[PATCH 4.19 55/95] mmc: block: Fix use-after-free issue for rpmb

From: Greg Kroah-Hartman
Date: Mon Jun 01 2020 - 14:51:50 EST


From: Peng Hao <richard.peng@xxxxxxxx>

[ Upstream commit 202500d21654874aa03243e91f96de153ec61860 ]

The data structure member ârpmb->mdâ was passed to a call of the function
âmmc_blk_putâ after a call of the function âput_deviceâ. Reorder these
function calls to keep the data accesses consistent.

Fixes: 1c87f7357849 ("mmc: block: Fix bug when removing RPMB chardev ")
Signed-off-by: Peng Hao <richard.peng@xxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx
[Uffe: Fixed up mangled patch and updated commit message]
Signed-off-by: Ulf Hansson <ulf.hansson@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/mmc/core/block.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/mmc/core/block.c b/drivers/mmc/core/block.c
index 23bcdbba0cab..c723a1e54b18 100644
--- a/drivers/mmc/core/block.c
+++ b/drivers/mmc/core/block.c
@@ -2485,8 +2485,8 @@ static int mmc_rpmb_chrdev_release(struct inode *inode, struct file *filp)
struct mmc_rpmb_data *rpmb = container_of(inode->i_cdev,
struct mmc_rpmb_data, chrdev);

- put_device(&rpmb->dev);
mmc_blk_put(rpmb->md);
+ put_device(&rpmb->dev);

return 0;
}
--
2.25.1