-7-kees@kernel.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2025-05-27 08:25:43 +02:00
Kees Cook
9ca6804ab7 net: core: Convert dev_set_mac_address() to struct sockaddr_storage
All users of dev_set_mac_address() are now using a struct sockaddr_storage.
Convert the internal data type to struct sockaddr_storage, drop the casts,
and update pointer types.

Acked-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Signed-off-by: Kees Cook <kees@kernel.org>
Link: https://patch.msgid.link/20250521204619.2301870-6-kees@kernel.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2025-05-27 08:25:43 +02:00
Kees Cook
161972650d net: core: Switch netif_set_mac_address() to struct sockaddr_storage
In order to avoid passing around struct sockaddr that has a size the
compiler cannot reason about (nor track at runtime), convert
netif_set_mac_address() to take struct sockaddr_storage. This is just a
cast conversion, so there is are no binary changes. Following patches
will make actual allocation changes.

Acked-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Signed-off-by: Kees Cook <kees@kernel.org>
Link: https://patch.msgid.link/20250521204619.2301870-2-kees@kernel.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2025-05-27 08:25:42 +02:00
Kees Cook
ed449ddbd8 net: core: Convert inet_addr_is_any() to sockaddr_storage
All the callers of inet_addr_is_any() have a sockaddr_storage-backed
sockaddr. Avoid casts and switch prototype to the actual object being
used.

Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> # SCSI
Signed-off-by: Kees Cook <kees@kernel.org>
Link: https://patch.msgid.link/20250521204619.2301870-1-kees@kernel.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2025-05-27 08:25:42 +02:00
Linus Torvalds
7d7a103d29 vfs-6.16-rc1.pidfs
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Merge tag 'vfs-6.16-rc1.pidfs' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs

Pull pidfs updates from Christian Brauner:
 "Features:

   - Allow handing out pidfds for reaped tasks for AF_UNIX SO_PEERPIDFD
     socket option

     SO_PEERPIDFD is a socket option that allows to retrieve a pidfd for
     the process that called connect() or listen(). This is heavily used
     to safely authenticate clients in userspace avoiding security bugs
     due to pid recycling races (dbus, polkit, systemd, etc.)

     SO_PEERPIDFD currently doesn't support handing out pidfds if the
     sk->sk_peer_pid thread-group leader has already been reaped. In
     this case it currently returns EINVAL. Userspace still wants to get
     a pidfd for a reaped process to have a stable handle it can pass
     on. This is especially useful now that it is possible to retrieve
     exit information through a pidfd via the PIDFD_GET_INFO ioctl()'s
     PIDFD_INFO_EXIT flag

     Another summary has been provided by David Rheinsberg:

      > A pidfd can outlive the task it refers to, and thus user-space
      > must already be prepared that the task underlying a pidfd is
      > gone at the time they get their hands on the pidfd. For
      > instance, resolving the pidfd to a PID via the fdinfo must be
      > prepared to read `-1`.
      >
      > Despite user-space knowing that a pidfd might be stale, several
      > kernel APIs currently add another layer that checks for this. In
      > particular, SO_PEERPIDFD returns `EINVAL` if the peer-task was
      > already reaped, but returns a stale pidfd if the task is reaped
      > immediately after the respective alive-check.
      >
      > This has the unfortunate effect that user-space now has two ways
      > to check for the exact same scenario: A syscall might return
      > EINVAL/ESRCH/... *or* the pidfd might be stale, even though
      > there is no particular reason to distinguish both cases. This
      > also propagates through user-space APIs, which pass on pidfds.
      > They must be prepared to pass on `-1` *or* the pidfd, because
      > there is no guaranteed way to get a stale pidfd from the kernel.
      >
      > Userspace must already deal with a pidfd referring to a reaped
      > task as the task may exit and get reaped at any time will there
      > are still many pidfds referring to it

