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Merge tag 'bpf-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf
Pull bpf fixes from Alexei Starovoitov:
- Fix interaction between livepatch and BPF fexit programs (Song Liu)
With Steven and Masami acks.
- Fix stack ORC unwind from BPF kprobe_multi (Jiri Olsa)
With Steven and Masami acks.
- Fix out of bounds access in widen_imprecise_scalars() in the verifier
(Eduard Zingerman)
- Fix conflicts between MPTCP and BPF sockmap (Jiayuan Chen)
- Fix net_sched storage collision with BPF data_meta/data_end (Eric
Dumazet)
- Add _impl suffix to BPF kfuncs with implicit args to avoid breaking
them in bpf-next when KF_IMPLICIT_ARGS is added (Mykyta Yatsenko)
* tag 'bpf-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf:
selftests/bpf: Test widen_imprecise_scalars() with different stack depth
bpf: account for current allocated stack depth in widen_imprecise_scalars()
bpf: Add bpf_prog_run_data_pointers()
selftests/bpf: Add mptcp test with sockmap
mptcp: Fix proto fallback detection with BPF
mptcp: Disallow MPTCP subflows from sockmap
selftests/bpf: Add stacktrace ips test for raw_tp
selftests/bpf: Add stacktrace ips test for kprobe_multi/kretprobe_multi
x86/fgraph,bpf: Fix stack ORC unwind from kprobe_multi return probe
Revert "perf/x86: Always store regs->ip in perf_callchain_kernel()"
bpf: add _impl suffix for bpf_stream_vprintk() kfunc
bpf:add _impl suffix for bpf_task_work_schedule* kfuncs
selftests/bpf: Add tests for livepatch + bpf trampoline
ftrace: bpf: Fix IPMODIFY + DIRECT in modify_ftrace_direct()
ftrace: Fix BPF fexit with livepatch
syzbot found that cls_bpf_classify() is able to change
tc_skb_cb(skb)->drop_reason triggering a warning in sk_skb_reason_drop().
WARNING: CPU: 0 PID: 5965 at net/core/skbuff.c:1192 __sk_skb_reason_drop net/core/skbuff.c:1189 [inline]
WARNING: CPU: 0 PID: 5965 at net/core/skbuff.c:1192 sk_skb_reason_drop+0x76/0x170 net/core/skbuff.c:1214
struct tc_skb_cb has been added in commit ec624fe740b4 ("net/sched:
Extend qdisc control block with tc control block"), which added a wrong
interaction with db58ba459202 ("bpf: wire in data and data_end for
cls_act_bpf").
drop_reason was added later.
Add bpf_prog_run_data_pointers() helper to save/restore the net_sched
storage colliding with BPF data_meta/data_end.
Fixes: ec624fe740b4 ("net/sched: Extend qdisc control block with tc control block")
Reported-by: syzbot <syzkaller@googlegroups.com>
Closes: https://lore.kernel.org/netdev/6913437c.a70a0220.22f260.013b.GAE@google.com/
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Reviewed-by: Victor Nogueira <victor@mojatatu.com>
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Link: https://patch.msgid.link/20251112125516.1563021-1-edumazet@google.com
After commit 100dfa74cad9 ("inet: dev_queue_xmit() llist adoption")
I started seeing many qdisc requeues on IDPF under high TX workload.
$ tc -s qd sh dev eth1 handle 1: ; sleep 1; tc -s qd sh dev eth1 handle 1:
qdisc mq 1: root
Sent 43534617319319 bytes 268186451819 pkt (dropped 0, overlimits 0 requeues 3532840114)
backlog 1056Kb 6675p requeues 3532840114
qdisc mq 1: root
Sent 43554665866695 bytes 268309964788 pkt (dropped 0, overlimits 0 requeues 3537737653)
backlog 781164b 4822p requeues 3537737653
This is caused by try_bulk_dequeue_skb() being only limited by BQL budget.
perf record -C120-239 -e qdisc:qdisc_dequeue sleep 1 ; perf script
...
netperf 75332 [146] 2711.138269: qdisc:qdisc_dequeue: dequeue ifindex=5 qdisc handle=0x80150000 parent=0x10013 txq_state=0x0 packets=1292 skbaddr=0xff378005a1e9f200
netperf 75332 [146] 2711.138953: qdisc:qdisc_dequeue: dequeue ifindex=5 qdisc handle=0x80150000 parent=0x10013 txq_state=0x0 packets=1213 skbaddr=0xff378004d607a500
netperf 75330 [144] 2711.139631: qdisc:qdisc_dequeue: dequeue ifindex=5 qdisc handle=0x80150000 parent=0x10013 txq_state=0x0 packets=1233 skbaddr=0xff3780046be20100
netperf 75333 [147] 2711.140356: qdisc:qdisc_dequeue: dequeue ifindex=5 qdisc handle=0x80150000 parent=0x10013 txq_state=0x0 packets=1093 skbaddr=0xff37800514845b00
netperf 75337 [151] 2711.141037: qdisc:qdisc_dequeue: dequeue ifindex=5 qdisc handle=0x80150000 parent=0x10013 txq_state=0x0 packets=1353 skbaddr=0xff37800460753300
netperf 75337 [151] 2711.141877: qdisc:qdisc_dequeue: dequeue ifindex=5 qdisc handle=0x80150000 parent=0x10013 txq_state=0x0 packets=1367 skbaddr=0xff378004e72c7b00
netperf 75330 [144] 2711.142643: qdisc:qdisc_dequeue: dequeue ifindex=5 qdisc handle=0x80150000 parent=0x10013 txq_state=0x0 packets=1202 skbaddr=0xff3780045bd60000
...
