Affected: Linux

In the Linux kernel, the following vulnerability has been resolved:

i3c: master: adi: initialize the lock before enabling interrupts

adi_i3c_master_probe() requests the IRQ and unmasks REG_IRQ_PENDING_CMDR before the controller's IBI state, transfer queue list and transfer queue lock are initialized. A pending CMDR interrupt can therefore run adi_i3c_master_irq() and take master->xferqueue.lock before the dynamic lock has been initialized.

This issue was found by our static analysis tool and then manually reviewed against the current tree.

The grounded PoC kept the probe ordering and the IRQ path adi_i3c_master_probe() -> adi_i3c_master_irq() -> xferqueue.lock, with a pending CMDR interrupt arriving after REG_IRQ_PENDING_CMDR is unmasked. Lockdep reported:

INFO: trying to register non-static key. you didn't initialize this object before use? lock_acquire+0xbb/0x290 _raw_spin_lock_irqsave+0x36/0x60 adi_i3c_master_irq+0x32/0x56 [vuln_msv] adi_i3c_master_probe+0x5a/0xf47 [vuln_msv]

Initialize the transfer queue and IBI state before requesting and unmasking the IRQ.