Skip to main content
cve.nowby Sazabi
← All vulnerabilities
CVE-2026-89549

sunrpc: route to a populated pool in svc_pool_for_cpu()

Published
Last modified
published
Not listed in CISA KEV
Fix
Fixed in 5.10.270, 5.15.221, 6.1.188, 6.6.157, 6.12.109, and 2 more
None on Exploit-DB, Metasploit or GitHub
  • Exploitation: none
  • Automatable: yes
  • Technical impact: partial

Summary

In the Linux kernel, the following vulnerability has been resolved: sunrpc: route to a populated pool in svc_pool_for_cpu() svc_set_num_threads() spreads the requested threads evenly across the service's pools (base = nrservs / sv_nrpools). When a service runs fewer threads than it has pools -- e.g. an nfsd configured with fewer threads than the host has NUMA nodes while running in "pernode" or "percpu" mode -- the trailing pools are left with no threads at all. svc_xprt_enqueue() selects a pool from the CPU servicing the transport, queues the transport on that pool's sp_xprts, and only wakes a thread from the same pool. Each thread services exclusively its own pool, so a transport that lands on a threadless pool is enqueued on sp_xprts and never picked up: the connection hangs indefinitely. Have svc_pool_for_cpu() skip pools that currently have no threads, falling back to the next populated pool. This trades NUMA locality for a guarantee that the work is actually serviced. sp_nrthreads is only updated under the service mutex; the lockless read here is a best-effort routing hint, so annotate it with data_race().

Timeline

  1. CVE published
  2. CISA SSVC assessment

    Exploitation: none · Automatable: yes · Technical impact: partial

  3. Record last updated

Affected versions

  • Linux Linux

    From bfd241600a3b0db4fe43c859f1460d0a958d924a · fixed in 9accc25e5af0bac8479f6054e674b2c593c45281; From bfd241600a3b0db4fe43c859f1460d0a958d924a · fixed in 6f66d38e2a6c78d48723ea17ad86135ec80ca24b; From bfd241600a3b0db4fe43c859f1460d0a958d924a · fixed in d79d7b9e8acbb53e2d60f6b24afc13e2f15e691f; From bfd241600a3b0db4fe43c859f1460d0a958d924a · fixed in edb20e8c03aebacb409968c99d046f509c6c485a; From bfd241600a3b0db4fe43c859f1460d0a958d924a · fixed in 011479cf9a7657d4a3e7cc42a784ac63df594170; From bfd241600a3b0db4fe43c859f1460d0a958d924a · fixed in 9d04d64ad192439835ed9884d767353061c3ed6f; From bfd241600a3b0db4fe43c859f1460d0a958d924a · fixed in 8f766d2d0b4dabf54f8b35812df2b4f481d13316; From bfd241600a3b0db4fe43c859f1460d0a958d924a · fixed in f6310491c4cdb88af73aa551ec9df1f10a90c709

  • Linux Linux

    2.6.19

  • KernelLinux

    From 2.6.19 · fixed in 5.10.270; From 5.11.0 · fixed in 5.15.221; From 5.16.0 · fixed in 6.1.188; From 6.2.0 · fixed in 6.6.157; From 6.7.0 · fixed in 6.12.109; From 6.13.0 · fixed in 6.18.50; From 6.19.0 · fixed in 7.2.4

References 8

git.kernel.org