{"api_version":"1","generated_at":"2026-10-22T07:13:32+00:00","cve":"CVE-2026-98395","urls":{"html":"https://cve.report/CVE-2026-98395","api":"https://cve.report/api/cve/CVE-2026-98395.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-98395","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-98395"},"summary":{"title":"powerpc/entry: Fix irq_soft_mask corruption on replayed interrupt exit","description":"In the Linux kernel, the following vulnerability has been resolved:\n\npowerpc/entry: Fix irq_soft_mask corruption on replayed interrupt exit\n\nWhen __replay_soft_interrupts() replays a pending interrupt (e.g.\nPACA_IRQ_DEC -> timer_interrupt), it calls the handler directly with a\nsynthetic pt_regs. The DEFINE_INTERRUPT_HANDLER_ASYNC wrapper around\neach handler calls arch_interrupt_async_exit_prepare() on the way out,\nwhich calls arch_interrupt_exit_prepare() -> local_irq_disable() ->\narch_local_irq_disable(), which does:\n\n    irq_soft_mask_set(IRQS_DISABLED)   /* 0x1 */\n\nThis unconditionally overwrites irq_soft_mask with IRQS_DISABLED (0x1),\nstripping the IRQS_PMI_DISABLED (0x2) bit. The result is that\nirq_soft_mask is 0x1 instead of IRQS_ALL_DISABLED (0x3) when the\nhandler returns to __replay_soft_interrupts().\n\nFor a normally-taken interrupt this is harmless: the next interrupt\nalways enters through arch_interrupt_enter_prepare() which\nunconditionally sets irq_soft_mask to IRQS_ALL_DISABLED. But during\nreplay, next_interrupt() is called directly between replayed handlers\nwithout going back through arch_interrupt_enter_prepare(), so the\nstripped bit is never restored. next_interrupt() then fires a WARNING:\n\n    WARNING: arch/powerpc/kernel/irq_64.c:75\n    WARN_ON(irq_soft_mask_return() != IRQS_ALL_DISABLED)\n\nThe warning was observed early in boot on a POWER10 pseries guest\nduring kmem_cache_init_late(), where a spinlock release triggers\ninterrupt replay that processes a pending timer interrupt.\n\nDebugger state confirming the bug:\n  Before timer_interrupt(&regs):\n    irq_soft_mask = 0x3 (IRQS_ALL_DISABLED)   correct\n    irq_happened  = 0x41 (HARD_DIS|REPLAYING)  correct\n  After timer_interrupt(&regs) returns:\n    irq_soft_mask = 0x1 (IRQS_DISABLED)        WRONG - PMI bit stripped\n    irq_happened  = 0x41                        unchanged\n\nThe fix is to replace local_irq_disable() with hard_irq_disable().\n\nhard_irq_disable() is the right primitive here for two reasons:\n\n1. On PPC64 (hw_irq.h:301) it calls irq_soft_mask_set_return(IRQS_ALL_DISABLED),\n   setting the soft mask to 0x3 (both IRQS_DISABLED and IRQS_PMI_DISABLED),\n   which preserves the PMI bit and fixes the WARNING. The additional\n   work it does (__hard_irq_disable(), PACA_IRQ_HARD_DIS |=) is\n   redundant but safe since both are already set at this point in the\n   exit path; the trace_hardirqs_off() inside is guarded by\n   if (!arch_irqs_disabled_flags(flags)) so it will not double-fire.\n\n2. On PPC32 (hw_irq.h:467) hard_irq_disable() maps to\n   arch_local_irq_disable() -> __hard_irq_disable(), which clears\n   MSR[EE] in hardware. This is exactly correct: PPC32 has no soft-mask\n   PACA mechanism, so the hardware disable is the right way to satisfy\n   irqentry_exit()'s requirement. This also fixes a build error on PPC32\n   where irq_soft_mask_set() is only defined under CONFIG_PPC64:\n\n       arch/powerpc/include/asm/entry-common.h:273: error: implicit\n       declaration of function 'irq_soft_mask_set'\n\n   