CVE Published: 22/05/2024 |
CVE Updated: 17/11/2024 |
CVE Year: 2021 Source: Linux |
Vendor: Linux |
Product: Linux Status : PUBLISHED
CVE-2021-47469 Description
In the Linux kernel, the following vulnerability has been resolved:
spi: Fix deadlock when adding SPI controllers on SPI buses
Currently we have a global spi_add_lock which we take when adding new
devices so that we can check that we\'re not trying to reuse a chip
select that\'s already controlled. This means that if the SPI device is
itself a SPI controller and triggers the instantiation of further SPI
devices we trigger a deadlock as we try to register and instantiate
those devices while in the process of doing so for the parent controller
and hence already holding the global spi_add_lock. Since we only care
about concurrency within a single SPI bus move the lock to be per
controller, avoiding the deadlock.
This can be easily triggered in the case of spi-mux.