linux-toradex.git/net, branch master

Merge tag '9p-for-7.2-rc1' of https://github.com/martinetd/linux

2026-06-21T17:26:31+00:00

Pull 9p updates from Dominique Martinet:
 "Asides of the avalanche of LLM-driven fixes, there are a couple of big
  changes this cycle:

   - negative dentry and symlink cache

   - a way out of the unkillable "io_wait_event_killable" (because it
     looped around waiting for the request flush to come back from
     server; this has been bugging syzcaller folks since forever): I'm
     still not 100% sure about this patch, but I think it's as good as
     we'll ever get, and will keep testing a bit further in the coming
     weeks

  The rest is more noisy than usual, but shouldn't cause any trouble"

* tag '9p-for-7.2-rc1' of https://github.com/martinetd/linux:
  9p: Add missing read barrier in virtio zero-copy path
  net/9p: Replace strlen() strcpy() pair with strscpy()
  9p: skip nlink update in cacheless mode to fix WARN_ON
  net/9p: fix race condition on rdma->state in trans_rdma.c
  9p: v9fs_file_do_lock: replace WARN_ONCE with p9_debug
  9p: Enable symlink caching in page cache
  9p: Set default negative dentry retention time for cache=loose
  9p: Add mount option for negative dentry cache retention
  9p: Cache negative dentries for lookup performance
  9p: avoid returning ERR_PTR(0) from mkdir operations
  9p: avoid putting oldfid in p9_client_walk() error path
  net/9p: fix infinite loop in p9_client_rpc on fatal signal
  docs/filesystems/9p: fix broken external links
  9p: invalidate readdir buffer on seek
  9p: use kvzalloc for readdir buffer
  net/9p/usbg: Constify struct configfs_item_operations

9p: Add missing read barrier in virtio zero-copy path

2026-06-21T05:22:57+00:00

Commit 2b6e72ed747f ("9P: Add memory barriers to protect request
fields over cb/rpc threads handoff") added a read barrier after
p9_client_rpc() waits for req->status, pairing with the write barrier in
p9_client_cb(). The virtio zero-copy wait path was missed.

Add the same read barrier after the zero-copy wait before reading the
completed request.

Fixes: 2b6e72ed747f ("9P: Add memory barriers to protect request fields over cb/rpc threads handoff")
Signed-off-by: Gui-Dong Han 
Message-ID: <20260529075441.233369-1-hanguidong02@gmail.com>
Signed-off-by: Dominique Martinet

net/9p: Replace strlen() strcpy() pair with strscpy()

2026-06-21T05:22:57+00:00

Use the result of strscpy() for the overflow check.

Signed-off-by: David Laight 
Message-ID: <20260606202744.5113-3-david.laight.linux@gmail.com>
Signed-off-by: Dominique Martinet

net/9p: fix race condition on rdma->state in trans_rdma.c

2026-06-21T05:22:57+00:00

The rdma->state field is modified without holding req_lock in both
recv_done() and p9_cm_event_handler(), while rdma_request() accesses
the same field under the req_lock spinlock. This inconsistent locking
creates a race condition:

- recv_done() running in softirq completion context sets
  rdma->state = P9_RDMA_FLUSHING without acquiring req_lock

- p9_cm_event_handler() modifies rdma->state at multiple points
  (ADDR_RESOLVED, ROUTE_RESOLVED, ESTABLISHED, CLOSED) without
  req_lock

- rdma_request() uses spin_lock_irqsave(&rdma->req_lock, flags) to
  protect the read-modify-write of rdma->state

The race can cause lost state transitions: recv_done() or the CM
event handler could set state to FLUSHING/CLOSED while rdma_request()
is concurrently checking or modifying state under the lock, leading to
the FLUSHING transition being silently overwritten by CLOSING. This
corrupts the connection state machine and can cause use-after-free on
RDMA request objects during teardown.

Fix by adding req_lock protection to all rdma->state modifications in
recv_done() and p9_cm_event_handler(), matching the pattern already
used in rdma_request(). Use spin_lock_irqsave/spin_unlock_irqrestore
in the CM event handler since it can race with recv_done() which runs
in softirq context.

Tested with a kernel module that races two threads (simulating
rdma_request and recv_done/CM handler) on rdma->state with proper
locking: 5.5M+ FLUSHING writes over 27M iterations with 0 lost
transitions.

Fixes: 473c7dd1d7b5 ("9p/rdma: remove useless check in cm_event_handler")
Reported-by: Yizhou Zhao 
Reported-by: Yuxiang Yang 
Reported-by: Ao Wang 
Reported-by: Xuewei Feng 
Reported-by: Qi Li 
Reported-by: Ke Xu 
Assisted-by: GLM:GLM-5.1
Signed-off-by: Yizhou Zhao 
Message-ID: <20260529073933.77315-1-zhaoyz24@mails.tsinghua.edu.cn>
Signed-off-by: Dominique Martinet

9p: avoid putting oldfid in p9_client_walk() error path

2026-06-21T05:22:56+00:00

When p9_client_walk() is called with clone set to false, fid aliases
oldfid. If the walk subsequently fails after the request has been sent,
the error path jumps to clunk_fid, which currently calls p9_fid_put(fid)
unconditionally.

