kernel/linux.git/net/sched, branch v6.1.175

net/sched: sch_pie: annotate more data-races in pie_dump_stats()

2026-06-01T15:39:31+00:00

[ Upstream commit 6d4106e8df94c0c52cf3ca6a6a0d01567fb3844e ] My prior patch missed few READ_ONCE()/WRITE_ONCE() annotations. Fixes: 5154561d9b11 ("net/sched: sch_pie: annotate data-races in pie_dump_stats()") Signed-off-by: Eric Dumazet Link: https://patch.msgid.link/20260430080056.35104-1-edumazet@google.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin

net/sched: cls_flower: revert unintended changes

2026-06-01T15:39:30+00:00

[ Upstream commit 1e01abec856593e02cd69fd95b784c10dd46880c ] While applying the blamed commit 4ca07b9239bd ("net: mctp i2c: check length before marking flow active"), I unintentionally included unrelated and unacceptable changes. Revert them. Fixes: 4ca07b9239bd ("net: mctp i2c: check length before marking flow active") Reported-by: Jeremy Kerr Closes: https://lore.kernel.org/netdev/bd8704fe0bd53e278add5cde4873256656623e2e.camel@codeconstruct.com.au/ Signed-off-by: Paolo Abeni Link: https://patch.msgid.link/043026a53ff84da88b17648c4b0d17f0331749cb.1777447863.git.pabeni@redhat.com Signed-off-by: Paolo Abeni Signed-off-by: Sasha Levin

net/sched: sch_cake: annotate data-races in cake_dump_stats() (V)

2026-06-01T15:39:29+00:00

[ Upstream commit a6c95b833dc17e84d16a8ac0f40fd0931616a52d ] cake_dump_stats() runs without qdisc spinlock being held. In this final patch, I add READ_ONCE()/WRITE_ONCE() annotations for cparams.target and cparams.interval. Fixes: 046f6fd5daef ("sched: Add Common Applications Kept Enhanced (cake) qdisc") Signed-off-by: Eric Dumazet Acked-by: "Toke Høiland-Jørgensen" Link: https://patch.msgid.link/20260427083606.459355-6-edumazet@google.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin

net: mctp i2c: check length before marking flow active

2026-06-01T15:39:28+00:00

[ Upstream commit 4ca07b9239bd0478ae586632a2ed72be37ed8407 ] Currently, mctp_i2c_get_tx_flow_state() is called before the packet length sanity check. This function marks a new flow as active in the MCTP core. If the sanity check fails, mctp_i2c_xmit() returns early without calling mctp_i2c_lock_nest(). This results in a mismatched locking state: the flow is active, but the I2C bus lock was never acquired for it. When the flow is later released, mctp_i2c_release_flow() will see the active state and queue an unlock marker. The TX thread will then decrement midev->i2c_lock_count from 0, causing it to underflow to -1. This underflow permanently breaks the driver's locking logic, allowing future transmissions to occur without holding the I2C bus lock, leading to bus collisions and potential hardware hangs. Move the mctp_i2c_get_tx_flow_state() call to after the length sanity check to ensure we only transition the flow state if we are actually going to proceed with the transmission and locking. Fixes: f5b8abf9fc3d ("mctp i2c: MCTP I2C binding driver") Signed-off-by: William A. Kennington III Acked-by: Jeremy Kerr Link: https://patch.msgid.link/20260423074741.201460-1-william@wkennington.com Signed-off-by: Paolo Abeni Signed-off-by: Sasha Levin

net/sched: sch_fq_pie: annotate data-races in fq_pie_dump_stats()

2026-06-01T15:39:28+00:00

[ Upstream commit 59b145771c7982cfe9020d4e9e22da92d6b5ae31 ] fq_codel_dump_stats() acquires the qdisc spinlock a bit too late. Move this acquisition before we fill tc_fq_pie_xstats with live data. Alternative would be to add READ_ONCE() and WRITE_ONCE() annotations, but the spinlock is needed anyway to scan q->new_flows and q->old_flows. Fixes: ec97ecf1ebe4 ("net: sched: add Flow Queue PIE packet scheduler") Signed-off-by: Eric Dumazet Reviewed-by: Jamal Hadi Salim Link: https://patch.msgid.link/20260423063527.2568262-1-edumazet@google.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin

net/sched: sch_choke: annotate data-races in choke_dump_stats()