This is bad because :
1) Large batches hold one victim cpu for a very long time.
2) Driver often hit their own TX ring limit (all slots are used).
3) We call dev_requeue_skb()
4) Requeues are using a FIFO (q->gso_skb), breaking qdisc ability to
implement FQ or priority scheduling.
5) dequeue_skb() gets packets from q->gso_skb one skb at a time
with no xmit_more support. This is causing many spinlock games
between the qdisc and the device driver.
Requeues were supposed to be very rare, lets keep them this way.
Limit batch sizes to /proc/sys/net/core/dev_weight (default 64) as
__qdisc_run() was designed to use.
Fixes: 5772e9a3463b ("qdisc: bulk dequeue support for qdiscs with TCQ_F_ONETXQUEUE")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Toke Høiland-Jørgensen <toke@redhat.com>
Acked-by: Jesper Dangaard Brouer <hawk@kernel.org>
Link: https://patch.msgid.link/20251109161215.2574081-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Fix a KMSAN kernel-infoleak detected by the syzbot .
[net?] KMSAN: kernel-infoleak in __skb_datagram_iter
In tcf_ife_dump(), the variable 'opt' was partially initialized using a
designatied initializer. While the padding bytes are reamined
uninitialized. nla_put() copies the entire structure into a
netlink message, these uninitialized bytes leaked to userspace.
Initialize the structure with memset before assigning its fields
to ensure all members and padding are cleared prior to beign copied.
This change silences the KMSAN report and prevents potential information
leaks from the kernel memory.
This fix has been tested and validated by syzbot. This patch closes the
bug reported at the following syzkaller link and ensures no infoleak.
Reported-by: syzbot+0c85cae3350b7d486aee@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=0c85cae3350b7d486aee
Tested-by: syzbot+0c85cae3350b7d486aee@syzkaller.appspotmail.com
Fixes: ef6980b6becb ("introduce IFE action")
Signed-off-by: Ranganath V N <vnranganath.20@gmail.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20251109091336.9277-3-vnranganath.20@gmail.com
Acked-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Wang reported an illegal configuration [1] where the user attempts to add a
child qdisc to the ingress qdisc as follows:
tc qdisc add dev eth0 handle ffff:0 ingress
tc qdisc add dev eth0 handle ffe0:0 parent ffff:a fq
To solve this, we reject any configuration attempt to add a child qdisc to
ingress or clsact.
[1] https://lore.kernel.org/netdev/20251105022213.1981982-1-wangliang74@huawei.com/
Fixes: 5e50da01d0ce ("[NET_SCHED]: Fix endless loops (part 2): "simple" qdiscs")
Reported-by: Wang Liang <wangliang74@huawei.com>
Closes: https://lore.kernel.org/netdev/20251105022213.1981982-1-wangliang74@huawei.com/
Reviewed-by: Pedro Tammela <pctammela@mojatatu.ai>
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: Victor Nogueira <victor@mojatatu.com>
Reviewed-by: Cong Wang <cwang@multikernel.io>
Link: https://patch.msgid.link/20251106205621.3307639-1-victor@mojatatu.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
tcfa_qstats is currently only used to hold drops and overlimits counters.
tcf_action_inc_drop_qstats() and tcf_action_inc_overlimit_qstats()
currently acquire a->tcfa_lock to increment these counters.
Switch to two atomic_t to get lock-free accounting.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Jamal Hadi Salim <jhs@mojatatu.com>
Link: https://patch.msgid.link/20250901093141.2093176-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Jamal reported that we had to use BH safety after all,
because stats can be updated from BH handler.
Fixes: 3133d5c15cb5 ("net_sched: remove BH blocking in eight actions")
Fixes: 53df77e78590 ("net_sched: act_skbmod: use RCU in tcf_skbmod_dump()")
Fixes: e97ae742972f ("net_sched: act_tunnel_key: use RCU in tunnel_key_dump()")
Fixes: 48b5e5dbdb23 ("net_sched: act_vlan: use RCU in tcf_vlan_dump()")
Reported-by: Jamal Hadi Salim <jhs@mojatatu.com>
Closes: https://lore.kernel.org/netdev/CAM0EoMmhq66EtVqDEuNik8MVFZqkgxFbMu=fJtbNoYD7YXg4bA@mail.gmail.com/
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Jamal Hadi Salim <jhs@mojatatu.com>
Link: https://patch.msgid.link/20250901092608.2032473-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Also storing tcf_action into struct tcf_skbmod_params
makes sure there is no discrepancy in tcf_skbmod_act().
No longer block BH in tcf_skbmod_init() when acquiring tcf_lock.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20250827125349.3505302-5-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Also storing tcf_action into struct tcf_tunnel_key_params
makes sure there is no discrepancy in tunnel_key_act().
No longer block BH in tunnel_key_init() when acquiring tcf_lock.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20250827125349.3505302-4-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Also storing tcf_action into struct tcf_vlan_params
makes sure there is no discrepancy in tcf_vlan_act().
No longer block BH in tcf_vlan_init() when acquiring tcf_lock.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20250827125349.3505302-3-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Followup of f45b45cbfae3 ("Merge branch
'net_sched-act-extend-rcu-use-in-dump-methods'")
We never grab tcf_lock from BH context in these modules:
act_connmark
act_csum
act_ct
act_ctinfo
act_mpls
act_nat
act_pedit
act_skbedit
No longer block BH when acquiring tcf_lock from init functions.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20250827125349.3505302-2-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
The WARN_ON trigger based on !cl->leaf.q->q.qlen is unnecessary in
htb_activate. htb_dequeue_tree already accounts for that scenario.