     In order to allow handing out reaped pidfd SO_PEERPIDFD needs to
     ensure that PIDFD_INFO_EXIT information is available whenever a
     pidfd for a reaped task is created by PIDFD_INFO_EXIT. The uapi
     promises that reaped pidfds are only handed out if it is guaranteed
     that the caller sees the exit information:

     TEST_F(pidfd_info, success_reaped)
     {
             struct pidfd_info info = {
                     .mask = PIDFD_INFO_CGROUPID | PIDFD_INFO_EXIT,
             };

             /*
              * Process has already been reaped and PIDFD_INFO_EXIT been set.
              * Verify that we can retrieve the exit status of the process.
              */
             ASSERT_EQ(ioctl(self->child_pidfd4, PIDFD_GET_INFO, &info), 0);
             ASSERT_FALSE(!!(info.mask & PIDFD_INFO_CREDS));
             ASSERT_TRUE(!!(info.mask & PIDFD_INFO_EXIT));
             ASSERT_TRUE(WIFEXITED(info.exit_code));
             ASSERT_EQ(WEXITSTATUS(info.exit_code), 0);
     }

     To hand out pidfds for reaped processes we thus allocate a pidfs
     entry for the relevant sk->sk_peer_pid at the time the
     sk->sk_peer_pid is stashed and drop it when the socket is
     destroyed. This guarantees that exit information will always be
     recorded for the sk->sk_peer_pid task and we can hand out pidfds
     for reaped processes

   - Hand a pidfd to the coredump usermode helper process

     Give userspace a way to instruct the kernel to install a pidfd for
     the crashing process into the process started as a usermode helper.
     There's still tricky race-windows that cannot be easily or
     sometimes not closed at all by userspace. There's various ways like
     looking at the start time of a process to make sure that the
     usermode helper process is started after the crashing process but
     it's all very very brittle and fraught with peril

     The crashed-but-not-reaped process can be killed by userspace
     before coredump processing programs like systemd-coredump have had
     time to manually open a PIDFD from the PID the kernel provides
     them, which means they can be tricked into reading from an
     arbitrary process, and they run with full privileges as they are
     usermode helper processes

     Even if that specific race-window wouldn't exist it's still the
     safest and cleanest way to let the kernel provide the pidfd
     directly instead of requiring userspace to do it manually. In
     parallel with this commit we already have systemd adding support
     for this in [1]

     When the usermode helper process is forked we install a pidfd file
     descriptor three into the usermode helper's file descriptor table
     so it's available to the exec'd program

     Since usermode helpers are either children of the system_unbound_wq
     workqueue or kthreadd we know that the file descriptor table is
     empty and can thus always use three as the file descriptor number

     Note, that we'll install a pidfd for the thread-group leader even
     if a subthread is calling do_coredump(). We know that task linkage
     hasn't been removed yet and even if this @current isn't the actual
     thread-group leader we know that the thread-group leader cannot be
     reaped until
     @current has exited

   - Allow telling when a task has not been found from finding the wrong
     task when creating a pidfd

     We currently report EINVAL whenever a struct pid has no tasked
     attached anymore thereby conflating two concepts:

      (1) The task has already been reaped

      (2) The caller requested a pidfd for a thread-group leader but the
          pid actually references a struct pid that isn't used as a
          thread-group leader

     This is causing issues for non-threaded workloads as in where they
     expect ESRCH to be reported, not EINVAL

     So allow userspace to reliably distinguish between (1) and (2)

   - Make it possible to detect when a pidfs entry would outlive the
     struct pid it pinned

   - Add a range of new selftests

  Cleanups:

   - Remove unneeded NULL check from pidfd_prepare() for passed struct
     pid

   - Avoid pointless reference count bump during release_task()

  Fixes:

   - Various fixes to the pidfd and coredump selftests

   - Fix error handling for replace_fd() when spawning coredump usermode
     helper"

