Some DSA tagging protocols change the EtherType field in the MAC header
e.g. DSA_TAG_PROTO_(DSA/EDSA/BRCM/MTK/RTL4C_A/SJA1105). On TX these tagged
frames are ignored by the checksum offload engine and IP header checker of
some stmmac cores.
On RX, the stmmac driver wrongly assumes that checksums have been computed
for these tagged packets, and sets CHECKSUM_UNNECESSARY.
Add an additional check in the stmmac TX and RX hotpaths so that COE is
deactivated for packets with ethertypes that will not trigger the COE and
IP header checks.
Fixes: 6b2c6e4a938f ("net: stmmac: propagate feature flags to vlan")
Cc: <stable(a)vger.kernel.org>
Reported-by: Richard Tresidder <rtresidd(a)electromag.com.au>
Link: https://lore.kernel.org/netdev/e5c6c75f-2dfa-4e50-a1fb-6bf4cdb617c2@electro…
Reported-by: Romain Gantois <romain.gantois(a)bootlin.com>
Link: https://lore.kernel.org/netdev/c57283ed-6b9b-b0e6-ee12-5655c1c54495@bootlin…
Reviewed-by: Vladimir Oltean <vladimir.oltean(a)nxp.com>
Reviewed-by: Linus Walleij <linus.walleij(a)linaro.org>
Signed-off-by: Romain Gantois <romain.gantois(a)bootlin.com>
---
Hello everyone,
This is the fifth version of my proposed fix for the stmmac checksum
offloading issue that has recently been reported.
significant changes in v4:
- Removed "inline" from declaration of stmmac_has_ip_ethertype
significant changes in v3:
- Use __vlan_get_protocol to make sure that 8021Q-encapsulated
traffic is checked correctly.
significant changes in v2:
- Replaced the stmmac_link_up-based fix with an ethertype check in the TX
and RX hotpaths.
The Checksum Offloading Engine of some stmmac cores (e.g. DWMAC1000)
computes an incorrect checksum when presented with DSA-tagged packets. This
causes all TCP/UDP transfers to break when the stmmac device is connected
to the CPU port of a DSA switch.
I ran some tests using different tagging protocols with DSA_LOOP, and all
of the protocols that set a custom ethertype field in the MAC header caused
the checksum offload engine to ignore the tagged packets. On TX, this
caused packets to egress with incorrect checksums. On RX, these packets
were similarly ignored by the COE, yet the stmmac driver set
CHECKSUM_UNNECESSARY, wrongly assuming that their checksums had been
verified in hardware.
Version 2 of this patch series fixes this issue by checking ethertype
fields in both the TX and RX hotpaths of the stmmac driver. On TX, if a
non-IP ethertype is detected, the packet is checksummed in software. On
RX, the same condition causes stmmac to avoid setting CHECKSUM_UNNECESSARY.
To measure the performance degradation to the TX/RX hotpaths, I did some
iperf3 runs with 512-byte unfragmented UDP packets.
measured degradation on TX: -466 pps (-0.2%) on RX: -338 pps (-1.2%)
original performances on TX: 22kpps on RX: 27kpps
The performance hit on the RX path can be partly explained by the fact that
the stmmac driver doesn't set CHECKSUM_UNNECESSARY anymore.
The TX performance degradation observed in v2 seems to have improved.
It's not entirely clear to me why that is.
Best Regards,
Romain
Romain Gantois (1):
net: stmmac: Prevent DSA tags from breaking COE
.../net/ethernet/stmicro/stmmac/stmmac_main.c | 23 ++++++++++++++++---
1 file changed, 20 insertions(+), 3 deletions(-)
--
2.43.0
---
Changes in v5:
- Added missing "net" tag to subject of patch series
- Link to v4: https://lore.kernel.org/r/20240109-prevent_dsa_tags-v4-1-f888771fa2f6@bootl…
---
drivers/net/ethernet/stmicro/stmmac/stmmac_main.c | 29 ++++++++++++++++++++---
1 file changed, 26 insertions(+), 3 deletions(-)
diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
index 37e64283f910..b30dba06dbd1 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
@@ -4371,6 +4371,25 @@ static netdev_tx_t stmmac_tso_xmit(struct sk_buff *skb, struct net_device *dev)
return NETDEV_TX_OK;
}
+/**
+ * stmmac_has_ip_ethertype() - Check if packet has IP ethertype
+ * @skb: socket buffer to check
+ *
+ * Check if a packet has an ethertype that will trigger the IP header checks
+ * and IP/TCP checksum engine of the stmmac core.
