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: [email protected]
Signed-off-by: Fedor Pchelkin <[email protected]>
---
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)
--
2.42.0
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: [email protected]
> Signed-off-by: Fedor Pchelkin <[email protected]>
> ---
> 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?
Cheers,
Hannes
--
Dr. Hannes Reinecke Kernel Storage Architect
[email protected] +49 911 74053 688
SUSE Software Solutions GmbH, Maxfeldstr. 5, 90409 Nürnberg
HRB 36809 (AG Nürnberg), Geschäftsführer: Ivo Totev, Andrew
Myers, Andrew McDonald, Martje Boudien Moerman
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: [email protected]
> > Signed-off-by: Fedor Pchelkin <[email protected]>
> > ---
> > 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
> [email protected] +49 911 74053 688
> SUSE Software Solutions GmbH, Maxfeldstr. 5, 90409 Nürnberg
> HRB 36809 (AG Nürnberg), Geschäftsführer: Ivo Totev, Andrew
> Myers, Andrew McDonald, Martje Boudien Moerman
>