* tag 'vfs-6.16-rc1.pidfs' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs:
  pidfs: detect refcount bugs
  coredump: hand a pidfd to the usermode coredump helper
  coredump: fix error handling for replace_fd()
  pidfs: move O_RDWR into pidfs_alloc_file()
  selftests: coredump: Raise timeout to 2 minutes
  selftests: coredump: Fix test failure for slow machines
  selftests: coredump: Properly initialize pointer
  net, pidfs: enable handing out pidfds for reaped sk->sk_peer_pid
  pidfs: get rid of __pidfd_prepare()
  net, pidfs: prepare for handing out pidfds for reaped sk->sk_peer_pid
  pidfs: register pid in pidfs
  net, pidfd: report EINVAL for ESRCH
  release_task: kill the no longer needed get/put_pid(thread_pid)
  pidfs: ensure consistent ENOENT/ESRCH reporting
  exit: move wake_up_all() pidfd waiters into __unhash_process()
  selftest/pidfd: add test for thread-group leader pidfd open for thread
  pidfd: improve uapi when task isn't found
  pidfd: remove unneeded NULL check from pidfd_prepare()
  selftests/pidfd: adapt to recent changes
2025-05-26 10:30:02 -07:00
Qiu Yutan
e45b7196df net: neigh: use kfree_skb_reason() in neigh_resolve_output() and neigh_connected_output()
Replace kfree_skb() used in neigh_resolve_output() and
neigh_connected_output() with kfree_skb_reason().

Following new skb drop reason is added:
/* failed to fill the device hard header */
SKB_DROP_REASON_NEIGH_HH_FILLFAIL

Signed-off-by: Qiu Yutan <qiu.yutan@zte.com.cn>
Signed-off-by: Jiang Kun <jiang.kun2@zte.com.cn>
Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Reviewed-by: Xu Xin <xu.xin16@zte.com.cn>
Signed-off-by: David S. Miller <davem@davemloft.net>
2025-05-26 10:03:13 +01:00
Stanislav Fomichev
384492c48e net: devmem: support single IOV with sendmsg
sendmsg() with a single iov becomes ITER_UBUF, sendmsg() with multiple
iovs becomes ITER_IOVEC. iter_iov_len does not return correct
value for UBUF, so teach to treat UBUF differently.

Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Pavel Begunkov <asml.silence@gmail.com>
Cc: Mina Almasry <almasrymina@google.com>
Fixes: bd61848900 ("net: devmem: Implement TX path")
Signed-off-by: Stanislav Fomichev <stfomichev@gmail.com>
Acked-by: Mina Almasry <almasrymina@google.com>
Reviewed-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2025-05-26 10:00:48 +01:00
Kuniyuki Iwashima
77cbe1a6d8 af_unix: Introduce SO_PASSRIGHTS.
As long as recvmsg() or recvmmsg() is used with cmsg, it is not
possible to avoid receiving file descriptors via SCM_RIGHTS.

This behaviour has occasionally been flagged as problematic, as
it can be (ab)used to trigger DoS during close(), for example, by
passing a FUSE-controlled fd or a hung NFS fd.

For instance, as noted on the uAPI Group page [0], an untrusted peer
could send a file descriptor pointing to a hung NFS mount and then
close it.  Once the receiver calls recvmsg() with msg_control, the
descriptor is automatically installed, and then the responsibility
for the final close() now falls on the receiver, which may result
in blocking the process for a long time.

Regarding this, systemd calls cmsg_close_all() [1] after each
recvmsg() to close() unwanted file descriptors sent via SCM_RIGHTS.

However, this cannot work around the issue at all, because the final
fput() may still occur on the receiver's side once sendmsg() with
SCM_RIGHTS succeeds.  Also, even filtering by LSM at recvmsg() does
not work for the same reason.

Thus, we need a better way to refuse SCM_RIGHTS at sendmsg().

Let's introduce SO_PASSRIGHTS to disable SCM_RIGHTS.

Note that this option is enabled by default for backward
compatibility.

