[PATCH 6.1 0509/1146] mmc: wbsd: fix return value check of mmc_add_host()

Greg Kroah-Hartman
2022-12-28T16:06:09Z

From: Yang Yingliang <yangyingliang@huawei.com>

[ Upstream commit dc5b9b50fc9d1334407e316e6e29a5097ef833bd ]

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(), besides, other resources also need be
released.

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Link: https://lore.kernel.org/r/20221109133237.3273558-1-yangyingliang@huawei.com
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/mmc/host/wbsd.c | 12 +++++++++++-
1 file changed, 11 insertions(+), 1 deletion(-)

diff --git a/drivers/mmc/host/wbsd.c b/drivers/mmc/host/wbsd.c
index 67ecd342fe5f..7c7ec8d10232 100644
--- a/drivers/mmc/host/wbsd.c
+++ b/drivers/mmc/host/wbsd.c
@@ -1698,7 +1698,17 @@ static int wbsd_init(struct device *dev, int base, int irq, int dma,
*/
wbsd_init_device(host);

- mmc_add_host(mmc);
+ ret = mmc_add_host(mmc);
+ if (ret) {
+ if (!pnp)
+ wbsd_chip_poweroff(host);
+
+ wbsd_release_resources(host);
+ wbsd_free_mmc(dev);
+
+ mmc_free_host(mmc);
+ return ret;
+ }

pr_info("%s: W83L51xD", mmc_hostname(mmc));
if (host->chip_id != 0)
--
2.35.1