{"id":"CVE-2026-98094","summary":"staging: fbtft: make dirty_lock IRQ-safe","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nstaging: fbtft: make dirty_lock IRQ-safe\n\nfbtft_mkdirty() can be reached from the fbcon rendering path while\nprocessing printk() in hardirq context. Meanwhile, dirty_lock is also\ntaken by fbtft_deferred_io() in workqueue context with local interrupts\nenabled.\n\nLockdep reports a possible IRQ lock inversion involving dirty_lock and\nconsole_owner. A hardirq can interrupt a CPU holding dirty_lock and\nenter the console rendering path, which can attempt to acquire\ndirty_lock again.\n\nThe following lockdep report was observed on an RK3566 system with\nCONFIG_PROVE_LOCKING enabled:\n\n  WARNING: possible irq lock inversion dependency detected\n  swapper/2/0 just changed the state of lock:\n  (console_owner){-...}-{0:0}\n  but this lock took another, HARDIRQ-unsafe lock in the past:\n  (&par-\u003edirty_lock){+.+.}-{2:2}\n\n  CPU0                    CPU1\n  ----                    ----\n  lock(&par-\u003edirty_lock);\n                         local_irq_disable();\n                         lock(console_owner);\n                         lock(&par-\u003edirty_lock);\n  \u003cInterrupt\u003e\n    lock(console_owner);\n\n  *** DEADLOCK ***\n\nUse spin_lock_irqsave() for fbtft_mkdirty() and spin_lock_irq() for\nfbtft_deferred_io(). They only access the dirty line range, so the\nIRQ-off regions remain short.","modified":"2026-09-26T03:48:32.533317294Z","published":"2026-09-25T10:24:25.889Z","database_specific":{"cna_assigner":"Linux","osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/98xxx/CVE-2026-98094.json"},"references":[{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"},{"type":"WEB","url":"https://git.kernel.org/stable/c/2a609e29efbba79f9abd68c4ec8a2bd7ecf291e7"},{"type":"WEB","url":"https://git.kernel.org/stable/c/dcb48fde8003492256dee45815144aa5ed26ce7c"},{"type":"WEB","url":"https://git.kernel.org/stable/c/f0c869df2c33793c8828acaab3e4a5e0176f9f00"},{"type":"WEB","url":"https://git.kernel.org/stable/c/f576944a59f31bcffff121117ebf452c5dd162b7"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/98xxx/CVE-2026-98094.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-98094"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"c296d5f9957c03994a699d6739c27d4581a9f6c7"},{"fixed":"2a609e29efbba79f9abd68c4ec8a2bd7ecf291e7"},{"fixed":"f0c869df2c33793c8828acaab3e4a5e0176f9f00"},{"fixed":"dcb48fde8003492256dee45815144aa5ed26ce7c"},{"fixed":"f576944a59f31bcffff121117ebf452c5dd162b7"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-98094.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"4.0.0"},{"fixed":"6.12.111"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.13.0"},{"fixed":"6.18.53"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.19.0"},{"fixed":"7.2.7"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-98094.json"}}],"schema_version":"1.9.0"}