This drops a reference to oldfid even though ownership of oldfid remains
with the caller. If this is the last reference, oldfid can be clunked and
destroyed while the caller still expects it to be valid. A later use or
put of oldfid can then trigger a use-after-free or refcount underflow.

Fix this by only putting fid in the clunk_fid error path when it does not
alias oldfid, matching the existing guard in the error path below.

This can be triggered when a multi-component walk is split into multiple
p9_client_walk() calls and a later non-cloning walk fails. A reproducer
and refcount warning logs are available on request.

Fixes: b48dbb998d70 ("9p fid refcount: add p9_fid_get/put wrappers")
Cc: stable@vger.kernel.org
Reported-by: Yuxiang Yang 
Reported-by: Ao Wang 
Reported-by: Xuewei Feng 
Reported-by: Qi Li 
Reported-by: Ke Xu 
Assisted-by: GLM 5.1
Signed-off-by: Yizhou Zhao 
Message-ID: <20260528053918.53550-1-zhaoyz24@mails.tsinghua.edu.cn>
Signed-off-by: Dominique Martinet

Merge tag 'mm-stable-2026-06-18-09-26' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

2026-06-19T17:14:34+00:00

Pull MM updates from Andrew Morton:

 - "selftests/mm: clean up build output and verbosity" (Li Wang)

   Remove some noise from the MM selftests build

 - "mm: Free contiguous order-0 pages efficiently" (Ryan Roberts)

   Speed up the freeing of a batch of 0-order pages by first scanning
   them for coalescing opportunities. This is applicable to vfree() and
   to the releasing of frozen pages

 - "mm/damon: introduce DAMOS failed region quota charge ratio"
   (SeongJae Park)

   Address a DAMOS usability issue: The DAMOS quota often exhausts
   prematurely because it charges for all memory attempted, causing slow
   and inconsistent performance when actions fail on unreclaimable
   memory.

   To fix this, a new feature lets users set a smaller, flexible quota
   charge ratio (via a numerator and denominator) for failed regions.
   Since failed actions cause less overhead, reducing their quota cost
   ensures more predictable and efficient DAMOS processing

 - "selftests/cgroup: improve zswap tests robustness and support large
   page sizes" (Li Wang)

   Fix various spurious failures and improves the overall robustness of
   the cgroup zswap selftests

 - "fix MAP_DROPPABLE not supported errno" (Anthony Yznaga)

   Fix an issue in the mlock selftests on arm32

 - "mm: huge_memory: clean up defrag sysfs with shared" (Breno Leitao)

   Some maintenance work in the huge_memory code

 - "treewide: fixup gfp_t printks" (Brendan Jackman)

   Use the special vprintf() gfp_t conversion in various places

 - "mm: Fix vmemmap optimization accounting and initialization" (Muchun
   Song)

   Fix several bugs in the vmemmap optimization, mainly around incorrect
   page accounting and memmap initialization in the DAX and memory
   hotplug paths. It also fixes pageblock migratetype initialization and
   struct page initialization for ZONE_DEVICE compound pages

 - "mm/damon: repost non-hotfix reviewed patches in damon/next tree"

   A sprinkle of unrelated minor bugfixes for DAMON

 - "mm: remove page_mapped()" (David Hildenbrand)

   Remove this function from the tree, replacing it with folio_mapped()

 - "mm/damon: let DAMON be paused and resumed" (SeongJae Park)

   Allow DAMON to be paused and resumed without losing its current state

 - "kasan: hw_tags: Disable tagging for stack and page-tables" (Muhammad
   Usama Anjum)

   Simplify and speed up kasan by removing its ineffective tagging of
   stacks and page tables

 - "mm/damon/reclaim,lru_sort: monitor all system rams by default"
   (SeongJae Park)

   Simplify deployment on diverse hardware like NUMA systems by updating
   DAMON_RECLAIM and DAMON_LRU_SORT to automatically monitor the
   physical address range covering all System RAM areas by default,
   replacing the overly restrictive behavior that only targeted the
   single largest memory block to save on negligible overhead

 - "mm/damon/sysfs: document filters/ directory as deprecated" (SeongJae
   Park)

   Update some DAMON docs

 - "mm: use spinlock guards for zone lock" (Dmitry Ilvokhin)

   Switch zone->lock handling over to using the guard() mechanisms

 - "mm/filemap: tighten mmap_miss hit accounting" (fujunjie)