+ *
+ * Return: true if the ethertype can trigger the checksum engine, false otherwise
+ */
+static bool stmmac_has_ip_ethertype(struct sk_buff *skb)
+{
+ int depth = 0;
+ __be16 proto;
+
+ proto = __vlan_get_protocol(skb, eth_header_parse_protocol(skb), &depth);
+
+ return (depth <= ETH_HLEN) && (proto == htons(ETH_P_IP) || proto == htons(ETH_P_IPV6));
+}
+
/**
* stmmac_xmit - Tx entry point of the driver
* @skb : the socket buffer
@@ -4435,9 +4454,13 @@ static netdev_tx_t stmmac_xmit(struct sk_buff *skb, struct net_device *dev)
/* DWMAC IPs can be synthesized to support tx coe only for a few tx
* queues. In that case, checksum offloading for those queues that don't
* support tx coe needs to fallback to software checksum calculation.
+ *
+ * Packets that won't trigger the COE e.g. most DSA-tagged packets will
+ * also have to be checksummed in software.
*/
if (csum_insertion &&
- priv->plat->tx_queues_cfg[queue].coe_unsupported) {
+ (priv->plat->tx_queues_cfg[queue].coe_unsupported ||
+ !stmmac_has_ip_ethertype(skb))) {
if (unlikely(skb_checksum_help(skb)))
goto dma_map_err;
csum_insertion = !csum_insertion;
@@ -4997,7 +5020,7 @@ static void stmmac_dispatch_skb_zc(struct stmmac_priv *priv, u32 queue,
stmmac_rx_vlan(priv->dev, skb);
skb->protocol = eth_type_trans(skb, priv->dev);
- if (unlikely(!coe))
+ if (unlikely(!coe) || !stmmac_has_ip_ethertype(skb))
skb_checksum_none_assert(skb);
else
skb->ip_summed = CHECKSUM_UNNECESSARY;
@@ -5513,7 +5536,7 @@ static int stmmac_rx(struct stmmac_priv *priv, int limit, u32 queue)
stmmac_rx_vlan(priv->dev, skb);
skb->protocol = eth_type_trans(skb, priv->dev);
- if (unlikely(!coe))
+ if (unlikely(!coe) || !stmmac_has_ip_ethertype(skb))
skb_checksum_none_assert(skb);
else
skb->ip_summed = CHECKSUM_UNNECESSARY;
---
base-commit: ac631873c9e7a50d2a8de457cfc4b9f86666403e
change-id: 20240108-prevent_dsa_tags-7bb0def0db81
Best regards,
--
Romain Gantois <romain.gantois(a)bootlin.com>
Il 16/01/24 11:52, Sasha Levin ha scritto:
> This is a note to let you know that I've just added the patch titled
>
> ASoC: SOF: mediatek: mt8186: Add Google Steelix topology compatible
>
> to the 6.1-stable tree which can be found at:
> http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=sum…
>
> The filename of the patch is:
> asoc-sof-mediatek-mt8186-add-google-steelix-topology.patch
> and it can be found in the queue-6.1 subdirectory.
>
> If you, or anyone else, feels it should not be added to the stable tree,
> please let <stable(a)vger.kernel.org> know about it.
>
This commit got reverted afterwards, please don't backport.
Ref.:
https://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound.git/commit/?i…
Thanks,
Angelo
>
>
> commit 152629176282853223e1768c312539ee0d847384
> Author: AngeloGioacchino Del Regno <angelogioacchino.delregno(a)collabora.com>
> Date: Thu Nov 23 09:44:54 2023 +0100
>
> ASoC: SOF: mediatek: mt8186: Add Google Steelix topology compatible
>
> [ Upstream commit 505c83212da5bfca95109421b8f5d9f8c6cdfef2 ]
>
> Add the machine compatible and topology filename for the Google Steelix
> MT8186 Chromebook to load the correct SOF topology file.
