On Mon, Jul 15, 2024 at 04:26:37PM +0300, botta633 wrote:
> From: Ahmed Ehab <bottaawesome633@xxxxxxxxx>
>
> Preventing lockdep_set_subclass from creating a new instance of the
> string literal. Hence, we will always have the same class->name among
> parent and subclasses. This prevents kernel panics when looking up a
> lock class while comparing class locks and class names.
>
> Reported-by: <syzbot+7f4a6f7f7051474e40ad@xxxxxxxxxxxxxxxxxxxxxxxxx>
> Fixes: de8f5e4f2dc1f ("lockdep: Introduce wait-type checks")
> Cc: <stable@xxxxxxxxxxxxxxx>
> Signed-off-by: Ahmed Ehab <bottaawesome633@xxxxxxxxx>
This looks good to me.
Regards,
Boqun
> ---
> v3->v4:
> - Fixed subject line truncation.
>
> include/linux/lockdep.h | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/include/linux/lockdep.h b/include/linux/lockdep.h
> index 08b0d1d9d78b..df8fa5929de7 100644
> --- a/include/linux/lockdep.h
> +++ b/include/linux/lockdep.h
> @@ -173,7 +173,7 @@ static inline void lockdep_init_map(struct lockdep_map *lock, const char *name,
> (lock)->dep_map.lock_type)
>
> #define lockdep_set_subclass(lock, sub) \
> - lockdep_init_map_type(&(lock)->dep_map, #lock, (lock)->dep_map.key, sub,\
> + lockdep_init_map_type(&(lock)->dep_map, (lock)->dep_map.name, (lock)->dep_map.key, sub,\
> (lock)->dep_map.wait_type_inner, \
> (lock)->dep_map.wait_type_outer, \
> (lock)->dep_map.lock_type)
> --
> 2.45.2