Link: https://uapi-group.org/kernel-features/#disabling-reception-of-scm_rights-for-af_unix-sockets #[0]
Link: https://github.com/systemd/systemd/blob/v257.5/src/basic/fd-util.c#L612-L628 #[1]
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2025-05-23 10:24:18 +01:00
Kuniyuki Iwashima
0e81cfd971 af_unix: Move SOCK_PASS{CRED,PIDFD,SEC} to struct sock.
As explained in the next patch, SO_PASSRIGHTS would have a problem
if we assigned a corresponding bit to socket->flags, so it must be
managed in struct sock.

Mixing socket->flags and sk->sk_flags for similar options will look
confusing, and sk->sk_flags does not have enough space on 32bit system.

Also, as mentioned in commit 16e5726269 ("af_unix: dont send
SCM_CREDENTIALS by default"), SOCK_PASSCRED and SOCK_PASSPID handling
is known to be slow, and managing the flags in struct socket cannot
avoid that for embryo sockets.

Let's move SOCK_PASS{CRED,PIDFD,SEC} to struct sock.

While at it, other SOCK_XXX flags in net.h are grouped as enum.

Note that assign_bit() was atomic, so the writer side is moved down
after lock_sock() in setsockopt(), but the bit is only read once
in sendmsg() and recvmsg(), so lock_sock() is not needed there.

Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2025-05-23 10:24:18 +01:00
Kuniyuki Iwashima
7d8d93fdde net: Restrict SO_PASS{CRED,PIDFD,SEC} to AF_{UNIX,NETLINK,BLUETOOTH}.
SCM_CREDENTIALS and SCM_SECURITY can be recv()ed by calling
scm_recv() or scm_recv_unix(), and SCM_PIDFD is only used by
scm_recv_unix().

scm_recv() is called from AF_NETLINK and AF_BLUETOOTH.

scm_recv_unix() is literally called from AF_UNIX.

Let's restrict SO_PASSCRED and SO_PASSSEC to such sockets and
SO_PASSPIDFD to AF_UNIX only.

Later, SOCK_PASS{CRED,PIDFD,SEC} will be moved to struct sock
and united with another field.

Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2025-05-23 10:24:18 +01:00
Kuniyuki Iwashima
ae4f2f59e1 tcp: Restrict SO_TXREHASH to TCP socket.
sk->sk_txrehash is only used for TCP.

Let's restrict SO_TXREHASH to TCP to reflect this.

Later, we will make sk_txrehash a part of the union for other
protocol families.

Note that we need to modify BPF selftest not to get/set
SO_TEREHASH for non-TCP sockets.

Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2025-05-23 10:24:18 +01:00
Kuniyuki Iwashima
38b95d588f scm: Move scm_recv() from scm.h to scm.c.
scm_recv() has been placed in scm.h since the pre-git era for no
particular reason (I think), which makes the file really fragile.

For example, when you move SOCK_PASSCRED from include/linux/net.h to
enum sock_flags in include/net/sock.h, you will see weird build failure
due to terrible dependency.

To avoid the build failure in the future, let's move scm_recv(_unix())?
and its callees to scm.c.

Note that only scm_recv() needs to be exported for Bluetooth.

scm_send() should be moved to scm.c too, but I'll revisit later.

Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2025-05-23 10:24:18 +01:00
Jiayuan Chen
8259eb0e06 bpf, sockmap: Avoid using sk_socket after free when sending
The sk->sk_socket is not locked or referenced in backlog thread, and
during the call to skb_send_sock(), there is a race condition with
the release of sk_socket. All types of sockets(tcp/udp/unix/vsock)
will be affected.

Race conditions:
'''
CPU0                               CPU1

backlog::skb_send_sock
  sendmsg_unlocked
    sock_sendmsg
      sock_sendmsg_nosec
                                   close(fd):
                                     ...
                                     ops->release() -> sock_map_close()
                                     sk_socket->ops = NULL
                                     free(socket)
      sock->ops->sendmsg
            ^
            panic here
'''

The ref of psock become 0 after sock_map_close() executed.
'''
void sock_map_close()
{
    ...
    if (likely(psock)) {
    ...
    // !! here we remove psock and the ref of psock become 0
    sock_map_remove_links(sk, psock)
    psock = sk_psock_get(sk);
    if (unlikely(!psock))
        goto no_psock; <=== Control jumps here via goto
        ...
        cancel_delayed_work_sync(&psock->work); <=== not executed
        sk_psock_put(sk, psock);
        ...
}
'''

Based on the fact that we already wait for the workqueue to finish in
sock_map_close() if psock is held, we simply increase the psock
reference count to avoid race conditions.

