{"id":"CVE-2026-93202","summary":"i3c: master: Fix recursive locking during device registration","details":"In the Linux kernel, the following vulnerability has been resolved:\n\ni3c: master: Fix recursive locking during device registration\n\ni3c_master_register_new_i3c_devs() registers newly discovered devices\nwhile holding i3c_bus_normaluse_lock(), a down_read().  device_register()\ncan immediately probe the device, and probe callbacks typically invoke\nI3C helpers that take i3c_bus_normaluse_lock() again, leading to a\nrecursive acquisition of the same rwsem.  rwsems do not support recursive\nread locking and can deadlock when a writer is waiting.  See the\n\"Recursive read locks\" section of Documentation/locking/lockdep-design.rst.\n\nFor example, with Intel LPSS I3C, LOCKDEP generates a WARNING like:\n  # echo intel-lpss-i3c.0 \u003e /sys/bus/platform/drivers/mipi-i3c-hci/unbind\n  # echo intel-lpss-i3c.0 \u003e /sys/bus/platform/drivers/mipi-i3c-hci/bind\n  WARNING: possible recursive locking detected\n  kworker/5:1/94 is trying to acquire lock:\n  ffff88811c810d78 (&i3cbus-\u003elock){++++}-{4:4}, at: i3c_device_match_id+0x45/0x370\n  but task is already holding lock:\n  ffff88811c810d78 (&i3cbus-\u003elock){++++}-{4:4}, at: i3c_master_reg_work_fn+0x21/0x5f0\n\nFix this by separating device creation from device registration.\nPopulate desc-\u003edev under the maintenance lock, collect the devices that\nstill need registration into a local list, then release the lock before\ncalling device_register().  Finally retake the lock and clean up any\ndevices that failed to register.\n\nUse the maintenance lock rather than the normal-use lock while adding\ndevice objects.  A write-side maintenance lock prevents readers from\nobserving a partially initialized desc-\u003edev during initial device\npopulation, or desc-\u003edev disappearing if registration fails.\n\nThe local list requires a list node, so add a list node member to struct\ni3c_device.","modified":"2026-09-18T03:48:45.020127932Z","published":"2026-09-17T16:12:23.071Z","database_specific":{"cna_assigner":"Linux","osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/93xxx/CVE-2026-93202.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/456f832e5fc26fbfd3b8200fd4553eee520cc377"},{"type":"WEB","url":"https://git.kernel.org/stable/c/9dc73c51ed3ee965c3ddb0ac31cf5c3eea68fa0c"},{"type":"WEB","url":"https://git.kernel.org/stable/c/b25232f66e8cd653d0c6bfdbe534e62a2f9d6a1b"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/93xxx/CVE-2026-93202.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-93202"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"3a379bbcea0af6280e1ca0d1edfcf4e68cde6ee0"},{"fixed":"b25232f66e8cd653d0c6bfdbe534e62a2f9d6a1b"},{"fixed":"9dc73c51ed3ee965c3ddb0ac31cf5c3eea68fa0c"},{"fixed":"456f832e5fc26fbfd3b8200fd4553eee520cc377"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-93202.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"5.0.0"},{"fixed":"6.18.52"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.19.0"},{"fixed":"7.2.6"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-93202.json"}}],"schema_version":"1.9.0"}