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Howlett" , Nico Pache , Ryan Roberts , Dev Jain , Lance Yang , linux-mm@kvack.org, linux-kernel@vger.kernel.org, stable@vger.kernel.org Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Rspamd-Queue-Id: 452E6180003 X-Stat-Signature: 8kq8uwqdmgepf38cuoueqjitcimeepq3 X-Rspam-User: X-Rspamd-Server: rspam02 X-HE-Tag: 1775896487-536428 X-HE-Meta: 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 KtiRx+DZ 0GsurEP8tqTtgLagse/N4aKD97tHR1aIGcax5LD4LNI3uZFv7RE2gT2TLwMlXcfWWjooBkRwBPthZDWnrU+2UqA5MiOKX3xDSfambwlzmFdCllJssM1KWCJMLe77ZvHTCeIYd/70LV/U3vgZIQ5xhz33aYfdeZRnRJqHKqIcgNQkbUHuho1avvmJPYijCMdv26vg2veznF4QzNpDjsHKXEzxeSovHztmO4FuBFK1kMkIUXmbfZviGjcJayusoSzWApfwleu6RTSlHwsWhXGbDGU8o/Ow7Ahag+9zITDAdundqan4keicHW7MtZdBrMB6gmPRKVfskisjxDjGnKK3dQLB75nzXj/FVnCxN/l596U+hM1IxSQqhx+L3Z7ltCggiumz4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Sat, Apr 11, 2026 at 4:32=E2=80=AFPM Barry Song wrot= e: > > On Sat, Apr 11, 2026 at 2:22=E2=80=AFPM Guangshuo Li wrote: > > > > After kobject_init_and_add(), the lifetime of the embedded struct > > kobject is expected to be managed through the kobject core reference > > counting. > > > > In thpsize_create(), if kobject_init_and_add() fails, thpsize is freed > > directly with kfree() rather than releasing the kobject reference with > > kobject_put(). This may leave the reference count of the embedded struc= t > > kobject unbalanced, resulting in a refcount leak and potentially leadin= g > > to a use-after-free. > > > > Fix this by using kobject_put(&thpsize->kobj) in the failure path and > > letting thpsize_release() handle the final cleanup. > > > > Fixes: 3485b88390b0 ("mm: thp: introduce multi-size THP sysfs interface= ") > > Cc: stable@vger.kernel.org > > Signed-off-by: Guangshuo Li > > I=E2=80=99m fine with the patch, but could you send a v2 to drop > the err label, which is no longer used? Alternatively, > could you rename err_put to err? > > @@ -825,9 +825,8 @@ static struct thpsize *thpsize_create(int order, > struct kobject *parent) > } > > return thpsize; > -err_put: > - kobject_put(&thpsize->kobj); > err: > + kobject_put(&thpsize->kobj); > return ERR_PTR(ret); > } Sorry, my mistake=E2=80=94err is still used by kzalloc_obj. Reviewed-by: Barry Song