linux-toradex.git/include/net, branch v7.0-rc3

libeth, idpf: use truesize as XDP RxQ info frag_size

2026-03-05T16:02:05+00:00

The only user of frag_size field in XDP RxQ info is
bpf_xdp_frags_increase_tail(). It clearly expects whole buffer size instead
of DMA write size. Different assumptions in idpf driver configuration lead
to negative tailroom.

To make it worse, buffer sizes are not actually uniform in idpf when
splitq is enabled, as there are several buffer queues, so rxq->rx_buf_size
is meaningless in this case.

Use truesize of the first bufq in AF_XDP ZC, as there is only one. Disable
growing tail for regular splitq.

Fixes: ac8a861f632e ("idpf: prepare structures to support XDP")
Reviewed-by: Aleksandr Loktionov 
Signed-off-by: Larysa Zaremba 
Link: https://patch.msgid.link/20260305111253.2317394-8-larysa.zaremba@intel.com
Signed-off-by: Jakub Kicinski

xsk: introduce helper to determine rxq->frag_size

2026-03-05T16:02:03+00:00

rxq->frag_size is basically a step between consecutive strictly aligned
frames. In ZC mode, chunk size fits exactly, but if chunks are unaligned,
there is no safe way to determine accessible space to grow tailroom.

Report frag_size to be zero, if chunks are unaligned, chunk_size otherwise.

Fixes: 24ea50127ecf ("xsk: support mbuf on ZC RX")
Reviewed-by: Aleksandr Loktionov 
Signed-off-by: Larysa Zaremba 
Link: https://patch.msgid.link/20260305111253.2317394-3-larysa.zaremba@intel.com
Signed-off-by: Jakub Kicinski

net/sched: act_ife: Fix metalist update behavior

2026-03-05T15:54:08+00:00

Whenever an ife action replace changes the metalist, instead of
replacing the old data on the metalist, the current ife code is appending
the new metadata. Aside from being innapropriate behavior, this may lead
to an unbounded addition of metadata to the metalist which might cause an
out of bounds error when running the encode op:

[  138.423369][    C1] ==================================================================
[  138.424317][    C1] BUG: KASAN: slab-out-of-bounds in ife_tlv_meta_encode (net/ife/ife.c:168)
[  138.424906][    C1] Write of size 4 at addr ffff8880077f4ffe by task ife_out_out_bou/255
[  138.425778][    C1] CPU: 1 UID: 0 PID: 255 Comm: ife_out_out_bou Not tainted 7.0.0-rc1-00169-gfbdfa8da05b6 #624 PREEMPT(full)
[  138.425795][    C1] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[  138.425800][    C1] Call Trace:
[  138.425804][    C1]  
[  138.425808][    C1]  dump_stack_lvl (lib/dump_stack.c:122)
[  138.425828][    C1]  print_report (mm/kasan/report.c:379 mm/kasan/report.c:482)
[  138.425839][    C1]  ? srso_alias_return_thunk (arch/x86/lib/retpoline.S:221)
[  138.425844][    C1]  ? __virt_addr_valid (./arch/x86/include/asm/preempt.h:95 (discriminator 1) ./include/linux/rcupdate.h:975 (discriminator 1) ./include/linux/mmzone.h:2207 (discriminator 1) arch/x86/mm/physaddr.c:54 (discriminator 1))
[  138.425853][    C1]  ? ife_tlv_meta_encode (net/ife/ife.c:168)
[  138.425859][    C1]  kasan_report (mm/kasan/report.c:221 mm/kasan/report.c:597)
[  138.425868][    C1]  ? ife_tlv_meta_encode (net/ife/ife.c:168)
[  138.425878][    C1]  kasan_check_range (mm/kasan/generic.c:186 (discriminator 1) mm/kasan/generic.c:200 (discriminator 1))
[  138.425884][    C1]  __asan_memset (mm/kasan/shadow.c:84 (discriminator 2))
[  138.425889][    C1]  ife_tlv_meta_encode (net/ife/ife.c:168)
[  138.425893][    C1]  ? ife_tlv_meta_encode (net/ife/ife.c:171)
[  138.425898][    C1]  ? srso_alias_return_thunk (arch/x86/lib/retpoline.S:221)
[  138.425903][    C1]  ife_encode_meta_u16 (net/sched/act_ife.c:57)
[  138.425910][    C1]  ? __pfx_do_raw_spin_lock (kernel/locking/spinlock_debug.c:114)
[  138.425916][    C1]  ? __asan_memcpy (mm/kasan/shadow.c:105 (discriminator 3))
[  138.425921][    C1]  ? __pfx_ife_encode_meta_u16 (net/sched/act_ife.c:45)
[  138.425927][    C1]  ? srso_alias_return_thunk (arch/x86/lib/retpoline.S:221)
[  138.425931][    C1]  tcf_ife_act (net/sched/act_ife.c:847 net/sched/act_ife.c:879)