   Fix a flaw where the mmap_miss counter over-credited page cache hits
   during fault-arounds and page-fault retries. This results in
   significant reduction of redundant synchronous mmap readahead I/O,
   drastically cutting down execution time and gigabytes read for sparse
   random or strided memory access workloads

 - "selftests/cgroup: Fix false positive failures in test_percpu_basic"
   (Li Wang)

   Fix a couple of false-positives in the cgroup kmem selftests

 - "mm/damon/reclaim: support monitoring intervals auto-tuning"
   (SeongJae Park)

   Add a new parameter to DAMON permitting DAMON_RECLAIM to
   automatically tune DAMON's sampling and aggregation intervals

 - "mm/damon/stat: add kdamond_pid parameter" (SeongJae Park)

   Change DAMON_STAT to provide the pid of its kdamond

 - "mm/kmemleak: dedupe verbose scan output" (Breno Leitao)

   Remove large amounts of duplicated backtraces from the verbose-mode
   kmemleak output

 - "mm: remove CONFIG_HAVE_BOOTMEM_INFO_NODE (Part 1)" (David
   Hildenbrand)

   Reduce our use of CONFIG_HAVE_BOOTMEM_INFO_NODE, with a view to
   removing it entirely in a later series

 - "mm/damon: validate min_region_size to be power of 2" (Liew Rui Yan)

   Prevent users from passing a non-power-of-2 value of `addr_unit', as
   this later results in undesirable behavior

 - "mm: document read_pages and simplify usage" (Frederick Mayle)

 - "tools/mm/page-types: Fix misc bugs" (Ye Liu)

   Fix three issues in tools/mm/page-types.c

 - "mm: misc cleanups from __GFP_UNMAPPED series" (Brendan Jackman)

   Implement several cleanups in the page allocator and related code

 - "mm, swap: swap table phase IV: unify allocation" (Kairui Song)

   Unify the allocation and charging of anon and shmem swap in folios,
   provides better synchronization, consolidates the metadata
   management, hence dropping the static array and map, and improves
   performance

 - "mm/damon: introduce data attributes monitoring" (SeongJae Park(

   Extend DAMON to monitor general data attributes other than accesses

 - "mm/vmalloc: free unused pages on vrealloc() shrink" (Shivam Kalra)

   Implement the TODO in vrealloc() to unmap and free unused pages when
   shrinking across a page boundary

 - "mm/damon: documentation and comment fixes" (niecheng)

 - "remove mmap_action success, error hooks" (Lorenzo Stoakes)

   Eliminate custom hooks from mmap_action by removing the problematic
   success_hook which allowed drivers to improperly access uninitialized
   VMAs. It replaces the error_hook with a simple error-code field and
   updates the memory char driver accordingly

 - "mm/damon: minor improvements for code readability and tests"
   (SeongJae Park)

 - "mm/damon: fix macro arguments and clarify quota goals doc" (Maksym
   Shcherba)

 - "userfaultfd: merge fs/userfaultfd.c into mm/userfaultfd.c" (Mike
   Rapoport)

 - "mm/mglru: improve reclaim loop and dirty folio" (Kairui Song and
   others)

   Clean up and slightly improves MGLRU's reclaim loop and dirty
   writeback handling. Large performance improvements are measured

 - "use vma locks for proc/pid/{smaps|numa_maps} reads" (Suren
   Baghdasaryan)

   Use per-vma locks when reading /proc/pid/smaps and numa_maps similar
   to reduce contention on central mmap_lock

 - "refactors thpsize_shmem_enabled_store() and thpsize_shmem_enabled_show()"
   (Ran Xiaokai)

   Some cleanup work in the THP code

 - "selftests/memfd: fix compilation warnings" (Konstantin Khorenko)

   Fix a few build glitches in the memfd selftest code.

 - "memcg: shrink obj_stock_pcp and cache multiple objcgs" (Shakeel
   Butt)

   Resolve a 68% performance regression caused by NUMA-node cache
   thrashing around struct obj_stock_pcp by shrinking its existing
   fields and expanding it into a multi-slot array that caches up to
   five obj_cgroup pointers per CPU, allowing per-node variants of the
   same memcg to coexist within a single 64-byte cache line.

 - "zram: writeback fixes" (Sergey Senozhatsky)

   address a couple of unrelated zram writeback issues

 - "mm: switch THP shrinker to list_lru" (Johannes Weiner)

   Resolve NUMA-awareness issues and streamlines callsite interaction by
   refactoring and extending the list_lru API to completely replace the
   complex, open-coded deferred split queue for Transparent Huge Pages

 - "mm: improve large folio readahead for exec memory" (Usama Arif)

   Improve large-folio readahead on systems like 64K-page arm64 by
   preventing the mmap_miss check from permanently disabling
   target-oriented VM_EXEC readahead, and by generalizing the
   force_thp_readahead gate to support mappings with any usefully large
   maximum folio order under the cache cap.

