CVEvulnerability
CVE-2026-68378
- Status
- Received
- Published
- 2026-08-10
- Last modified
- 2026-08-17
- Assigner
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Description
In the Linux kernel, the following vulnerability has been resolved:
dpll: fix NULL pointer dereference in dpll_msg_add_pin_ref_sync()
When a dpll_pin is shared across multiple dpll_device instances and
those devices are being unregistered (e.g. during driver module removal),
a NULL pointer dereference can occur in dpll_msg_add_pin_ref_sync().
This happens under the following conditions:
- A pin is registered with two or more dpll devices (dpll_A, dpll_B)
- The pin has ref_sync pairs with other pins
- During unregistration of dpll_A's pins, a ref_sync partner pin is
unregistered first, removing it from dpll_A->pin_refs
- But since the partner pin is still registered with dpll_B, its
dpll_refs is not empty, so dpll_pin_ref_sync_pair_del() does NOT
run and the partner stays in the pin's ref_sync_pins xarray
- When the pin itself is then unregistered from dpll_A, the delete
notification calls dpll_msg_add_pin_ref_sync() which finds the
partner in ref_sync_pins, passes dpll_pin_available() (partner is
still registered with dpll_B), but dpll_pin_on_dpll_priv(dpll_A,
partner) returns NULL because partner was already removed from
dpll_A->pin_refs
- The NULL priv pointer is passed to the driver's ref_sync_get
callback, which dereferences it
BUG: kernel NULL pointer dereference, address: 0000000000000034
Oops: Oops: 0000 [#1] SMP NOPTI
RIP: 0010:zl3073x_dpll_input_pin_ref_sync_get+0x73/0x80 [zl3073x]
Call Trace:
dpll_msg_add_pin_ref_sync+0xb8/0x200
dpll_cmd_pin_get_one+0x3b6/0x4b0
dpll_pin_event_send+0x72/0x140
__dpll_pin_unregister+0x5a/0x2b0
dpll_pin_unregister+0x49/0x70
Fix this by skipping ref_sync pins whose priv pointer cannot be resolved
for the current dpll device.
References
- https://git.kernel.org/stable/c/4b3e6b9fdaeb40c6a2f7c41db3888b6ee628bdd2 git.kernel.org
- https://git.kernel.org/stable/c/51c2fcc4cd2e4c52bd1970558f6e5356fdc51154 git.kernel.org
- https://git.kernel.org/stable/c/66fbe0499ef517ab161b96c49886a891851f6481 git.kernel.org
- https://git.kernel.org/stable/c/d2e914a4a0d0f753dbae830264850d044026167c git.kernel.org