To solve this issue, fix the replace behavior by adding the metalist to
the ife rcu data structure.

Fixes: aa9fd9a325d51 ("sched: act: ife: update parameters via rcu handling")
Reported-by: Ruitong Liu 
Tested-by: Ruitong Liu 
Co-developed-by: Victor Nogueira 
Signed-off-by: Victor Nogueira 
Signed-off-by: Jamal Hadi Salim 
Link: https://patch.msgid.link/20260304140603.76500-1-jhs@mojatatu.com
Signed-off-by: Jakub Kicinski

netfilter: nft_set_pipapo: split gc into unlink and reclaim phase

2026-03-05T12:22:37+00:00

Yiming Qian reports Use-after-free in the pipapo set type:
  Under a large number of expired elements, commit-time GC can run for a very
  long time in a non-preemptible context, triggering soft lockup warnings and
  RCU stall reports (local denial of service).

We must split GC in an unlink and a reclaim phase.

We cannot queue elements for freeing until pointers have been swapped.
Expired elements are still exposed to both the packet path and userspace
dumpers via the live copy of the data structure.

call_rcu() does not protect us: dump operations or element lookups starting
after call_rcu has fired can still observe the free'd element, unless the
commit phase has made enough progress to swap the clone and live pointers
before any new reader has picked up the old version.

This a similar approach as done recently for the rbtree backend in commit
35f83a75529a ("netfilter: nft_set_rbtree: don't gc elements on insert").

Fixes: 3c4287f62044 ("nf_tables: Add set type for arbitrary concatenation of ranges")
Reported-by: Yiming Qian 
Signed-off-by: Florian Westphal

netfilter: nf_tables: clone set on flush only

2026-03-05T12:22:37+00:00

Syzbot with fault injection triggered a failing memory allocation with
GFP_KERNEL which results in a WARN splat:

iter.err
WARNING: net/netfilter/nf_tables_api.c:845 at nft_map_deactivate+0x34e/0x3c0 net/netfilter/nf_tables_api.c:845, CPU#0: syz.0.17/5992
Modules linked in:
CPU: 0 UID: 0 PID: 5992 Comm: syz.0.17 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
RIP: 0010:nft_map_deactivate+0x34e/0x3c0 net/netfilter/nf_tables_api.c:845
Code: 8b 05 86 5a 4e 09 48 3b 84 24 a0 00 00 00 75 62 48 8d 65 d8 5b 41 5c 41 5d 41 5e 41 5f 5d c3 cc cc cc cc cc e8 63 6d fa f7 90 <0f> 0b 90 43
+80 7c 35 00 00 0f 85 23 fe ff ff e9 26 fe ff ff 89 d9
RSP: 0018:ffffc900045af780 EFLAGS: 00010293
RAX: ffffffff89ca45bd RBX: 00000000fffffff4 RCX: ffff888028111e40
RDX: 0000000000000000 RSI: 00000000fffffff4 RDI: 0000000000000000
RBP: ffffc900045af870 R08: 0000000000400dc0 R09: 00000000ffffffff
R10: dffffc0000000000 R11: fffffbfff1d141db R12: ffffc900045af7e0
R13: 1ffff920008b5f24 R14: dffffc0000000000 R15: ffffc900045af920
FS:  000055557a6a5500(0000) GS:ffff888125496000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fb5ea271fc0 CR3: 000000003269e000 CR4: 00000000003526f0
Call Trace:
 