With this patch, if the backlog thread is running, sock_map_close() will
wait for the backlog thread to complete and cancel all pending work.

If no backlog running, any pending work that hasn't started by then will
fail when invoked by sk_psock_get(), as the psock reference count have
been zeroed, and sk_psock_drop() will cancel all jobs via
cancel_delayed_work_sync().

In summary, we require synchronization to coordinate the backlog thread
and close() thread.

The panic I catched:
'''
Workqueue: events sk_psock_backlog
RIP: 0010:sock_sendmsg+0x21d/0x440
RAX: 0000000000000000 RBX: ffffc9000521fad8 RCX: 0000000000000001
...
Call Trace:
 <TASK>
 ? die_addr+0x40/0xa0
 ? exc_general_protection+0x14c/0x230
 ? asm_exc_general_protection+0x26/0x30
 ? sock_sendmsg+0x21d/0x440
 ? sock_sendmsg+0x3e0/0x440
 ? __pfx_sock_sendmsg+0x10/0x10
 __skb_send_sock+0x543/0xb70
 sk_psock_backlog+0x247/0xb80
...
'''

Fixes: 4b4647add7 ("sock_map: avoid race between sock_map_close and sk_psock_put")
Reported-by: Michal Luczaj <mhal@rbox.co>
Signed-off-by: Jiayuan Chen <jiayuan.chen@linux.dev>
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Reviewed-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/r/20250516141713.291150-1-jiayuan.chen@linux.dev
2025-05-22 16:16:37 -07:00
Eric Dumazet
945301db34 net: add debug checks in ____napi_schedule() and napi_poll()
While tracking an IDPF bug, I found that idpf_vport_splitq_napi_poll()
was not following NAPI rules.

It can indeed return @budget after napi_complete() has been called.

Add two debug conditions in networking core to hopefully catch
this kind of bugs sooner.

IDPF bug will be fixed in a separate patch.

