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charset="UTF-8" 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: On Tue, 17 Nov 2020 at 14:12, Dmitry Vyukov wrote: > > + */ > > *(u8 *)kasan_mem_to_shadow(object) = KASAN_KMALLOC_FREE; > > + > > ___cache_free(cache, object, _THIS_IP_); > > > > if (IS_ENABLED(CONFIG_SLAB)) > > @@ -168,6 +173,9 @@ void quarantine_put(struct kmem_cache *cache, void *object) > > struct qlist_head temp = QLIST_INIT; > > struct kasan_free_meta *meta = kasan_get_free_meta(cache, object); > > > > + if (!meta) > > + return; > > Humm... is this possible? If yes, we would be leaking the object here... > Perhaps BUG_ON with a comment instead. If this is possible in prod-mode KASAN, a WARN_ON() that returns would be safer.