{ "schemaVersion": 1, "attribution": [ { "source": "CISA Known Exploited Vulnerabilities", "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog", "licence": "US government work" }, { "source": "GitHub Advisory Database", "url": "https://github.com/advisories", "licence": "CC BY 4.0" }, { "source": "Have I Been Pwned", "url": "https://haveibeenpwned.com/", "licence": "CC BY 4.0" }, { "source": "CVE Program (CVE records)", "url": "https://www.cve.org/Legal/TermsOfUse", "licence": "CVE Terms of Use", "notice": "Copyright © 1999-2026, The MITRE Corporation. CVE is a trademark and the CVE logo is a registered trademark of The MITRE Corporation.", "terms": "CVE Usage: MITRE hereby grants you a perpetual, worldwide, non-exclusive, no-charge, royalty-free, irrevocable copyright license to reproduce, prepare derivative works of, publicly display, publicly perform, sublicense, and distribute Common Vulnerabilities and Exposures (CVE™). Any copy you make for such purposes is authorized provided that you reproduce MITRE's copyright designation and this license in any such copy." }, { "source": "FIRST EPSS", "url": "https://www.first.org/epss/", "licence": "free to use; FIRST requests attribution" } ], "record": { "id": "CVE-2026-31667", "sourceURL": "https://www.cve.org/CVERecord?id=CVE-2026-31667", "idYear": 2026, "status": "PUBLISHED", "publishedAt": "2026-04-24T14:45:15.937Z", "updatedAt": "2026-10-19T18:56:02.976Z", "importedAt": "2026-10-24T01:58:02.025Z", "snapshot": { "id": "cve_2026-10-24_midnight_baseline", "at": "2026-10-24T00:00:00.000Z", "source": "https://github.com/CVEProject/cvelistV5/releases/tag/cve_2026-10-24_0100Z" }, "facts": { "title": "Input: uinput - fix circular locking dependency with ff-core", "summary": "In the Linux kernel, the following vulnerability has been resolved:\n\nInput: uinput - fix circular locking dependency with ff-core\n\nA lockdep circular locking dependency warning can be triggered\nreproducibly when using a force-feedback gamepad with uinput (for\nexample, playing ELDEN RING under Wine with a Flydigi Vader 5\ncontroller):\n\n ff->mutex -> udev->mutex -> input_mutex -> dev->mutex -> ff->mutex\n\nThe cycle is caused by four lock acquisition paths:\n\n1. ff upload: input_ff_upload() holds ff->mutex and calls\n uinput_dev_upload_effect() -> uinput_request_submit() ->\n uinput_request_send(), which acquires udev->mutex.\n\n2. device create: uinput_ioctl_handler() holds udev->mutex and calls\n uinput_create_device() -> input_register_device(), which acquires\n input_mutex.\n\n3. device register: input_register_device() holds input_mutex and\n calls kbd_connect() -> input_register_handle(), which acquires\n dev->mutex.\n\n4. evdev release: evdev_release() calls input_flush_device() under\n dev->mutex, which calls input_ff_flush() acquiring ff->mutex.\n\nFix this by introducing a new state_lock spinlock to protect\nudev->state and udev->dev access in uinput_request_send() instead of\nacquiring udev->mutex. The function only needs to atomically check\ndevice state and queue an input event into the ring buffer via\nuinput_dev_event() -- both operations are safe under a spinlock\n(ktime_get_ts64() and wake_up_interruptible() do not sleep). This\nbreaks the ff->mutex -> udev->mutex link since a spinlock is a leaf in\nthe lock ordering and cannot form cycles with mutexes.\n\nTo keep state transitions visible to uinput_request_send(), protect\nwrites to udev->state in uinput_create_device() and\nuinput_destroy_device() with the same state_lock spinlock.\n\nAdditionally, move init_completion(&request->done) from\nuinput_request_send() to uinput_request_submit() before\nuinput_request_reserve_slot(). Once the slot is allocated,\nuinput_flush_requests() may call complete() on it at any time from\nthe destroy path, so the completion must be initialised before the\nrequest becomes visible.\n\nLock ordering after the fix:\n\n ff->mutex -> state_lock (spinlock, leaf)\n udev->mutex -> state_lock (spinlock, leaf)\n udev->mutex -> input_mutex -> dev->mutex -> ff->mutex (no back-edge)", "affected": [ { "vendor": "Linux", "product": "Linux", "defaultStatus": "unaffected", "versions": [ { "version": "ff462551235d8d7d843a005950bc90924fcedede", "status": "affected", "versionType": "git", "lessThan": "71a9729f412e2c692a35c542e14b706fb342927f" }, { "version": "ff462551235d8d7d843a005950bc90924fcedede", "status": "affected", "versionType": "git", "lessThan": "271ee71a1917b89f6d73ec82dd091c33d92ee617" }, { "version": "ff462551235d8d7d843a005950bc90924fcedede", "status": "affected", "versionType": "git", "lessThan": "974f7b138c3a96dd5cd53d1b33409cd7b2229dc6" }, { "version": "ff462551235d8d7d843a005950bc90924fcedede", "status": "affected", "versionType": "git", "lessThan": "546c18a14924eb521fe168d916d7ce28f1e13c1d" }, { "version": "ff462551235d8d7d843a005950bc90924fcedede", "status": "affected", "versionType": "git", "lessThan": "a3d6c9c053c9c605651508569230ead633b13f76" }, { "version": "ff462551235d8d7d843a005950bc90924fcedede", "status": "affected", "versionType": "git", "lessThan": "1e09dfbb4f5d20ee111f92325a00f85778a5f328" }, { "version": "ff462551235d8d7d843a005950bc90924fcedede", "status": "affected", "versionType": "git", "lessThan": "1534661043c434b81cfde26b97a2fb2460329cf0" }, { "version": "ff462551235d8d7d843a005950bc90924fcedede", "status": "affected", "versionType": "git", "lessThan": "4cda78d6f8bf2b700529f2fbccb994c3e826d7c2" } ] }, { "vendor": "Linux", "product": "Linux", "defaultStatus": "affected", "versions": [ { "version": "2.6.19", "status": "affected" }, { "version": "0", "status": "unaffected", "versionType": "semver", "lessThan": "2.6.19" }, { "version": "5.10.253", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "5.10.*" }, { "version": "5.15.203", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "5.15.*" }, { "version": "6.1.169", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "6.1.*" }, { "version": "6.6.135", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "6.6.*" }, { "version": "6.12.82", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "6.12.*" }, { "version": "6.18.23", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "6.18.*" }, { "version": "6.19.13", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "6.19.*" }, { "version": "7.0", "status": "unaffected", "versionType": "original_commit_for_fix", "lessThanOrEqual": "*" } ] } ] } } }