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

i2c: imx: Fix slave registration race and error handling

In i2cimxregslave(), the slave pointer was assigned before pmruntimeresumeandget(). If pmruntimeresumeandget() failed, the error path returned without clearing i2cimx->slave, leaving it non-NULL and causing all subsequent registration attempts to fail with -EBUSY.

Additionally, because this driver uses a shared IRQ, the interrupt handler i2cimxisr() can execute concurrently and, after acquiring slavelock, dereference i2cimx->slave. The previous fix attempt added a lockless i2cimx->slave = NULL on the error path, but that could race with the ISR under the lock and still cause a NULL pointer dereference.

Fix both issues by deferring the assignment of i2cimx->slave and i2cimx->lastslaveevent to after a successful resume, and by performing the assignment inside the slavelock critical section. This guarantees that the slave pointer is never left stale on the error path and is always valid when observed by the interrupt handler.