2026-06-01T15:39:28+00:00

[ Upstream commit d3aeb889dcbd78e95f500d383799a23d949796e0 ] choke_dump_stats() only runs with RTNL held. It reads fields that can be changed in qdisc fast path. Add READ_ONCE()/WRITE_ONCE() annotations. Fixes: edb09eb17ed8 ("net: sched: do not acquire qdisc spinlock in qdisc/class stats dump") Signed-off-by: Eric Dumazet Reviewed-by: Jamal Hadi Salim Link: https://patch.msgid.link/20260423062839.2524324-1-edumazet@google.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin

net/sched: netem: fix slot delay calculation overflow

2026-06-01T15:39:28+00:00

[ Upstream commit 51e94e1e2fef351c74d69eb53666df808d26af95 ] get_slot_next() computes a random delay between min_delay and max_delay using: get_random_u32() * (max_delay - min_delay) >> 32 This overflows signed 64-bit arithmetic when the delay range exceeds approximately 2.1 seconds (2^31 nanoseconds), producing a negative result that effectively disables slot-based pacing. This is a realistic configuration for WAN emulation (e.g., slot 1s 5s). Use mul_u64_u32_shr() which handles the widening multiply without overflow. Fixes: 0a9fe5c375b5 ("netem: slotting with non-uniform distribution") Signed-off-by: Stephen Hemminger Reviewed-by: Simon Horman Link: https://patch.msgid.link/20260418032027.900913-6-stephen@networkplumber.org Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin

net/sched: netem: validate slot configuration

2026-06-01T15:39:28+00:00

[ Upstream commit 01801c359a74737b9b1aa28568b60374d857241a ] Reject slot configurations that have no defensible meaning: - negative min_delay or max_delay - min_delay greater than max_delay - negative dist_delay or dist_jitter - negative max_packets or max_bytes Negative or out-of-order delays underflow in get_slot_next(), producing garbage intervals. Negative limits trip the per-slot accounting (packets_left/bytes_left <= 0) on the first packet of every slot, defeating the rate-limiting half of the slot feature. Note that dist_jitter has been silently coerced to its absolute value by get_slot() since the feature was introduced; rejecting negatives here converts that silent coercion into -EINVAL. The abs() can be removed in a follow-up. Fixes: 836af83b54e3 ("netem: support delivering packets in delayed time slots") Signed-off-by: Stephen Hemminger Reviewed-by: Simon Horman Link: https://patch.msgid.link/20260418032027.900913-5-stephen@networkplumber.org Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin

net/sched: netem: fix queue limit check to include reordered packets

2026-06-01T15:39:28+00:00

[ Upstream commit 4185701fcce6b426b6c3630b25330dddd9c47b0d ] The queue limit check in netem_enqueue() uses q->t_len which only counts packets in the internal tfifo. Packets placed in sch->q by the reorder path (__qdisc_enqueue_head) are not counted, allowing the total queue occupancy to exceed sch->limit under reordering. Include sch->q.qlen in the limit check. Fixes: f8d4bc455047 ("net/sched: netem: account for backlog updates from child qdisc") Signed-off-by: Stephen Hemminger Reviewed-by: Simon Horman Link: https://patch.msgid.link/20260418032027.900913-3-stephen@networkplumber.org Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin

net/sched: netem: fix probability gaps in 4-state loss model

2026-06-01T15:39:27+00:00

[ Upstream commit 732b463449fd0ef90acd13cda68eab1c91adb00c ] The 4-state Markov chain in loss_4state() has gaps at the boundaries between transition probability ranges. The comparisons use: if (rnd < a4) else if (a4 < rnd && rnd < a1 + a4) When rnd equals a boundary value exactly, neither branch matches and no state transition occurs. The redundant lower-bound check (a4 < rnd) is already implied by being in the else branch. Remove the unnecessary lower-bound comparisons so the ranges are contiguous and every random value produces a transition, matching the GI (General and Intuitive) loss model specification. This bug goes back to original implementation of this model. Fixes: 661b79725fea ("netem: revised correlated loss generator") Signed-off-by: Stephen Hemminger Reviewed-by: Simon Horman Link: https://patch.msgid.link/20260418032027.900913-2-stephen@networkplumber.org Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin