{"id":"CVE-2026-46036","summary":"vfio/cdx: Serialize VFIO_DEVICE_SET_IRQS with a per-device mutex","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nvfio/cdx: Serialize VFIO_DEVICE_SET_IRQS with a per-device mutex\n\nvfio_cdx_set_msi_trigger() reads vdev-\u003econfig_msi and operates on the\nvdev-\u003ecdx_irqs array based on its value, but provides no serialization\nagainst concurrent VFIO_DEVICE_SET_IRQS ioctls.  Two callers can race\nsuch that one observes config_msi as set while another clears it and\nfrees cdx_irqs via vfio_cdx_msi_disable(), resulting in a use-after-free\nof the cdx_irqs array.\n\nAdd a cdx_irqs_lock mutex to struct vfio_cdx_device and acquire it in\nvfio_cdx_set_msi_trigger(), which is the single chokepoint through\nwhich all updates to config_msi, cdx_irqs, and msi_count flow, covering\nboth the ioctl path and the close-device cleanup path.  This keeps the\ntest of config_msi atomic with the subsequent enable, disable, or\ntrigger operations.\n\nDrop the pre-call !cdx_irqs test from vfio_cdx_irqs_cleanup() as part\nof this change: the optimization it provided is redundant with the\n!config_msi early-return inside vfio_cdx_msi_disable(), and leaving the\ntest in place would be an unsynchronized read of state the new lock is\nmeant to protect.","modified":"2026-06-18T03:54:56.175640088Z","published":"2026-05-27T12:56:46.381Z","related":["openSUSE-SU-2026:10954-1"],"database_specific":{"cna_assigner":"Linux","osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/46xxx/CVE-2026-46036.json"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/670e8864b1a218d72f08db40d0103adf38fa1d9b"},{"type":"WEB","url":"https://git.kernel.org/stable/c/7530f34ec0ca1438d45a75dcb43183a1cc92eced"},{"type":"WEB","url":"https://git.kernel.org/stable/c/7b436ade16cc81095d79b79f8efa3af0a4f5c5a2"},{"type":"WEB","url":"https://git.kernel.org/stable/c/ddf96e23c366c566283fce8377928851fa7f5e81"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/46xxx/CVE-2026-46036.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-46036"},{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"848e447e000c41894ff931dc7c004fd42c8840f8"},{"fixed":"ddf96e23c366c566283fce8377928851fa7f5e81"},{"fixed":"7b436ade16cc81095d79b79f8efa3af0a4f5c5a2"},{"fixed":"7530f34ec0ca1438d45a75dcb43183a1cc92eced"},{"fixed":"670e8864b1a218d72f08db40d0103adf38fa1d9b"}]}],"database_specific":{"source":"https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2026-46036.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"6.10.0"},{"fixed":"6.12.86"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.13.0"},{"fixed":"6.18.27"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.19.0"},{"fixed":"7.0.4"}]}],"database_specific":{"source":"https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2026-46036.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H"}]}