Using hard_irq_disable() requires no #ifdef and is consistent with\n   how the rest of the entry code (e.g. entry-common.h:463) handles the\n   same PPC32/PPC64 split.","state":"PUBLISHED","assigner":"Linux","published_at":"2026-10-14 14:17:50","updated_at":"2026-10-19 10:18:42"},"problem_types":[],"metrics":[],"references":[{"url":"https://git.kernel.org/stable/c/63a7531ca31f9f097d9cc1cc3fe86ae683cdabdd","name":"https://git.kernel.org/stable/c/63a7531ca31f9f097d9cc1cc3fe86ae683cdabdd","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/95cd316a896f1c1aa4ee4a817ba3d4691103c81b","name":"https://git.kernel.org/stable/c/95cd316a896f1c1aa4ee4a817ba3d4691103c81b","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-98395","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-98395","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 334f3f6d7a1660fd65597bad9960bfa33a716d35 95cd316a896f1c1aa4ee4a817ba3d4691103c81b git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 334f3f6d7a1660fd65597bad9960bfa33a716d35 63a7531ca31f9f097d9cc1cc3fe86ae683cdabdd git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 7.2","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.2 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.2.7 7.2.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.3 * original_commit_for_fix","platforms":[]}],"timeline":[],"solutions":[],"workarounds":[],"exploits":[],"credits":[],"nvd_cpes":[],"vendor_comments":[],"enrichments":{"kev":null,"epss":null,"legacy_qids":[]},"source_records":{"cve_program":{"containers":{"cna":{"affected":[{"defaultStatus":"unaffected","product":"Linux","programFiles":["arch/powerpc/include/asm/entry-common.h"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"lessThan":"95cd316a896f1c1aa4ee4a817ba3d4691103c81b","status":"affected","version":"334f3f6d7a1660fd65597bad9960bfa33a716d35","versionType":"git"},{"lessThan":"63a7531ca31f9f097d9cc1cc3fe86ae683cdabdd","status":"affected","version":"334f3f6d7a1660fd65597bad9960bfa33a716d35","versionType":"git"}]},{"defaultStatus":"affected","product":"Linux","programFiles":["arch/powerpc/include/asm/entry-common.h"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"status":"affected","version":"7.2"},{"lessThan":"7.2","status":"unaffected","version":"0","versionType":"semver"},{"lessThanOrEqual":"7.2.*","status":"unaffected","version":"7.2.7","versionType":"semver"},{"lessThanOrEqual":"*","status":"unaffected","version":"7.3","versionType":"original_commit_for_fix"}]}],"cpeApplicability":[{"nodes":[{"cpeMatch":[{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.2.7","versionStartIncluding":"7.2","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.3","versionStartIncluding":"7.2","vulnerable":true}],"negate":false,"operator":"OR"}]}],"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\npowerpc/entry: Fix irq_soft_mask corruption on replayed interrupt exit\n\nWhen __replay_soft_interrupts() replays a pending interrupt (e.g.\nPACA_IRQ_DEC -> timer_interrupt), it calls the handler directly with a\nsynthetic pt_regs. The DEFINE_INTERRUPT_HANDLER_ASYNC wrapper around\neach handler calls arch_interrupt_async_exit_prepare() on the way out,\nwhich calls arch_interrupt_exit_prepare() -> local_irq_disable() ->\narch_local_irq_disable(), which does:\n\n    irq_soft_mask_set(IRQS_DISABLED)   /* 0x1 */\n\nThis unconditionally overwrites irq_soft_mask with IRQS_DISABLED (0x1),\nstripping the IRQS_PMI_DISABLED (0x2) bit. The result is that\nirq_soft_mask is 0x1 instead of IRQS_ALL_DISABLED (0x3) when the\nhandler returns to __replay_soft_interrupts().