mmc: card: Avoid null pointer dereference

After the null check on md the code jumped to cmd_done, which then
will dereference md in mmc_blk_put. This patch avoids the possible
null pointer dereference in that case.

Signed-off-by: Philippe De Swert <philippedeswert@gmail.com>
Reviewed-by: Namjae Jeon <linkinjeon@gmail.com>
Signed-off-by: Chris Ball <cjb@laptop.org>

diff --git a/drivers/mmc/card/block.c b/drivers/mmc/card/block.c
index dabec556ebb87421f04372ecf1452b645629ab17..91cda7551a607ed8592327ec99e51642cd18eddc 100644 (file)
--- a/drivers/mmc/card/block.c
+++ b/drivers/mmc/card/block.c
@@ -384,7 +384,7 @@ static int mmc_blk_ioctl_cmd(struct block_device *bdev,
        md = mmc_blk_get(bdev->bd_disk);
        if (!md) {
                err = -EINVAL;
-               goto cmd_done;
+               goto cmd_err;
        }
 
        card = md->queue.card;
@@ -483,6 +483,7 @@ cmd_rel_host:
 
 cmd_done:
        mmc_blk_put(md);
+cmd_err:
        kfree(idata->buf);
        kfree(idata);
        return err;