[   72.441242] repoll requested for device eth1 idpf_vport_splitq_napi_poll [idpf] but napi is not scheduled.
[   72.446291] list_del corruption. next->prev should be ff31783d93b14040, but was ff31783d93b10080. (next=ff31783d93b10080)
[   72.446659] kernel BUG at lib/list_debug.c:67!
[   72.446816] Oops: invalid opcode: 0000 [#1] SMP DEBUG_PAGEALLOC NOPTI
[   72.447031] CPU: 156 UID: 0 PID: 16258 Comm: ip Tainted: G        W           6.15.0-dbg-DEV #1944 NONE
[   72.447340] Tainted: [W]=WARN
[   72.447702] RIP: 0010:__list_del_entry_valid_or_report (lib/list_debug.c:65)
[   72.450630] Call Trace:
[   72.450720]  <IRQ>
[   72.450797] net_rx_action (include/linux/list.h:215 include/linux/list.h:287 net/core/dev.c:7385 net/core/dev.c:7516)
[   72.450928] ? lock_release (kernel/locking/lockdep.c:?)
[   72.451059] ? clockevents_program_event (kernel/time/clockevents.c:?)
[   72.451222] handle_softirqs (kernel/softirq.c:579)
[   72.451356] ? do_softirq (kernel/softirq.c:480)
[   72.451480] ? idpf_vc_xn_exec (drivers/net/ethernet/intel/idpf/idpf_virtchnl.c:462) idpf
[   72.451635] do_softirq (kernel/softirq.c:480)
[   72.451750]  </IRQ>
[   72.451828]  <TASK>
[   72.451905] __local_bh_enable_ip (kernel/softirq.c:?)
[   72.452051] idpf_vc_xn_exec (drivers/net/ethernet/intel/idpf/idpf_virtchnl.c:462) idpf
[   72.452210] idpf_send_delete_queues_msg (drivers/net/ethernet/intel/idpf/idpf_virtchnl.c:2083) idpf
[   72.452390] idpf_vport_stop (drivers/net/ethernet/intel/idpf/idpf_lib.c:837 drivers/net/ethernet/intel/idpf/idpf_lib.c:868) idpf
[   72.452541] ? idpf_vport_stop (include/linux/bottom_half.h:? include/linux/netdevice.h:4762 drivers/net/ethernet/intel/idpf/idpf_lib.c:855) idpf
[   72.452695] idpf_initiate_soft_reset (drivers/net/ethernet/intel/idpf/idpf_lib.c:?) idpf
[   72.452867] idpf_change_mtu (drivers/net/ethernet/intel/idpf/idpf_lib.c:2189) idpf
[   72.453015] netif_set_mtu_ext (net/core/dev.c:9437)
[   72.453157] ? packet_notifier (include/linux/rcupdate.h:331 include/linux/rcupdate.h:841 net/packet/af_packet.c:4240)
[   72.453292] netif_set_mtu (net/core/dev.c:9515)
[   72.453416] dev_set_mtu (net/core/dev_api.c:?)
[   72.453534] bond_change_mtu (drivers/net/bonding/bond_main.c:4833)
[   72.453666] netif_set_mtu_ext (net/core/dev.c:9437)
[   72.453803] do_setlink (net/core/rtnetlink.c:3116)
[   72.453925] ? rtnl_newlink (net/core/rtnetlink.c:3901)
[   72.454055] ? rtnl_newlink (net/core/rtnetlink.c:3901)
[   72.454185] ? rtnl_newlink (net/core/rtnetlink.c:3901)
[   72.454314] ? trace_contention_end (include/trace/events/lock.h:122)
[   72.454467] ? __mutex_lock (arch/x86/include/asm/preempt.h:85 kernel/locking/mutex.c:611 kernel/locking/mutex.c:746)
[   72.454597] ? cap_capable (include/trace/events/capability.h:26)
[   72.454721] ? security_capable (security/security.c:?)
[   72.454857] rtnl_newlink (net/core/rtnetlink.c:?)
[   72.454982] ? lock_is_held_type (kernel/locking/lockdep.c:5599 kernel/locking/lockdep.c:5938)
[   72.455121] ? __lock_acquire (kernel/locking/lockdep.c:?)
[   72.455256] ? __change_page_attr_set_clr (arch/x86/mm/pat/set_memory.c:685)
[   72.455438] ? __lock_acquire (kernel/locking/lockdep.c:?)
[   72.455582] ? rtnetlink_rcv_msg (include/linux/rcupdate.h:331 include/linux/rcupdate.h:841 net/core/rtnetlink.c:6885)
[   72.455721] ? lock_acquire (kernel/locking/lockdep.c:5866)
[   72.455848] ? rtnetlink_rcv_msg (include/linux/rcupdate.h:331 include/linux/rcupdate.h:841 net/core/rtnetlink.c:6885)
[   72.455987] ? lock_release (kernel/locking/lockdep.c:?)
[   72.456117] ? rcu_read_unlock (include/linux/rcupdate.h:341 include/linux/rcupdate.h:871)
[   72.456249] ? __pfx_rtnl_newlink (net/core/rtnetlink.c:3956)
[   72.456388] rtnetlink_rcv_msg (net/core/rtnetlink.c:6955)
[   72.456526] ? rtnetlink_rcv_msg (include/linux/rcupdate.h:331 include/linux/rcupdate.h:841 net/core/rtnetlink.c:6885)
[   72.456671] ? lock_acquire (kernel/locking/lockdep.c:5866)
[   72.456802] ? net_generic (include/linux/rcupdate.h:331 include/linux/rcupdate.h:841 include/net/netns/generic.h:45)
[   72.456929] ? __pfx_rtnetlink_rcv_msg (net/core/rtnetlink.c:6858)
[   72.457082] netlink_rcv_skb (net/netlink/af_netlink.c:2534)
[   72.457212] netlink_unicast (net/netlink/af_netlink.c:1313)
[   72.457344] netlink_sendmsg (net/netlink/af_netlink.c:1883)
[   72.457476] __sock_sendmsg (net/socket.c:712)
[   72.457602] ____sys_sendmsg (net/socket.c:?)
[   72.457735] ? _copy_from_user (arch/x86/include/asm/uaccess_64.h:126 arch/x86/include/asm/uaccess_64.h:134 arch/x86/include/asm/uaccess_64.h:141 include/linux/uaccess.h:178 lib/usercopy.c:18)
[   72.457875] ___sys_sendmsg (net/socket.c:2620)
[   72.458042] ? __call_rcu_common (arch/x86/include/asm/irqflags.h:42 arch/x86/include/asm/irqflags.h:119 arch/x86/include/asm/irqflags.h:159 kernel/rcu/tree.c:3107)
[   72.458185] ? mntput_no_expire (include/linux/rcupdate.h:331 include/linux/rcupdate.h:841 fs/namespace.c:1457)
[   72.458324] ? lock_acquire (kernel/locking/lockdep.c:5866)
[   72.458451] ? mntput_no_expire (include/linux/rcupdate.h:331 include/linux/rcupdate.h:841 fs/namespace.c:1457)
[   72.458588] ? lock_release (kernel/locking/lockdep.c:?)
[   72.458718] ? mntput_no_expire (include/linux/rcupdate.h:331 include/linux/rcupdate.h:841 fs/namespace.c:1457)
[   72.458856] __x64_sys_sendmsg (net/socket.c:2652)
[   72.458997] ? do_syscall_64 (arch/x86/include/asm/irqflags.h:42 arch/x86/include/asm/irqflags.h:119 include/linux/entry-common.h:198 arch/x86/entry/syscall_64.c:90)
[   72.459136] do_syscall_64 (arch/x86/entry/syscall_64.c:?)
[   72.459259] ? exc_page_fault (arch/x86/mm/fault.c:1542)
[   72.459387] entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130)
[   72.459555] RIP: 0033:0x7fd15f17cbd0

