{"id":"CVE-2026-90144","published":"2026-09-17T17:17:07.233","lastModified":"2026-09-17T17:17:07.233","description":"In the Linux kernel, the following vulnerability has been resolved:\n\ndpll: fix NULL deref in dpll_device_ops() during teardown race\n\nWhen the last owner of a dpll device unregisters while a foreign driver\nstill holds a pin on it via dpll_pin_on_pin_register(), the dpll object\nstays alive with an empty registration list. A pin notification queued\nbefore the unregister (e.g. ice reacting to zl3073x_i2c removal) then\nwalks pin->dpll_refs into dpll_device_ops(), which trips the WARN_ON and\ndereferences the missing registration. dpll_lock cannot help because the\nnotification work was queued before the unregistering driver took the\nlock.\n\nTreat the empty registration list as a legitimate transient state. Make\ndpll_priv() and dpll_device_ops() return NULL in that case and make\nevery pin netlink path that resolves a device from a pin skip such\ndplls. dpll_cmd_pin_get_one() picks a ref with a live registration and\nreturns -ENODEV when there is none, the pin dumpit skips such a pin\ninstead of aborting the dump, dpll_msg_add_pin_dplls() and the\nfrequency, esync, reference sync and phase adjust set paths skip dead\nrefs, and dpll_pin_parent_device_set() validates the parent with\ndpll_device_get_by_id(). dpll_pin_register() is the last caller that\ndereferenced the device ops without a check, so move its frequency\nmonitor validation under dpll_lock and tolerate a missing registration\nthere as well.\n\nThe empty registration list is equivalent to a cleared DPLL_REGISTERED\nmark, both transitions happen under dpll_lock in dpll_device_register()\nand dpll_device_unregister(). A pin notification for a pin whose dplls\nare all gone is now dropped with -ENODEV instead of crashing, all\ncallers in the core ignore that return value.\n\n WARNING: drivers/dpll/dpll_core.c:1092 at dpll_device_ops+0x24/0x40,\n CPU#83: kworker/u576:3/23471\n Modules linked in: ... ice ... zl3073x_i2c(-) ... zl3073x ...\n Workqueue: ice_dpll_wq ice_dpll_pin_notify_work [ice]\n RIP: 0010:dpll_device_ops+0x24/0x40\n Call Trace:\n  <TASK>\n  dpll_cmd_pin_get_one+0x336/0x520\n  dpll_pin_event_send+0x82/0x140\n  dpll_pin_on_pin_unregister+0xbb/0x160\n  ice_dpll_pin_notify_work+0x1bc/0x1f0 [ice]\n  process_one_work+0x19e/0x370\n  worker_thread+0x1a6/0x310\n  kthread+0xe4/0x120\n  ret_from_fork+0x1a1/0x270\n  ret_from_fork_asm+0x1a/0x30\n  </TASK>\n ---[ end trace 0000000000000000 ]---\n BUG: kernel NULL pointer dereference, address: 0000000000000010\n #PF: supervisor read access in kernel mode\n #PF: error_code(0x0000) - not-present page","cvssScore":null,"cvssSeverity":null,"cvssVector":null,"cwes":[],"vendors":[],"products":[],"references":[{"url":"https://git.kernel.org/stable/c/33f016b23a219fe034213849b51436b8e79df251","tags":[]},{"url":"https://git.kernel.org/stable/c/fdbf04e3e01a872d0ef2149f846f1a3e3cb54f5b","tags":[]}],"exploitRefs":[],"hasPoc":false,"ai":null}