mmc: mmci: fix return value check of mmc_add_host()

[ Upstream commit b38a20f29a49ae04d23750d104b25400b792b98c ]

mmc_add_host() may return error, if we ignore its return value,
it will lead two issues:
1. The memory that allocated in mmc_alloc_host() is leaked.
2. In the remove() path, mmc_remove_host() will be called to
   delete device, but it's not added yet, it will lead a kernel
   crash because of null-ptr-deref in device_del().

So fix this by checking the return value and goto error path which
will call mmc_free_host().

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Link: https://lore.kernel.org/r/20221109133539.3275664-1-yangyingliang@huawei.com
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/drivers/mmc/host/mmci.c b/drivers/mmc/host/mmci.c
index 3765e2f..2c4eda8 100644 (file)
--- a/drivers/mmc/host/mmci.c
+++ b/drivers/mmc/host/mmci.c
@@ -2254,7 +2254,9 @@ static int mmci_probe(struct amba_device *dev,
        pm_runtime_set_autosuspend_delay(&dev->dev, 50);
        pm_runtime_use_autosuspend(&dev->dev);
 
-       mmc_add_host(mmc);
+       ret = mmc_add_host(mmc);
+       if (ret)
+               goto clk_disable;
 
        pm_runtime_put(&dev->dev);
        return 0;