 - "userfaultfd/pagemap: pre-existing fixes" (Kiryl Shutsemau)

   Fix a bunch of minor issues in the userfaultfd/pagemap, all of which
   were flagged by Sashiko review of proposed new material

 - "mm/sparse-vmemmap: Provide generic vmemmap_set_pmd() and
   vmemmap_check_pmd()" (Muchun Song)

   Provide generic versions of these two functions so the four
   arch-specific implementations can be removed.

 - "mm/swap, PM: hibernate: fix swapoff race in uswsusp by pinning swap
   device" (Youngjun Park)

   Address a uswsusp-vs-swapoff race and reduces the swap device
   reference taking/releasing frequency.

 - "mm/hmm: A fix and a selftest" (Dev Jain)

* tag 'mm-stable-2026-06-18-09-26' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (321 commits)
  selftests/mm/hmm-tests: test pagemap reads of PMD device-private entries
  fs/proc/task_mmu: do not warn on seeing non-migration pmd entry
  lib/test_hmm: check alloc_page_vma() return value and handle OOM
  mm/compaction: cap compact_gap() at COMPACT_CLUSTER_MAX
  mm/swap: remove redundant swap device reference in alloc/free
  mm/swap, PM: hibernate: fix swapoff race in uswsusp by pinning swap device
  mm/filemap: use folio_next_index() for start
  vmalloc: fix NULL pointer dereference in is_vm_area_hugepages()
  sparc/mm: drop vmemmap_check_pmd helper and use generic code
  loongarch/mm: drop vmemmap_check_pmd helper and use generic code
  riscv/mm: drop vmemmap_pmd helpers and use generic code
  arm64/mm: drop vmemmap_pmd helpers and use generic code
  mm/sparse-vmemmap: provide generic vmemmap_set_pmd() and vmemmap_check_pmd()
  rust: page: mark Page::nid as inline
  userfaultfd: build __VMA_UFFD_FLAGS from config-gated masks
  userfaultfd: gate must_wait writability check on pte_present()
  mm/huge_memory: preserve pmd_swp_uffd_wp on device-private PMD downgrade
  fs/proc/task_mmu: fix hugetlb self-deadlock in pagemap_scan_pte_hole()
  fs/proc/task_mmu: use huge_page_size() in pagemap_scan_hugetlb_entry()
  fs/proc/task_mmu: fix make_uffd_wp_huge_pte() prot-update race
  ...

Merge tag 'nfsd-7.2' of git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux

2026-06-18T16:14:15+00:00

Pull nfsd updates from Chuck Lever:
 "Jeff Layton wired up netlink upcalls for the auth.unix.ip and
  auth.unix.gid caches in SunRPC and the svc_export and nfsd.fh caches
  in NFSD. The new kernel-user API is more extensible and lays the
  groundwork for retiring the old pipe interface.

  The default NFS r/w block size rises to 4MB on hosts with at least
  16GB of RAM, reducing per-RPC overhead on fast networks. Smaller
  machines keep their previously computed default, and the value remains
  tunable through /proc/fs/nfsd/max_block_size.

  Chuck Lever converted the server's RPCSEC GSS Kerberos code to the
  kernel's shared crypto/krb5 library. The conversion retires and
  removes SunRPC's bespoke implementation of Kerberos v5, but keeps
  RPCSEC GSS-API.

  Continuing the xdrgen migration that converted the NLMv4 server XDR
  layer in v7.1, Chuck Lever converted the NLM version 3 server-side XDR
  layer from hand-written C to xdrgen-generated code. As with the NLMv4
  conversion in v7.1, the goals are improved memory safety, lower
  maintenance burden, and groundwork for generation of Rust code for
  this layer instead of C.

  Chuck Lever fixed an issue where lingering NFSv4 state pins a mounted
  file system after it is unexported. A new netlink-based mechanism can
  now release NLM locks and NFSv4 state by client address, by
  filesystem, and by export. Now an administrator can quiesce an export
  cleanly before unmounting it.

