mmc: block: Fix use-after-free issue for rpmb

The data structure member “rpmb->md” was passed to a call of the function
“mmc_blk_put” after a call of the function “put_device”. 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@oppo.com>
Cc: stable@vger.kernel.org
[Uffe: Fixed up mangled patch and updated commit message]
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

diff --git a/drivers/mmc/core/block.c b/drivers/mmc/core/block.c
index c5367e2..7896952 100644 (file)
--- a/drivers/mmc/core/block.c
+++ b/drivers/mmc/core/block.c
@@ -2484,8 +2484,8 @@ 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;
 }