modules: only allow symbol_get of EXPORT_SYMBOL_GPL modules

stable inclusion
from stable-v5.10.195
commit f71b0b4a497e3b4c33aa238544fbe1ee9adb01be
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I95JOC

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=f71b0b4a497e3b4c33aa238544fbe1ee9adb01be



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commit 9011e49d upstream.

It has recently come to my attention that nvidia is circumventing the
protection added in 262e6ae7 ("modules: inherit
TAINT_PROPRIETARY_MODULE") by importing exports from their proprietary
modules into an allegedly GPL licensed module and then rexporting them.

Given that symbol_get was only ever intended for tightly cooperating
modules using very internal symbols it is logical to restrict it to
being used on EXPORT_SYMBOL_GPL and prevent nvidia from costly DMCA
Circumvention of Access Controls law suites.

All symbols except for four used through symbol_get were already exported
as EXPORT_SYMBOL_GPL, and the remaining four ones were switched over in
the preparation patches.

Fixes: 262e6ae7 ("modules: inherit TAINT_PROPRIETARY_MODULE")
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: sanglipeng <sanglipeng1@jd.com>