On Thu, Mar 13, 2025 at 05:16:09PM +0800, Ma Ke wrote:
Once cdev_device_add() failed, we should call put_device() to decrement reference count for cleanup. Or it could cause memory leak.
Found by code review.
Cc: stable@vger.kernel.org Fixes: 493cfaeaa0c9 ("mtd: utilize new cdev_device_add helper function") Signed-off-by: Ma Ke make24@iscas.ac.cn
drivers/mtd/ubi/build.c | 1 + 1 file changed, 1 insertion(+)
diff --git a/drivers/mtd/ubi/build.c b/drivers/mtd/ubi/build.c index ef6a22f372f9..ca4c54cf9fd4 100644 --- a/drivers/mtd/ubi/build.c +++ b/drivers/mtd/ubi/build.c @@ -486,6 +486,7 @@ static int uif_init(struct ubi_device *ubi) kill_volumes(ubi); cdev_device_del(&ubi->cdev, &ubi->dev); out_unreg:
- put_device(&ubi->dev);
Oh wow. No, that's not going to work.
This driver is broken in that there are two different reference counted structures attempting to manage the same chunk of memory. Things will break as your patch here shows.
Please fix this all up to work properly instead, don't think that this change will actually fix anything :(
thanks,
greg k-h