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

i2c: imx: Fix slave registration race and error handling

In i2c imx reg slave(), the slave pointer was assigned before pm runtime resume and get(). If pm runtime resume and get() failed, the error path returned without clearing i2c imx->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 i2c imx isr() can execute concurrently and, after acquiring slave lock, dereference i2c imx->slave. The previous fix attempt added a lockless i2c imx->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 i2c imx->slave and i2c imx->last slave event to after a successful resume, and by performing the assignment inside the slave lock 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.