CVEvulnerability
CVE-2026-68286
- Status
- Received
- Published
- 2026-08-10
- Last modified
- 2026-10-03
- Assigner
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Description
In the Linux kernel, the following vulnerability has been resolved:
drop_monitor: perform u64_stats updates under IRQ-disabled section
In net_dm_packet_trace_kfree_skb_hit() and net_dm_hw_trap_packet_probe(),
u64_stats_update_begin() / u64_stats_inc() / u64_stats_update_end() were
called after spin_unlock_irqrestore(&...drop_queue.lock, flags), when local
IRQs had already been re-enabled.
Tracepoint probes can execute in IRQ or softirq context. On 32-bit
architectures, u64_stats_update_begin() disables preemption but not interrupts,
relying on seqcount writes. If a nested interrupt occurs on the same CPU during
the 64-bit stats update, the reentrant seqcount update can corrupt the
seqcount state or stats value.
Fix this by performing the 64-bit per-CPU stats update before releasing
drop_queue.lock via spin_unlock_irqrestore(), ensuring local interrupts remain
disabled during the u64_stats update.
References
- https://git.kernel.org/stable/c/3454c729ee8aa682ec871f1b174b047f731933ae git.kernel.org
- https://git.kernel.org/stable/c/7d857cf5f0120bb0e020fa20b03bd21b9d3e0c04 git.kernel.org
- https://git.kernel.org/stable/c/be9b121894d6ad44f0011f79543a2e3245979497 git.kernel.org
- https://git.kernel.org/stable/c/d5e2cd2bc8ae36617346b3a54ee9da61d866bf92 git.kernel.org
- https://git.kernel.org/stable/c/dd8472526a04f2185afd792b8041a912a7d75d85 git.kernel.org
- https://git.kernel.org/stable/c/fd098a23bf8fda7eae48db9b06e7c34fc4d228fa git.kernel.org