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792eac1843
The hwmon core registers the hwmon device before adding sensors to the
thermal core. If that fails, the hwmon device is released and an error
is returned to the caller. From the code flow, it appears to be necessary
to free struct hwmon_device *, allocated with kzalloc(), in that
situation. This is incorrect, since the data structure will be freed
automatically in hwmon_dev_release() when device_unregister() is called.
This used to result in a double free, which was found and fixed with
commit 74e3512731 ("hwmon: (core) Fix double-free in
__hwmon_device_register()"). This is, however, not obvious; any reader
may erroneously conclude that the data structure is not freed.
Add comment explaining why kfree() is not necessary in this situation.
Reported-by: Eduardo Valentin <eduval@amazon.com>
Cc: Eduardo Valentin <eduval@amazon.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
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In order to build the documentation, use ``make htmldocs`` or
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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.