11bb6ae21c
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.1604874488.git.lukas@wunner.de
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
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https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.