net sched

About this tag
The net sched tag covers discussions about the Linux kernel's network scheduler (net/sched), specifically focusing on security vulnerabilities and bugs in queueing disciplines (qdiscs). Recent threads detail CVE-2025-38350, a use-after-free flaw in classful qdisc handling during enqueue operations, and CVE-2025-39677, a backlog accounting bug affecting qdiscs like hhf, fq, fq_codel, and fq_pie. These issues impact multi-tenant and network-facing hosts, with Microsoft's Azure Linux being one affected product. The tag is relevant for system administrators and security professionals managing Linux-based systems, particularly those using hierarchical traffic control or relying on accurate qdisc statistics.

  1. CVE-2025-38350: Linux Kernel Patch Fixes Qdisc Use-After-Free

    The Linux kernel patch for CVE-2025-38350 fixes a subtle but recurring logic gap in the traffic‑control (net/sched) classful qdisc handling that can lead to a use‑after‑free when a child qdisc unexpectedly goes empty during an enqueue operation, and operators should treat multi‑tenant and...
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    • Thread
    • cve 2025 38350 linux kernel net sched network security
    • Replies: 0
    • Forum: Security Alerts

  2. CVE-2025-39677: Linux Net Sched Backlog Bug and Azure Linux Attestation

    The Linux kernel CVE tracked as CVE‑2025‑39677 fixes a subtle but real backlog accounting bug in net/sched that affects several widely used queuing disciplines (hhf, fq, fq_codel, fq_pie). Microsoft’s MSRC statement that “Azure Linux includes this open‑source library and is therefore potentially...
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    • Thread
    • azure linux backlog accounting linux kernel net sched
    • Replies: 0
    • Forum: Security Alerts