 __nft_release_table+0xceb/0x11f0 net/netfilter/nf_tables_api.c:12115
 nft_rcv_nl_event+0xc25/0xdb0 net/netfilter/nf_tables_api.c:12187
 notifier_call_chain+0x19d/0x3a0 kernel/notifier.c:85
 blocking_notifier_call_chain+0x6a/0x90 kernel/notifier.c:380
 netlink_release+0x123b/0x1ad0 net/netlink/af_netlink.c:761
 __sock_release net/socket.c:662 [inline]
 sock_close+0xc3/0x240 net/socket.c:1455

Restrict set clone to the flush set command in the preparation phase.
Add NFT_ITER_UPDATE_CLONE and use it for this purpose, update the rbtree
and pipapo backends to only clone the set when this iteration type is
used.

As for the existing NFT_ITER_UPDATE type, update the pipapo backend to
use the existing set clone if available, otherwise use the existing set
representation. After this update, there is no need to clone a set that
is being deleted, this includes bound anonymous set.

An alternative approach to NFT_ITER_UPDATE_CLONE is to add a .clone
interface and call it from the flush set path.

Reported-by: syzbot+4924a0edc148e8b4b342@syzkaller.appspotmail.com
Fixes: 3f1d886cc7c3 ("netfilter: nft_set_pipapo: move cloning of match info to insert/removal path")
Signed-off-by: Pablo Neira Ayuso 
Signed-off-by: Florian Westphal

tcp: secure_seq: add back ports to TS offset

2026-03-05T01:44:35+00:00

This reverts 28ee1b746f49 ("secure_seq: downgrade to per-host timestamp offsets")

tcp_tw_recycle went away in 2017.

Zhouyan Deng reported off-path TCP source port leakage via
SYN cookie side-channel that can be fixed in multiple ways.

One of them is to bring back TCP ports in TS offset randomization.

As a bonus, we perform a single siphash() computation
to provide both an ISN and a TS offset.

Fixes: 28ee1b746f49 ("secure_seq: downgrade to per-host timestamp offsets")
Reported-by: Zhouyan Deng 
Signed-off-by: Eric Dumazet 
Reviewed-by: Kuniyuki Iwashima 
Acked-by: Florian Westphal 
Link: https://patch.msgid.link/20260302205527.1982836-1-edumazet@google.com
Signed-off-by: Jakub Kicinski

net: sched: avoid qdisc_reset_all_tx_gt() vs dequeue race for lockless qdiscs

2026-03-05T01:43:45+00:00

When shrinking the number of real tx queues,
netif_set_real_num_tx_queues() calls qdisc_reset_all_tx_gt() to flush
qdiscs for queues which will no longer be used.

qdisc_reset_all_tx_gt() currently serializes qdisc_reset() with
qdisc_lock(). However, for lockless qdiscs, the dequeue path is
serialized by qdisc_run_begin/end() using qdisc->seqlock instead, so
qdisc_reset() can run concurrently with __qdisc_run() and free skbs
while they are still being dequeued, leading to UAF.