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: William Liu <will@willsroot.io>
Reviewed-by: Savino Dicanosa <savy@syst3mfailure.io>
Link: https://patch.msgid.link/20250819033632.579854-1-will@willsroot.io
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
The following setup can trigger a WARNING in htb_activate due to
the condition: !cl->leaf.q->q.qlen
tc qdisc del dev lo root
tc qdisc add dev lo root handle 1: htb default 1
tc class add dev lo parent 1: classid 1:1 \
htb rate 64bit
tc qdisc add dev lo parent 1:1 handle f: \
cake memlimit 1b
ping -I lo -f -c1 -s64 -W0.001 127.0.0.1
This is because the low memlimit leads to a low buffer_limit, which
causes packet dropping. However, cake_enqueue still returns
NET_XMIT_SUCCESS, causing htb_enqueue to call htb_activate with an
empty child qdisc. We should return NET_XMIT_CN when packets are
dropped from the same tin and flow.
I do not believe return value of NET_XMIT_CN is necessary for packet
drops in the case of ack filtering, as that is meant to optimize
performance, not to signal congestion.
Fixes: 046f6fd5daef ("sched: Add Common Applications Kept Enhanced (cake) qdisc")
Signed-off-by: William Liu <will@willsroot.io>
Reviewed-by: Savino Dicanosa <savy@syst3mfailure.io>
Acked-by: Toke Høiland-Jørgensen <toke@toke.dk>
Reviewed-by: Jamal Hadi Salim <jhs@mojatatu.com>
Link: https://patch.msgid.link/20250819033601.579821-1-will@willsroot.io
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
When a user creates a dualpi2 qdisc it automatically sets a timer. This
timer will run constantly and update the qdisc's probability field.
The issue is that the timer acquires the qdisc root lock and runs in
hardirq. The qdisc root lock is also acquired in dev.c whenever a packet
arrives for this qdisc. Since the dualpi2 timer callback runs in hardirq,
it may interrupt the packet processing running in softirq. If that happens
and it runs on the same CPU, it will acquire the same lock and cause a
deadlock. The following splat shows up when running a kernel compiled with
lock debugging:
[ +0.000224] WARNING: inconsistent lock state
[ +0.000224] 6.16.0+ #10 Not tainted
[ +0.000169] --------------------------------
[ +0.000029] inconsistent {IN-HARDIRQ-W} -> {HARDIRQ-ON-W} usage.
[ +0.000000] ping/156 [HC0[0]:SC0[2]:HE1:SE0] takes:
[ +0.000000] ffff897841242110 (&sch->root_lock_key){?.-.}-{3:3}, at: __dev_queue_xmit+0x86d/0x1140
[ +0.000000] {IN-HARDIRQ-W} state was registered at:
[ +0.000000] lock_acquire.part.0+0xb6/0x220
[ +0.000000] _raw_spin_lock+0x31/0x80
[ +0.000000] dualpi2_timer+0x6f/0x270
[ +0.000000] __hrtimer_run_queues+0x1c5/0x360
[ +0.000000] hrtimer_interrupt+0x115/0x260
[ +0.000000] __sysvec_apic_timer_interrupt+0x6d/0x1a0
[ +0.000000] sysvec_apic_timer_interrupt+0x6e/0x80
[ +0.000000] asm_sysvec_apic_timer_interrupt+0x1a/0x20
[ +0.000000] pv_native_safe_halt+0xf/0x20
[ +0.000000] default_idle+0x9/0x10
[ +0.000000] default_idle_call+0x7e/0x1e0
[ +0.000000] do_idle+0x1e8/0x250
[ +0.000000] cpu_startup_entry+0x29/0x30
[ +0.000000] rest_init+0x151/0x160
[ +0.000000] start_kernel+0x6f3/0x700
[ +0.000000] x86_64_start_reservations+0x24/0x30
[ +0.000000] x86_64_start_kernel+0xc8/0xd0
[ +0.000000] common_startup_64+0x13e/0x148
[ +0.000000] irq event stamp: 6884
[ +0.000000] hardirqs last enabled at (6883): [<ffffffffa75700b3>] neigh_resolve_output+0x223/0x270
[ +0.000000] hardirqs last disabled at (6882): [<ffffffffa7570078>] neigh_resolve_output+0x1e8/0x270
[ +0.000000] softirqs last enabled at (6880): [<ffffffffa757006b>] neigh_resolve_output+0x1db/0x270
[ +0.000000] softirqs last disabled at (6884): [<ffffffffa755b533>] __dev_queue_xmit+0x73/0x1140
[ +0.000000]
other info that might help us debug this:
[ +0.000000] Possible unsafe locking scenario:
[ +0.000000] CPU0
[ +0.000000] ----
[ +0.000000] lock(&sch->root_lock_key);
[ +0.000000] <Interrupt>
[ +0.000000] lock(&sch->root_lock_key);
[ +0.000000]
*** DEADLOCK ***
[ +0.000000] 4 locks held by ping/156:
[ +0.000000] #0: ffff897842332e08 (sk_lock-AF_INET){+.+.}-{0:0}, at: raw_sendmsg+0x41e/0xf40
[ +0.000000] #1: ffffffffa816f880 (rcu_read_lock){....}-{1:3}, at: ip_output+0x2c/0x190
[ +0.000000] #2: ffffffffa816f880 (rcu_read_lock){....}-{1:3}, at: ip_finish_output2+0xad/0x950
[ +0.000000] #3: ffffffffa816f840 (rcu_read_lock_bh){....}-{1:3}, at: __dev_queue_xmit+0x73/0x1140
I am able to reproduce it consistently when running the following:
tc qdisc add dev lo handle 1: root dualpi2
ping -f 127.0.0.1
To fix it, make the timer run in softirq.