\n\nFor a normally-taken interrupt this is harmless: the next interrupt\nalways enters through arch_interrupt_enter_prepare() which\nunconditionally sets irq_soft_mask to IRQS_ALL_DISABLED. But during\nreplay, next_interrupt() is called directly between replayed handlers\nwithout going back through arch_interrupt_enter_prepare(), so the\nstripped bit is never restored. next_interrupt() then fires a WARNING:\n\n    WARNING: arch/powerpc/kernel/irq_64.c:75\n    WARN_ON(irq_soft_mask_return() != IRQS_ALL_DISABLED)\n\nThe warning was observed early in boot on a POWER10 pseries guest\nduring kmem_cache_init_late(), where a spinlock release triggers\ninterrupt replay that processes a pending timer interrupt.\n\nDebugger state confirming the bug:\n  Before timer_interrupt(&regs):\n    irq_soft_mask = 0x3 (IRQS_ALL_DISABLED)   correct\n    irq_happened  = 0x41 (HARD_DIS|REPLAYING)  correct\n  After timer_interrupt(&regs) returns:\n    irq_soft_mask = 0x1 (IRQS_DISABLED)        WRONG - PMI bit stripped\n    irq_happened  = 0x41                        unchanged\n\nThe fix is to replace local_irq_disable() with hard_irq_disable().\n\nhard_irq_disable() is the right primitive here for two reasons:\n\n1. On PPC64 (hw_irq.h:301) it calls irq_soft_mask_set_return(IRQS_ALL_DISABLED),\n   setting the soft mask to 0x3 (both IRQS_DISABLED and IRQS_PMI_DISABLED),\n   which preserves the PMI bit and fixes the WARNING. The additional\n   work it does (__hard_irq_disable(), PACA_IRQ_HARD_DIS |=) is\n   redundant but safe since both are already set at this point in the\n   exit path; the trace_hardirqs_off() inside is guarded by\n   if (!arch_irqs_disabled_flags(flags)) so it will not double-fire.\n\n2. On PPC32 (hw_irq.h:467) hard_irq_disable() maps to\n   arch_local_irq_disable() -> __hard_irq_disable(), which clears\n   MSR[EE] in hardware. This is exactly correct: PPC32 has no soft-mask\n   PACA mechanism, so the hardware disable is the right way to satisfy\n   irqentry_exit()'s requirement. This also fixes a build error on PPC32\n   where irq_soft_mask_set() is only defined under CONFIG_PPC64:\n\n       arch/powerpc/include/asm/entry-common.h:273: error: implicit\n       declaration of function 'irq_soft_mask_set'\n\n   Using hard_irq_disable() requires no #ifdef and is consistent with\n   how the rest of the entry code (e.g. entry-common.h:463) handles the\n   same PPC32/PPC64 split."}],"providerMetadata":{"dateUpdated":"2026-10-19T09:18:48.849Z","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux"},"references":[{"url":"https://git.kernel.org/stable/c/95cd316a896f1c1aa4ee4a817ba3d4691103c81b"},{"url":"https://git.kernel.org/stable/c/63a7531ca31f9f097d9cc1cc3fe86ae683cdabdd"}],"title":"powerpc/entry: Fix irq_soft_mask corruption on replayed interrupt exit","x_generator":{"engine":"bippy-1.2.0"}}},"cveMetadata":{"assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","assignerShortName":"Linux","cveId":"CVE-2026-98395","datePublished":"2026-10-14T13:25:57.887Z","dateReserved":"2026-09-25T10:25:14.346Z","dateUpdated":"2026-10-19T09:18:48.849Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2026-10-14 14:17:50","lastModifiedDate":"2026-10-19 10:18:42","problem_types":[],"metrics":[],"configurations":[]},"legacy_mitre":{"record":{"CveYear":"2026","CveId":"98395","Ordinal":"1","Title":"powerpc/entry: Fix irq_soft_mask corruption on replayed interrup","CVE":"CVE-2026-98395","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"98395","Ordinal":"1","NoteData":"In the Linux kernel, the following vulnerability has been resolved:\n\npowerpc/entry: Fix irq_soft_mask corruption on replayed interrupt exit\n\nWhen __replay_soft_interrupts() replays a pending interrupt (e.g.