Signed-off-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20250520121908.1805732-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-05-21 20:44:11 -07:00
Eric Biggers
c93f75b2d7 net: remove skb_copy_and_hash_datagram_iter()
Now that skb_copy_and_hash_datagram_iter() is no longer used, remove it.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Link: https://patch.msgid.link/20250519175012.36581-11-ebiggers@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-05-21 15:40:17 -07:00
Eric Biggers
ea6342d989 net: add skb_copy_and_crc32c_datagram_iter()
Since skb_copy_and_hash_datagram_iter() is used only with CRC32C, the
crypto_ahash abstraction provides no value.  Add
skb_copy_and_crc32c_datagram_iter() which just calls crc32c() directly.

This is faster and simpler.  It also doesn't have the weird dependency
issue where skb_copy_and_hash_datagram_iter() depends on
CONFIG_CRYPTO_HASH=y without that being expressed explicitly in the
kconfig (presumably because it was too heavyweight for NET to select).
The new function is conditional on the hidden boolean symbol NET_CRC32C,
which selects CRC32.  So it gets compiled only when something that
actually needs CRC32C packet checksums is enabled, it has no implicit
dependency, and it doesn't depend on the heavyweight crypto layer.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Link: https://patch.msgid.link/20250519175012.36581-9-ebiggers@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-05-21 15:40:17 -07:00
Eric Biggers
70c96c7cb9 net: fold __skb_checksum() into skb_checksum()
Now that the only remaining caller of __skb_checksum() is
skb_checksum(), fold __skb_checksum() into skb_checksum().  This makes
struct skb_checksum_ops unnecessary, so remove that too and simply do
the "regular" net checksum.  It also makes the wrapper functions
csum_partial_ext() and csum_block_add_ext() unnecessary, so remove those
too and just use the underlying functions.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Link: https://patch.msgid.link/20250519175012.36581-7-ebiggers@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-05-21 15:40:16 -07:00
Eric Biggers
86edc94da1 net: use skb_crc32c() in skb_crc32c_csum_help()
Instead of calling __skb_checksum() with a skb_checksum_ops struct that
does CRC32C, just call the new function skb_crc32c().  This is faster
and simpler.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Link: https://patch.msgid.link/20250519175012.36581-4-ebiggers@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-05-21 15:39:59 -07:00
Eric Biggers
a5bd029c73 net: add skb_crc32c()
Add skb_crc32c(), which calculates the CRC32C of a sk_buff.  It will
replace __skb_checksum(), which unnecessarily supports arbitrary
checksums.  Compared to __skb_checksum(), skb_crc32c():

