linux/include
Florian Westphal 207b3ebacb netfilter: nfnetlink_queue: do shared-unconfirmed check before segmentation
Ulrich reports a regression with nfqueue:

If an application did not set the 'F_GSO' capability flag and a gso
packet with an unconfirmed nf_conn entry is received all packets are
now dropped instead of queued, because the check happens after
skb_gso_segment().  In that case, we did have exclusive ownership
of the skb and its associated conntrack entry.  The elevated use
count is due to skb_clone happening via skb_gso_segment().

Move the check so that its peformed vs. the aggregated packet.

Then, annotate the individual segments except the first one so we
can do a 2nd check at reinject time.

For the normal case, where userspace does in-order reinjects, this avoids
packet drops: first reinjected segment continues traversal and confirms
entry, remaining segments observe the confirmed entry.

While at it, simplify nf_ct_drop_unconfirmed(): We only care about
unconfirmed entries with a refcnt > 1, there is no need to special-case
dying entries.

This only happens with UDP.  With TCP, the only unconfirmed packet will
be the TCP SYN, those aren't aggregated by GRO.

Next patch adds a udpgro test case to cover this scenario.

Reported-by: Ulrich Weber <ulrich.weber@gmail.com>
Fixes: 7d8dc1c7be ("netfilter: nf_queue: drop packets with cloned unconfirmed conntracks")
Signed-off-by: Florian Westphal <fw@strlen.de>
2026-02-06 13:34:55 +01:00
..
acpi ACPI: PCI: IRQ: Fix INTx GSIs signedness 2026-01-05 19:06:40 +01:00
asm-generic mm/hugetlb: fix excessive IPI broadcasts when unsharing PMD tables using mmu_gather 2026-01-20 09:34:26 -08:00
clocksource
crypto lib/crypto: sha1: Remove low-level functions from API 2026-01-27 15:47:41 -08:00
cxl
drm drm, drm/xe: Fix xe userptr in the absence of CONFIG_DEVICE_PRIVATE 2026-01-22 10:41:18 +01:00
dt-bindings Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2026-01-22 20:14:36 -08:00
hyperv mshv: add definitions for arm64 gpa intercepts 2026-01-15 07:28:58 +00:00
keys
kunit kunit: Enforce task execution in {soft,hard}irq contexts 2025-12-22 12:20:08 -08:00
kvm
linux net/mlx5: Fix 1600G link mode enum naming 2026-02-05 18:29:04 -08:00
math-emu
media
memory
misc
net netfilter: nfnetlink_queue: do shared-unconfirmed check before segmentation 2026-02-06 13:34:55 +01:00
pcmcia
ras Significant patch series in this merge are as follows: 2025-12-05 13:52:43 -08:00
rdma
rv rv: Fix compilation if !CONFIG_RV_REACTORS 2025-12-02 12:33:37 -05:00
scsi scsi: core: Fix error handler encryption support 2026-01-04 15:16:20 -05:00
soc This pull request is entirely SoC clk drivers, not for lack of trying to modify 2025-12-08 09:38:52 +09:00
sound ALSA: pcm: Improve the fix for race of buffer access at PCM OSS layer 2026-01-08 08:07:54 +01:00
target
trace trace: mptcp: add mptcp_rcvbuf_grow tracepoint 2026-02-04 18:45:09 -08:00
uapi Some more changes, including pulls from drivers: 2026-02-04 20:31:05 -08:00
ufs
vdso
video
xen
Kbuild