>
> Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno(a)collabora.com>
> Link: https://lore.kernel.org/r/20231123084454.20471-1-angelogioacchino.delregno@…
> Signed-off-by: Mark Brown <broonie(a)kernel.org>
> Signed-off-by: Sasha Levin <sashal(a)kernel.org>
>
> diff --git a/sound/soc/sof/mediatek/mt8186/mt8186.c b/sound/soc/sof/mediatek/mt8186/mt8186.c
> index 181189e00e02..76ce90e1f103 100644
> --- a/sound/soc/sof/mediatek/mt8186/mt8186.c
> +++ b/sound/soc/sof/mediatek/mt8186/mt8186.c
> @@ -596,6 +596,9 @@ static struct snd_sof_dsp_ops sof_mt8186_ops = {
>
> static struct snd_sof_of_mach sof_mt8186_machs[] = {
> {
> + .compatible = "google,steelix",
> + .sof_tplg_filename = "sof-mt8186-google-steelix.tplg"
> + }, {
> .compatible = "mediatek,mt8186",
> .sof_tplg_filename = "sof-mt8186.tplg",
> },
In stable linux (4.19~5.15), if “CONFIG_BPF_SYSCALL=y” is set,
the .config generated by Kconfig does not set
“CONFIG_BPF_JIT_ALWAYS_ON” and “CONFIG_BPF_UNPRIV_DEFAULT_OFF”.
If the kernel is compiled with such .config, a normal user
without any capabilities at all can load eBPF programs
(SOCKET_FILTER type), and uses the interpreter.
Due to the threat of side-channel attacks and inextirpable
mistakes in the verifier, this is considered insecure.
We have report this issue to maintainers of architectures.
RISCV and s390 maintainers have confirmed and advise us to
patch the Kconfig so that all architectures can be fixed.
So this patch add "default y" to these config entries.
On the other hand, we found that such configs facilitate kernel
bug exploitation. Specifically, an attacker can leverage existing
CVEs to corrupt eBPF prog-array map, hijacking a bpf_prog pointer
(ptrs[xx]) to point to a forged BPF program. In this way, arbitrary
bytecode execution can be achieved, we have proved this concept with
various CVEs(e.g. CVE-2018-18445). Such an attack enhances the
exploitability of CVEs, and is more dangerous than side-channel
threats.
Signed-off-by: liboti <hoshimi10mang(a)163.com>
---
kernel/bpf/Kconfig | 91 ++++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 91 insertions(+)
create mode 100644 kernel/bpf/Kconfig
diff --git a/kernel/bpf/Kconfig b/kernel/bpf/Kconfig
new file mode 100644
index 0000000..8abdc0d
--- /dev/null
+++ b/kernel/bpf/Kconfig
@@ -0,0 +1,91 @@
+# SPDX-License-Identifier: GPL-2.0-only
+
+# BPF interpreter that, for example, classic socket filters depend on.
+config BPF
+ bool
+
+# Used by archs to tell that they support BPF JIT compiler plus which
+# flavour. Only one of the two can be selected for a specific arch since
+# eBPF JIT supersedes the cBPF JIT.
+
+# Classic BPF JIT (cBPF)
+config HAVE_CBPF_JIT
+ bool
+
+# Extended BPF JIT (eBPF)
+config HAVE_EBPF_JIT
+ bool
+
+# Used by archs to tell that they want the BPF JIT compiler enabled by
+# default for kernels that were compiled with BPF JIT support.
+config ARCH_WANT_DEFAULT_BPF_JIT
+ bool
+
+menu "BPF subsystem"
+
+config BPF_SYSCALL
+ bool "Enable bpf() system call"
+ select BPF
+ select IRQ_WORK
+ select TASKS_TRACE_RCU
+ select BINARY_PRINTF
+ select NET_SOCK_MSG if NET
+ default n
+ help
+ Enable the bpf() system call that allows to manipulate BPF programs
+ and maps via file descriptors.
