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See http://www.infradead.org/rpr.html X-Rspamd-Server: rspam03 X-Rspam-User: X-Rspamd-Queue-Id: 7323F4001F X-Stat-Signature: qy43nawcqn1yz36ihspj8afz3p9mwd7t X-HE-Tag: 1729666732-153260 X-HE-Meta: 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 umTvNMhb 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 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Wed, Oct 23, 2024 at 08:57:02AM +0200, Marco Elver wrote: > On Wed, 23 Oct 2024 at 08:53, Christoph Hellwig wrote: > > > > On Fri, Oct 18, 2024 at 03:11:09PM +0000, Arnd Bergmann wrote: > > > From: Arnd Bergmann > > > > > > This symbol is now used on the kasan test module, so it needs to be > > > exported. > > > > > > ERROR: modpost: "copy_to_kernel_nofault" [mm/kasan/kasan_test.ko] undefined! > > > > Meh, it would be great not to export internal helpers just because > > someone wants to test them. Please just mark that test built-in only > > instead. > > We have EXPORT_SYMBOL_IF_KUNIT. See include/kunit/visibility.h - > that's more appropriate, and also adjust kasan_test.c to do > MODULE_IMPORT_NS(EXPORTED_FOR_KUNIT_TESTING). Thats a little better, but at least in this case I still think it is a very bad idea. copy_to_kernel_nofault is a perfect vector for exploit code to probe writing to kernel address without causing faults so it really should never ever be exported.