On Fri, Dec 06, 2019 at 01:55:17PM +0800, Herbert Xu wrote:
> We need to check whether spawn->alg is NULL under lock as otherwise
> the algorithm could be removed from under us after we have checked
> it and found it to be non-NULL. This could cause us to remove the
> spawn from a non-existent list.
>
> Fixes: 6bfd48096ff8 ("[CRYPTO] api: Added spawns")
> Cc: <stable@xxxxxxxxxxxxxxx>
> Signed-off-by: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>
>
> diff --git a/crypto/algapi.c b/crypto/algapi.c
> index 783006f4d339..6869feb31c99 100644
> --- a/crypto/algapi.c
> +++ b/crypto/algapi.c
> @@ -668,11 +668,9 @@ EXPORT_SYMBOL_GPL(crypto_grab_spawn);
>
> void crypto_drop_spawn(struct crypto_spawn *spawn)
> {
> - if (!spawn->alg)
> - return;
> -
> down_write(&crypto_alg_sem);
> - list_del(&spawn->list);
> + if (spawn->alg)
> + list_del(&spawn->list);
> up_write(&crypto_alg_sem);
> }
> EXPORT_SYMBOL_GPL(crypto_drop_spawn);
Seems the Fixes tag is wrong. It should be:
Fixes: 7ede5a5ba55a ("crypto: api - Fix crypto_drop_spawn crash on blank spawns")
- Eric