   - Uses the correct type for CRC32C values (u32, not __wsum).

   - Does not require the caller to provide a skb_checksum_ops struct.

   - Is faster because it does not use indirect calls and does not use
     the very slow crc32c_combine().

According to commit 2817a336d4 ("net: skb_checksum: allow custom
update/combine for walking skb") which added __skb_checksum(), the
original motivation for the abstraction layer was to avoid code
duplication for CRC32C and other checksums in the future.  However:

   - No additional checksums showed up after CRC32C.  __skb_checksum()
     is only used with the "regular" net checksum and CRC32C.

   - Indirect calls are expensive.  Commit 2544af0344 ("net: avoid
     indirect calls in L4 checksum calculation") worked around this
     using the INDIRECT_CALL_1 macro. But that only avoided the indirect
     call for the net checksum, and at the cost of an extra branch.

   - The checksums use different types (__wsum and u32), causing casts
     to be needed.

   - It made the checksums of fragments be combined (rather than
     chained) for both checksums, despite this being highly
     counterproductive for CRC32C due to how slow crc32c_combine() is.
     This can clearly be seen in commit 4c2f245496 ("sctp: linearize
     early if it's not GSO") which tried to work around this performance
     bug.  With a dedicated function for each checksum, we can instead
     just use the proper strategy for each checksum.

As shown by the following tables, the new function skb_crc32c() is
faster than __skb_checksum(), with the improvement varying greatly from
5% to 2500% depending on the case.  The largest improvements come from
fragmented packets, mainly due to eliminating the inefficient
crc32c_combine().  But linear packets are improved too, especially
shorter ones, mainly due to eliminating indirect calls.  These
benchmarks were done on AMD Zen 5.  On that CPU, Linux uses IBRS instead
of retpoline; an even greater improvement might be seen with retpoline:

    Linear sk_buffs

        Length in bytes    __skb_checksum cycles    skb_crc32c cycles
        ===============    =====================    =================
                     64                       43                   18
                    256                       94                   77
                   1420                      204                  161
                  16384                     1735                 1642

    Nonlinear sk_buffs (even split between head and one fragment)

        Length in bytes    __skb_checksum cycles    skb_crc32c cycles
        ===============    =====================    =================
                     64                      579                   22
                    256                      829                   77
                   1420                     1506                  194
                  16384                     4365                 1682

Signed-off-by: Eric Biggers <ebiggers@google.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Link: https://patch.msgid.link/20250519175012.36581-3-ebiggers@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-05-21 15:39:58 -07:00
Eric Biggers
55d22ee035 net: introduce CONFIG_NET_CRC32C
Add a hidden kconfig symbol NET_CRC32C that will group together the
functions that calculate CRC32C checksums of packets, so that these
don't have to be built into NET-enabled kernels that don't need them.

Make skb_crc32c_csum_help() (which is called only when IP_SCTP is
enabled) conditional on this symbol, and make IP_SCTP select it.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Link: https://patch.msgid.link/20250519175012.36581-2-ebiggers@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-05-21 15:39:58 -07:00