get_user_pages_fast() can return zero in certain error paths. We should handle that or else it means we accidentally return ERR_PTR(0) which is NULL instead of an error pointer. The callers are not expecting that and will crash with a NULL dereference. Fixes: 033ddf12bcf5 ("tee: add register user memory") Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx> diff --git a/drivers/tee/tee_shm.c b/drivers/tee/tee_shm.c index 04e1b8b37046..cdeb4156acda 100644 --- a/drivers/tee/tee_shm.c +++ b/drivers/tee/tee_shm.c @@ -283,7 +283,7 @@ struct tee_shm *tee_shm_register(struct tee_context *ctx, unsigned long addr, if (rc > 0) shm->num_pages = rc; if (rc != num_pages) { - if (rc > 0) + if (rc >= 0) rc = -ENOMEM; ret = ERR_PTR(rc); goto err; -- To unsubscribe from this list: send the line "unsubscribe kernel-janitors" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html