This can easily be reproduced on e.g. virtio-net by imposing heavy
traffic while frequently changing the number of queue pairs:

  iperf3 -ub0 -c $peer -t 0 &
  while :; do
    ethtool -L eth0 combined 1
    ethtool -L eth0 combined 2
  done

With KASAN enabled, this leads to reports like:

  BUG: KASAN: slab-use-after-free in __qdisc_run+0x133f/0x1760
  ...
  Call Trace:
   
   ...
   __qdisc_run+0x133f/0x1760
   __dev_queue_xmit+0x248f/0x3550
   ip_finish_output2+0xa42/0x2110
   ip_output+0x1a7/0x410
   ip_send_skb+0x2e6/0x480
   udp_send_skb+0xb0a/0x1590
   udp_sendmsg+0x13c9/0x1fc0
   ...
   

  Allocated by task 1270 on cpu 5 at 44.558414s:
   ...
   alloc_skb_with_frags+0x84/0x7c0
   sock_alloc_send_pskb+0x69a/0x830
   __ip_append_data+0x1b86/0x48c0
   ip_make_skb+0x1e8/0x2b0
   udp_sendmsg+0x13a6/0x1fc0
   ...

  Freed by task 1306 on cpu 3 at 44.558445s:
   ...
   kmem_cache_free+0x117/0x5e0
   pfifo_fast_reset+0x14d/0x580
   qdisc_reset+0x9e/0x5f0
   netif_set_real_num_tx_queues+0x303/0x840
   virtnet_set_channels+0x1bf/0x260 [virtio_net]
   ethnl_set_channels+0x684/0xae0
   ethnl_default_set_doit+0x31a/0x890
   ...

Serialize qdisc_reset_all_tx_gt() against the lockless dequeue path by
taking qdisc->seqlock for TCQ_F_NOLOCK qdiscs, matching the
serialization model already used by dev_reset_queue().

Additionally clear QDISC_STATE_NON_EMPTY after reset so the qdisc state
reflects an empty queue, avoiding needless re-scheduling.

Fixes: 6b3ba9146fe6 ("net: sched: allow qdiscs to handle locking")
Signed-off-by: Koichiro Den 
Link: https://patch.msgid.link/20260228145307.3955532-1-den@valinux.co.jp
Signed-off-by: Jakub Kicinski

net: ipv4: fix ARM64 alignment fault in multipath hash seed

2026-03-04T01:20:37+00:00

`struct sysctl_fib_multipath_hash_seed` contains two u32 fields
(user_seed and mp_seed), making it an 8-byte structure with a 4-byte
alignment requirement.

In `fib_multipath_hash_from_keys()`, the code evaluates the entire
struct atomically via `READ_ONCE()`:

    mp_seed = READ_ONCE(net->ipv4.sysctl_fib_multipath_hash_seed).mp_seed;

While this silently works on GCC by falling back to unaligned regular
loads which the ARM64 kernel tolerates, it causes a fatal kernel panic
when compiled with Clang and LTO enabled.

Commit e35123d83ee3 ("arm64: lto: Strengthen READ_ONCE() to acquire
when CONFIG_LTO=y") strengthens `READ_ONCE()` to use Load-Acquire
instructions (`ldar` / `ldapr`) to prevent compiler reordering bugs
under Clang LTO. Since the macro evaluates the full 8-byte struct,
Clang emits a 64-bit `ldar` instruction. ARM64 architecture strictly
requires `ldar` to be naturally aligned, thus executing it on a 4-byte
aligned address triggers a strict Alignment Fault (FSC = 0x21).

Fix the read side by moving the `READ_ONCE()` directly to the `u32`
member, which emits a safe 32-bit `ldar Wn`.

Furthermore, Eric Dumazet pointed out that `WRITE_ONCE()` on the entire
struct in `proc_fib_multipath_hash_set_seed()` is also flawed. Analysis
shows that Clang splits this 8-byte write into two separate 32-bit
`str` instructions. While this avoids an alignment fault, it destroys
atomicity and exposes a tear-write vulnerability. Fix this by
explicitly splitting the write into two 32-bit `WRITE_ONCE()`
operations.

Finally, add the missing `READ_ONCE()` when reading `user_seed` in
`proc_fib_multipath_hash_seed()` to ensure proper pairing and
concurrency safety.