Fixes: 320d031ad6e4 ("sched: Struct definition and parsing of dualpi2 qdisc")
Reviewed-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: Victor Nogueira <victor@mojatatu.com>
Link: https://patch.msgid.link/20250815135317.664993-1-victor@mojatatu.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
This issue applies for the following qdiscs: hhf, fq, fq_codel, and
fq_pie, and occurs in their change handlers when adjusting to the new
limit. The problem is the following in the values passed to the
subsequent qdisc_tree_reduce_backlog call given a tbf parent:
When the tbf parent runs out of tokens, skbs of these qdiscs will
be placed in gso_skb. Their peek handlers are qdisc_peek_dequeued,
which accounts for both qlen and backlog. However, in the case of
qdisc_dequeue_internal, ONLY qlen is accounted for when pulling
from gso_skb. This means that these qdiscs are missing a
qdisc_qstats_backlog_dec when dropping packets to satisfy the
new limit in their change handlers.
One can observe this issue with the following (with tc patched to
support a limit of 0):
export TARGET=fq
tc qdisc del dev lo root
tc qdisc add dev lo root handle 1: tbf rate 8bit burst 100b latency 1ms
tc qdisc replace dev lo handle 3: parent 1:1 $TARGET limit 1000
echo ''; echo 'add child'; tc -s -d qdisc show dev lo
ping -I lo -f -c2 -s32 -W0.001 127.0.0.1 2>&1 >/dev/null
echo ''; echo 'after ping'; tc -s -d qdisc show dev lo
tc qdisc change dev lo handle 3: parent 1:1 $TARGET limit 0
echo ''; echo 'after limit drop'; tc -s -d qdisc show dev lo
tc qdisc replace dev lo handle 2: parent 1:1 sfq
echo ''; echo 'post graft'; tc -s -d qdisc show dev lo
The second to last show command shows 0 packets but a positive
number (74) of backlog bytes. The problem becomes clearer in the
last show command, where qdisc_purge_queue triggers
qdisc_tree_reduce_backlog with the positive backlog and causes an
underflow in the tbf parent's backlog (4096 Mb instead of 0).
To fix this issue, the codepath for all clients of qdisc_dequeue_internal
has been simplified: codel, pie, hhf, fq, fq_pie, and fq_codel.
qdisc_dequeue_internal handles the backlog adjustments for all cases that
do not directly use the dequeue handler.
The old fq_codel_change limit adjustment loop accumulated the arguments to
the subsequent qdisc_tree_reduce_backlog call through the cstats field.
However, this is confusing and error prone as fq_codel_dequeue could also
potentially mutate this field (which qdisc_dequeue_internal calls in the
non gso_skb case), so we have unified the code here with other qdiscs.
Fixes: 2d3cbfd6d54a ("net_sched: Flush gso_skb list too during ->change()")
Fixes: 4b549a2ef4be ("fq_codel: Fair Queue Codel AQM")
Fixes: 10239edf86f1 ("net-qdisc-hhf: Heavy-Hitter Filter (HHF) qdisc")
Signed-off-by: William Liu <will@willsroot.io>
Reviewed-by: Savino Dicanosa <savy@syst3mfailure.io>
Link: https://patch.msgid.link/20250812235725.45243-1-will@willsroot.io
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Cross-merge networking fixes after downstream PR (net-6.17-rc2).
No conflicts.
Adjacent changes:
drivers/net/ethernet/stmicro/stmmac/dwmac-rk.c
d7a276a5768f ("net: stmmac: rk: convert to suspend()/resume() methods")
de1e963ad064 ("net: stmmac: rk: put the PHY clock on remove")
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
The call to nla_strscpy() already zero-pads the tail of the destination
buffer which makes the additional memset(0) call redundant. Remove it.
Signed-off-by: Thorsten Blum <thorsten.blum@linux.dev>
Reviewed-by: Joe Damato <joe@dama.to>
Link: https://patch.msgid.link/20250811164039.43250-1-thorsten.blum@linux.dev
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
TCA_MQPRIO_TC_ENTRY_INDEX is validated using
NLA_POLICY_MAX(NLA_U32, TC_QOPT_MAX_QUEUE), which allows the value
TC_QOPT_MAX_QUEUE (16). This leads to a 4-byte out-of-bounds stack
write in the fp[] array, which only has room for 16 elements (0–15).
Fix this by changing the policy to allow only up to TC_QOPT_MAX_QUEUE - 1.
Fixes: f62af20bed2d ("net/sched: mqprio: allow per-TC user input of FP adminStatus")
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Maher Azzouzi <maherazz04@gmail.com>
Reviewed-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Link: https://patch.msgid.link/20250802001857.2702497-1-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Syzbot reported a WARNING in taprio_get_start_time().
When link speed is 470,589 or greater, q->picos_per_byte becomes too
small, causing length_to_duration(q, ETH_ZLEN) to return zero.
This zero value leads to validation failures in fill_sched_entry() and
parse_taprio_schedule(), allowing arbitrary values to be assigned to
entry->interval and cycle_time. As a result, sched->cycle can become zero.
Since SPEED_800000 is the largest defined speed in
include/uapi/linux/ethtool.h, this issue can occur in realistic scenarios.
To ensure length_to_duration() returns a non-zero value for minimum-sized
Ethernet frames (ETH_ZLEN = 60), picos_per_byte must be at least 17
(60 * 17 > PSEC_PER_NSEC which is 1000).
This patch enforces a minimum value of 17 for picos_per_byte when the
calculated value would be lower, and adds a warning message to inform
users that scheduling accuracy may be affected at very high link speeds.