+
+config BPF_JIT
+ bool "Enable BPF Just In Time compiler"
+ depends on BPF
+ depends on HAVE_CBPF_JIT || HAVE_EBPF_JIT
+ depends on MODULES
+ help
+ BPF programs are normally handled by a BPF interpreter. This option
+ allows the kernel to generate native code when a program is loaded
+ into the kernel. This will significantly speed-up processing of BPF
+ programs.
+
+ Note, an admin should enable this feature changing:
+ /proc/sys/net/core/bpf_jit_enable
+ /proc/sys/net/core/bpf_jit_harden (optional)
+ /proc/sys/net/core/bpf_jit_kallsyms (optional)
+
+config BPF_JIT_ALWAYS_ON
+ bool "Permanently enable BPF JIT and remove BPF interpreter"
+ depends on BPF_SYSCALL && HAVE_EBPF_JIT && BPF_JIT
+ default y
+ help
+ Enables BPF JIT and removes BPF interpreter to avoid speculative
+ execution of BPF instructions by the interpreter.
+
+config BPF_JIT_DEFAULT_ON
+ def_bool ARCH_WANT_DEFAULT_BPF_JIT || BPF_JIT_ALWAYS_ON
+ depends on HAVE_EBPF_JIT && BPF_JIT
+
+config BPF_UNPRIV_DEFAULT_OFF
+ bool "Disable unprivileged BPF by default"
+ depends on BPF_SYSCALL
+ default y
+ help
+ Disables unprivileged BPF by default by setting the corresponding
+ /proc/sys/kernel/unprivileged_bpf_disabled knob to 2. An admin can
+ still reenable it by setting it to 0 later on, or permanently
+ disable it by setting it to 1 (from which no other transition to
+ 0 is possible anymore).
+
+source "kernel/bpf/preload/Kconfig"
+
+config BPF_LSM
+ bool "Enable BPF LSM Instrumentation"
+ depends on BPF_EVENTS
+ depends on BPF_SYSCALL
+ depends on SECURITY
+ depends on BPF_JIT
+ help
+ Enables instrumentation of the security hooks with BPF programs for
+ implementing dynamic MAC and Audit Policies.
+
+ If you are unsure how to answer this question, answer N.
+
+endmenu # "BPF subsystem"
--
2.34.1
The current UCM configuration sets the speaker PA volume to 15 dB when
enabling the speakers but this does not prevent the user from increasing
the volume further.
Limit the PA volume to 15 dB in the machine driver to reduce the risk of
speaker damage until we have active speaker protection in place.
Note that this will probably need to be generalised using
machine-specific limits, but a common limit should do for now.
Cc: stable(a)vger.kernel.org # 6.5
Signed-off-by: Johan Hovold <johan+linaro(a)kernel.org>
---
sound/soc/qcom/sc8280xp.c | 8 +++++---
1 file changed, 5 insertions(+), 3 deletions(-)
diff --git a/sound/soc/qcom/sc8280xp.c b/sound/soc/qcom/sc8280xp.c
index ed4bb551bfbb..aa43903421f5 100644
--- a/sound/soc/qcom/sc8280xp.c
+++ b/sound/soc/qcom/sc8280xp.c
@@ -32,12 +32,14 @@ static int sc8280xp_snd_init(struct snd_soc_pcm_runtime *rtd)
case WSA_CODEC_DMA_RX_0:
case WSA_CODEC_DMA_RX_1:
/*
- * set limit of 0dB on Digital Volume for Speakers,
- * this can prevent damage of speakers to some extent without
- * active speaker protection
+ * Set limit of 0 dB on Digital Volume and 15 dB on PA Volume
+ * to reduce the risk of speaker damage until we have active
+ * speaker protection in place.
*/
snd_soc_limit_volume(card, "WSA_RX0 Digital Volume", 84);
snd_soc_limit_volume(card, "WSA_RX1 Digital Volume", 84);
+ snd_soc_limit_volume(card, "SpkrLeft PA Volume", 12);
+ snd_soc_limit_volume(card, "SpkrRight PA Volume", 12);
break;
default:
break;
--
2.41.0
From: Rui Zhang <zr.zhang(a)vivo.com>
[ Upstream commit 7993d3a9c34f609c02171e115fd12c10e2105ff4 ]
The use_count of a regulator should only be incremented when the
enable_count changes from 0 to 1. Similarly, the use_count should
only be decremented when the enable_count changes from 1 to 0.