  The remaining patches are bug fixes, clean-ups, and minor
  optimizations, including a batch of memory-leak and use-after-free
  fixes in the ACL, lockd, and TLS handshake paths, many of them
  reported by Chris Mason. Sincere thanks to all contributors,
  reviewers, testers, and bug reporters who participated in the v7.2
  NFSD development cycle"

* tag 'nfsd-7.2' of git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux: (106 commits)
  svcrdma: wake sq waiters when the transport closes
  nfsd: reset write verifier on deferred writeback errors
  nfsd: avoid leaking pre-allocated openowner on unconfirmed retry race
  sunrpc: wait for in-flight TLS handshake callback when cancel loses race
  sunrpc: pin svc_xprt across the asynchronous TLS handshake callback
  nfsd: fix posix_acl leak on SETACL decode failure
  nfsd: fix posix_acl leak and ignored error in nfsd4_create_file
  nfsd: check get_user() return when reading princhashlen
  nfsd: fix inverted cp_ttl check in async copy reaper
  nfsd: fix dead ACL conflict guard in nfsd4_create
  NFSD: Fix SECINFO_NO_NAME decode error cleanup
  sunrpc: harden rq_procinfo lifecycle to prevent double-free
  SUNRPC: Return an error from xdr_buf_to_bvec() on overflow
  SUNRPC: Bound-check xdr_buf_to_bvec() stores before writing
  nfsd: release layout stid on setlease failure
  lockd: Avoid hashing uninitialized bytes in nlm4svc_lookup_file()
  lockd: Plug nlm_file refcount leak on cached nlm_do_fopen() failure
  lockd: Plug nlm_file leak when nlm_do_fopen() fails
  Revert "NFSD: Defer sub-object cleanup in export put callbacks"
  Revert "svcrdma: Use contiguous pages for RDMA Read sink buffers"
  ...

Merge tag 'bpf-next-7.2' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next

2026-06-17T08:18:14+00:00

Pull bpf updates from Alexei Starovoitov:
 "Major changes:

   - Recover from BPF arena page faults using a scratch page and add
     ptep_try_set() for lockless empty-slot installs on x86 and arm64.

     This allows BPF kfuncs to access arena pointers directly.

     The 'arena_direct_access' stable branch was created for this work
     and was pulled into sched-ext and bpf-next trees (Tejun Heo, Kumar
     Kartikeya Dwivedi)

   - Lift old restriction and support 6+ arguments in BPF programs and
     kfuncs on x86 and arm64 (Yonghong Song, Puranjay Mohan)

  Other features and fixes:

   - Add 24-bit BTF vlen and reclaim unused bits in the BTF UAPI to ease
     addition of new BTF kinds (Alan Maguire)

   - Raise the maximum BPF call chain depth from 8 to 16 frames (Alexei
     Starovoitov)

   - Refactor object relationship tracking in the verifier and fix a
     dynptr use-after-free bug (Amery Hung)

   - Harden the signed program loader and reject exclusive maps as inner
     maps (Daniel Borkmann)

   - Replace the verifier min/max bounds fields with a circular number
     (cnum) representation and improve 32->64 bit range refinements
     (Eduard Zingerman)

   - Introduce the arena library and runtime (libarena) with a buddy
     allocator, rbtree and SPMC queue data structures, ASAN support and
     a parallel test harness. Allow subprograms to return arena pointers
     and switch to a BTF type-tag based __arena annotation (Emil
     Tsalapatis)

   - Cache build IDs in the sleepable stackmap path and avoid faultable
     build ID reads under mm locks (Ihor Solodrai)

   - Introduce the tracing_multi link to attach a single BPF program to
     many kernel functions at once. Allow specifying the uprobe_multi
     target via FD (Jiri Olsa)

   - Extend the bpf_list family of kfuncs with bpf_list_add/del(), and
     bpf_list_is_first/is_last/empty() (Kaitao Cheng)

   - Extend the BPF syscall with common attributes support for
     prog_load, btf_load and map_create (Leon Hwang)

   - Wrap rhashtable as BPF map (Mykyta Yatsenko, Herbert Xu)

   - Add sleepable support for tracepoint programs and fix deadlocks in
     LRU map due to NMI reentry (Mykyta Yatsenko)

   - Fix OOB access in bpf_flow_keys, fix nullness analysis of inner
     arrays, enforce write checks for global subprograms (Nuoqi Gui)

   - Report the maximum combined stack depth and print a breakdown of
     instructions processed per subprogram (Paul Chaignon)

   - Add an XDP load-balancer benchmark and arm64 JIT support for stack
     arguments (Puranjay Mohan)

   - Add kfuncs to traverse over wakeup_sources (Samuel Wu)

   - Allow sleepable BPF programs to use LPM trie maps directly (Vlad
     Poenaru)

   - Many more fixes and cleanups across the verifier, BTF, sockmap,
     devmap, bpffs, security hooks, s390/riscv/loongarch JITs,
     rqspinlock, libbpf, bpftool, selftests"

