[PATCH 6.1 0507/1146] mmc: meson-gx: fix return value check of mmc_add_host()

Greg Kroah-Hartman
2022-12-28T16:10:46Z

From: Yang Yingliang <yangyingliang@huawei.com>

[ Upstream commit 90935f16f2650ab7416fa2ffbe5c28cb39cf3f1e ]

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().

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

Fixes: 51c5d8447bd7 ("MMC: meson: initial support for GX platforms")
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Reviewed-by: Neil Armstrong <neil.armstrong@linaro.org>
Link: https://lore.kernel.org/r/20221108123417.479045-1-yangyingliang@huawei.com
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/mmc/host/meson-gx-mmc.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/mmc/host/meson-gx-mmc.c b/drivers/mmc/host/meson-gx-mmc.c
index df05e60bed9a..6e5ea0213b47 100644
--- a/drivers/mmc/host/meson-gx-mmc.c
+++ b/drivers/mmc/host/meson-gx-mmc.c
@@ -1335,7 +1335,9 @@ static int meson_mmc_probe(struct platform_device *pdev)
}

mmc->ops = &meson_mmc_ops;
- mmc_add_host(mmc);
+ ret = mmc_add_host(mmc);
+ if (ret)
+ goto err_free_irq;

return 0;

--
2.35.1