In the previous implementation, use_count was sometimes decremented
to 0 when some consumer called unbalanced disable,
leading to unexpected disable even the regulator is enabled by
other consumers. With this change, the use_count accurately reflects
the number of users which the regulator is enabled.
This should make things more robust in the case where a consumer does
leak references.
Signed-off-by: Rui Zhang <zr.zhang(a)vivo.com>
Link: https://lore.kernel.org/r/20231103074231.8031-1-zr.zhang@vivo.com
Signed-off-by: Mark Brown <broonie(a)kernel.org>
Signed-off-by: Sasha Levin <sashal(a)kernel.org>
---
drivers/regulator/core.c | 56 +++++++++++++++++++++-------------------
1 file changed, 30 insertions(+), 26 deletions(-)
diff --git a/drivers/regulator/core.c b/drivers/regulator/core.c
index 87d0cd6f49ca..894915892eaf 100644
--- a/drivers/regulator/core.c
+++ b/drivers/regulator/core.c
@@ -2658,7 +2658,8 @@ static int _regulator_enable(struct regulator *regulator)
/* Fallthrough on positive return values - already enabled */
}
- rdev->use_count++;
+ if (regulator->enable_count == 1)
+ rdev->use_count++;
return 0;
@@ -2736,37 +2737,40 @@ static int _regulator_disable(struct regulator *regulator)
lockdep_assert_held_once(&rdev->mutex.base);
- if (WARN(rdev->use_count <= 0,
+ if (WARN(regulator->enable_count == 0,
"unbalanced disables for %s\n", rdev_get_name(rdev)))
return -EIO;
- /* are we the last user and permitted to disable ? */
- if (rdev->use_count == 1 &&
- (rdev->constraints && !rdev->constraints->always_on)) {
-
- /* we are last user */
- if (regulator_ops_is_valid(rdev, REGULATOR_CHANGE_STATUS)) {
- ret = _notifier_call_chain(rdev,
- REGULATOR_EVENT_PRE_DISABLE,
- NULL);
- if (ret & NOTIFY_STOP_MASK)
- return -EINVAL;
-
- ret = _regulator_do_disable(rdev);
- if (ret < 0) {
- rdev_err(rdev, "failed to disable\n");
- _notifier_call_chain(rdev,
- REGULATOR_EVENT_ABORT_DISABLE,
+ if (regulator->enable_count == 1) {
+ /* disabling last enable_count from this regulator */
+ /* are we the last user and permitted to disable ? */
+ if (rdev->use_count == 1 &&
+ (rdev->constraints && !rdev->constraints->always_on)) {
+
+ /* we are last user */
+ if (regulator_ops_is_valid(rdev, REGULATOR_CHANGE_STATUS)) {
+ ret = _notifier_call_chain(rdev,
+ REGULATOR_EVENT_PRE_DISABLE,
+ NULL);
+ if (ret & NOTIFY_STOP_MASK)
+ return -EINVAL;
+
+ ret = _regulator_do_disable(rdev);
+ if (ret < 0) {
+ rdev_err(rdev, "failed to disable\n");
+ _notifier_call_chain(rdev,
+ REGULATOR_EVENT_ABORT_DISABLE,
+ NULL);
+ return ret;
+ }
+ _notifier_call_chain(rdev, REGULATOR_EVENT_DISABLE,
NULL);
- return ret;
}
- _notifier_call_chain(rdev, REGULATOR_EVENT_DISABLE,
- NULL);
- }
- rdev->use_count = 0;
- } else if (rdev->use_count > 1) {
- rdev->use_count--;
+ rdev->use_count = 0;
+ } else if (rdev->use_count > 1) {
+ rdev->use_count--;
+ }
}
if (ret == 0)
--
2.43.0
From: Chris Riches <chris.riches(a)nutanix.com>
[ Upstream commit 022732e3d846e197539712e51ecada90ded0572a ]
When auditd_set sets the auditd_conn pointer, audit messages can
immediately be put on the socket by other kernel threads. If the backlog
is large or the rate is high, this can immediately fill the socket
buffer. If the audit daemon requested an ACK for this operation, a full
socket buffer causes the ACK to get dropped, also setting ENOBUFS on the
socket.