Fixes: fb66df20a720 ("net/sched: taprio: extend minimum interval restriction to entire cycle too")
Reported-by: syzbot+398e1ee4ca2cac05fddb@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=398e1ee4ca2cac05fddb
Signed-off-by: Takamitsu Iwai <takamitz@amazon.co.jp>
Link: https://patch.msgid.link/20250728173149.45585-1-takamitz@amazon.co.jp
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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Merge tag 'bpf-next-6.17' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Pull bpf updates from Alexei Starovoitov:
- Remove usermode driver (UMD) framework (Thomas Weißschuh)
- Introduce Strongly Connected Component (SCC) in the verifier to
detect loops and refine register liveness (Eduard Zingerman)
- Allow 'void *' cast using bpf_rdonly_cast() and corresponding
'__arg_untrusted' for global function parameters (Eduard Zingerman)
- Improve precision for BPF_ADD and BPF_SUB operations in the verifier
(Harishankar Vishwanathan)
- Teach the verifier that constant pointer to a map cannot be NULL
(Ihor Solodrai)
- Introduce BPF streams for error reporting of various conditions
detected by BPF runtime (Kumar Kartikeya Dwivedi)
- Teach the verifier to insert runtime speculation barrier (lfence on
x86) to mitigate speculative execution instead of rejecting the
programs (Luis Gerhorst)
- Various improvements for 'veristat' (Mykyta Yatsenko)
- For CONFIG_DEBUG_KERNEL config warn on internal verifier errors to
improve bug detection by syzbot (Paul Chaignon)
- Support BPF private stack on arm64 (Puranjay Mohan)
- Introduce bpf_cgroup_read_xattr() kfunc to read xattr of cgroup's
node (Song Liu)
- Introduce kfuncs for read-only string opreations (Viktor Malik)
- Implement show_fdinfo() for bpf_links (Tao Chen)
- Reduce verifier's stack consumption (Yonghong Song)
- Implement mprog API for cgroup-bpf programs (Yonghong Song)
* tag 'bpf-next-6.17' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (192 commits)
selftests/bpf: Migrate fexit_noreturns case into tracing_failure test suite
selftests/bpf: Add selftest for attaching tracing programs to functions in deny list
bpf: Add log for attaching tracing programs to functions in deny list
bpf: Show precise rejected function when attaching fexit/fmod_ret to __noreturn functions
bpf: Fix various typos in verifier.c comments
bpf: Add third round of bounds deduction
selftests/bpf: Test invariants on JSLT crossing sign
selftests/bpf: Test cross-sign 64bits range refinement
selftests/bpf: Update reg_bound range refinement logic
bpf: Improve bounds when s64 crosses sign boundary
bpf: Simplify bounds refinement from s32
selftests/bpf: Enable private stack tests for arm64
bpf, arm64: JIT support for private stack
bpf: Move bpf_jit_get_prog_name() to core.c
bpf, arm64: Fix fp initialization for exception boundary
umd: Remove usermode driver framework
bpf/preload: Don't select USERMODE_DRIVER
selftests/bpf: Fix test dynptr/test_dynptr_memset_xdp_chunks failure
selftests/bpf: Fix test dynptr/test_dynptr_copy_xdp failure
selftests/bpf: Increase xdp data size for arm64 64K page size
...
Both taprio and mqprio have code to validate respective entry index
attributes. The validation is indented to ensure that the attribute is
present, and that it's value is in range, and that each value is only
used once.
The purpose of this patch is to align the implementation of taprio with
that of mqprio as there seems to be no good reason for them to differ.
For one thing, this way, bugs will be present in both or neither.
As a follow-up some consideration could be given to a common function
used by both sch.
No functional change intended.
Except of tdc run: the results of the taprio tests
# ok 81 ba39 - Add taprio Qdisc to multi-queue device (8 queues)
# ok 82 9462 - Add taprio Qdisc with multiple sched-entry
# ok 83 8d92 - Add taprio Qdisc with txtime-delay
# ok 84 d092 - Delete taprio Qdisc with valid handle
# ok 85 8471 - Show taprio class
# ok 86 0a85 - Add taprio Qdisc to single-queue device
# ok 87 6f62 - Add taprio Qdisc with too short interval
# ok 88 831f - Add taprio Qdisc with too short cycle-time
# ok 89 3e1e - Add taprio Qdisc with an invalid cycle-time
# ok 90 39b4 - Reject grafting taprio as child qdisc of software taprio
# ok 91 e8a1 - Reject grafting taprio as child qdisc of offloaded taprio
# ok 92 a7bf - Graft cbs as child of software taprio
# ok 93 6a83 - Graft cbs as child of offloaded taprio
Cc: Vladimir Oltean <vladimir.oltean@nxp.com>
Cc: Maher Azzouzi <maherazz04@gmail.com>
Link: https://lore.kernel.org/netdev/20250723125521.GA2459@horms.kernel.org/
Signed-off-by: Simon Horman <horms@kernel.org>
Reviewed-by: Cong Wang <xiyou.wangcong@gmail.com>
Acked-by: Vinicius Costa Gomes <vinicius.gomes@intel.com>
Link: https://patch.msgid.link/20250725-taprio-idx-parse-v1-1-b582fffcde37@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Currently, packets dropped by pfifo_fast due to queue overflow are
marked with a generic SKB_DROP_REASON_QDISC_DROP in __dev_xmit_skb().
This patch adds explicit drop reason SKB_DROP_REASON_QDISC_OVERLIMIT
for queue-full cases, providing better distinction from other qdisc drops.