\nPACA_IRQ_DEC -> timer_interrupt), it calls the handler directly with a\nsynthetic pt_regs. The DEFINE_INTERRUPT_HANDLER_ASYNC wrapper around\neach handler calls arch_interrupt_async_exit_prepare() on the way out,\nwhich calls arch_interrupt_exit_prepare() -> local_irq_disable() ->\narch_local_irq_disable(), which does:\n\n    irq_soft_mask_set(IRQS_DISABLED)   /* 0x1 */\n\nThis unconditionally overwrites irq_soft_mask with IRQS_DISABLED (0x1),\nstripping the IRQS_PMI_DISABLED (0x2) bit. The result is that\nirq_soft_mask is 0x1 instead of IRQS_ALL_DISABLED (0x3) when the\nhandler returns to __replay_soft_interrupts().\n\nFor a normally-taken interrupt this is harmless: the next interrupt\nalways enters through arch_interrupt_enter_prepare() which\nunconditionally sets irq_soft_mask to IRQS_ALL_DISABLED. But during\nreplay, next_interrupt() is called directly between replayed handlers\nwithout going back through arch_interrupt_enter_prepare(), so the\nstripped bit is never restored. next_interrupt() then fires a WARNING:\n\n    WARNING: arch/powerpc/kernel/irq_64.c:75\n    WARN_ON(irq_soft_mask_return() != IRQS_ALL_DISABLED)\n\nThe warning was observed early in boot on a POWER10 pseries guest\nduring kmem_cache_init_late(), where a spinlock release triggers\ninterrupt replay that processes a pending timer interrupt.\n\nDebugger state confirming the bug:\n  Before timer_interrupt(&regs):\n    irq_soft_mask = 0x3 (IRQS_ALL_DISABLED)   correct\n    irq_happened  = 0x41 (HARD_DIS|REPLAYING)  correct\n  After timer_interrupt(&regs) returns:\n    irq_soft_mask = 0x1 (IRQS_DISABLED)        WRONG - PMI bit stripped\n    irq_happened  = 0x41                        unchanged\n\nThe fix is to replace local_irq_disable() with hard_irq_disable().\n\nhard_irq_disable() is the right primitive here for two reasons:\n\n1. On PPC64 (hw_irq.h:301) it calls irq_soft_mask_set_return(IRQS_ALL_DISABLED),\n   setting the soft mask to 0x3 (both IRQS_DISABLED and IRQS_PMI_DISABLED),\n   which preserves the PMI bit and fixes the WARNING. The additional\n   work it does (__hard_irq_disable(), PACA_IRQ_HARD_DIS |=) is\n   redundant but safe since both are already set at this point in the\n   exit path; the trace_hardirqs_off() inside is guarded by\n   if (!arch_irqs_disabled_flags(flags)) so it will not double-fire.\n\n2. On PPC32 (hw_irq.h:467) hard_irq_disable() maps to\n   arch_local_irq_disable() -> __hard_irq_disable(), which clears\n   MSR[EE] in hardware. This is exactly correct: PPC32 has no soft-mask\n   PACA mechanism, so the hardware disable is the right way to satisfy\n   irqentry_exit()'s requirement. This also fixes a build error on PPC32\n   where irq_soft_mask_set() is only defined under CONFIG_PPC64:\n\n       arch/powerpc/include/asm/entry-common.h:273: error: implicit\n       declaration of function 'irq_soft_mask_set'\n\n   Using hard_irq_disable() requires no #ifdef and is consistent with\n   how the rest of the entry code (e.g. entry-common.h:463) handles the\n   same PPC32/PPC64 split.","Type":"Description","Title":"powerpc/entry: Fix irq_soft_mask corruption on replayed interrup"}]}}}