{"id":"CVE-2023-52993","summary":"x86/i8259: Mark legacy PIC interrupts with IRQ_LEVEL","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nx86/i8259: Mark legacy PIC interrupts with IRQ_LEVEL\n\nBaoquan reported that after triggering a crash the subsequent crash-kernel\nfails to boot about half of the time. It triggers a NULL pointer\ndereference in the periodic tick code.\n\nThis happens because the legacy timer interrupt (IRQ0) is resent in\nsoftware which happens in soft interrupt (tasklet) context. In this context\nget_irq_regs() returns NULL which leads to the NULL pointer dereference.\n\nThe reason for the resend is a spurious APIC interrupt on the IRQ0 vector\nwhich is captured and leads to a resend when the legacy timer interrupt is\nenabled. This is wrong because the legacy PIC interrupts are level\ntriggered and therefore should never be resent in software, but nothing\never sets the IRQ_LEVEL flag on those interrupts, so the core code does not\nknow about their trigger type.\n\nEnsure that IRQ_LEVEL is set when the legacy PCI interrupts are set up.","modified":"2026-04-02T09:43:31.890021Z","published":"2025-03-27T16:43:28.263Z","related":["SUSE-SU-2025:01983-1","SUSE-SU-2025:1176-1","SUSE-SU-2025:1183-1","SUSE-SU-2025:1195-1","SUSE-SU-2025:1241-1"],"database_specific":{"cna_assigner":"Linux","osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2023/52xxx/CVE-2023-52993.json"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/0b08201158f177aab469e356b4d6af24fdd118df"},{"type":"WEB","url":"https://git.kernel.org/stable/c/137f1b47da5f58805da42c1b7811e28c1e353f39"},{"type":"WEB","url":"https://git.kernel.org/stable/c/496975d1a2937f4baadf3d985991b13fc4fc4f27"},{"type":"WEB","url":"https://git.kernel.org/stable/c/5fa55950729d0762a787451dc52862c3f850f859"},{"type":"WEB","url":"https://git.kernel.org/stable/c/744fe9be9665227335539b7a77ece8d9ff62b6c0"},{"type":"WEB","url":"https://git.kernel.org/stable/c/8770cd9d7c14aa99c255a0d08186f0be953e1638"},{"type":"WEB","url":"https://git.kernel.org/stable/c/e284c273dbb4c1ed68d4204bff94d0b10e4a90f5"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2023/52xxx/CVE-2023-52993.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2023-52993"},{"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":"a4633adcdbc15ac51afcd0e1395de58cee27cf92"},{"fixed":"744fe9be9665227335539b7a77ece8d9ff62b6c0"},{"fixed":"496975d1a2937f4baadf3d985991b13fc4fc4f27"},{"fixed":"8770cd9d7c14aa99c255a0d08186f0be953e1638"},{"fixed":"e284c273dbb4c1ed68d4204bff94d0b10e4a90f5"},{"fixed":"0b08201158f177aab469e356b4d6af24fdd118df"},{"fixed":"137f1b47da5f58805da42c1b7811e28c1e353f39"},{"fixed":"5fa55950729d0762a787451dc52862c3f850f859"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2023-52993.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:N/I:N/A:H"}]}