From: Lukas Wunner lukas@wunner.de
commit 4def49da620c84a682d9361d6bef0a97eed46fe0 upstream.
Normally the last reference on an spi_controller is released by spi_unregister_controller(). In the case of the i.MX lpspi driver, the spi_controller is registered with devm_spi_register_controller(), so spi_unregister_controller() is invoked automatically after the driver has unbound.
However the driver already releases the last reference in fsl_lpspi_remove() through a gratuitous call to spi_master_put(), causing a use-after-free when spi_unregister_controller() is subsequently invoked by the devres framework.
Fix by dropping the superfluous spi_master_put().
Fixes: 944c01a889d9 ("spi: lpspi: enable runtime pm for lpspi") Signed-off-by: Lukas Wunner lukas@wunner.de Cc: stable@vger.kernel.org # v5.2+ Cc: Han Xu han.xu@nxp.com Link: https://lore.kernel.org/r/ab3c0b18bd820501a12c85e440006e09ec0e275f.160487448... Signed-off-by: Mark Brown broonie@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- drivers/spi/spi-fsl-lpspi.c | 3 --- 1 file changed, 3 deletions(-)
--- a/drivers/spi/spi-fsl-lpspi.c +++ b/drivers/spi/spi-fsl-lpspi.c @@ -973,9 +973,6 @@ static int fsl_lpspi_remove(struct platf spi_controller_get_devdata(controller);
pm_runtime_disable(fsl_lpspi->dev); - - spi_master_put(controller); - return 0; }