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CVE PROGRAM SOURCE RECORDUnscored

CVE-2026-45890

xen-netback: reject zero-queue configuration from guest

Description

In the Linux kernel, the following vulnerability has been resolved: xen-netback: reject zero-queue configuration from guest A malicious or buggy Xen guest can write "0" to the xenbus key "multi-queue-num-queues". The connect() function in the backend only validates the upper bound (requested_num_queues > xenvif_max_queues) but not zero, allowing requested_num_queues=0 to reach vzalloc(array_size(0, sizeof(struct xenvif_queue))), which triggers WARN_ON_ONCE(!size) in __vmalloc_node_range(). On systems with panic_on_warn=1, this allows a guest-to-host denial of service. The Xen network interface specification requires the queue count to be "greater than zero". Add a zero check to match the validation already present in xen-blkback, which has included this guard since its multi-queue support was added.

Affected products

Version statuses are supplied by the assigning organization. Consult the original record for detailed ranges and platform conditions.

Linux Linux

Default version status: unaffected

  • 8d3d53b3e43363e79ab9a9ecc149b06c1314b25d to < 2993e0f904c45f8af12917344bb1cac7ccd05a60affected
  • 8d3d53b3e43363e79ab9a9ecc149b06c1314b25d to < 787bfa423228c4b02ba3368128f625d579085353affected
  • 8d3d53b3e43363e79ab9a9ecc149b06c1314b25d to < ce66d6786de45b7ed9cbbdc0988054bf09e58f54affected
  • 8d3d53b3e43363e79ab9a9ecc149b06c1314b25d to < 88b0fced1bbbfdb356a007592604008ffc93a6a1affected
  • 8d3d53b3e43363e79ab9a9ecc149b06c1314b25d to < ec4859ac5c933e3315543a61adc1ca4358006a41affected
  • 8d3d53b3e43363e79ab9a9ecc149b06c1314b25d to < 654780dee9eae419e1648ea58462c4efe54518faaffected
  • 8d3d53b3e43363e79ab9a9ecc149b06c1314b25d to < d99f69ddc70fd9f4b8148add62209a1a8eb5c615affected
  • 8d3d53b3e43363e79ab9a9ecc149b06c1314b25d to < 6d1dc8014334c7fb25719999bca84d811e60a559affected

Linux Linux

Default version status: affected

  • 3.16affected
  • 0 to < 3.16unaffected
  • 5.10.252 to ≤ 5.10.*unaffected
  • 5.15.202 to ≤ 5.15.*unaffected
  • 6.1.165 to ≤ 6.1.*unaffected
  • 6.6.128 to ≤ 6.6.*unaffected
  • 6.12.75 to ≤ 6.12.*unaffected
  • 6.18.14 to ≤ 6.18.*unaffected
  • 6.19.4 to ≤ 6.19.*unaffected
  • 7.0 to ≤ *unaffected

References