To avoid this race and ensure ACKs get through, fast-track the ACK in
this specific case to ensure it is sent before auditd_conn is set.
Signed-off-by: Chris Riches <chris.riches(a)nutanix.com>
[PM: fix some tab vs space damage]
Signed-off-by: Paul Moore <paul(a)paul-moore.com>
Signed-off-by: Sasha Levin <sashal(a)kernel.org>
---
kernel/audit.c | 31 ++++++++++++++++++++++++-------
1 file changed, 24 insertions(+), 7 deletions(-)
diff --git a/kernel/audit.c b/kernel/audit.c
index 471d3ad910aa..5fb87eccb8c2 100644
--- a/kernel/audit.c
+++ b/kernel/audit.c
@@ -498,15 +498,19 @@ static void auditd_conn_free(struct rcu_head *rcu)
* @pid: auditd PID
* @portid: auditd netlink portid
* @net: auditd network namespace pointer
+ * @skb: the netlink command from the audit daemon
+ * @ack: netlink ack flag, cleared if ack'd here
*
* Description:
* This function will obtain and drop network namespace references as
* necessary. Returns zero on success, negative values on failure.
*/
-static int auditd_set(struct pid *pid, u32 portid, struct net *net)
+static int auditd_set(struct pid *pid, u32 portid, struct net *net,
+ struct sk_buff *skb, bool *ack)
{
unsigned long flags;
struct auditd_connection *ac_old, *ac_new;
+ struct nlmsghdr *nlh;
if (!pid || !net)
return -EINVAL;
@@ -518,6 +522,13 @@ static int auditd_set(struct pid *pid, u32 portid, struct net *net)
ac_new->portid = portid;
ac_new->net = get_net(net);
+ /* send the ack now to avoid a race with the queue backlog */
+ if (*ack) {
+ nlh = nlmsg_hdr(skb);
+ netlink_ack(skb, nlh, 0, NULL);
+ *ack = false;
+ }
+
spin_lock_irqsave(&auditd_conn_lock, flags);
ac_old = rcu_dereference_protected(auditd_conn,
lockdep_is_held(&auditd_conn_lock));
@@ -1204,7 +1215,8 @@ static int audit_replace(struct pid *pid)
return auditd_send_unicast_skb(skb);
}
-static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
+static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh,
+ bool *ack)
{
u32 seq;
void *data;
@@ -1296,7 +1308,8 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
/* register a new auditd connection */
err = auditd_set(req_pid,
NETLINK_CB(skb).portid,
- sock_net(NETLINK_CB(skb).sk));
+ sock_net(NETLINK_CB(skb).sk),
+ skb, ack);
if (audit_enabled != AUDIT_OFF)
audit_log_config_change("audit_pid",
new_pid,
@@ -1529,9 +1542,10 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
* Parse the provided skb and deal with any messages that may be present,
* malformed skbs are discarded.
*/
-static void audit_receive(struct sk_buff *skb)
+static void audit_receive(struct sk_buff *skb)
{
struct nlmsghdr *nlh;
+ bool ack;
/*
* len MUST be signed for nlmsg_next to be able to dec it below 0
* if the nlmsg_len was not aligned
@@ -1544,9 +1558,12 @@ static void audit_receive(struct sk_buff *skb)
audit_ctl_lock();
while (nlmsg_ok(nlh, len)) {
- err = audit_receive_msg(skb, nlh);
- /* if err or if this message says it wants a response */
- if (err || (nlh->nlmsg_flags & NLM_F_ACK))
+ ack = nlh->nlmsg_flags & NLM_F_ACK;
+ err = audit_receive_msg(skb, nlh, &ack);
+
+ /* send an ack if the user asked for one and audit_receive_msg
+ * didn't already do it, or if there was an error. */
+ if (ack || err)
netlink_ack(skb, nlh, err, NULL);
nlh = nlmsg_next(nlh, &len);
--
2.43.0