Signed-off-by: Fan Yu <fan.yu9@zte.com.cn>
Reviewed-by: Cong Wang <xiyou.wangcong@gmail.com>
Link: https://patch.msgid.link/20250724212837119BP9HOs0ibXDRWgsXMMir7@zte.com.cn
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
DualPI2 provides L4S-type low latency & loss to traffic that uses a
scalable congestion controller (e.g. TCP-Prague, DCTCP) without
degrading the performance of 'classic' traffic (e.g. Reno,
Cubic etc.). It is to be the reference implementation of IETF RFC9332
DualQ Coupled AQM (https://datatracker.ietf.org/doc/html/rfc9332).
Note that creating two independent queues cannot meet the goal of
DualPI2 mentioned in RFC9332: "...to preserve fairness between
ECN-capable and non-ECN-capable traffic." Further, it could even
lead to starvation of Classic traffic, which is also inconsistent
with the requirements in RFC9332: "...although priority MUST be
bounded in order not to starve Classic traffic." DualPI2 is
designed to maintain approximate per-flow fairness on L-queue and
C-queue by forming a single qdisc using the coupling factor and
scheduler between two queues.
The qdisc provides two queues called low latency and classic. It
classifies packets based on the ECN field in the IP headers. By
default it directs non-ECN and ECT(0) into the classic queue and
ECT(1) and CE into the low latency queue, as per the IETF spec.
Each queue runs its own AQM:
* The classic AQM is called PI2, which is similar to the PIE AQM but
more responsive and simpler. Classic traffic requires a decent
target queue (default 15ms for Internet deployment) to fully
utilize the link and to avoid high drop rates.
* The low latency AQM is, by default, a very shallow ECN marking
threshold (1ms) similar to that used for DCTCP.
The DualQ isolates the low queuing delay of the Low Latency queue
from the larger delay of the 'Classic' queue. However, from a
bandwidth perspective, flows in either queue will share out the link
capacity as if there was just a single queue. This bandwidth pooling
effect is achieved by coupling together the drop and ECN-marking
probabilities of the two AQMs.
The PI2 AQM has two main parameters in addition to its target delay.
The integral gain factor alpha is used to slowly correct any persistent
standing queue error from the target delay, while the proportional gain
factor beta is used to quickly compensate for queue changes (growth or
shrinkage). Either alpha and beta are given as a parameter, or they can
be calculated by tc from alternative typical and maximum RTT parameters.
Internally, the output of a linear Proportional Integral (PI)
controller is used for both queues. This output is squared to
calculate the drop or ECN-marking probability of the classic queue.
This counterbalances the square-root rate equation of Reno/Cubic,
which is the trick that balances flow rates across the queues. For
the ECN-marking probability of the low latency queue, the output of
the base AQM is multiplied by a coupling factor. This determines the
balance between the flow rates in each queue. The default setting
makes the flow rates roughly equal, which should be generally
applicable.
If DUALPI2 AQM has detected overload (due to excessive non-responsive
traffic in either queue), it will switch to signaling congestion
solely using drop, irrespective of the ECN field. Alternatively, it
can be configured to limit the drop probability and let the queue
grow and eventually overflow (like tail-drop).
GSO splitting in DUALPI2 is configurable from userspace while the
default behavior is to split gso. When running DUALPI2 at unshaped
10gigE with 4 download streams test, splitting gso apart results in
halving the latency with no loss in throughput:
Summary of tcp_4down run 'no_split_gso':
avg median # data pts
Ping (ms) ICMP : 0.53 0.30 ms 350
TCP download avg : 2326.86 N/A Mbits/s 350
TCP download sum : 9307.42 N/A Mbits/s 350
TCP download::1 : 2672.99 2568.73 Mbits/s 350
TCP download::2 : 2586.96 2570.51 Mbits/s 350
TCP download::3 : 1786.26 1798.82 Mbits/s 350
TCP download::4 : 2261.21 2309.49 Mbits/s 350
Summart of tcp_4down run 'split_gso':
avg median # data pts
Ping (ms) ICMP : 0.22 0.23 ms 350
TCP download avg : 2335.02 N/A Mbits/s 350
TCP download sum : 9340.09 N/A Mbits/s 350
TCP download::1 : 2335.30 2334.22 Mbits/s 350
TCP download::2 : 2334.72 2334.20 Mbits/s 350
TCP download::3 : 2335.28 2334.58 Mbits/s 350
TCP download::4 : 2334.79 2334.39 Mbits/s 350
A similar result is observed when running DUALPI2 at unshaped 1gigE
with 1 download stream test:
Summary of tcp_1down run 'no_split_gso':
avg median # data pts
Ping (ms) ICMP : 1.13 1.25 ms 350
TCP download : 941.41 941.46 Mbits/s 350
Summart of tcp_1down run 'split_gso':
avg median # data pts
Ping (ms) ICMP : 0.51 0.55 ms 350
TCP download : 941.41 941.45 Mbits/s 350
Additional details can be found in the draft:
https://datatracker.ietf.org/doc/html/rfc9332
Signed-off-by: Koen De Schepper <koen.de_schepper@nokia-bell-labs.com>
Co-developed-by: Olga Albisser <olga@albisser.org>
Signed-off-by: Olga Albisser <olga@albisser.org>
Co-developed-by: Olivier Tilmans <olivier.tilmans@nokia.com>
Signed-off-by: Olivier Tilmans <olivier.tilmans@nokia.com>
Co-developed-by: Henrik Steen <henrist@henrist.net>
Signed-off-by: Henrik Steen <henrist@henrist.net>
Co-developed-by: Chia-Yu Chang <chia-yu.chang@nokia-bell-labs.com>
Signed-off-by: Chia-Yu Chang <chia-yu.chang@nokia-bell-labs.com>
Signed-off-by: Bob Briscoe <research@bobbriscoe.net>
Signed-off-by: Ilpo Järvinen <ij@kernel.org>
Acked-by: Dave Taht <dave.taht@gmail.com>
Link: https://patch.msgid.link/20250722095915.24485-4-chia-yu.chang@nokia-bell-labs.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
The configuration and statistics dump of the DualPI2 Qdisc provides
information related to both queues, such as packet numbers and queuing
delays in the L-queue and C-queue, as well as general information such as
probability value, WRR credits, memory usage, packet marking counters, max
queue size, etc.