* tag 'bpf-next-7.2' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (336 commits)
  selftests/bpf: Work around llvm stack overflow in crypto progs
  selftests/bpf: add test for bpf_msg_pop_data() overflow
  bpf, sockmap: fix integer overflow in bpf_msg_pop_data() bounds check
  sockmap: Fix use-after-free in udp_bpf_recvmsg()
  bpf, sockmap: keep sk_msg copy state in sync
  bpf, sockmap: Fix wrong rsge offset in bpf_msg_push_data()
  bpf, sockmap: reject overflowing copy + len in bpf_msg_push_data()
  selftsets/bpf: Retry map update on helper_fill_hashmap()
  selftests/bpf: Add test for sleepable lsm_cgroup rejection
  selftests/bpf: Add test to verify the fix for bpf_setsockopt() helper
  bpf: Fix bpf_get/setsockopt to tos for ipv4-mapped ipv6 socket
  selftests/bpf: Avoid static LLVM linking for cross builds
  selftests/bpf: Use common CFLAGS for urandom_read
  selftests/bpf: Initialize operation name before use
  tools/bpf: build: Append extra cflags
  libbpf: Initialize CFLAGS before including Makefile.include
  bpftool: Append extra host flags
  bpftool: Avoid adding EXTRA_CFLAGS to HOST_CFLAGS
  bpftool: Pass host flags to bootstrap libbpf
  selftests/bpf: correct CONFIG_PPC64 macro name in comment
  ...

Merge tag 'net-next-7.2' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next

2026-06-17T07:17:00+00:00

Pull networking updates from Jakub Kicinski:
"Core & protocols:

- Work on removing rtnl_lock protection throughout the stack
continues. In this chapter:
- don't use rtnl_lock for IPv6 multicast routing configuration
- don't take rtnl_lock in ethtool for modern drivers
- prepare Qdisc dump callbacks for rtnl_lock removal

- Support dumping just ifindex + name of all interfaces, under RCU.
It's a common operation for Netlink CLI tools (when translating
names to ifindexes) and previously required full rtnl_lock.

- Support dumping qdiscs and page pools for a specific netdev. Even
tho user space wants a dump of all netdevs, most of the time, the
OOO programming model results in repeating the dump for each
netdev. Which, in absence of a cache, leads to a O(n^2) behavior.

- Flush nexthops once on multi-nexthop removal (e.g. when device goes
down), another O(n^2) -> O(n) improvement.

- Rehash locally generated traffic to a different nexthop on
retransmit timeout.

- Honor oif when choosing nexthop for locally generated IPv6 traffic.

- Convert TCP Auth Option to crypto library, and drop non-RFC algos.

- Increase subflow limits in MPTCP to 64 and endpoint limit to 256.

- Support MPTCP signaling of IPv6 address + port (ADD_ADDR). We need
to selectively skip reporting of the standard TCP Timestamp option,
because they won't fit into the header space together (12 + 30 >
40).

- Support using bridge neighbor suppression, Duplicate Address
Detection, Gratuitous ARP and unsolicited NA forwarding - in EVPN
deployments, e.g. VXLAN fabrics (IPv4 and IPv6).

- Improve link state reporting for upper netdevs (e.g. macvlan) over
tunnel devices (again, mostly for EVPN deployments).

- Support binding GENEVE tunnels to a local address.

- Speed up UDP tunnel destruction (remove one synchronize_rcu()).

- Support exponential field encoding in multicast (IGMPv3 and MLDv2).

- Support attaching PSP crypto offload to containers (veth, netkit).

- Add a new IPSec Netlink message XFRM_MSG_MIGRATE_STATE that allows
migrating individual IPsec SAs independently of their policies.

The existing XFRM_MSG_MIGRATE is tightly coupled to policy+SA
migration, lacks SPI for unique SA identification, and cannot
express reqid changes or migrate Transport mode selectors.

The new interface identifies the SA via SPI and mark, supports
reqid changes, address family changes, encap removal, and uses an
atomic create+install flow under x->lock to prevent SN/IV reuse
during AEAD SA migration.

- Implement GRO/GSO support for PPPoE.

- Convert sockopt callbacks in a number of protocols to iov_iter.

Cross-tree stuff:

- Remove support for Crypto TFM cloning (unblocked after the TCP Auth
Option rework). This feature regressed performance for all crypto
API users, since it changed crypto transformation objects into
reference-counted objects.

- Add FCrypt-PCBC implementation to rxrpc and remove it from the
global crypto API as obsolete and insecure.

Wireless:

- Major rework of station bandwidth handling, fixing issues with
lower capability than AP.

- Cleanups for EMLSR spec issues (drafts differed).

- More Neighbor Awareness Networking (Wi-Fi Aware) work (multicast,
schedule improvements, multi-station etc.)

- Some Ultra High Reliability (UHR) / IEEE 802.11bn (D1.4) work
(e.g. non-primary channel access, UHR DBE support).

- Fine Timing Measurement ranging (i.e. distance measurement) APIs.

Netfilter:

- Use per-rule hash initval in nf_conncount. This avoids unnecessary
lock contention with short keys (e.g. conntrack zones) in different
namespaces.

- Various safety improvements, both in packet parsing and object
lifetimes. Notably add refcounts to conntrack timeout policy.