Fixes: 4ee2a8cace3f ("net: ipv4: Add a sysctl to set multipath hash seed")
Signed-off-by: Yung Chih Su 
Reviewed-by: Eric Dumazet 
Link: https://patch.msgid.link/20260302060247.7066-1-yuuchihsu@gmail.com
Signed-off-by: Jakub Kicinski

bpf/bonding: reject vlan+srcmac xmit_hash_policy change when XDP is loaded

2026-03-03T09:47:37+00:00

bond_option_mode_set() already rejects mode changes that would make a
loaded XDP program incompatible via bond_xdp_check().  However,
bond_option_xmit_hash_policy_set() has no such guard.

For 802.3ad and balance-xor modes, bond_xdp_check() returns false when
xmit_hash_policy is vlan+srcmac, because the 802.1q payload is usually
absent due to hardware offload.  This means a user can:

1. Attach a native XDP program to a bond in 802.3ad/balance-xor mode
   with a compatible xmit_hash_policy (e.g. layer2+3).
2. Change xmit_hash_policy to vlan+srcmac while XDP remains loaded.

This leaves bond->xdp_prog set but bond_xdp_check() now returning false
for the same device.  When the bond is later destroyed, dev_xdp_uninstall()
calls bond_xdp_set(dev, NULL, NULL) to remove the program, which hits
the bond_xdp_check() guard and returns -EOPNOTSUPP, triggering:

WARN_ON(dev_xdp_install(dev, mode, bpf_op, NULL, 0, NULL))

Fix this by rejecting xmit_hash_policy changes to vlan+srcmac when an
XDP program is loaded on a bond in 802.3ad or balance-xor mode.

commit 39a0876d595b ("net, bonding: Disallow vlan+srcmac with XDP")
introduced bond_xdp_check() which returns false for 802.3ad/balance-xor
modes when xmit_hash_policy is vlan+srcmac.  The check was wired into
bond_xdp_set() to reject XDP attachment with an incompatible policy, but
the symmetric path -- preventing xmit_hash_policy from being changed to an
incompatible value after XDP is already loaded -- was left unguarded in
bond_option_xmit_hash_policy_set().

Note:
commit 094ee6017ea0 ("bonding: check xdp prog when set bond mode")
later added a similar guard to bond_option_mode_set(), but
bond_option_xmit_hash_policy_set() remained unprotected.

Reported-by: syzbot+5a287bcdc08104bc3132@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/all/6995aff6.050a0220.2eeac1.014e.GAE@google.com/T/
Fixes: 39a0876d595b ("net, bonding: Disallow vlan+srcmac with XDP")
Signed-off-by: Jiayuan Chen 
Link: https://patch.msgid.link/20260226080306.98766-2-jiayuan.chen@linux.dev
Signed-off-by: Paolo Abeni

xsk: Fix fragment node deletion to prevent buffer leak

2026-02-28T16:55:11+00:00

After commit b692bf9a7543 ("xsk: Get rid of xdp_buff_xsk::xskb_list_node"),
the list_node field is reused for both the xskb pool list and the buffer
free list, this causes a buffer leak as described below.

xp_free() checks if a buffer is already on the free list using
list_empty(&xskb->list_node). When list_del() is used to remove a node
from the xskb pool list, it doesn't reinitialize the node pointers.
This means list_empty() will return false even after the node has been
removed, causing xp_free() to incorrectly skip adding the buffer to the
free list.

Fix this by using list_del_init() instead of list_del() in all fragment
handling paths, this ensures the list node is reinitialized after removal,
allowing the list_empty() to work correctly.

Fixes: b692bf9a7543 ("xsk: Get rid of xdp_buff_xsk::xskb_list_node")
Acked-by: Maciej Fijalkowski 
Signed-off-by: Nikhil P. Rao 
Link: https://patch.msgid.link/20260225000456.107806-2-nikhil.rao@amd.com
Signed-off-by: Jakub Kicinski