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charset="UTF-8" Content-Transfer-Encoding: quoted-printable 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, Sep 29, 2020 at 8:35 PM Alexander Popov wrot= e: > > Currently in CONFIG_SLAB init_on_free happens too late, and heap > objects go to the heap quarantine being dirty. Lets move memory > clearing before calling kasan_slab_free() to fix that. > > Signed-off-by: Alexander Popov Reviewed-by: Alexander Potapenko > --- > mm/slab.c | 5 +++-- > 1 file changed, 3 insertions(+), 2 deletions(-) > > diff --git a/mm/slab.c b/mm/slab.c > index 3160dff6fd76..5140203c5b76 100644 > --- a/mm/slab.c > +++ b/mm/slab.c > @@ -3414,6 +3414,9 @@ static void cache_flusharray(struct kmem_cache *cac= hep, struct array_cache *ac) > static __always_inline void __cache_free(struct kmem_cache *cachep, void= *objp, > unsigned long caller) > { > + if (unlikely(slab_want_init_on_free(cachep))) > + memset(objp, 0, cachep->object_size); > + > /* Put the object into the quarantine, don't touch it for now. */ > if (kasan_slab_free(cachep, objp, _RET_IP_)) > return; > @@ -3432,8 +3435,6 @@ void ___cache_free(struct kmem_cache *cachep, void = *objp, > struct array_cache *ac =3D cpu_cache_get(cachep); > > check_irq_off(); > - if (unlikely(slab_want_init_on_free(cachep))) > - memset(objp, 0, cachep->object_size); > kmemleak_free_recursive(objp, cachep->flags); > objp =3D cache_free_debugcheck(cachep, objp, caller); > memcg_slab_free_hook(cachep, virt_to_head_page(objp), objp); > -- > 2.26.2 > --=20 Alexander Potapenko Software Engineer Google Germany GmbH Erika-Mann-Stra=C3=9Fe, 33 80636 M=C3=BCnchen Gesch=C3=A4ftsf=C3=BChrer: Paul Manicle, Halimah DeLaine Prado Registergericht und -nummer: Hamburg, HRB 86891 Sitz der Gesellschaft: Hamburg