Deletions:

- Remove TLS + sockmap integration. TLS wants to pin user pages to
avoid a copy, and sockmap wants to write to the input stream. More
work on this integration is clearly needed, and we can't find any
users (original author admitted that they never deployed it).

- Remove support for TLS offload with TCP Offload Engine (the far
more common opportunistic offload is retained). The locking looks
unfixable (driver sleeps under TCP spin locks) and people from the
vendor that added this are AWOL.

- Remove more ATM code, trying to leave behind only what PPPoATM
needs, AAL5 and br2684 with permanent circuits.

- Remove AppleTalk. Let it join hamradio in our out of tree protocol
graveyard, I mean, repository.

- Disable 32-bit x_tables compatibility (32bit binaries on 64bit
kernel) interface in user namespaces. To be deleted completely,
soon.

- Remove 5/10 MHz support from cfg80211/mac80211.

Drivers:

- Software:
- Support DEVMEM/DMABUF Tx over NETMEM_TX_NO_DMA devices (netkit)
- bonding: add knob to strictly follow 802.3ad for link state

- New drivers:
- Alibaba Elastic Ethernet Adaptor (cloud vNIC).
- NXP NETC switch within i.MX94.

- DPLL:
- Add operational state to pins (implement in zl3073x).
- Add generic DPLL type, for daisy-chaining DPLLs (implement in ice).

- Ethernet high-speed NICs:
- Huawei (hinic3):
- enhance tc flow offload support with queue selection,
tunnels
- nVidia/Mellanox:
- avoid over-copying payload to the skb's linear part (up to
60% win for LRO on slow CPUs like ARM64 V2)
- expose more per-queue stats over the standard API
- support additional, unprivileged PFs in the DPU
configuration
- support Socket Direct (multi-PF) with switchdev offloads
- add a pool / frag allocator for DMA mapped buffers for
control objects, save memory on systems with 64kB page size
- take advantage of the ability to dynamically change RSS
table size, even when table is configured by the user
- increase the max RSS table size for even traffic
distribution

- Ethernet NICs:
- Marvell/Aquantia:
- AQC113 PTP support
- Realtek USB (r8152):
- support 10Gbit Link Speeds and Energy-Efficient Ethernet
(EEE)
- support firmware loaded (for RTL8157/RTL8159)
- support for the RTL8159
- Intel (ixgbe):
- support Energy-Efficient Ethernet (EEE) on E610 devices

- Ethernet switches:
- Airoha:
- support multiple netdevs on a single GDM block / port
- Marvell (mv88e6xxx):
- support SERDES of mv88e6321
- Microchip (ksz8/9):
- rework the driver callbacks to remove one indirection layer
- Motorcomm (yt921x):
- support port rate policing
- support TBF qdisc offload
- support ACL/flower offload
- nVidia/Mellanox:
- expose per-PG rx_discards
- Realtek:
- rtl8365mb: bridge offloading and VLAN support

- Ethernet PHYs:
- Airoha:
- support Airoha AN8801R Gigabit PHYs.
- Micrel:
- implement 3 low-loss cable tunables
- Realtek:
- support MDI swapping for RTL8226-CG
- support MDIO for RTL931x
- Qualcomm:
- at803x: Rx and Tx clock management for IPQ5018 PHY
- Motorcomm:
- support YT8522 100M RMII PHY
- set drive strength in YT8531s RGMII
- TI:
- dp83822: add optional external PHY clock

- Bluetooth:
- hci_sync: add support for HCI_LE_Set_Host_Feature [v2]
- SMP: use AES-CMAC library API
- Intel:
- support Product level reset
- support smart trigger dump
- Mediatek:
- add event filter to filter specific event
- Realtek:
- fix RTL8761B/BU broken LE extended scan

- WiFi:
- Broadcom (b43):
- new support for a 11n device
- MediaTek (mt76):
- support mt7927
- mt792x: broken usb transport detection
- mt7921: regulatory improvements
- Qualcomm (ath9k):
- GPIO interface improvements
- Qualcomm (ath12k):
- WDS support
- replace dynamic memory allocation in WMI Rx path
- thermal throttling/cooling device support
- 6 GHz incumbent interference detection
- channel 177 in 5 GHz
- Realtek (rt89):
- RTL8922AU support
- USB 3 mode switch for performance
- better monitor radiotap support
- RTL8922DE preparations"