The following patch includes enqueue/dequeue for DualPI2.
Signed-off-by: Chia-Yu Chang <chia-yu.chang@nokia-bell-labs.com>
Link: https://patch.msgid.link/20250722095915.24485-3-chia-yu.chang@nokia-bell-labs.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
DualPI2 is the reference implementation of IETF RFC9332 DualQ Coupled
AQM (https://datatracker.ietf.org/doc/html/rfc9332) providing two
queues called low latency (L-queue) and classic (C-queue). By default,
it enqueues non-ECN and ECT(0) packets into the C-queue and ECT(1) and
CE packets into the low latency queue (L-queue), as per IETF RFC9332 spec.
This patch defines the dualpi2 Qdisc structure and parsing, and the
following two patches include dumping and enqueue/dequeue for the DualPI2.
Signed-off-by: Chia-Yu Chang <chia-yu.chang@nokia-bell-labs.com>
Link: https://patch.msgid.link/20250722095915.24485-2-chia-yu.chang@nokia-bell-labs.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
might_sleep could be trigger in the atomic context in qfq_delete_class.
qfq_destroy_class was moved into atomic context locked
by sch_tree_lock to avoid a race condition bug on
qfq_aggregate. However, might_sleep could be triggered by
qfq_destroy_class, which introduced sleeping in atomic context (path:
qfq_destroy_class->qdisc_put->__qdisc_destroy->lockdep_unregister_key
->might_sleep).
Considering the race is on the qfq_aggregate objects, keeping
qfq_rm_from_agg in the lock but moving the left part out can solve
this issue.
Fixes: 5e28d5a3f774 ("net/sched: sch_qfq: Fix race condition on qfq_aggregate")
Reported-by: Dan Carpenter <dan.carpenter@linaro.org>
Signed-off-by: Xiang Mei <xmei5@asu.edu>
Link: https://patch.msgid.link/4a04e0cc-a64b-44e7-9213-2880ed641d77@sabinyo.mountain
Reviewed-by: Cong Wang <xiyou.wangcong@gmail.com>
Reviewed-by: Dan Carpenter <dan.carpenter@linaro.org>
Link: https://patch.msgid.link/20250717230128.159766-1-xmei5@asu.edu
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
htb_lookup_leaf has a BUG_ON that can trigger with the following:
tc qdisc del dev lo root
tc qdisc add dev lo root handle 1: htb default 1
tc class add dev lo parent 1: classid 1:1 htb rate 64bit
tc qdisc add dev lo parent 1:1 handle 2: netem
tc qdisc add dev lo parent 2:1 handle 3: blackhole
ping -I lo -c1 -W0.001 127.0.0.1
The root cause is the following:
1. htb_dequeue calls htb_dequeue_tree which calls the dequeue handler on
the selected leaf qdisc
2. netem_dequeue calls enqueue on the child qdisc
3. blackhole_enqueue drops the packet and returns a value that is not
just NET_XMIT_SUCCESS
4. Because of this, netem_dequeue calls qdisc_tree_reduce_backlog, and
since qlen is now 0, it calls htb_qlen_notify -> htb_deactivate ->
htb_deactiviate_prios -> htb_remove_class_from_row -> htb_safe_rb_erase
5. As this is the only class in the selected hprio rbtree,
__rb_change_child in __rb_erase_augmented sets the rb_root pointer to
NULL
6. Because blackhole_dequeue returns NULL, netem_dequeue returns NULL,
which causes htb_dequeue_tree to call htb_lookup_leaf with the same
hprio rbtree, and fail the BUG_ON
The function graph for this scenario is shown here:
0) | htb_enqueue() {
0) + 13.635 us | netem_enqueue();
0) 4.719 us | htb_activate_prios();
0) # 2249.199 us | }
0) | htb_dequeue() {
0) 2.355 us | htb_lookup_leaf();
0) | netem_dequeue() {
0) + 11.061 us | blackhole_enqueue();
0) | qdisc_tree_reduce_backlog() {
0) | qdisc_lookup_rcu() {
0) 1.873 us | qdisc_match_from_root();
0) 6.292 us | }
0) 1.894 us | htb_search();
0) | htb_qlen_notify() {
0) 2.655 us | htb_deactivate_prios();
0) 6.933 us | }
0) + 25.227 us | }
0) 1.983 us | blackhole_dequeue();
0) + 86.553 us | }
0) # 2932.761 us | qdisc_warn_nonwc();
0) | htb_lookup_leaf() {
0) | BUG_ON();
------------------------------------------
The full original bug report can be seen here [1].
We can fix this just by returning NULL instead of the BUG_ON,
as htb_dequeue_tree returns NULL when htb_lookup_leaf returns
NULL.
[1] https://lore.kernel.org/netdev/pF5XOOIim0IuEfhI-SOxTgRvNoDwuux7UHKnE_Y5-zVd4wmGvNk2ceHjKb8ORnzw0cGwfmVu42g9dL7XyJLf1NEzaztboTWcm0Ogxuojoeo=@willsroot.io/
Fixes: 512bb43eb542 ("pkt_sched: sch_htb: Optimize WARN_ONs in htb_dequeue_tree() etc.")
