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See http://www.infradead.org/rpr.html X-Rspamd-Server: rspam07 X-Rspamd-Queue-Id: 28332A0011 X-Stat-Signature: rxi1qfztn4pexmfx3wjhbn7dmquwwwoh X-Rspam-User: X-HE-Tag: 1721742305-857823 X-HE-Meta: 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 dlOfGAoy 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 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000001, 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 Tue, Jul 23, 2024 at 01:28:32PM +0200, Uladzislau Rezki wrote: > Concurrent vfree() will lead to use-after-free. Either add a comment > that a user is responsible for not using vrealloc()/vfree() on the same > pointer concurrently or use find_unlink_vmap_area() which might be more > complex when it comes to design of the vrealloc(). You can never use *free concurrently with *realloc. I guess it doesn't hurt to clearly document that, but other than that we should not try to cater to that use pattern at all.