* tag 'net-next-7.2' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1778 commits)
ipv4: fib_rule: Move fib4_rules_exit() to ->exit().
net: serialize netif_running() check in enqueue_to_backlog()
net: skmsg: preserve sg.copy across SG transforms
appletalk: move the protocol out of tree
appletalk: stop storing per-interface state in struct net_device
selftests/bpf: test that TLS crypto is rejected on a sockmap socket
selftests/bpf: drop the unused kTLS program from test_sockmap
selftests/bpf: remove sockmap + ktls tests
tls: remove dead sockmap (psock) handling from the SW path
tls: reject the combination of TLS and sockmap
atm: remove orphaned uAPI for deleted drivers, protocols and SVCs
atm: remove unused ATM PHY operations
atm: remove the unused pre_send and send_bh device operations
atm: remove the unused change_qos device operation
atm: remove SVC socket support and the signaling daemon interface
atm: remove the local ATM (NSAP) address registry
atm: remove dead SONET PHY ioctls
atm: remove the unused send_oam / push_oam callbacks
atm: remove AAL3/4 transport support
net: dsa: sja1105: fix lastused timestamp in flower stats
...

ipv4: fib_rule: Move fib4_rules_exit() to ->exit().

2026-06-16T22:42:53+00:00

syzbot reported use-after-free of net->ipv4.rules_ops. [0]

It can be reproduced with these commands:

  while true; do
  	ip netns add ns1
  	ip -n ns1 link set dev lo up
  	ip -n ns1 address add 192.0.2.1/24 dev lo
  	ip -n ns1 link add name dummy1 up type dummy
  	ip -n ns1 address add 198.51.100.1/24 dev dummy1
  	ip -n ns1 rule add ipproto tcp sport 12345 table 12345
  	ip -n ns1 fou add port 5555 ipproto 47 local 192.0.2.1 peer 198.51.100.2 peer_port 54321
  	ip netns del ns1
  done

The cited commit moved fib4_rules_exit() earlier to ->exit_rtnl(),
but the kernel socket destroyed in ->exit() could eventually reach
__fib_lookup().

I left fib4_rules_exit() in ->exit_rtnl() because fib4_rule_delete()
calls fib_unmerge(), which requires RTNL.

However, when ->delete() is called, ->configure() has already been
called, thus fib_unmerge() in ->delete() has no effect.

Let's remove fib_unmerge() in fib4_rule_delete() and move
fib4_rules_exit() to ->exit().

Many thanks to Ido Schimmel for providing the nice repro very quickly.

Note that we can make fib_rules_ops.delete() return void once
net-next opens.

[0]:
BUG: KASAN: slab-use-after-free in fib_rules_lookup+0x15e/0xeb0 net/core/fib_rules.c:321
Read of size 8 at addr ffff88804ec4c680 by task kworker/u8:21/12641

CPU: 0 UID: 0 PID: 12641 Comm: kworker/u8:21 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
Workqueue: netns cleanup_net
Call Trace:
 
 dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
 print_address_description+0x55/0x1e0 mm/kasan/report.c:378
 print_report+0x58/0x70 mm/kasan/report.c:482
 kasan_report+0x117/0x150 mm/kasan/report.c:595
 fib_rules_lookup+0x15e/0xeb0 net/core/fib_rules.c:321
 __fib_lookup+0x106/0x210 net/ipv4/fib_rules.c:96
 ip_route_output_key_hash_rcu+0x294/0x2720 net/ipv4/route.c:2811
 ip_route_output_key_hash+0x18d/0x2a0 net/ipv4/route.c:2702
 __ip_route_output_key include/net/route.h:169 [inline]
 ip_route_output_flow+0x2a/0x150 net/ipv4/route.c:2929
 ip4_datagram_release_cb+0x89d/0xbe0 net/ipv4/datagram.c:118
 release_sock+0x206/0x260 net/core/sock.c:3861
 inet_shutdown+0x2b1/0x390 net/ipv4/af_inet.c:950
 udp_tunnel_sock_release+0x6d/0x80 net/ipv4/udp_tunnel_core.c:197
 fou_release net/ipv4/fou_core.c:562 [inline]
 fou_exit_net+0x17d/0x1f0 net/ipv4/fou_core.c:1230
 ops_exit_list net/core/net_namespace.c:199 [inline]
 ops_undo_list+0x43d/0x8d0 net/core/net_namespace.c:252
 cleanup_net+0x572/0x810 net/core/net_namespace.c:702
 process_one_work kernel/workqueue.c:3314 [inline]
 process_scheduled_works+0xa8e/0x14e0 kernel/workqueue.c:3397
 worker_thread+0xa47/0xfb0 kernel/workqueue.c:3478
 kthread+0x389/0x470 kernel/kthread.c:436
 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 

Fixes: 759923cf03b0 ("ipv4: fib: Convert fib_net_exit_batch() to ->exit_rtnl().")
Reported-by: syzbot+965506b59a2de0b6905c@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/all/6a315824.b0403584.28d0ff.0000.GAE@google.com/
Signed-off-by: Kuniyuki Iwashima 
Link: https://patch.msgid.link/20260616191359.4142661-1-kuniyu@google.com
Signed-off-by: Jakub Kicinski