{"id":"CVE-2026-46290","summary":"x86/efi: Fix graceful fault handling after FPU softirq changes","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nx86/efi: Fix graceful fault handling after FPU softirq changes\n\nSince commit d02198550423 (\"x86/fpu: Improve crypto performance by\nmaking kernel-mode FPU reliably usable in softirqs\"), kernel_fpu_begin()\ncalls fpregs_lock() which uses local_bh_disable() instead of the\nprevious preempt_disable(). This sets SOFTIRQ_OFFSET in preempt_count\nduring the entire EFI runtime service call, causing in_interrupt() to\nreturn true in normal task context.\n\nThe graceful page fault handler efi_crash_gracefully_on_page_fault()\nuses in_interrupt() to bail out for faults in real interrupt context.\nWith SOFTIRQ_OFFSET now set, the handler always bails out, leaving EFI\nfirmware page faults unhandled. This escalates to die() which also sees\nin_interrupt() as true and calls panic(\"Fatal exception in interrupt\"),\nresulting in a hard system freeze. On systems with buggy firmware that\ntriggers page faults during EFI runtime calls (e.g., accessing unmapped\nmemory in GetTime()), this causes an unrecoverable hang instead of the\nexpected graceful EFI_ABORTED recovery.\n\nFix by replacing in_interrupt() with !in_task(). This preserves the\noriginal intent of bailing for interrupts or NMI faults, while no longer\nfalsely triggering from the FPU code path's local_bh_disable().\n\n[ardb: Sashiko spotted that using 'in_hardirq() || in_nmi()' leaves a\n       window where a softirq may be taken before fpregs_lock() is\n       called, but after efi_rts_work.efi_rts_id has been assigned,\n       and any page faults occurring in that window will then be\n       misidentified as having been caused by the firmware. Instead,\n       use !in_task(), which incorporates in_serving_softirq(). ]","modified":"2026-06-18T03:56:26.009232055Z","published":"2026-06-08T15:46:17.224Z","related":["openSUSE-SU-2026:11014-1"],"database_specific":{"cna_assigner":"Linux","osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/46xxx/CVE-2026-46290.json"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/088f65e206087bf903743bd18417261d7a4c9644"},{"type":"WEB","url":"https://git.kernel.org/stable/c/22b365ba1af3d8c6036b8e5112fffe80998b85a0"},{"type":"WEB","url":"https://git.kernel.org/stable/c/db155b86d1523e85941f61efd7d7ffb594cc9a29"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/46xxx/CVE-2026-46290.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-46290"},{"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":"d02198550423a0b695e7a24ec77153209ad45b09"},{"fixed":"22b365ba1af3d8c6036b8e5112fffe80998b85a0"},{"fixed":"db155b86d1523e85941f61efd7d7ffb594cc9a29"},{"fixed":"088f65e206087bf903743bd18417261d7a4c9644"}]}],"database_specific":{"source":"https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2026-46290.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"6.15.0"},{"fixed":"6.18.30"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.19.0"},{"fixed":"7.0.7"}]}],"database_specific":{"source":"https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2026-46290.json"}}],"schema_version":"1.7.5"}