Signed-off-by: William Liu <will@willsroot.io>
Signed-off-by: Savino Dicanosa <savy@syst3mfailure.io>
Link: https://patch.msgid.link/20250717022816.221364-1-will@willsroot.io
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
A race condition can occur when 'agg' is modified in qfq_change_agg
(called during qfq_enqueue) while other threads access it
concurrently. For example, qfq_dump_class may trigger a NULL
dereference, and qfq_delete_class may cause a use-after-free.
This patch addresses the issue by:
1. Moved qfq_destroy_class into the critical section.
2. Added sch_tree_lock protection to qfq_dump_class and
qfq_dump_class_stats.
Fixes: 462dbc9101ac ("pkt_sched: QFQ Plus: fair-queueing service at DRR cost")
Signed-off-by: Xiang Mei <xmei5@asu.edu>
Reviewed-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Also storing tcf_action into struct tcf_skbedit_params
makes sure there is no discrepancy in tcf_skbedit_act().
Signed-off-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20250709090204.797558-12-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Also storing tcf_action into struct tcf_police_params
makes sure there is no discrepancy in tcf_police_act().
Signed-off-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20250709090204.797558-11-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Also storing tcf_action into struct tcf_pedit_params
makes sure there is no discrepancy in tcf_pedit_act().
Signed-off-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20250709090204.797558-10-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Also storing tcf_action into struct tcf_nat_params
makes sure there is no discrepancy in tcf_nat_act().
Signed-off-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20250709090204.797558-9-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Also storing tcf_action into struct tcf_mpls_params
makes sure there is no discrepancy in tcf_mpls_act().
Signed-off-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20250709090204.797558-8-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Also storing tcf_action into struct tcf_ctinfo_params
makes sure there is no discrepancy in tcf_ctinfo_act().
Signed-off-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20250709090204.797558-7-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Commit 21c167aa0ba9 ("net/sched: act_ctinfo: use percpu stats")
missed that stats_dscp_set, stats_dscp_error and stats_cpmark_set
might be written (and read) locklessly.
Use atomic64_t for these three fields, I doubt act_ctinfo is used
heavily on big SMP hosts anyway.
Fixes: 24ec483cec98 ("net: sched: Introduce act_ctinfo action")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Pedro Tammela <pctammela@mojatatu.com>
Link: https://patch.msgid.link/20250709090204.797558-6-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Also storing tcf_action into struct tcf_ct_params
makes sure there is no discrepancy in tcf_ct_act().
Signed-off-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20250709090204.797558-5-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Also storing tcf_action into struct tcf_csum_params
makes sure there is no discrepancy in tcf_csum_act().
Signed-off-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20250709090204.797558-4-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Also storing tcf_action into struct tcf_connmark_parms
makes sure there is no discrepancy in tcf_connmark_act().
Signed-off-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20250709090204.797558-3-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
netem_enqueue's duplication prevention logic breaks when a netem
resides in a qdisc tree with other netems - this can lead to a
soft lockup and OOM loop in netem_dequeue, as seen in [1].
Ensure that a duplicating netem cannot exist in a tree with other
netems.
Previous approaches suggested in discussions in chronological order:
1) Track duplication status or ttl in the sk_buff struct. Considered
too specific a use case to extend such a struct, though this would
be a resilient fix and address other previous and potential future
DOS bugs like the one described in loopy fun [2].
2) Restrict netem_enqueue recursion depth like in act_mirred with a
per cpu variable. However, netem_dequeue can call enqueue on its
child, and the depth restriction could be bypassed if the child is a
netem.
3) Use the same approach as in 2, but add metadata in netem_skb_cb
to handle the netem_dequeue case and track a packet's involvement
in duplication. This is an overly complex approach, and Jamal
notes that the skb cb can be overwritten to circumvent this
safeguard.
4) Prevent the addition of a netem to a qdisc tree if its ancestral
path contains a netem. However, filters and actions can cause a
packet to change paths when re-enqueued to the root from netem
duplication, leading us to the current solution: prevent a
duplicating netem from inhabiting the same tree as other netems.
[1] https://lore.kernel.org/netdev/8DuRWwfqjoRDLDmBMlIfbrsZg9Gx50DHJc1ilxsEBNe2D6NMoigR_eIRIG0LOjMc3r10nUUZtArXx4oZBIdUfZQrwjcQhdinnMis_0G7VEk=@willsroot.io/
[2] https://lwn.net/Articles/719297/
Fixes: 0afb51e72855 ("[PKT_SCHED]: netem: reinsert for duplication")
Reported-by: William Liu <will@willsroot.io>
Reported-by: Savino Dicanosa <savy@syst3mfailure.io>
Signed-off-by: William Liu <will@willsroot.io>
Signed-off-by: Savino Dicanosa <savy@syst3mfailure.io>
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Link: https://patch.msgid.link/20250708164141.875402-1-will@willsroot.io
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
To prevent a potential crash in agg_dequeue (net/sched/sch_qfq.c)
when cl->qdisc->ops->peek(cl->qdisc) returns NULL, we check the return
value before using it, similar to the existing approach in sch_hfsc.c.
To avoid code duplication, the following changes are made:
1. Changed qdisc_warn_nonwc(include/net/pkt_sched.h) into a static
inline function.
2. Moved qdisc_peek_len from net/sched/sch_hfsc.c to
include/net/pkt_sched.h so that sch_qfq can reuse it.
3. Applied qdisc_peek_len in agg_dequeue to avoid crashing.
Signed-off-by: Xiang Mei <xmei5@asu.edu>
Reviewed-by: Cong Wang <xiyou.wangcong@gmail.com>
Link: https://patch.msgid.link/20250705212143.3982664-1-xmei5@asu.edu
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
