On 23/09/20 04:06PM, Hannes Reinecke wrote:
> On 9/20/23 12:51, Fedor Pchelkin wrote:
> > Commit 4dba12881f88 ("dm zoned: support arbitrary number of devices")
> > made the pointers to additional zoned devices to be stored in a
> > dynamically allocated dmz->ddev array. However, this array is not freed.
> >
> > Free it when cleaning up zoned device information inside
> > dmz_put_zoned_device(). Assigning NULL to dmz->ddev elements doesn't make
> > sense there as they are not supposed to be reused later and the whole dmz
> > target structure is being cleaned anyway.
> >
> > Found by Linux Verification Center (linuxtesting.org).
> >
> > Fixes: 4dba12881f88 ("dm zoned: support arbitrary number of devices")
> > Cc: stable@xxxxxxxxxxxxxxx
> > Signed-off-by: Fedor Pchelkin <pchelkin@xxxxxxxxx>
> > ---
> > drivers/md/dm-zoned-target.c | 8 +++-----
> > 1 file changed, 3 insertions(+), 5 deletions(-)
> >
> > diff --git a/drivers/md/dm-zoned-target.c b/drivers/md/dm-zoned-target.c
> > index ad8e670a2f9b..e25cd9db6275 100644
> > --- a/drivers/md/dm-zoned-target.c
> > +++ b/drivers/md/dm-zoned-target.c
> > @@ -753,12 +753,10 @@ static void dmz_put_zoned_device(struct dm_target *ti)
> > struct dmz_target *dmz = ti->private;
> > int i;
> > - for (i = 0; i < dmz->nr_ddevs; i++) {
> > - if (dmz->ddev[i]) {
> > + for (i = 0; i < dmz->nr_ddevs; i++)
> > + if (dmz->ddev[i])
> > dm_put_device(ti, dmz->ddev[i]);
> > - dmz->ddev[i] = NULL;
> > - }
> > - }
> > + kfree(dmz->ddev);
> > }
> > static int dmz_fixup_devices(struct dm_target *ti)
>
> Hmm. I'm not that happy with it; dmz_put_zoned_device() is using dm_target
> as an argument, whereas all of the functions surrounding the call sites is
> using the dmz_target directly.
>
> Mind to modify the function to use 'struct dmz_target' as an argument?
dm_target is required inside dmz_put_zoned_device() for dm_put_device()
calls. I can't see a way for referencing it via dmz_target. Do you mean
passing additional second argument like
dmz_put_zoned_device(struct dmz_target *dmz, struct dm_target *ti) ?
BTW, I also think it can be renamed to dmz_put_zoned_devices().
>
> Cheers,
>
> Hannes
> --
> Dr. Hannes Reinecke Kernel Storage Architect
> hare@xxxxxxx +49 911 74053 688
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